Not sure what your point is on that..... the stroker is included in the chart, it is the yellow line.

Keith

PS: 3400 RPM is right around where the stoker passes 5 psi. I notice that on my car 5 psi is the "noticable" start of making real power.

 

hmm im curious as to how my buschur racing gt35r is gunna perform on my stock motor

 

I am stock motor with ported head and upgraded valvetrain and it is working great for me

Keith

 

Will the Mivec have any diffrence in spool up ?

 

It may have some advantage, but the stock programing is optimized for the stock turbo. Customization of the intake cam phasing would help a lot I would think.

Why don't you do some data logs of your setup and let us know the results? All the speculation in the world is worthless.... sort of the reason this thread was started was because of people claiming they have a GT-35R on a 2.3 stroker motor spooling as fast as a stock turbo does on a 2.0 motor.

I suspect that a stock EVO IX turbo spools up faster than the stock turbo on my old 03 EVO VIII and a GT-35R could potentially spool faster on the EVO IX if the intake cam phasing is optimized for that setup.

Keith

PS: If you tell me you don't have a data logger when you have around the price of a second EVO invested in parts for your IX I will be amazed and dismayed.

 

Will do, i have to ask the guys at pruven performance to get me that information im pretty sure they have that.

 

I'll add another 3rd gear log to this thread today since I'm almost finished with my pump gas tuning.

Couple things I've noticed which I feel is worth mentioning is that ignition timing doesn't have all that much effect on lower end spoolup. What I mean by that is I've tried reducing the timing down low to keep the exhaust gases more dense and try to spool the turbo quicker but it didn't make much difference. All it did was make the car feel slower.

Another thing I noticed is that when you go WOT has a much bigger difference on low end spool up then anything else. I think in order to compare apples to apples here we all need to hit the gas at the same time, like 2000RPM. I have logs on the same stretch of road where I've gone WOT @ 2k and then 3k the difference in spoolup between when you go WOT and the amount of boost you see at 4k is like the difference between 2nd & 3rd gear spoolup. Basically you shouldn't compare a log that starts going WOT @ 2k in 3rd gear with a log that goes WOT @ 3k in 3rd gear because the one that started in 2nd gear will make more boost in a shorter amount of time.

 

FWIW, I didn't see anything in that list that pertained to tuning.

That's because things don't work that way. Cooler, denser exhaust gases don't help anything where power is concerned. On the contrary, it is hot, energetic exhaust gases that do. Retarding the timing only reduces power, and therefore reduces heat (and spool time). However retarding the timing far enough causes some of the air/fuel charge to burn as it exits the exhaust valve, which does spool the turbo quicker. Unfortunately, it also sends EGT through the roof and tends to destroy the exhaust tract given enough time.



The longer the time the engine is placed under severe loading (e.g. WOT run from 2k rpm in 4th), the more heat is generated, and the lower in the rpm range the turbo will spool (generally speaking).

 

The reason I made that comment was because much earlier in this thread someone, trinababe I believe, made the comment that they could get the turbo to spool super early by retarding ignition timing. I tried it out and saw nothing but lack of performance. I'm glad my finding agree with what you said.

Here is my 3rd gear log from today. I'm pretty much done tuning now until I do cams or another mod.



Boost was set around 22-23psi, you can see where it starts slowing down spool @5k.

 

All of the data on my chart so far is for going WOT at 2000 RPM in 3rd... I agree with you 100% about the difference in spool if you wait till later in the RPM band to go WOT.

Can you pull data points every 100 RPM and put them in a text file for me so I can add them to my chart?

Thanks,

Keith

 

2000 0.06
2100 0.68
2200 1.03
2300 1.42
2400 1.6
2500 1.9
2600 2.07
2700 2.29
2800 2.6
2900 2.99
3000 3.43
3100 3.73
3200 4.3
3300 4.91
3400 5.48
3500 6.14
3600 6.97
3700 7.84
3800 8.76
3900 9.28
4000 10.38
4100 11.6
4200 13.04
4300 13.83
4400 15.53
4500 16.45
4600 17.45
4700 19.42
4800 20.21
4900 21.47
5000 21.96

 

Hi all , I'm at bit surprised at what some people are calling a GT35R/GT3582R .

