2zz vs 1zz 95 octane fuel

wilko59 · September 26, 2015, 09:52

Couldn't find anything on the forum search, sorry if this has been covered.

Anyway they 2zz seems to run exactly the same as the 1zz on 95 octane fuel. The lift comes in and sounds as it should but that aside the cars were performing exactly the same.

Sound about right?

JoeCool · September 26, 2015, 12:34

Not sure I quite follow you?

If the 2ZZ goes into lift, then it cannot be 'exactly the same as the 1zz'.

Both engines should run fine on 95 octane fuel, though the purist in me prevents me from fuelling the 2ZZ with 95 octane fuel: It's a high performance NA engine and designed for the Japanese market where 98 RON is standard. IMO it needs 98 RON. But if you choose to put 95 octane in it, it will just run a little down on power and with retarded ignition to prevent pre-detonation.

cabbydave · September 26, 2015, 12:51

Have you had a 1zz and a 2 zz side by side and tried this?

wilko59 · September 26, 2015, 15:07

Both side by side yesterday, several tests. I know the 1zz makes no difference with premium fuel but the 2zz ran identically to the 1zz in terms of pulling. Obviously we were shifting up at the same points or as close as we could. As I said the 2zz still went into lift when the revs were right but just didn't pull any differently. Premium fuel back in today and the difference is as you would expect.

shnazzle · September 27, 2015, 19:10

You'd have to make sure all other factors were equal. Tyres, wheels, total weight, does the 2zz have a decent exhaust/manifold setup?

As has been said on here, the 2zz rarely runs 190 ish if it's not optimised.

I reckon you can probably get a 2zz damn near the performance of a good 1zz if a heavier-set person drives it with a shoddy manifold and say, wider and softer tyres.
It's only a 50hp difference on a good day with max potential setup. Badly set up, call it 30hp.
Dunno, just my thought.

wilko59 · September 27, 2015, 20:15

Well funny you should say that. All sorts of tests. Fuel was defy an issue but as it turns out it seems the 2zz is restricted on the exhaust. The 1zz is decatted with a stainless manifold and standard air filter. The 2zz has a better located cone filter, stainless manifold but a stock pfl exhaust and cat - can't be good!

ChrisGB · September 28, 2015, 07:40

The stock exhaust costs 6bhp on the 1zz, so it won't do aa 2zz any favours. Exhaust manifold is very critical on 2zz as well. Most aftermarket ones rob the engine of power. It looks like the only ones that work are the PPE or adapted Celica manifolds.

Alex Knight · September 28, 2015, 08:45

Quote from: "JoeCool"It's a high performance NA engine and designed for the Japanese market where 98 RON is standard. IMO it needs 98 RON. But if you choose to put 95 octane in it, it will just run a little down on power and with retarded ignition to prevent pre-detonation.

You are wasting your money.

I assume you are using a Celica T-Sport/190 ECU? In which case, they are mapped for 95 RON UK fuel. The ECU will not pull timing on 95 RON fuel. A 2ZZ is never going to generate the in cylinder temperatures that require a better fuel with a higher knock threshold than 95 RON unless you use forced induction.

Also, not sure what pre-detonation is? I know of pre-ignition and detonation. Both are different things by the way.

Anonymous · September 28, 2015, 09:55

It's very hard to judge without seeing the cars and the results in real time like you have done.

But one thing that springs to mind that no has has directly said, Is how were the cars driven?

The 2zz is a funny engine in the way it needs to be driven, in comparison to the 1zz. If you don't have the car in lift and keep it in lift through the gear changes then it isn't being driven properly.

Also, what gearbox is fitted to the 2zz?

I'd be really interested to see how they compare actually. And once my car is running again I am hoping to catch up with Dasilver who has a k-swapped roadster

JoeCool · September 28, 2015, 10:22

Quote from: "Alex Knight"
Quote from: "JoeCool"It's a high performance NA engine and designed for the Japanese market where 98 RON is standard. IMO it needs 98 RON. But if you choose to put 95 octane in it, it will just run a little down on power and with retarded ignition to prevent pre-detonation.

You are wasting your money.

I assume you are using a Celica T-Sport/190 ECU? In which case, they are mapped for 95 RON UK fuel. The ECU will not pull timing on 95 RON fuel. A 2ZZ is never going to generate the in cylinder temperatures that require a better fuel with a higher knock threshold than 95 RON unless you use forced induction.

Also, not sure what pre-detonation is? I know of pre-ignition and detonation. Both are different things by the way.

I meant detonation.

And I honestly don't believe I am wasting my money. My fun cars do very limited milage and get driven hard. An extra couple of quid on a tank of fuel is the same in my mind as buying better oil. The additive packages in v-power/optimal do make a difference. I've had engines self cure little running faults with a couple of tanks of premium fuel irrespective of octane rating.

Interesting re the mapping though. Sure I read they were optimised for higher octane fuel but I suppose that could have been regarding Japanese spec cars.

Won't stop me running premium fuel though. It's not a waste if I feel the value from it.

jonty · September 28, 2015, 10:36

What exhaust manifold does the 2zz have? If it is Che, I bet that kills it, and along with not revving the hell out of the 2zz I would not be surprised if the 1zz/2zz are very close at lower rpm.

If I was trying to make this comparison I would start in 2nd at about 5k rpm... my brother and I did a few rolling runs in my 2zz MR2 and his S2000, and they were basically neck and neck from 40-70mph. We haven't had them side by side for a "more expansive" test, but I am certain the 1zz would have been nowhere near the S2k, whereas the 2zz will at least be able to stay in touch.

