I had a surprise email from our friend Kevin at Zero Exhausts; he now has perfect bespoke 200cell cat pipes for the mr2.
It's a thing of beauty, as is to be expected.
Top quality steel as we know from his manifolds and a Magnaflow 200cell.
He has quoted the price at 320,which quite frankly pisses me off as I paid a lot more for mine... :(
He wrote:
"I have used a top quality catalytic converter from Magnaflow in the USA and it is rated as safe to 300bhp. As you can see the flanges are machined to accept the O.E. gaskets. The quality speaks for itself I think and it shouldn't be compared to the £195 versions that can be found on Ebay which use plain gaskets to mate to the pre-cats and the exhaust silencer, have a lot smaller catalytic converter and a lot shorter braided flex."
Very nice. Proper bit of kit.
Quote from: Carolyn on February 18, 2020, 20:12Very nice. Proper bit of kit.
That it is.
If anybody does get it, it would be nice to have the forum mentioned. I don't know if the 320gbp price is forum-only but it's good for him to get an idea of where his mr2 clientele are coming from.
Yes that does look a good bit of kit, got to fit better than the one I've got.
Well that sucks! Or blows, technically... Being in the same boat as Patrick I can't help feeling a little disappointed but that's life, I'd only destroy it anyway, probably.
Lovely looking thing though, not dissimilar to my own in parts.
Hmmmm...
how does the connection between the manifold and the cat actually look like then? The zero manifold has slight recesses that help to keep circle gaskets in place, but that cat has tube extensions sticking out.. are they supposed to fit into the manifold tubes?
Standard gaskets are what like 4mm thick?
I like the idea of getting one, along with Snelbards braces etc but just curious how the connection works..
Quote from: jvanzyl on February 18, 2020, 22:30Hmmmm...
how does the connection between the manifold and the cat actually look like then? The zero manifold has slight recesses that help to keep circle gaskets in place, but that cat has tube extensions sticking out.. are they supposed to fit into the manifold tubes?
Standard gaskets are what like 4mm thick?
I like the idea of getting one, along with Snelbards braces etc but just curious how the connection works..
It's the same as stock. He copied the flanges on both sides.
I've got a different view. The 200 cell Magnaflow can be bought for approx £100. A stainless de-cat pipe can be had for under £100. If you know a welder.....
I'll add I bought a Zero manifold.
Quote from: Gaz mr-s on February 18, 2020, 23:32I've got a different view. The 200 cell Magnaflow can be bought for approx £100. A stainless de-cat pipe can be had for under £100. If you know a welder.....
I'll add I bought a Zero manifold.
Same as the Zero mani; you can do things on the cheap, have questionable stainless and generic flanges needing non-standard gaskets, or you can pay a little more and get a top quality, perfectly fitting piece of kit with warranty.
They both "do the job". Preference really.
Quote from: Gaz mr-s on February 18, 2020, 23:32I've got a different view. The 200 cell Magnaflow can be bought for approx £100. A stainless de-cat pipe can be had for under £100. If you know a welder.....
I'll add I bought a Zero manifold.
100 + 100 + 50 + agro < 320 you say, meaning the agro is worth less than 70 quid.
Ok, that is a pov.
I´d prefer not leaking joints and guaranteed weld quality.
If you use a garage that gives you agro then maybe you should look elsewhere, Petrus.
There are two practical advantages to getting a Zero-made one....the steel quality & the o/e spec flange.
But a cat pipe is not going to stay pretty for very long, & it's more effective if wrapped. So if the welding isn't as good as Zero's it won't matter if it's wrapped.
That looks good, finish and weld quality look spot on, £320 is not expensive imo
Rob
Quote from: Zxrob on February 19, 2020, 16:07That looks good, finish and weld quality look spot on, £320 is not expensive imo
Rob
I agree!
I went to look at his website, but it is not on there yet. Sending him an email.
Quote from: Gaz mr-s on February 19, 2020, 15:38If you use a garage that gives you agro then maybe you should look elsewhere, Petrus.
There are two practical advantages to getting a Zero-made one....the steel quality & the o/e spec flange.
But a cat pipe is not going to stay pretty for very long, & it's more effective if wrapped. So if the welding isn't as good as Zero's it won't matter if it's wrapped.
I think you have misunderstoor my equasion.
And about the wrapping; it has two sides in this case. Yes it will make the cat work quicker/well but it will put extra thermal stress on the welds so if the welding is not as good... hmmm.
For perspective: I have a decat header, a decat mid pipe and OEM connections welded to a motorbike demuffler. Nothing wrapped.
