boosted hybrid

The plans for the Evans Tuning power street car for next season has changed mainly due to the new NHRA track ruling of cars in excess of 135mph need to upgrade to a 10 pt cage, 9 sec license, neck brace, etc, etc. We were trapping 140-143mph regularly with the car at 650whp, and not even putting that power to the wheels until 4th gear. In the interest of keeping the car a true street car (running the power street class in NOPI), we are not going to add the safety equipment to the car for trapping more than 135mph. Instead we are just going to limit the power being made. I opted to change out the Gt35r on the car with a Gt30r we had at the shop. Nothing else was changed on the car except the turbo, so the comparision is what you would see changing from the 30r to the 35r, or vice versa.






Modified by boosted hybrid at 12:13 PM 12/7/2005

null.

very nice comparison!

integranator

iTrader: (2)

Nice, and honestly, the powerband isn't THAT much better than the gt35r.

tony1

Intersting test. I'm actually surprised that the 30r was able to maintain 32psi at that rpm. Did the boost start to fall at the end?

DontBlink

nice test, so theres hope for higher numbers for my 30R yet.

im still running the .63 a/r and got 517hp@23psi from it (maxed out my boost controller due to a small wategate spring)

i also run power street and switching from low boost(471@17-18psi) to high boost(517@23psi)at the 3rd gear shift i was still trapping 132mph on 225/50/15 drag radials. i was going to go to a larger exhaust houseing but i think this might net me a 135+ mph and i dont wanna go through all the safety changes since i just had a bar put in my car at the end of last year.

good luck see ya in power street

boosted hybrid

Pm'd you, Tony.


Modified by boosted hybrid at 10:35 PM 12/5/2005

full Circling

looks like the gt30r has a much better powerband than the 35r until 6k, making it better for the street. informative thread. props.


Modified by ^^whatnoobsearchthenGTFO at 9:52 PM 12/5/2005

tony1

So you think the boost falling was a result of backpressure, and not a result of the compressor running out of airflow?

11psiTurboSI

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by null. &raquo;</TD></TR><TR><TD CLASS="quote">very nice comparison!</TD></TR></TABLE>

a1320addict

iTrader: (1)

awesome stuff jeff...what octane gas?

boosted hybrid

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">So you think the boost falling was a result of backpressure, and not a result of the compressor running out of airflow?</TD></TR></TABLE>

Pm'd you again.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by yehiknowrite &raquo;</TD></TR><TR><TD CLASS="quote">awesome stuff jeff...what octane gas?</TD></TR></TABLE>

Sunoco 110 octane.


Modified by boosted hybrid at 10:36 PM 12/5/2005

tony1

Yeah, i could definitely see the hp difference with the backpressure/turbine change, but I don't see why that would make boost fall? Am I missing something?

downeyballz

the dyno plot shows about a 500rpm spool diffrence, but how does it feel on the street? is it noticable? was the car re-tuned with the gt30r?

Riake

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, i could definitely see the hp difference with the backpressure/turbine change, but I don't see why that would make boost fall? Am I missing something?</TD></TR></TABLE>

Well would it make since that the 1.06 would keep the boost for a longer duration until the compressor flow was maxed out? The less backpressure would enable the compressor to maximize itself for a longer period of time right? Im no pro, but I would think that the compressor would run to 32psi and drop off at the higher rev regardless. However wouldnt the 1.06 hold the 32psi longer than the .82?

boosted hybrid

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by downeyballz &raquo;</TD></TR><TR><TD CLASS="quote">the dyno plot shows about a 500rpm spool diffrence, but how does it feel on the street? is it noticable? was the car re-tuned with the gt30r?</TD></TR></TABLE>

It's about 800-1000rpm spool difference in the mid-range. The transient response of the turbo is a night and day difference than the 35R. The car is much more driveable on the street. The car was retuned with the 30R.

JDogg

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, i could definitely see the hp difference with the backpressure/turbine change, but I don't see why that would make boost fall? Am I missing something?</TD></TR></TABLE>

im w/tony on this one, changing out the turbine will make more power, but i dont see it changing the boost.

i was pretty suprised to see the difference in spool.. the 30r isnt much faster than the 35r. As for garretts ratings... i have done 280 on a gt28rs and well over 600 on the 35r... so, who knows

thermal

Awesome info. This is a plus for those who are still deciding on what turbo to pick. Good stuff as usual from B-H!

cuin9sec

nice ...

timg

I'd love to see the same chart with a 3071R, 2871R, and GT40R added... Makes me very glad that I bought a GT30R rather than a GT35R though.

Tim

NLR

how are you keeping the gate shut? Sounds like backpressure blowing the gate open

B20T CRX

Nice power, but why are you staying with the T3 back housings. the back pressure has got to be high.

Arturbo

back pressure sucks..

Chris22215

Nice powerband How do you think that it'll affect your times?

Dublocivic

Jeff is that gt35r with the .82 a t3 or t4?

downeyballz

why bother changing turbos and losing power, when you could just change tire size of gearing.