Jrichards20 · September 28, 2015, 11:22

Having had a very short drive of a 2zz, it would rape a 1zz from about 20mph onwards. (if revving to limiter on both).

wilko59 · September 28, 2015, 12:32

The 2zz has a 6 speeder in, I'm guessing from the Corolla 190 but would have to check. Likewise with the ECU. The 1zz has the standard fit 5 job.

jonty - I ran an S2000 for a while including a trip to the ring so I know it pretty well, I'd agree with you with the above.

The diferrences in gearboxes will make a difference, in so far as different shifting points, I've more experience driving my 1zz whereas my brother is new to the MR2. This only really gives me an advantage in the corners for now as he's a decent driver and knows when to shift.

I know the exhaust needs improvement, the manifold may be up to the task but will need to investigate. It's a stainless setup but not a cheapy eBay one like I've got in mine.

The 2zz is LeeH 's old build.

Lee H · September 28, 2015, 13:03

Manifold was a cheap eBay one when I built it. It also has a jdm ecu so might respond better to higher octane fuel. Gearbox is the corolla t sport one.

I actually got a S2000 straight after it and in my mind there is no comparison on performance. Can feel vtec doing something where lift is just mainly noise from my experience.

wilko59 · September 28, 2015, 13:10

Thanks Lee, I was going to contact you to find out about the manifold. Hope you're enjoying the S2000 they're very special I just needed the money for other things.

Cheers

Lee H · September 28, 2015, 13:20

Been trying to sell the S2000 as I prefer my other Roadster but no takers so far, no hardship keeping it I guess.

JoeCool · September 28, 2015, 13:35

Quote from: "Lee H"I actually got a S2000 straight after it and in my mind there is no comparison on performance. Can feel vtec doing something where lift is just mainly noise from my experience.

The 2zz in the corolla is certainly not just noise in lift. The increase in torque is noticeable - and you can really see it on the dyno too. It's not as manic as VTEC but it's certainly impressive.

I know you have a bit of a downer on the 2zz-ge, but there's no way 180+bhp in a car weighing less than a tonne should be slow. It's just ensuring that the engine is in fact performing to its potential with intake and exhaust...

jonty · September 28, 2015, 15:57

I think this basically confirms what I thought, that the Che exhaust completely knackers the power of the 2zz.

I took a colleague out for a spin in my car and he actually asked if I had not been at full throttle before we got to lift.. so I think that says how much of a noticeable kick it should be!

Wilco, if you are going searching for performance I would suggest that you look at getting a chopped Celica manifold and a free flowing rear system.

We still need this often mentioned 2zz dyno day sorted...

JoeCool · September 28, 2015, 16:30

Quote from: "jonty"I think this basically confirms what I thought, that the Che exhaust completely knackers the power of the 2zz.

I took a colleague out for a spin in my car and he actually asked if I had not been at full throttle before we got to lift.. so I think that says how much of a noticeable kick it should be!

Wilco, if you are going searching for performance I would suggest that you look at getting a chopped Celica manifold and a free flowing rear system.

We still need this often mentioned 2zz dyno day sorted...

Yes, all of this.

I've been driving my corolla T-sport around for 3 months so I know how the 2zz-ge performs. Actually they're not bad cars at all, they're certainly not slow but the handling amd balance just isn't there on a twisty Road. I clocked 16.1 seconds 1/4 mile on my first ever time drag racing, and there was another stock corolla T-sport that had made 16.0 dead when stock and was running 15.7's stripped of its interior. So that a decent benchmark to run the Mr2 against and check that it's a bit faster due to lower weight.

I'm going to be running an MWR manifold and stock exhaust initially just to get the car on the road, then look at better options without getting silly on cost or noise. So I'm well up for dyno'ing that configuration, knowing that my 2zz is healthy but may be restricted by the exhaust. I just hope it's not as restricted as the Che/eBay stainless manifolds seem to be!

Anonymous · September 28, 2015, 16:35

Rolling Road Day!! s:D

s:D

Jrichards20 · September 28, 2015, 16:35

I'm tempted to set one up for Feb when my engine is in s:)

s:)

wilko59 · September 28, 2015, 17:11

Well, just got back from work to find the rear end of the 2zz, its now sporting a can from a Jaguar XKR (supercharged), the sound is incredible but not built back up yet. It's a work in progress at the moment as we're pretty sure the manifold and possibly cat will need changing. How do I get pictures on here, do I have to use a hosting site?

Ardent · September 28, 2015, 17:29

Hosting site = yes.
If you have a blog page or anything put it there and link to it.

Anonymous · September 28, 2015, 17:55

Yes manifold and cat will be big restriction

mr2will · September 28, 2015, 19:05

Just been out in the MR2 with the xkr silencer sounds fantastic but no difference in power, Can a stock 1zz manifold really restrict the 2zz engine by 50hp seems hell of a lot to be add from adding a new manifold and removing the cat. I am disappointed with the car had a go in my brothers 1zz and felt it could do with a bit more power, so I purchased the 2zz presuming it would have the 190bhp, I haven't had it dyno yet but would expect the 2zz with the stock manifold to be only 5bhp more than the standard 1zz. Thinking there is another problem not confident that a manifold and cat removal can make another 50 hp. .

lee you mentioned when you did the conversion you said a waste of time were you also disappointed with the marginal power increase.

thanks

Willie