Quote from: Petrus on February 19, 2020, 18:49Quote from: Gaz mr-s on February 19, 2020, 15:38If you use a garage that gives you agro then maybe you should look elsewhere, Petrus.
There are two practical advantages to getting a Zero-made one....the steel quality & the o/e spec flange.
But a cat pipe is not going to stay pretty for very long, & it's more effective if wrapped. So if the welding isn't as good as Zero's it won't matter if it's wrapped.
I think you have misunderstoor my equasion.
And about the wrapping; it has two sides in this case. Yes it will make the cat work quicker/well but it will put extra thermal stress on the welds so if the welding is not as good... hmmm.
For perspective: I have a decat header, a decat mid pipe and OEM connections welded to a motorbike demuffler. Nothing wrapped.
This guy's welding is top quality. He is very happy with wrapping his product.
I have ordered one now. Looking forward to receive it. >:D >:D
Quote from: Bugster_MR2 on February 19, 2020, 22:07I have ordered one now. Looking forward to receive it. >:D >:D
Would have sold you mine for 320 :) hehe
Quote from: shnazzle on February 19, 2020, 22:17Quote from: Bugster_MR2 on February 19, 2020, 22:07I have ordered one now. Looking forward to receive it. >:D >:D
Would have sold you mine for 320 :) hehe
Too late. :p PPE? Used?
Quote from: Bugster_MR2 on February 19, 2020, 22:22Quote from: shnazzle on February 19, 2020, 22:17Quote from: Bugster_MR2 on February 19, 2020, 22:07I have ordered one now. Looking forward to receive it. >:D >:D
Would have sold you mine for 320 :) hehe
Too late. :p PPE? Used?
Hehe no was just kidding. it's a custom 200cell I had made. Cost a lot more than 320 I'll tell you that.
Just a sucker for a shiny Zero product hehehe
In voyeuristic mode here.
Happy watching from the side. Do like the look of that. Regardless of the pros n cons, I would not wrap it, looks too nice.
eagerly awaiting feedback
So I know there is a lot to say for wrapping against unwrapping. do I have the pros and cons right?
Pros = the system works better when the gasses are hot, it keeps engine bay temp down and thus reduces possible heat soak to inlet tract when the heat shield is removed.
cons = puts extra thermal stress on the unwrapped sections of the system and hides away your nice shiny new stainless system.
can the same question be asked for any section of the exhaust?
I don't want to wrap (Toyo manifold) but feel I have to. emailed Toyosport who said to wrap it.
You've answered your own question. It's more relevant & effective on the manifold & cat than the cooler silencer.
A lot of racing exhausts use a ceramic coating, - wrapping is the cheaper alternative. Interesting that Toyosport have said to do it.
I would agree. Wrap it. It's cheap enough and will last long enough for it to be worth it.
And quite frankly they generally have been quite solid so the steel used seems to cope well.
Has Kevin ever been persuaded to make a catback exhaust? I'm starting to dream about having a full Zero system fitted.
Quote from: steveash on February 20, 2020, 22:04Has Kevin ever been persuaded to make a catback exhaust? I'm starting to dream about having a full Zero system fitted.
Already asked him :)
Knowing my luck he'll decide to produce one ten minutes after I get one made down the road 😂
I've put an order in too, also managed to twist Kevin's arm to build me a back box too so I'll have a complete Zero system.
Dropping the car into him on the 26th May 👍🏻😀
Quote from: Amarlborough on March 2, 2020, 12:04I've put an order in too, also managed to twist Kevin's arm to build me a back box too so I'll have a complete Zero system.
Dropping the car into him on the 26th May 👍🏻😀
No way!
Oh man, I'm going to hate you.
Please make him make a jig for the exhaust.
@Amarlborough Are you local to him?
@shnazzle, had an email reply from Kevin.
He is happy to make something in the style of the malian race box I sent as a reference.
He needs the car as he builds it up insitu.
Made clear no pltns to create a jig or cat backs but happy to do one offs.
I may have finally found a reputable (localish) custom zorst company.
P D Gough. Nottingham.
Not really local, I'm Bedfordshire zeros in Kent so it's going to involve abit of travelling back and forth. ::)
Will need the car for a few days too.
Tried to offer my fitting as a template to make a jig, but he just isn't interested in developing it.
His argument is there are cheaper alternatives out there which he couldn't price match.
Quote from: Ardent on March 2, 2020, 17:45@Amarlborough
Are you local to him?
@shnazzle, had an email reply from Kevin.
