GT2871 USERS. SR motor

[Silvia_Drift]

I need some advice if you guys don`t mind. I got my car tuned last year. Here is my setup:

- GT2871R .64 (bolt on T25/8 style housing)
- Internal Wastegate, HKS actuator
- Nismo 555cc Injectors
- Stock intake/exhaust manifolds
- Stock TB
- Power FC D Jetro
- Full 3 inch exhaust
- Huge FMIC
- BC Step 3 272 Cams
- BC Titanium Springs and retainers
- Cometic Head gasket, ARP studs

The car put down 335whp at 18psi down to 16psi before redline. Car ran a 12.4 at 115mph with a 1.99 60 foot. Dynapack dyno.

Because of the cams, the car is very laggy. Pretty much the whole setup is good for low and mid range, except the cams. These cams are designed for high RPM/big turbo. I am thinking that once the cams are getting into their efficiency, the turbo is getting out of efficiency, which contributes to the laggy response.

My question is, if I put the stock cams back in and get a retune, will I end up loosing power? I know the stock cams would match my setup but I would like to stay at around 335whp.

Here is the dynosheet for my current setup

[EsChassisLove]

Try 264 or 256 cams.

[Seraphim38]

(yes, with stock cams you will lose power).

[Pantaloons]

rammy. my buddy brad made 340whp with stock cams at 16psi so...

[jubee]

There were quite a few people that were running a .86 2871r and hitting 450 whp, this was a couple years back. I was also running a 2871r .86 on my sr and was pretty happy with it, only time i got to dyno it was when i first got it, and i was only running 7 psi and was putting down 240 whp. Stock head, stock injectors, stock bottom.

[ke70 sr20det]

any new vids from your side cody

[BiG MiKE86]

Originally Posted by Pantaloons

aem meth kit with actually water/ meth used... not washer fluid like all the cheap kids

and i use it for drifting

Mind giving me the model no. for your kit? Im really interested in going this route

You havent noticed any problems while drifting? Just wondering if the sidewayz action may starve the meth kit of fluid from time to time or with a lower level of fluid

[cotbu]

I bit the bullet, switched to an external wastegate and quality manifold. That alone gave me 22hp and 15tq at the same 17psi boost level. Boost stays rock solid, Wastegate is loud as hell. I do have my peeves, exhaust housing bolts decided to back out, even though I only clocked the compressor housing, test pipe bolts kept backing out as well. loctited those bad-boys. I'm currently retuning with Nistune also, but i need to upgrade my injectors.
I think 400hp goals are so overrated now! Another 2-3psi and an injector upgrade I'm there!

Oh yeah, those hating on external gate setups or just on a budget. I say do it anyway you probably read as much info as I did about the pros vs cons.

Originally Posted by BiG MiKE86

Mind giving me the model no. for your kit? Im really interested in going this route

You havent noticed any problems while drifting? Just wondering if the sidewayz action may starve the meth kit of fluid from time to time or with a lower level of fluid

I'd like to here more about your setup actually, Is it the single nozzle setup in the cold pipe or tuned port type?

[codyace]

Originally Posted by Pantaloons

aem meth kit with actually water/ meth used... not washer fluid like all the cheap kids

and i use it for drifting

I wouldn't be so quick to discredit washer fluid, as I could post up quite a few members who have used it for years without any worry (to include myself). There are pros and cons of any of the options for a meth kit....if basic detonation resistance is the main goal, Washer Fluid works well and is ridiculously cheap (not to mention accessible anywhere).

In regard to power, I've personally dynoed cars back to back switching between 'fuels' and the power difference was pretty negligible IMO on the same tune. I will say this, a teaspoon of Nitro-Meth into the mixture does however make some silly power gains hehe...but it's not something I'd suggest for everyday use. The Cobra did love it though

Originally Posted by Silvia_Drift

My question is, if I put the stock cams back in and get a retune, will I end up loosing power? I know the stock cams would match my setup but I would like to stay at around 335whp.

I'd put money on you probably making the same power lol...BC stuff is jank.

Originally Posted by jubee

There were quite a few people that were running a .86 2871r and hitting 450 whp, this was a couple years back.

True, but they were all 24+ psi and race gas...that's a no brainer to making power. I don't like to focus much on race gas cars as it really isn't showing a well setup car, just how well timing influences power production hehe.

Originally Posted by BiG MiKE86

Mind giving me the model no. for your kit? Im really interested in going this route

You havent noticed any problems while drifting? Just wondering if the sidewayz action may starve the meth kit of fluid from time to time or with a lower level of fluid

I use a Snow Performance basic kit (pump, reservoir) mounted in the trunk, a inline selenoid to prevent siphoning, and then the the nozzle welded into the coldpipe just below where it enters the engine bay. I wanna say I have a red nozzle, but I can't remember (whatever the 350-450 hp nozzle was).

In regard to drifting, you should never ever 'run out' assuming your tank is gravity fed, and the pump is close to it. In my example, the tank is directly above the pump.





don't mind the shitty aluminum welding, I had the wrong gas with a shitty spool gun. I remade it and had a friend tig it,as that really bothered the hell out of me looking janky.

[tabasco122]

I like that meth setup, it looks nice. I may end up putting mine there and moving my battery between the rear strut towers. i really dont like the battery where it is currently.

[EsChassisLove]

Detonation resistance is my only need for water/meth. Fucking knocking.like a Bitch ever since coming down here to this dank ass 91octane that performs like 87oct.

