What GT turbo to go for?

[campbellju]

Upto 380bhp but no more.

On a T28 and lots of good external engine mods I was making a happy 320 at 1.2 Bar and had done a trial at 1.5 Bar with the help of octane booster and making 350hp though it was running too lean for my liking. With more fuel it might have made 360 but that is accademic now.

Since then I have had the turbo slightly upgraded and a very good engine rebuild (Can't be bothered to go through it all).

In the past, people were getting 380hp from T28's by clipping wheels etc. I don't want to do this so am trying to cut mechanical wastage and bottlenecks rather than just boosting power. At 1.6 Bar I believe 360 is realsistic, 370 is possible and "upto" 380 is the limit. However, at 1.6Bar I will have high temps so the plan is for water injection with a bit of metnanol or nitro methane to push it closer to the 380.

Who says I have to play fair


My aim is a sub 400hp low lag rally slag but I might stuff it and just go for the gt2871r :lol: :lol:

 

[campbellju]

How are you going to get 380bhp from a GT28RS... At 1.6bar you are looking at about 340bhp...Rishi

A few people on standard engines and turbos are getting 340 from 1.4Bar

Car HP and flow maps are not a direct link. The rated HP is often for the middle of the flow map where the turbo is running at maximum efficiency. A good intercooler will solve that. You need to look to the choke point to see what the actual max flow is and then calulate that through. The actual HP of your car is dependant on the Volumetric Efficiency of the engine.

Jim

 

[Rishi]

How are you going to get 380bhp from a GT28RS... At 1.6bar you are looking at about 340bhp...Rishi

A few people on standard engines and turbos are getting 340 from 1.4Bar

Car HP and flow maps are not a direct link. The rated HP is often for the middle of the flow map where the turbo is running at maximum efficiency. A good intercooler will solve that. You need to look to the choke point to see what the actual max flow is and then calulate that through. The actual HP of your car is dependant on the Volumetric Efficiency of the engine.

Jim

I was looking at the peak... 340bhp @ 1.6bar... 1.4bar will give you much the same result... Looking at the map, there is vertually no difference between 1.4 and 1.6bar bhp wise, with regards to the GT28RS...

But if you've modded your turbo then fair play..


Rishi

 

[Keira]

A few people on standard engines and turbos are getting 340 from 1.4Bar

mine made 340bhp allegedly at 1.3 bar on a nothing special hybrid t28.

 

[Sweeny]

Uncle winnet on here made 342bhp on 1.1 bar :shock:

 

[billygtir]

i wouldnt buy one of them tbh V
when i took my bb37 to Turbo Dynamics they laughed at the quality of the machining it was poor and that was what caused alot of the lag issues i did speak to jgy about it etc and they said they were working on improving it etc but i dont think u can beat british machining etc
there was less lag on the 3071 than there was on the 2781 i got from jgy

I took the same turbo to turbo dynamics to have a actuator made they said to me it was a very good turbo and good for two bar all day long :roll:

 

[stugtir]

i made 336bhp@ 1.05 bar on a gt28rs from atpturbo.com at the pts rolling road day 8) that was the .64 one not the .86 i think u will find the most the .86 gt28rs will go is about 360 maybe 370 at a push.


stu

 

[00sid]

ive got a gt2871r .86ar with 4" inlet from atp and im making 396bhp at 1.6bar, but the car was mapped with leaking manifold gaskets so it might make a little more when i remap. im well happy with this tubby it spools up nice and quick and holds all the way to the redline, only thing is i would like to change to external waste gate to hold more boost better.

 

[Fast Guy]

Yep my mistake, GTRS

 

[krikra]

My GT28RS was maxing out the MAF running 1bar.. Isnt 5,1V from the MAF somewhere near 350hp?

Thats why Im changing to Z32 MAF and going blow thru

I think I'll go with the GT3071R-WG in order to make 400hp @ 1bar
Even though it might means a little more lag than the GT2871R :?

 

[Keira]

external waste gate to hold more boost better.

only got to disconnect the actuator hose or remove the whole lot completely and weld it up

i say do it 8)

if you weld it up and yours works ok you can do my 3071 :lol:

 

[ashills]

i wouldnt buy one of them tbh V
when i took my bb37 to Turbo Dynamics they laughed at the quality of the machining it was poor and that was what caused alot of the lag issues i did speak to jgy about it etc and they said they were working on improving it etc but i dont think u can beat british machining etc
there was less lag on the 3071 than there was on the 2781 i got from jgy

I took the same turbo to turbo dynamics to have a actuator made they said to me it was a very good turbo and good for two bar all day long :roll:

when did u buy yours as mine was first batch they had made after that i was told they changed over to using the 2871 from ATP turbo but stiill calling it there own turbo

there actuator brackets are a work of art took 2 hours for them to do mine lol