He is happy to make something in the style of the malian race box I sent as a reference.
He needs the car as he builds it up insitu.
Made clear no pltns to create a jig or cat backs but happy to do one offs.
I may have finally found a reputable (localish) custom zorst company.
P D Gough. Nottingham.
Looking at their "Gallery" they have done some nice work for some nice cars. They may be towards pricey but reading what they offer that does include batch work that could help on the cost basis.
PS. And they do make from " patterns" of which they claim to have a large selection of. Likely not of a 2 " Zorst" but that they work from a pattern rather than an in situ build each time is noteworthy.
Planning to send them a similar email I sent to zero, complete with pictures to get idea and hopefully have a drive over Friday afternoon
8) Life is like a box of.......
I am very happy camper so far. Zero responded quickly to my emails, production and shipment was quick, packaging excellent, and the product looks amazing. Can't wait to install it. 🤠
Do let us know about the fitment and pics!
Received:
(https://i.imgur.com/YXtFEh7.jpg)
Cat used is high flow Magnaflow 59955 meeting Euro3 requirements.
Quote from: tom256 on March 27, 2020, 11:58Received:
(https://i.imgur.com/YXtFEh7.jpg)
Cat used is high flow Magnaflow 59955 meeting Euro3 requirements.
Certainly not cutting any corners there then
New Zero sport cat is assembled in my car now. Together with bigger and lighter alternator pulley. I have to say, it is really amazing. Car is much, much stronger, much more that I expected. My mechanic was also schocked. With Zero header it was mosty louder, with a little effect on performance but now I can feel much more power. Pricy, but worth every penny, I really recommend it.
My exhaust: Zero header + cat, TTE muffler.
Happy for you with the positive result.
Minor ´pity´ that you did the pulley and cat at the same time. The cat should be by far the most noticeable improvent though.
Anyway; congrats and ENJOY (which is the most important bit).
Well having just melted my nappy due to the "incredible" fit of my current sports cat I think it is time to bite the bullet, what is the best way of contacting Kevin?
Quote from: Mikeymead on May 10, 2020, 10:19Well having just melted my nappy due to the "incredible" fit of my current sports cat I think it is time to bite the bullet, what is the best way of contacting Kevin?
Give him a call or drop an email. He's definitely working.
sales@zeroexhausts.co.uk01233 822221
Quote from: shnazzle on February 18, 2020, 20:09I had a surprise email from our friend Kevin at Zero Exhausts; he now has perfect bespoke 200cell cat pipes for the mr2.
This is quite timely as I've just purchased a new MR2 Spyder and have been researching options for the exhaust tract. I've pretty much settled on a set of Zero Exhaust headers, and am leaning towards an HKS exhaust - but I hadn't yet found a solution for the downpipe. I was considering a couple of different options, but wasn't really sold on anything - until I saw this. Do you know if these are being sold off-the-shelf, or was it a one-off custom product?
Thanks!
Quote from: Bimmer-Bob on May 11, 2020, 00:42Quote from: shnazzle on February 18, 2020, 20:09I had a surprise email from our friend Kevin at Zero Exhausts; he now has perfect bespoke 200cell cat pipes for the mr2.
This is quite timely as I've just purchased a new MR2 Spyder and have been researching options for the exhaust tract. I've pretty much settled on a set of Zero Exhaust headers, and am leaning towards an HKS exhaust - but I hadn't yet found a solution for the downpipe. I was considering a couple of different options, but wasn't really sold on anything - until I saw this. Do you know if these are being sold off-the-shelf, or was it a one-off custom product?
Thanks!
Kevin builds them all to order so it's just a case of getting in the touch and putting the order in.
What he basically said is that he has created a jig for the MR2 for a stock-fitting sports cat.
And, once this lockdown is over I believe one of our members will be heading down to have a backbox designed and fitted. First full Zero exhaust system.
Quote from: tom256 on April 29, 2020, 23:13New Zero sport cat is assembled in my car now. Together with bigger and lighter alternator pulley. I have to say, it is really amazing. Car is much, much stronger, much more that I expected. My mechanic was also schocked. With Zero header it was mosty louder, with a little effect on performance but now I can feel much more power. Pricy, but worth every penny, I really recommend it.
My exhaust: Zero header + cat, TTE muffler.
a Dyno would be nice :p would be nice to know how this zero combo compares to stock.
Quote from: MR2Bart1991 on May 13, 2020, 10:11a Dyno would be nice :p would be nice to know how this zero combo compares to stock.
