Sports cats

[treeroy]

What are people's thoughts on sports cats?

I can't find too many posts/threads from people who have sports cats fitted.

If anyone has experience to share about:
- passing MOT / engine light
- sound
- performance

It would be great to hear!

Thanks

[Call the midlife!]

Decent 200 cell cat on a good engine shouldn't give any issues at mot time.
BUT... pretty much a waste of time and money if you're running rough and/or don't open up the manifold/cat back.
Will increase flow and noise as part of a complete, free flowing system.

[treeroy]

Decent 200 cell cat on a good engine shouldn't give any issues at mot time.
BUT... pretty much a waste of time and money if you're running rough and/or don't open up the manifold/cat back.
Will increase flow and noise as part of a complete, free flowing system.

My car runs fine. (in fact i've got no idea what people mean by "running rough", never experienced it)

It's standard currently.

I am intending to get a custom catback exhaust made. Looking at getting it done by Tony Banks Exhausts. They also do cats and say they can fit a sports cat (i presume 200cell) too, and I kind of think 'in for a penny, in for a pound'.

But I don't know how easy it is to pass MOT with sports cat on this engine.

What's wrong with stock manifold? And what can you upgrade to? The manifolds I can find on ebay look pretty standard. I want to replace the manifold to get rid of the pre cats, but not sure what to get. I know people on here say they have Toyosports manifolds but I can't find that anywhere. The only dedicated aftermarket one that's non-ebay-special is Zero Exhausts and that's £400 which i would not be willing to pay.

[1979scotte]

Not much point unless going forced induction or for a stand alone ecu.
Never had a problem passing mot with 200 cell wouldn't chance 100.
Needs to be hot hot hot.

[Carolyn]

Toyosports does them in batches.  so they don't seem to be available right now.  There is this one, which seems pretty much the same -though I'd have to inspect one to know for sure:

https://www.ebay.co.uk/itm/STAINLESS-EXHAUST-MANIFOLD-SPORT-FOR-TOYOTA-MR2-MR-2-MRS-W30-ROADSTER-1-8-00-07/153568997571?fits=Model%3AMR+2%7CPlat_Gen%3AMK+III&hash=item23c16cf0c3:g:tF0AAOSwsKFfKqbp

Edit:  You get what you pay for in the exhaust department.  I am on my second Toyosports - they do crack eventually.  I've handled and fitted a Zero ,and they are top quality and worth the money if you can afford them

[shnazzle]

An eBay search for mr2 manifold will produce one. Cheap and cheerful. Might crack in a few years but for the price...

Difference between a Zero and an ebay; Zero had dyno proven performance increase. EBay has none. But, it doesn't reduce performance so it's still a good buy.

As for sports cat; the mod that has made the most noticeable power gain. Although I did get it the same time I got the Zero.

Noise increase definitely with a sport cat. No doubt. Definitely louder.

[Call the midlife!]

By "running rough" I mean anything away from normal running with decent fuel trims and combustion. You could always fit a 400 cell if you're concerned about the emissions test.
There's nothing "wrong" with the standard manifold but the purpose of the lower cell "sport" cat is to improve flow so a better flowing manifold will be a good idea.

[treeroy]

Toyosports does them in batches.  so they don't seem to be available right now.  There is this one, which seems pretty much the same -though I'd have to inspect one to know for sure:

https://www.ebay.co.uk/itm/STAINLESS-EXHAUST-MANIFOLD-SPORT-FOR-TOYOTA-MR2-MR-2-MRS-W30-ROADSTER-1-8-00-07/153568997571?fits=Model%3AMR+2%7CPlat_Gen%3AMK+III&hash=item23c16cf0c3:g:tF0AAOSwsKFfKqbp

Edit:  You get what you pay for in the exhaust department.  I am on my second Toyosports - they do crack eventually.  I've handled and fitted a Zero ,and they are top quality and worth the money if you can afford them

Thanks. Yes I've seen that on ebay. What I'm asking is what is the advantage of having an ebay manifold vs the stock one. Other than it having no precat.

