So it seems that most people are running 21psi ~ 24psi on the GT35R on pump gas... then 28psi ~ 36psi on methanol and built motors. My question is... what's the highest anyone's boosted on a 35R and continued to make power... especially with the cooling effects of methanol... and especially on a larger nozzle like the M15?

For example, I was bombarded by ppl telling me that the stock turbo is ineffecient after 24psi and its just blowing hot air... but managed to make some crazy power outta it close to 30psi on methanol... now I'm wondering of the same concept can be applied on the gt35r and boost 36psi ~ 40psi with the aid of a large dose of methanol...

Just trying to get some feedback from ppl who may have tried this... this is purely for curiosity's sake. This will also help me figure out if I should sell my 3.5bar map sensor and buy a 5bar map sensor or not...

 

This is a good question, but it does seem that we only here about people and/or shops using gt42r's or bigger to go more than 35 psi. I think this is a good question for Buschur or AMS.

 

I made 565whp at 33psi. Stock intake manifold. Old 7.7/1 compression 2.4. I tried higher boost. Didn't knock but didn't make more power. reached some other restriction in the sytem.

 

True CT9, but remember that the stocker was spiking to 30 and dropping to the low 20's by redline. Curt Brown ran 40psi, but the returns are diminishing the power difference from 35 to 40psi is small. You can expect to max out around 650awhp with all of the supporting mods if you need more than that it's N2O or a bigger turbo.

A great example is Chris's old AMS 35R setup at 32-33psi it did 601awhp at 38psi it did 638awhp...6 or 7lbs for 37psi isn't great.

 

And they weren't wrong.

They were referring to rpm where peak power is produced, not peak torque. The engine is moving much less air at the torque peak, so 24 psi at 4500rpm and 24 psi at 7500 rpm are two very different situations where the efficiency of the turbo is concerned.

Where the GT35R is concerned, the cooling effects of methanol are indeed beneficial, but keep in mind that the greater amount of air and fuel the engine is consuming at higher pressures and rpm, the injection volume of methanol remains static, so the percentage of methanol is effectively being reduced as the hp rises. This is something to keep in mind for the brave souls who aim to try it at 35 psi (or more).

 

By the way CT9 everything I referenced was 100% VP116 Race gas. If you're talking running a pump/methanol I wouldn't be pushing more than 25-26psi even though people have done much more...aka IVEY 32psi!!

 

Charles is too girly to push the limits of the turbo.

 

Newer kits add alky per PSI, they are not static kits anymore, atleast not the good ones.

 

You're missing the point.

When the injection rate reaches its max (let's call it 20 psi), any increase in boost pressure and/or power beyond that point increases demand for fuel, but the injection rate of alcohol stays constant beyond that point, which effectively reduces the concentration of alcohol in the fuel mixture.

 

Are you saying that the kits start at say 16PSI and end at 20PSI? I believe that add more then that per PSI. I am pretty sure the Buschur/SMC kit offers a linear progression from 16-28PSI atleast. I believe Al could answer this question better then me but I doubt that this is the case with less and less alky.

 

I have the kit in question, and I understand its function very well. The user sets the pressure point for the onset of flow, and the pressure point for max flow. The kit's logic IC calculates a ramp between those two points.

When you're at 10psi, you probably don't want max flow.
When you're at 15psi, you want some flow, but not necessarily max flow.
When you're at 20psi, you want max flow.
When you're at 25psi, you want max flow.
When you're at 30psi, you want max flow.

Max flow doesn't change. It's as much as the system can deliver, just like a maxxed out fuel injector. The fuel demand *does* change from 20-30psi, but the alcohol flow is already at its max. This means it is progressively becoming a smaller composition of the fuel charge as the pressure/power increases, simply because fuel usage is increasing.

Get it?

 

check my sign.

 

40PSI on the stock turbo!!! WTF

 

40psi on the 35r....

you guys put too much enphasis on boost pressure(mainly jasil), there is much more involved.

to say you should only run 25-26psi when running pump gas and alky is not a complete statement.....too many other variables.

anyone know what he effective octane being combusted is with the stock SMC meth jet maxxed out(when the pump is at full blast) with 100% meth and 93 octane?

 

That depends on the hp level at that point and the corresponding fuel flow. You'd have to create a specific, hypothetical situation and calculate mass percentages from there. You'd need to provide hp, AFR, and injection kit nozzle size (assuming the pump is capable).