The stock header is not the only bottle neck, thus a dyno would not give you any info on the header swap unless the rest of the exhaust is opened up too.
The way to measure the header only would be a custom set up to the OEM header and thén swap the header.
Imo the way to look at a header swap on a 1ZZ is to see it as robbing less hp, not ádding.
Quote from: Petrus on May 13, 2020, 10:30Quote from: MR2Bart1991 on May 13, 2020, 10:11a Dyno would be nice :p would be nice to know how this zero combo compares to stock.
The stock header is not the only bottle neck, thus a dyno would not give you any info on the header swap unless the rest of the exhaust is opened up too.
The way to measure the header only would be a custom set up to the OEM header and thén swap the header.
Imo the way to look at a header swap on a 1ZZ is to see it as robbing less hp, not ádding.
Semantics. Let's call it "free up horsepower".
There's a fair bit of headroom in the stock exhaust. So dyno would (and historically has many times) pick up increases for sure.
There's been tons of dyno sessions with these kinds of setups and gains in general have been around 10-15hp.
It's more a case of where the torque curve ends up though. That changes per header, cat and backbox used.
What we don't have is a dyno for Zero header + Zero cat + TTE. Or really I guess Zero header + Magnaflow cat.
Quote from: shnazzle on May 13, 2020, 10:58Semantics. Let's call it "free up horsepower".
Semantics are key for understanding, in tuning even more than in politics ;-)
The 1ZZ vs 2ZZ per example is vastly different in the header topic. The crux being the flow of head of these two and how the header relates or not.
In the 2ZZ a bad header will cost a lot of hp, a good header will actually áid the filling.
The 2ZZ head is quite something imo. I would no doubt tack an
Engineered by Yamaha badge on it.
Bernie's was dyno tested at the various stages and highlighted the possible gains per component.
Quote from: Call the midlife! on May 13, 2020, 11:32Bernie's was dyno tested at the various stages and highlighted the possible gains per component.
Dug through the various specs&graphs here and spyderchat and concluded that the results are... confusing. Remap or not does not help clarify things.
The most clear red line I distinguished was the OEM manifold and cat being restrictive and the OEM intake being not (bar the intake horn).
It imo also illustrates the relative value of the absolute numbers. It is not all calibrated ;-)
Tried to find the dyno results of the MAF mod. again btw. Did not find them. If anyone knows where to find it, most obliged.
I have sofar stuck with the OEM intake horn and done all the mods in single steps.
Now mounted a not restrictive elbow with bell mount. Will need de-lockdown to try.
Quote from: Call the midlife! on May 13, 2020, 11:32Bernie's was dyno tested at the various stages and highlighted the possible gains per component.
From Robs extensive receipts and invoices after each mod car was Dyno'd
148 BHP
Exhaust & Sports Cat
157 BHP
Apexi ECU
Crower Cams
167 BHP
Zero Manifold
171 BHP PPE Induction
Quote from: Bernie on May 13, 2020, 12:37Quote from: Call the midlife! on May 13, 2020, 11:32Bernie's was dyno tested at the various stages and highlighted the possible gains per component.
From Robs extensive receipts and invoices after each mod car was Dyno'd
148 BHP
Exhaust & Sports Cat
157 BHP
Apexi ECU
Crower Cams
167 BHP
Zero Manifold
171 BHP PPE Induction
That doesn't help as still don't know if it was the cat or the exhaust :)
But, many accounts have noted a change in performance after swapping cat. No counts of performance for swapping just exhaust.
There are so many cars that have increased power output with the TTE. It would be interesting to see where the boundary is.
I'd like to think at about 200hp because take Matt's SP turbo system for example. To get from 200 to the SP240 he added the high-flow exhaust.
Same with 2zz. Lots have TTE with 2zz,so it's clearly good with no notable restriction to 190 (which they never run anyway).
Anywya... Would be good to see what Zero + Zero cat makes
Quote from: Bernie on May 13, 2020, 12:37From Robs extensive receipts and invoices after each mod car was Dyno'd
148 BHP
Exhaust & Sports Cat
157 BHP
Apexi ECU
Crower Cams
167 BHP
Zero Manifold
171 BHP PPE Induction
So with header, de-/sports cat and free flow muffler it would probably be some 155+ bhp.
Did you try the MAF mod too in some stage? or do I remember that incorrectly?
Quote from: shnazzle on May 13, 2020, 13:00No counts of performance for swapping just exhaust.
I did the decat ´Che´ clone header first, than the muffler, the decat pipe last.
No added power worth mentioning from just the header.
Muffler made the engine rev quicker from some 5K.