[Carolyn]

Toyosports does them in batches.  so they don't seem to be available right now.  There is this one, which seems pretty much the same -though I'd have to inspect one to know for sure:

https://www.ebay.co.uk/itm/STAINLESS-EXHAUST-MANIFOLD-SPORT-FOR-TOYOTA-MR2-MR-2-MRS-W30-ROADSTER-1-8-00-07/153568997571?fits=Model%3AMR+2%7CPlat_Gen%3AMK+III&hash=item23c16cf0c3:g:tF0AAOSwsKFfKqbp

Edit:  You get what you pay for in the exhaust department.  I am on my second Toyosports - they do crack eventually.  I've handled and fitted a Zero ,and they are top quality and worth the money if you can afford them

Thanks. Yes I've seen that on ebay. What I'm asking is what is the advantage of having an ebay manifold vs the stock one. Other than it having no precat.

Not a lot - unless you've knocked the cats out of the cans - then the tubular manifold will give better performance.

[treeroy]

@Carolyn  sorry but what's a Tubular manifold? You mean if I remove the precat then the stock manifold is best?

I intend on having the precats removed just for my peace of mind. So either remove them from current manifold or get an aftermarket manifold.

[Carolyn]

@Carolyn  sorry but what's a Tubular manifold? You mean if I remove the precat then the stock manifold is best?

I intend on having the precats removed just for my peace of mind. So either remove them from current manifold or get an aftermarket manifold.

Knocking out the pre-cats will leave your engine blowing into two big empty cans, which will not perform as well as an aftermarket 'tubular' (made from tubing) one. 

It's all small differences - but they do add up.

[Petrus]

There is a bit of a mixed bag when looking at exhaust changes because the exhaust is like a chain with the cat being the most restrictive link.
So swapping the OEM manifold for ány tubular will net yiu te same restriction.
That observed, a gutted OEM manifold introduces undesireable harmonics so will be ever so slightly wórse.

With a less restrictive cat the manifold and muffler become more critical. A cheaper aftermarket maifold will flow better than the OEM one and will be sufficient till you hook ip a réally free flowing muffler.

I have fitted a cheapish one with good brackets to the engine block and the fixtures for the OEM heatshields. For the cheapest of manifolds heat wrapping is quite an extra stress ánd I prefer the heat shield to wrapping anyway.

[Bugster_MR2]

Spend your money on Zero manifold and racecat. Excellent quality.

[InnerStaytes]

Absolutely agree. As Carolyn says " you get what you pay for in the exhaust department". Zero may cost more than most other systems, but they are value for money. No question.

[Call the midlife!]

I've said this before but it bears repeating (and I've got a Zero manifold myself) if you're not changing anything but the exhaust system for a bit of extra flow then just buy a Toyosport for the £120 or whatever and see how long it lasts. 
If you only get 3 or 4 years out of it then just buy another and you're still not out of pocket, if you get 10 years then all the better.

[InnerStaytes]

I hear what you're saying, but I'm of the "do it once and do it the best you possibly can and hang the expense" brigade. If you come from a different stance (and experience tells me that there is a lot of value in that different viewpoint) then the (much) less expensive way has a lot going for it.

[Call the midlife!]

I hear what you're saying, but I'm of the "do it once and do it the best you possibly can and hang the expense" brigade. If you come from a different stance (and experience tells me that there is a lot of value in that different viewpoint) then the (much) less expensive way has a lot going for it.

Don't get me wrong I'm the same as you, all I mean is unless it's part of a major build with the associated investment then as we say in Yorkshire "it'll do..."

[treeroy]

I hear what you're saying, but I'm of the "do it once and do it the best you possibly can and hang the expense" brigade. If you come from a different stance (and experience tells me that there is a lot of value in that different viewpoint) then the (much) less expensive way has a lot going for it.

These cars are almost worthless, so unless it's absolutely essential work then I do not side with the "No expense spared" view.