What I call a GT35R consists of a GT25BB centre section with an 84 trim 68mm GT35 UHP turbine plus a 56 trim 82 mm BCCW-18C or GT40 compressor .

Why anyone would want to use any less than the T04S .70AR compressor cover is beyond me , you can forget all about Garrett's comp map with any T04E housing .
I see that some are using .63AR ratio turbine housings which may or may not be Garretts on GT35 type housing . Assumes yes , maybe some should look at turbobygarrett. coms turbine maps for this turbocharger and note the maximum flow potential for the .63 GT35 turbine combination . Not real flash when you consider the lbs of air that its GT40 compressor can move . Most people here in Aus don't like this setup because you will wind up with huge turbine inlet pressure in relation to boost pressure , I believe the .82 is a realistic minimum .

The GT35R is already a hybrid in a way because it uses the TO4S sized backplate/adapter ring and housing . Most GT40 style compressor ends use a larger diametre backplate ie GT4082/GT4088/R importantly with more diffuser area . The GT35R being the largest of the GT25BB centre section turbos would have been limited by this centre section size .

There is another type of "GT35R" which is the one off HKS GT3240 , similar thing only cropped turbine (approx GT32 84T dimensions) and a 54 trim version of the GT40 82mm compressor .

I'd really like to see Garrett offer the GT35R in a variety of compressor trims especially since that family of compressor is available in 50/52/54 and as we know 56 trims . Blind freddy can see that as the compressor trim falls the load on the turbine falls with it so boost threshold or "spool" if you call it that drops as well (all else being equal) .

If you look through the maps of these wheels its easy to see that most if not all of them can churn the air for ~ 530 Hp and upwards . I believe that if Big G saw it in their heart to market a 52 comp trim version its possible to make the same or more power more reliably with the mid or even the large AR turbine housings ie .82 or 1.06 . I don't think the .63 housing would be much chop on any version except maybe a 50 T version . A reasonable comparison is the GT3076R series turbos which tent to be 56 trim compressors though HKS also market a 52 comp trim version . The spool difference is said to be ~ 5-600 rpm in favour of the 52T type , if you can live with its maximum airflow the 56T type is a step backwards in many instances . Time for a GT3582R 52T I think .

The GT3040R , I've never seen any have raging success with this turbo because of the size mismatch between the turbine and compressor . I'll be bold and say its probably something like a 480-500 Hp turbine side with a 700+Hp compressor end so not real good . HKS also market their spec version of this turbo and the main difference compared to the one Garrett sells is compressor trim , 50T for HKS and 56T for Garrett . Sadly its all to easy to fall into the trap of thinking yeah bigger trim Garrett you beaut . The real world experience is that the 60mm GT30 turbine struggles to drive an 82mm compressor and the big trim version means its on its knees for no good reason . The pretty HKS tag stating power and response reads true , no kryptonite magic technology just a compressor a bit more in step with the turbine driving it . From HKS they say their GT3040 is good for 490Hp or 710 CFM , for their 56T GT3037 they say 460Hp or 670 CFM . Depending on turbine housing AR I'll bet the turbine inlet pressure difference is significant .

Cheers all from Aus .

 

Chart updated with data from Alwaysinboost.

Always, what is your setup? You start off spooling like a GT35R on a 2.3 liter and then fall off dramaticly to spooling like a GT35R on a 2.0 liter....

Keith

 

My setup consists of an untouched 100% stock 2.0 down to the stock headbolts. RNR standard 8 gauge manifold, garrett 35r w/.63 turbo & my tuning. I think I know the reason for the early spool up, I never realized it until you posted that graph. I'm going to experiment with something tonight and see what happens.

 

I wonder how much the bbT67 will compare to the 35r??? couple of hundred rpm difference at most I hope...Thats what I am going with.