Decat made the engine stronger all over the range and rev quicker still.
No dyno méasurements.
Quote from: Petrus on May 13, 2020, 13:03Quote from: Bernie on May 13, 2020, 12:37From Robs extensive receipts and invoices after each mod car was Dyno'd
148 BHP
Exhaust & Sports Cat
157 BHP
Apexi ECU
Crower Cams
167 BHP
Zero Manifold
171 BHP PPE Induction
So with header, de-/sports cat and free flow muffler it would probably be some 155+ bhp.
Did you try the MAF mod too in some stage? or do I remember that incorrectly?
No MAF mod carried out
Quote from: Bernie on May 13, 2020, 13:15Quote from: Petrus on May 13, 2020, 13:03Did you try the MAF mod too in some stage? or do I remember that incorrectly?
No MAF mod carried out
Thank you.
Then it was another owner who first tried the MAF mod and later also a cam change.
At the end of the day without pre and post mod dynoes it's all subjective anyway.
Bum dyno proves nothing.
I know what my last dyno readout was but can't say what the actual gains were as I didn't have a pre mods dyno.
The law of averages suggests I probably had no more than 120bhp before starting with an 18 year old, worn motor. On that assumption I maybe added 30bhp with the work I did but that's also suspect as it was blowing oil out of the OCV filter housing on the dyno so possibly not reaching peak performance.
The mid range performance gains are enough for me to consider it worth the effort, at some point in the future there'll be an exhaust change and another visit to Greggs. (Not for meat pies)
Quote from: Call the midlife! on May 13, 2020, 13:25At the end of the day without pre and post mod dynoes it's all subjective anyway.
Bum dyno proves nothing.
Use the virtual thing app on the mobile but that too uses the same thing as the bum; acelleration and acc. differences.
A bit more objective and as such accurate but for comparative purposes on the same car, same circumstances only.
Also correct about the before and after of dyno measurements.
The up side is that the power side of things is not the crux of our MR :-)
It even has a hard measurable up side: The nimbleness; the weight, is easily objectively ascertained.
Well i just want to know how a full zero setup, header + zero sportcat would compared to something like the PPE or MWR combo as these 3 setups are the best options for the 1zz at this moment as far a i know, i know peak power won't really increase that much n/a but really curious for the full powerband difference.
Quote from: MR2Bart1991 on May 14, 2020, 08:44Well i just want to know how a full zero setup, header + zero sportcat would compared to something like the PPE or MWR combo as these 3 setups are the best options for the 1zz at this moment as far a i know, i know peak power won't really increase that much n/a but really curious for the full powerband difference.
Definitely interesting. The Zero isn't 100% equal length, whereas the PPE is from what I can see. And the PPE has much more narrow runners and waaaayyy longer.
The MWR (CHE), ToyoSport, Hamish, etc etc are all just copies of thr stock manifold minus the pre-cats so I wouldn't expect any gains aside from the gains of not having the pre-cat Chambers, if that makes sense. Hence why nobody ever really feels that much difference. The restriction is removed but the "flow" is the same. Just more of it.
The Zero and PPE are "tuned" manifolds. In other words, they offer benefits other than just the benefits of not having the pre-cat chambers. They change the way the engine breathes.
We need a dyno day is what we need...
Best would be a couple of dyno days with two or three cars, each going through a series of mods. Very time-consuming.
Quote from: shnazzle on May 14, 2020, 09:53Quote from: MR2Bart1991 on May 14, 2020, 08:44Well i just want to know how a full zero setup, header + zero sportcat would compared to something like the PPE or MWR combo as these 3 setups are the best options for the 1zz at this moment as far a i know, i know peak power won't really increase that much n/a but really curious for the full powerband difference.
Definitely interesting. The Zero isn't 100% equal length, whereas the PPE is from what I can see. And the PPE has much more narrow runners and waaaayyy longer.
The MWR (CHE), ToyoSport, Hamish, etc etc are all just copies of thr stock manifold minus the pre-cats so I wouldn't expect any gains aside from the gains of not having the pre-cat Chambers, if that makes sense. Hence why nobody ever really feels that much difference. The restriction is removed but the "flow" is the same. Just more of it.
The Zero and PPE are "tuned" manifolds. In other words, they offer benefits other than just the benefits of not having the pre-cat chambers. They change the way the engine breathes.
We need a dyno day is what we need...
Best would be a couple of dyno days with two or three cars, each going through a series of mods. Very time-consuming.
