Hello
which one is the best and fastest spool up Turbo for a 2.5L 951?

I think the t04B 46 trim?
any other sugestions? I just want teh fastete sool up Turbo for the 951.

Konstantin

 

Roughly what would you consider fast spoolup in terms of X psi at X rpms?

 

start build boost at 1500 RPM and has full boost (1 bar or 14.5 PSI) at 2000 RPM
This is fast for me.

Konstantin

 

the fastest way to spool up the turbo would be the callaway 944 turbo way, where the turbo resides on the opposite side of the motor and feeds direct gas off the headers and then plumbs inot the intercooler pipes, the fastest turbo is the one that is sized correctly for your hp needs but in the callaway setup, didnt milledge do this setup too? my k29 #8 would peel out in 1st 2nd and 3rd gear and i had LSD so i dont think it matters much to sizing, if i could get almost instant boost by dropping the clutch at 5500 rpm's with a k29 then so should most of us, it really a factor of driving, some can and cant or wont for fear or driveline damage, i had no problems just some lag till 40 mph or so

 

I need a bolt on turbo that spool up FASTER than a k26/6

no place or time for other mods.
I have already MAF dual Port wastegate ported head etc etc

Konstantin

 

VATN turbo's

15 psi by 2500 rpm or sooner

 

where can i find one for the 951?
are they bolt on for our car?

Konstantin

 

Larger or smaller compressors do not have a huge effect on turbo lag or boost threshold. the compressor wheel is the lightest rotating part of the turbo; hence it's contribution to the total inertia of the rotating assemly is fairly low. boost threshold is mostly a function of the turbo's speed which is controlled by the turbine.

Corky Bell.

 

ok maybe corky Bell believe this but i tried both and yes the biggest part on teh Turbo lag is the turbine wheels but the compressor wheel ALSO afects the Turbo lag
spool up: a k26/6 is faster than a k27/6!

a k27/6 is as fast (if not faster) than a k26/8

 

I had a K27/6 that was rebuilt by Majestic Turbo, and they cut the impeller at an angle for quicker spool up. Reno

 

Konstantin

The fastest I know of it the GT25 Dual BB turbo by Garrett. Its the same turbo that Technodyne uses in his 951 turbo upgrade. Its great but not a bolt on by far sorry. My friend has it in his 951 racer. It has so little friction it spins for about 8-9 seconds after the engine is turned off! I was going to put in my setup but at 8k the bang for the buck was not worth it to me. I did a k27/6 for $750.00

 

just a few thoughts..

The turbo spool up has also a lot to do with differtial pressure across the compressor and the exhaust impeller. If you drop the pressure drops from the air inlet to the cylinder, you will have quicker spool up. I just installed the Lindsay Maf and at coasting, the pressure in the inlet track is close to atmospheric since you dont have the flapper door air flow meter creating pressure drop. (spools to boost about 500 rpm before the stock system) therefore the time it takes the turbo fill up the inlet track is smaller since the compressor has less negative suction pressure. The stock fuling system is by design, a lag inducing system since many steps have to happen from the time you depress the accelerator and boost is produced.

There is a large pressure drop in the intercooler from what Ive read, it would be also a good place to look for enhanced air flow to reduce pressure drop.

JPR

 

Just to second JPR's comments, the PO of my car called Dave Lindsey and asked what can be done to reduce lag and he will buy it.... Dave set the PO up with Boost enhancer and Stage 1 intercooler upgrade... that's it....

 

doesnt SFR have a stage 1 BB turbo going ambient at 2500 rpm?that is by far the fastest spooling turbo ive seen(advertised anyway).its kinda price at $1400 but its a true bolt on.IIRC,turbotim said with the right setup the turbo can hit fullboost sooner. www.speedforceracing.com