My previous car I wanted to maintain properly, I bought it in June and spent £600 on doing up various things that weren't necessary fixes, but I wanted it to be done properly. Then a few weeks after, I crashed and wrote it off. Between me paying for the car and the insurance payout, I effectively lost 80% of the car's value, in two months. Plus losing that money I spent fixing it.

Bit of a wake up call to me. So I just want to spend the minimum required. Never know how long i'm gonna have the car. So no point on spending loads. If its cheaper to get the precats removed then why spend so much on a manifold? Especially one at £400 which will do the same job as a £120 ebay job. OK might last longer, but this is a 20 year old car, how long do u think the car's gonna last? You just dont know.

[shnazzle]

As I mentioned, they're not equal. Otherwise nobody would go for the 400 quid one. 
People like @stewart@boro have been tuning their Toyosport for at least 7 years.
Why choose that? Because gutting pre-cats isn't free (Labour, gaskets, time), it poses a health risk without proper PPE, and it causes an odd (barely noticeable) flat spot in power. 
120 quid gets you the peace of mind of no pre-cats without the flat spot. 
But gutting the stock manifold is "fine". 

Summary:
Cheapest - DIY gutting pre-cats, £25gbp approx for gaskets, tiny flat spot, peace of mind
Middle - DIY Toyosport, £150 with gaskets, no flat spot, no gains, peace of mind, luck of the draw quality. 
Top - DIY Zero, £425 (gaskets incl), proven increase in power, peace of mind. Life-time warranty 

Add another 30-60 for an o2 sensor that is likely to pack it in when you manhandle the manifold.

As for out lasting the car; unlikely. 
If you want to spend as little as possible on the car; leave the exhaust well alone. Maintain it well. Keep it on good tyres. Enjoy it while you've got it

[Call the midlife!]

I think you're mixing a few things up along the way, I'll gloss over the worthless part, a Zero manifold for £400 or so will do the same job as a £50 ebay manifold in the sense that it carries away exhaust gases.
But it will do it better because it's designed to do it better, so as we've previously discussed it all depends on the rest of your build and if it's worth the investment.
If you're classing your car as a worthless consumable then just leave the standard manifold as it is and drive it, it'll probably last long enough for your needs.
You're asking questions and we're giving you a full range of answers and options based on experience.
It's up to you how you choose to use the information.

[Ardent]

Cheapest - DIY gutting pre-cats, £25gbp approx for gaskets, tiny flat spot, peace of mind
Middle - DIY Toyosport, £150 with gaskets, no flat spot, no gains, peace of mind, luck of the draw quality.
Top - DIY Zero, £425 (gaskets incl), proven increase in power, peace of mind. Life-time warranty

Add another 30-60 for an o2 sensor that is likely to pack it in when you manhandle the manifold.

As for out lasting the car; unlikely.
If you want to spend as little as possible on the car; leave the exhaust well alone. Maintain it well. Keep it on good tyres. Enjoy it while you've got it

Post of the day.

[Ardent]

If you're classing your car as a worthless consumable then just leave the standard manifold as it is and drive it.

second post of the day.

[Petrus]

As I mentioned; the fixtures for the OEM heat shields are a thing not to overlook. For road use something to take into account in the decision process.

[tom256]

What are people's thoughts on sports cats?

I can't find too many posts/threads from people who have sports cats fitted.

If anyone has experience to share about:
- passing MOT / engine light
- sound
- performance

It would be great to hear!

Thanks

Zero cat should met Euro 4  standards (this what docs for Magnaflow cat says) for MR2 n/a.

High flow cat is louder, especialy if you connect it with Zero mainfold and TTE backbox. For me to loudy for longer journeys. That's why I'm waiting for Zero backbox.  But if You like loudy cars go for it. Sounds awsome.

For full performance benefits You need to replace mainfold and backbox. But it is worth, around 155hp is expected.  

[Bugster_MR2]

What some of you fail to inform about is the fact that Zero has a larger diameter tubing than the cheapo ebay stuff, so if you want a proper race cat you also need a proper header. Go Zero.