I agree with everything you say, but the new MWR combo is more of a PPE copy now though (https://www.monkeywrenchracing.com/wp-content/uploads/2020/02/MWR-707215-1-mwr.jpg)
this is how the MWR combo looks now.
Quote from: MR2Bart1991 on May 14, 2020, 10:14Quote from: shnazzle on May 14, 2020, 09:53Quote from: MR2Bart1991 on May 14, 2020, 08:44Well i just want to know how a full zero setup, header + zero sportcat would compared to something like the PPE or MWR combo as these 3 setups are the best options for the 1zz at this moment as far a i know, i know peak power won't really increase that much n/a but really curious for the full powerband difference.
Definitely interesting. The Zero isn't 100% equal length, whereas the PPE is from what I can see. And the PPE has much more narrow runners and waaaayyy longer.
The MWR (CHE), ToyoSport, Hamish, etc etc are all just copies of thr stock manifold minus the pre-cats so I wouldn't expect any gains aside from the gains of not having the pre-cat Chambers, if that makes sense. Hence why nobody ever really feels that much difference. The restriction is removed but the "flow" is the same. Just more of it.
The Zero and PPE are "tuned" manifolds. In other words, they offer benefits other than just the benefits of not having the pre-cat chambers. They change the way the engine breathes.
We need a dyno day is what we need...
Best would be a couple of dyno days with two or three cars, each going through a series of mods. Very time-consuming.
I agree with everything you say, but the new MWR combo is more of a PPE copy now though (https://www.monkeywrenchracing.com/wp-content/uploads/2020/02/MWR-707215-1-mwr.jpg)
this is how the MWR combo looks now.
Eh? MWR made a copy or tye PPE?
They are selling both on their site right now yeah (https://scontent-bru2-1.xx.fbcdn.net/v/t1.0-9/97187209_2979973785379371_2628645716024623104_o.jpg?_nc_cat=111&_nc_sid=0be424&_nc_ohc=ARi1qmGYpYQAX_V6rQS&_nc_ht=scontent-bru2-1.xx&oh=f7a29a568d089f87ed34afd9d59726e6&oe=5EE11D79)and looks like a copy to me.
Quote from: MR2Bart1991 on May 14, 2020, 10:28They are selling both on their site right now yeah (https://scontent-bru2-1.xx.fbcdn.net/v/t1.0-9/97187209_2979973785379371_2628645716024623104_o.jpg?_nc_cat=111&_nc_sid=0be424&_nc_ohc=ARi1qmGYpYQAX_V6rQS&_nc_ht=scontent-bru2-1.xx&oh=f7a29a568d089f87ed34afd9d59726e6&oe=5EE11D79)and looks like a copy to me.
Well jeez.
I'm starting to feel like a dinosaur on this forum. Things are changing quicker than I can keep up
Quote from: shnazzle on May 14, 2020, 09:53The MWR (CHE), ToyoSport, Hamish, etc etc are all just copies of thr stock manifold minus the pre-cats so I wouldn't expect any gains aside from the gains of not having the pre-cat Chambers, if that makes sense. Hence why nobody ever really feels that much difference. The restriction is removed but the "flow" is the same. Just more of it.
The Zero and PPE are "tuned" manifolds. In other words, they offer benefits other than just the benefits of not having the pre-cat chambers. They change the way the engine breathes.
The crux is in understanding what ´tuning´ means. It means that the lengths of the runners and the way they collect in such a way that the pressure waves arrive at the exhaust valve at the moment that they assist in max filing of the combustion chamber.
This can be through the scavenging effect of a negative wave or the pushing back through a positive wave.
This occurs only at specific revs as only at those the travel time of the waves coincide with the valve timing.
The down side is that the wave also arrives in the wrong phase at the wrong moment.
I.e. tuning the harmonics very much like a musical instrument.
Equal length 4-1 has all the cilinders bounce at the same time, maximising the + and - pressure.
4-2-1 doubles the frequency at half the pressure of 4-1.
Now the last aspect is the interference of the positive and negatives of the wave itself. That too is tuned by the lengt of the runners.
The shorter the runners the higher the frequency of the bouncing as the length the waves travel is shorter but there can be only very limited interferencing.
The longer the higher the amplitude can get but the frequency obviously goes down.
Unequal length primaries in a 4-2-1 can be deliberately tuned as well. It will again smoothe the effect over a broader rev range.
The ham question is
´tuned for whát?´ The extemes beingmore but ´peaky´ and less but ´wide´.
The OEM runner design is tuned too. You can safely assume that this is by far the most researched tuning of all on the market.
