I5 GT Turbos 2871 / 3071 / 3076 / 3082 / 3582

[Rusty]

The definitive thread for all things Garret GT, experiences, problems, results etc. etc. These new turbos are getting better and better results as tuners learn how best ot apply them to the I5.

Below is some banter from an unrelated thread...

Referring to my 400bhp target build using either 2871 or 3071:-

2871r / 3071r Same difference, both produce over 400bhp and that's what I'm building the car for. In the process the k24 power keeps going up and up

[MikeLarwood]

2871R will struggle to flow the gases required to produce a convincing 400bhp, whereas the 3071R will produce nearing 500bhp.

I'm not sure whether I'm doing 3071R or 3076R, as I want mahoosive torque and a convincing power number, not a 'just scraped 400bhp' number!

[Rusty]

Such is the beauty of choice...

[Jamo]

2871R will struggle to flow the gases required to produce a convincing 400bhp, whereas the 3071R will produce nearing 500bhp.

I'm not sure whether I'm doing 3071R or 3076R, as I want mahoosive torque and a convincing power number, not a 'just scraped 400bhp' number!

Both will make 400 bhp easy, 2871 has made 450 bhp on an S2

Since the exhaust wheels are the same the flow characteristics are very similar.

The real world difference between the two is 3071 makes more torque where as 2871 sacrifices torque for spool up.

Bhp is easy to produce even an small 1.4 R5 can make big BHP figures, it's the torque that really kills it which is why the RS2 turbo is so good in the real world.

[Fat Audi 80]

BHP is how much money you have, TORQUE is how quick you can spend it! That is all you need to know.

[Jamo]

Yeah that'll be the end just clarifying an obvious misconception about the 2 turbo's

[Rusty]

Might be worth starting a dedicated GT Turbo thread to amass all the info in various threads.

[Rusty]

Phook me! I'm a genius! I created that without moving my hands!!!

[Jamo]

BHP is how much money you have, TORQUE is how quick you can spend it! That is all you need to know.

I was taught it slightly different by a mechanic.

Imagine a boxer

bhp = how many punches he can throw
torque = how hard he hits.

therefore a small engine can still throw as many punches as a large one but because their hits aren't as hard it don't hurt.

[Rusty]

Either way, for my use I think 400bhp & 400ftlbs will be a good target, there are a few other 'enough power' projects on here. The thinking is that less work has to be done to get the car finished and reliable and thus the budget is smaller. I'm still not righting off the RS2 unit TBH, if an RS2 setup came up at the right price then I might be tempted to do the right thing, whole setup is less than a GT turbo :mischeif:

[Jamo]

Either way, for my use I think 400bhp & 400ftlbs will be a good target, there are a few other 'enough power' projects on here. The thinking is that less work has to be done to get the car finished and reliable and thus the budget is smaller. I'm still not righting off the RS2 unit TBH, if an RS2 setup came up at the right price then I might be tempted to do the right thing, whole setup is less than a GT turbo :mischeif:

400bhp & 400 ft/lbs? multiply that by a factor of 1.25 and now your talking

[Rusty]

400bhp & 400 ft/lbs? multiply that by a factor of 1.25 and now your talking

I've barely got the budget for a 0.75 multiplication factor at the mo

Stroker will be a very different story anyway, torque and spool won't be an issue with another ~ 400cc.

[HPmuirt]

400bhp & 400 ft/lbs? multiply that by a factor of 1.25 and now your talking

500 ft/lbs will make 5 bananas out of Orificer Casey's rods

Cheers n

Si

[GazzaG60]

hp is only a calculation based on torque. hp doesn't actually exist.

to make high hp you need torque up the rev range. not that easy to do....and its all at a sacrifice to low end.

hp=torque x rpm/5252

[Rusty]

500 ft/lbs will make 5 bananas out of Orificer Casey's rods

Cheers n

Si

Useful if you're peckish