6G Celicas Forums

just because one car is running 20psi and another car is running only 15 or 16 doesnt nessicarly mean the one pushing more boost is putting out better numbers...theres a million and one factors that go into it, size of the turbo, octane, tune, all sorts of factors...i understand your saying that the block can handle it..but 1) the ct20b is limited to how many pounds you can put through it effiecnetly and reliably before it explodes and 2) its going to kill the life of the turbo the more pounds you put through it unless you plan to upgrade it sometime in the near future...i think that 18-19 for daily driving on a ct20b is perfect...now yes, you may be able to turn it up a couple more but as stated above your going to have knock problems, and honeslty is it really worth it for a couple more pounds? your better off just enjoying 18 psi untill you can afford to upgrade to bigger turbo and put out some better numbers more reliably...just my 0.02

They are not slow to catch on to some 20psi crazy thats going on..lol.
The simple fact is that those cars run much larger turbo's then the ct26 or ct20b.
Stock evo runs 20psi from the factory. It comes with a huge td06 20g turbo, and that whopping 20psi amounts to about 250hp at the wheels.
As for the supras pushing big boost, they have all upgraded to massive single turbo's to be able to safely make that kind of boost.

This post has been edited by lagos: Jan 2, 2009 - 12:18 AM

your also forgetting these guys are running race fuel jim
are you planning on filling your tank with 110?

anybody who tells you they are daily driving @ 29psi, on pump fuel, is a liar.

Ok......I fully understand the difference between pressure (psi) and airflow, so for those questioning it, I get it. In fact I have first hand experience with it.....Shannons 5s made the same hp as Mannys 5s at 5psi less boost.......because of a more efficient turbo and better airflow.

No, I dont plan on running race gas. But I do plan on turning up the boost until I see knock, and then dial it back for safety.......which should be quite a bit down the road from 18psi. Just for a quick example, look at califcarm. He is running 20-21psi on his Daily driver with a ton more ignition advance than I will have. In fact he states he wished he went with a stronger "Helper Spring" to run more boost and less igniton advance to achieve the same Hp number.

I wont go at this blindly, I will have it done on the dyno. I do like you idea of installing a knock detection for now tho. It will give me a warning for in case I see knock later on. I will take it as far as I can safely, and leave it at that. I cant see it being detrimental to run an extra 3-5psi. Stock GEN3's run 18psi all day long WITHOUT Water Injection......I HAVE Water Injection, so if stock GEN3's dont see knock at 18psi without water injection, I believe I can run 21-22 psi without seeing knock. We will find out soon enough.

Basically, 21-23 psi is just a number. I dont HAVE to run this numbers...and I WILL NOT run these boost levels if knock is present. The biggest factor here that will determine the amount of boost I will be running safely, WILL BE KNOCK. Realistically, If I see 22psi with no knock present......I will leave it there.

Anything much past 1.2bar (17psi) and the ct26c2 (ct20b) is just a hot air blower...you`ll suffer knock like theres no tomorrow.

I doubt you manage to get no knock above 20psi even with water injection.

I have never seen a stock 3rd gen run 18psi ever on a regular basis, and I have seen more than my fare share of GT4`s.

Link do a knock sensor for £90 thats quite good...worth considering

Keep in mind that Califcarm is injecting around 1400cc of pure alcohol to run that boost level, and also has a JS knock guard (way better then the turboxs knock lite). The only reason he is running that much ignition advance is because at 1400cc he has to tune out a lot of the pump gas because the car will just fall flat on its face from being too rich.
I talk to him via pm often and he also expressed to me that he did end up running into detonation issues over time and has since turned the boost down a bit from what it was.

There have also been plenty of 3rd gen guys who blew their ring lands at 18psi on a stock motor. So just be careful.

I believe Emily Hux runs 17psi daily on her Grellow car w/93 Octane. (Stock Gen 3, Intake, Exhaust, Side Mount)

That, or just plain "asking for it"! lol

Here is a good question I just thought of...
Jim, you went from a 2nd gen with ct20b to a 3rd gen with the same turbo. The two motors are basically the same with the exception of the 3rd gen having a more aggressive factory cam setup and a map based efi system. How would you compare the power difference having owed both? Was it fairly similar to the 2nd gen in terms of WOT power? How about throttle response and boost lag?

Id love to hear a detailed comparison between the two engines.

Actually, the Gen 3 head is a whole different breed. 3 Angle valve job, revised valve angle, larger ports (more comparable to a DSM), more efficient manifolds (intake and exhaust) and a shim-under-bucket upgrade. Otherwise, the obvious being the larger injectors, re-vamped turbo and compression ratio.