The runners are designed to give the broadest power band. It´s scavenging/loading effects are such that they have the least negavive effect and thus also lower positive effects.
Copying of the same design sans precat is a safe approach.
Collector design is paramount too as it determains how and how strong the wave bounces but that is just mudding the water in this case.
Suffices to say that the dedicated designs of PPE and Zero are superior. The effect is stronger; the positive and negative more pronounced.
This is where copies often miss the plot. Not all copies are the same and it pays to have a good look there.
With OEM cat the effect of a better manifold will be less than with a sports cat or decat.
If the Zero manifold would have been easily available at the time, I would have gone for it as I planned to go free breathing. As it is I have a Che clone with the positive side effect being the widest/flattest possible torque hump.
All in all ´tuned´ means that you can choose your poison.
....and now we can throw wrapping the runners into the equasion.
The speed of the pressure waves increases with increase in gas temp. = affects the tuning of the header.
Ergo wrapping affects the tune.
Quote from: shnazzle on May 14, 2020, 10:34Well jeez.
I'm starting to feel like a dinosaur on this forum. Things are changing quicker than I can keep up
Welcome to my world. :)
Quote from: tom256 on April 29, 2020, 23:13New Zero sport cat is assembled in my car now. Together with bigger and lighter alternator pulley. I have to say, it is really amazing. Car is much, much stronger, much more that I expected. My mechanic was also schocked. With Zero header it was mosty louder, with a little effect on performance but now I can feel much more power. Pricy, but worth every penny, I really recommend it.
My exhaust: Zero header + cat, TTE muffler.
got a sound clip of your combo by any chance?
Installed my Zero cat today. Bolt on easy install. Great fitment. New gaskets and new hanger came with the cat.
I have the oem silencer and an unknown aftermarket header without precats already on the car. If I had known my cheap header had a 35mm inner diameter, I would have ordered the Zero manifold too, since the Zero cat pipe has 44-45mm inner diameter. ::)
Very small change to the sound and no more noise than the stock cat.
Feels a little less restricted at high revs.
Nice small improvement. Guess I would need the full system to have more gains. Anyway, I am very satisfied.
Rear shot.
Tidy.
Quote from: Bugster_MR2 on May 19, 2020, 19:45Rear shot.
Go for full exhaust mod.
Firstly I bought TTE muffler, and there was minor difference (mosty cool sound), later I bought Zero mainfold. I mas dissapointed with minor difference, mainly more louder and very sporty sound when You rev engine. Now after buying Zero cat difference is huge and I'm clearly feel the difference. Engine sound more like rally car. I was calling today tuning workshops to dyno the car, but everything is closed.
Maybe next week.
The question is now, if muffler with more flow will change anything.
That Zero downpipe looks great. It has all of the features you want on both ends to stop leaks.
That MWR 4 into 1 might actually be the OBX Chinese header that is available on EBay. It's believed to be a copy of the PPE but not a good copy.
OBX Racing Header (https://www.ebay.com/itm/OBX-Racing-Stainless-Header-For-2000-2005-Toyota-MR2-Spyder-1-8L-DOHC/133400078159?fits=Model%3AMR2+Spyder&epid=558486031&hash=item1f0f43a74f:g:SgwAAOSw1PxeQvqT)
There have been several variants of various performance downpipes throughout the years. They have been shown to produce on a dyno with before and after in the range of 8-10whp for the 1ZZ. It is a real power adder compared to other modifications.
I have the cheap Chinese version but its problematic in terms of the flanges that leak so I had to modify mine to get it to work.
Did some thread cleanup for non-cat chatter.
Keep it on-topic (including myself in that)
Quote from: Dev on May 23, 2020, 14:50That Zero downpipe looks great. It has all of the features you want on both ends to stop leaks.
That MWR 4 into 1 might actually be the OBX Chinese header that is available on EBay. It's believed to be a copy of the PPE but not a good copy.
OBX Racing Header (https://www.ebay.com/itm/OBX-Racing-Stainless-Header-For-2000-2005-Toyota-MR2-Spyder-1-8L-DOHC/133400078159?fits=Model%3AMR2+Spyder&epid=558486031&hash=item1f0f43a74f:g:SgwAAOSw1PxeQvqT)
There have been several variants of various performance downpipes throughout the years. They have been shown to produce on a dyno with before and after in the range of 8-10whp for the 1ZZ. It is a real power adder compared to other modifications.
I have the cheap Chinese version but its problematic in terms of the flanges that leak so I had to modify mine to get it to work.
