Planning on using the GT2871r to achieve 280whp read good things about it on here.
Was thinking of using a 0.86 for whatever turbo i get as the last thing I want is overheating at the track.......Something i hadnt thought of before was using a big turbo at low boost would i be better of with a 0.64 then if iam not using the turbo to its full potential then it shouldnt be creating too much heat????
I dont want to be raped on the straights or coming out of a hairpin bend which leads to a long uphill straight!

 

Wirelessly posted

Go 0.86.

It will give you the top end you are looking for.

 

Whats done motor wise? 280WHP is do able with 15psi and high on a mostly stock motor. I honestly think the .63A/R will do best you might have a bit higher EGT's but if you are road course racing the car then you want to have that out of the turn grunt.

 

Engine wise is standard just now. Leakdown at 5% on all cylinders. Have 99 head waiting to go on. And fitting forged rods rods before putting engine back in the car.

 

.64
I am making 398 with not the most efficient set up with a 2871 .64

 

Can you post a dyno chart? I want to see how it compares to my .86 ABSURDflow setup.

 

Well yea your hair dryer is at 27psi lol

 

No, LOL.


I feel like I want/neeeed a better IM and your exhaust manifold.....

Let me grab it man.. I just have to find it..

 

Red is the tune with out the water and meth

The orange is my old tune. I believe witht he techIII

The majenta(sp?) and blue are with meth injection.

I am down to hear some ideas on what to do here. My set up as is-is maxed out. I know it can be more efficient.

I believe the the Intake manifold and the exh manifold may be holding me back.

The key here is, I cant have my ftlbs come on any later than it is now. Its already bad. I know you folks here dont do what I do on the track, but response down low is really important. Especially when in tandem.

I am thinking the new BEGI IM and an absurdflow type manifold.

i was even thinking of going with a bigger turbo and using a shot of nitrous to get it going early..

Actually, I should move this thread.

SOrry for the off topic.

 

Yes. Don't do the BEGI IM though. Make a Honzda manifold.

Do E85.

Get 01+ head w/VVT going.

A better flowing exhaust manifold will do wonders for the low end spool.

 

For those not well-versed, my setup:
8.6:1 1862cc shortblock w/ MBSP and VVT
AEM EMS, ID1000s, E85
ABSURDflow manifold/DP
Genuine Garrett 2871R (TiAL .86 A/R exhaust housing)
Blox B18 Honda intake manifold + OEM B18 TB

So even though I have the larger .86 housing, the AF manifold/DP and VVT lets me spool FASTER, to the tune of 25ft.lbs more at 3500rpm and 10ft.lbs more at 4000rpm. 10psi more boost obviously means you crush me past 4200rpm, though.

 

You must be bored, you just made a chart in excel. Lol.

 

I believe that when BEGi did a .64 turbine on Robert's car is spooled later than with his .86.

 

For a street car use the smallest turbo that will hit your power targets. In the choices you gave that would be the 0.64.

If you really are OK with 280 whp, with an optimized setup a GT2860RS with 0.64 will do it. A GT2560 with a good setup will do 265 whp.

 

I have seen in person on a dynojet a GT2560 hit 300hp at the wheels at the North East Dyno Days in the past. It was one of the Jersey Crew guys.

 

Ditto that on another car, IIRC it was like 290-295whp at 19-20psi.

 

Dem's probably dynojet hp. Dynojet horses are smaller than Dynapack horsies.

The 265 number I gave was for a Dynapack. Probably ~300 dynojet hp.


In any case, a turbo much bigger than you need for a given hp target, is a slower street car, due to a weaker low end and slower spool.

 

Very nice. Now see, I am very much into(jeleous) that 25ftlbs more you have at 3500. That is a big difference for me.
I am
9:1
1800cc
99 head
+1mm valves on both sides
head is cleaned up. All casting marked ect have been smoothed. Minimal bowl work.
AEM EMS V2
880 injectors
110 leaded fuel
Stock intake manifold gutted
Stock TB smoothed out
BEGI cast exh manifold
Genuine Garrett 2871r with garrett .64 exh
3" DP and exhaust all mandrel
I need to make some changes and that .86 doesnt sound to bad right now.
I have to research that VVT head..

Thanks for the post Sav

 

Iam thinking bigger turbo such as the GT2871r will flow more low down than the GT2560 or the GT2860rs iam sure I learned that on here?

 

No because it will make a lot less boost in certain areas of the low RPM range.

If your statement were true then we'd be driving with turbos bigger than the engine.