Correct me if I'm wrong, but the Gen 3 should essentially out-flow the "CT20b" sooner than the Gen 2; in a basic assumption based upon efficiency. *shrug*

Ok, thanks for the concerns....and I am well aware of Califcarms J$S knock detection system, I too talk to him a regular basis.

Nial.....I am sure you have seen your fair share of GT4's, you seem very into it based on previous posts. Obviously based on HUX and ATS's testing, the CT20B does in fact still make power above 18psi. Not quite as much as per PSI as say it did 12psi due to going outside its efficiency range, but STILL making power.

As far as cracking ring lands at 18psi......this is on a CT20b, or an upgraded turbo? Mr2 or GT4? I have seen MANY posts and dyno plots of GEN3's at or above 18psi.....and steadily more and more above 20psi. So for those cracking the ring lands at 18psi, there must have been some reason other than being the fact they were running 18psi on a CT20B. If most of the cars that cracked ring lands at 18psi were MR2's, it might very well be due to the lack of there ability to have an efficient intercooler.....especially if "most" of these cars were cracking ring lands before Water Injection became as popular as it is. Its all but law that the stock longblock can handle 18+psi (yes 18psi of pressure, not air flow so thats not confused here again), and the amount of airflow that the CT20b can flow isnt a concern for running lean on a stock GEN3 ecu......so the only thing that is probably cracking these ring lands is knock. I dont know, these are all just guesses, but we will see what happens when I am able to strap it down to the dyno......If it knocks above 18psi, I will surely let you all know, if it doesnt I will be sure to reply just the same. I will definitly let you know how I made out.

Good question Art. The problem is I cant really compare WOT runs because I had 2 different tranny setups in the car and it made a HUGE DIFFERENCE in how the car feels. I had the GEN2 with CT20B at 17psi, with a NON-LSD E153. It made the car "feel" faster at WOT then my current setup because of all the torque steer. As for your day in day out driving, the new setup is definitely better......but certainly not "worlds" better like I have read so many times before. The biggest difference between the GEN2 and the GEN3 that I feel, is the throttle response. Its VERY crisp. The car definitely seems to pull harder all the way to redline then the GEN2. The car feels much smother in every aspect. As for a "detailed" comparison between the too, like I said its hard to due because of the 2 different trannys

Ah good... so this probably explains the differences pretty well. The 2nd gen seemed faster (probably from the torque steer), but didn't pull as well up top, and the throttle response was better on the 3rd gen.

So its interesting to know that the two setups are very similar when compared to each other. A lot of the throttle response probably has to do with the top mount ic having a shorter path then your old front mount, as well as the map sensor actually monitoring intake manifold pressure. The more power up top is probably due to the changes with the cams/head.

One could probably see similar benefits in their 2nd gen by converting to gen3 electronics and swapping in a 3rd gen intake cam along with a retarded cam gear on the stock exhaust cam.

This post has been edited by lagos: Jan 2, 2009 - 8:23 PM

I would say so.

driving a second gen and the third gen the diffenence is night and day

Hmmm - wouldn't happen to be a certain yellow MR2T from Houston who is known for being an extreme liar would it?
If so - the way he told it [standing over his engine bay with me] it was on a CT-20b

And I did call BS

This post has been edited by DEATH: Jan 14, 2009 - 10:56 AM

Here is a pics of the helper spring I installed. I tested the factory actuator without the spring installed with my air compressor to see how far the "flapper arm" traveled at different boost pressures. At 9-10psi it opened about a 1/4 of the way, and at 14-15psi it traveled to its furthest point, "completely open" I had to play around with the spring a bit to get the tension that I wanted. I finally settled on it having the same travel at 14psi with the helper spring as it did at9psi without it. It now travels about 1/4 of the way open at 14psi. It takes as much as 22-25 to fully open the wastegate "door" now.



Here are a few pics of the Anti-lag stuff





And a few shots of inside the exhaust manifold, showing more of the Anti-lag





When the weather breaks, I will get some pics up of the car with the New WRC blocks.

This post has been edited by _Jim_: Jan 20, 2009 - 10:11 PM

looks good jim...good luck with it...anyone care to explain how exactly the anti-lag system works so i have a better understanding of it?

Just one question......dosnt this increase the problem with over boosting/boost spikes????

No, it wont increase over boosting/boost spikes, in fact....I shouldn't see any. I would think the problem with over boosting is the wastegate is trying to bypass more exhaust gas/energy then the "flapper door" will allow. I plan on running at or above 20psi, so most of the exhaust gas/energy will be going past the turbine blades and down the exhaust, and very little bypassed via the wastegate. The purpose for adding the helper spring is because there is so much force on the wastegate "flapper" that it get prematurely blow open BEFORE the desired boost level is reached.

Here are some updated pics with the blocks for your enjoyment.