Well i thought the chinese obx one had the 02 sensors at the wrong place, the mwr one has it at the correct place like the PPE now, also the oxb one only sells a not catted downpipe so i'm not sure if mwr now makes their own or they just take the obx one and correct the o2 sensors and or fit a high flow cat.
Quote from: MR2Bart1991 on May 24, 2020, 08:51Quote from: Dev on May 23, 2020, 14:50That Zero downpipe looks great. It has all of the features you want on both ends to stop leaks.
That MWR 4 into 1 might actually be the OBX Chinese header that is available on EBay. It's believed to be a copy of the PPE but not a good copy.
OBX Racing Header (https://www.ebay.com/itm/OBX-Racing-Stainless-Header-For-2000-2005-Toyota-MR2-Spyder-1-8L-DOHC/133400078159?fits=Model%3AMR2+Spyder&epid=558486031&hash=item1f0f43a74f:g:SgwAAOSw1PxeQvqT)
There have been several variants of various performance downpipes throughout the years. They have been shown to produce on a dyno with before and after in the range of 8-10whp for the 1ZZ. It is a real power adder compared to other modifications.
I have the cheap Chinese version but its problematic in terms of the flanges that leak so I had to modify mine to get it to work.
Well i thought the chinese obx one had the 02 sensors at the wrong place, the mwr one has it at the correct place like the PPE now, also the oxb one only sells a not catted downpipe so i'm not sure if mwr now makes their own or they just take the obx one and correct the o2 sensors and or fit a high flow cat.
I had a look again and compared the both. I can now some some features that are different particularly the shape of the flange. Its probably their own.
just finnaly decided to get rid of my Decat and to order one of these, looks like you just can't go wrong with a zero.
So for the guys that got one of these how long did it take from ordering one to receiving one?
From paying to receiving in Poland it was 2 weeks. So expect around 1 week within UK.
Around 2 weeks iirc.
Got my exhaust today just needs a little fix though.(https://scontent-bru2-1.xx.fbcdn.net/v/t1.0-9/103736479_3055795117797237_5983714597348167259_n.jpg?_nc_cat=110&_nc_sid=0be424&_nc_ohc=qroOicUTea4AX-Yj9R8&_nc_ht=scontent-bru2-1.xx&oh=0e3eb273767de37497bf16a1e4bab057&oe=5F080C89)
Some shininess from Kent arrived at the workshop this morning!
Zero 1.jpg
Zero 2.jpg
Quote from: Mikeymead on July 6, 2020, 20:01Some shininess from Kent arrived at the workshop this morning!
Zero 1.jpg
Zero 2.jpg
I've never seen them together.
That looks hot.
Now imagine a nice backbox to go with that....
Fitting a whole system tomorrow, wish me luck.
Job done.
https://www.mr2roc.org/forum/index.php?msg=828340
Well done Mikey, brilliant job you've done there, looks well smart.
That's one of the neatest installations i have seen, well done, far beyond what i am capable of.
Quote from: Rushy67 on July 12, 2020, 22:22That's one of the neatest installations i have seen, well done, far beyond what i am capable of.
Thank you for your praise but it's only bolting tubes together, it helped that they fitted nicely, real praise should go to the manufactures for making a decent product.
@Mikeymead Any idea when you will get to run it?
@ Ardent
Already have Jase, had a nice topless drive out with the lady wife yesterday, sound is similar to the old system but a bit quieter.
Quote from: Mikeymead on July 6, 2020, 20:01Some shininess from Kent arrived at the workshop this morning!
Zero 1.jpg
Zero 2.jpg
This just looks so Beautifull! :D any plans for Dyno run? (and soundclip)
Quote from: Mikeymead on July 12, 2020, 19:41Job done.
https://www.mr2roc.org/forum/index.php?msg=828340
That looks like a piece of art!
One for the wishlist...
This looks very good quality. Has anyone bought the heat shield as well ?
Quote from: toyoda on November 26, 2020, 22:10This looks very good quality. Has anyone bought the heat shield as well ?
There's at least one that I know of but I believe he stopped producing them due to a bit of a design flaw.
Rob had the very first one made by Zero and had the heat shield and its still fine
9DF99038-5E50-4BB0-968E-51FE6BFB59DB.jpeg
Would like to think that pic will still confuse a few, as it did me when I first saw it.
I've just put in a request to Kevin for one of his cats.
Quote from: Ardent on November 27, 2020, 23:56Would like to think that pic will still confuse a few, as it did me when I first saw it.
Yep poor Bernie hit hard times when it came to replacing his heat shield and had to fashion one out of an old garage door!
:))