Ima get all this work done, then after a tune if I'm still knocking, wiper fluid

[Kingtal0n]

Originally Posted by tabasco122

Engines are basically air pumps. more air an engine can move (and adequately provide fuel for) the more power it makes. That turbo cannot flow enough air to hit that power goal. the only way possible would be to build the car for a huge shot of nitrous (which is like liquid air).

I try to keep in mind that turbochargers do not flow mass, only volume. so the perspective power output conversions (CFM-MASS) is always using some kind of temperature conversion, [usually] with a built in efficiency loss for the compressor.

now, if you could supercool the air before it got to the compressor, it would flow more mass of air (the air would be "heavier"/denser) and therefore more power would be made, since more air molecules are packed into the same space. A maf would auto-adjust. A MAP would not because boost pressure remains the same- hopefully there is an IAT correction?

so a turbocharger flowing 20lb/min of air might flow 25lb/min at the right inlet temperature. see where I am going? A t-25 might hit 300horsepower if we could bring the inlet temp down to... well very low. but we could right? we could if the maximum velocity of air is not reached(that t-25 out/inlet is not very large). The trouble is cooling, even spraying water/meth is not going to do much to ambient temp air, plus the fact compressor wheels do not like droplets of water hitting them at 80,000 rpm. So that scenario is pointless to consider. spraying it after the compressor adds its heat would increase the density of the air after the compressor so you are still restricted to the basic CFM->MASS conversion supplied by ambient temperature air as it is affected by the compressors efficiency. In other words, it acts more as an ["octane improver"/detonation retardant] than a "power improver". We could do the same thing with an Air/ice-water intercooler, within reason. the added power comes when the air gets denser, and the compressor has more headroom for flow to pick up the slack. if the compressor is maxed out, lowering the temp after the outlet is only going to reduce power ( lowers thermal efficiency ) , because "engines always make the most power with the largest mass of hot-as-possible air". (quoted from crossfire TA!)

[codyace]

Originally Posted by Kingtal0n

Bill Nye Post

I'm glad people like you post...I don't have the ability/patience to type that all out to help others hehe

However I'd love to see the theoretical IAT to allow a T25 to make 300 whp...assuming it even moves the needed air (lets not forget flow and volume are somewhat related)...-30*F temps? Hahah.

Oh well. Nice to see you posting again Good seeing some OG on here.

[Kingtal0n]

Originally Posted by codyace

I'm glad people like you post...I don't have the ability/patience to type that all out to help others hehe

However I'd love to see the theoretical IAT to allow a T25 to make 300 whp...assuming it even moves the needed air (lets not forget flow and volume are somewhat related)...-30*F temps? Hahah.

Oh well. Nice to see you posting again Good seeing some OG on here.

Sup cody! yeah man when I procrastinate my study time I usually hit all the forums, wash my car, clean my room, whatever it takes to avoid studying lol.

Ill always remember the engine with the straight pipe from turbocharger->throttle body. Response was good, compressor was maxed. The guy added an intercooler, thinking cooler air = more power. Well, air temp decreased, response got worse, boost pressure decreased, and the compressor was still maxed so power stayed the same. he went back to a straight pipe XD

[cured13]

Originally Posted by Kingtal0n

Ill always remember the engine with the straight pipe from turbocharger->throttle body. Response was good, compressor was maxed. The guy added an intercooler, thinking cooler air = more power. Well, air temp decreased, response got worse, boost pressure decreased, and the compressor was still maxed so power stayed the same. he went back to a straight pipe XD

interesting,

do you know how long his engine last?

[tabasco122]

Originally Posted by cured13

interesting,

do you know how long his engine last?

its possible to run a turbocharged car without an intercooler, but you either have to increase the octene, or run methanol. also, you wont be able to run very high boost levels afaik.

[2forty]

Originally Posted by Silvia_Drift

I need some advice if you guys don`t mind. I got my car tuned last year. Here is my setup:

- GT2871R .64 (bolt on T25/8 style housing)
- Internal Wastegate, HKS actuator
- Nismo 555cc Injectors
- Stock intake/exhaust manifolds
- Stock TB
- Power FC D Jetro
- Full 3 inch exhaust
- Huge FMIC
- BC Step 3 272 Cams
- BC Titanium Springs and retainers
- Cometic Head gasket, ARP studs

The car put down 335whp at 18psi down to 16psi before redline. Car ran a 12.4 at 115mph with a 1.99 60 foot. Dynapack dyno.

Because of the cams, the car is very laggy. Pretty much the whole setup is good for low and mid range, except the cams. These cams are designed for high RPM/big turbo. I am thinking that once the cams are getting into their efficiency, the turbo is getting out of efficiency, which contributes to the laggy response.

My question is, if I put the stock cams back in and get a retune, will I end up loosing power? I know the stock cams would match my setup but I would like to stay at around 335whp.

Here is the dynosheet for my current setup

You should have been making alot more power. my old motor was only a t28, hks 264 step 1s, enthalpy tune, and was trapping 114mph @ 17lbs. Never had it dyno'd but i figured around 300whp. A 2871r and Power FC should make alot more power...

[zurud]

Any body has regret putting gt2871r instead of top mount t3. I am installing gt2871r right now . Its kind of a bitch to put them on. I think top mount t3 will be alot easier.

[tabasco122]

louisiana guy posted a dyno sheet on another forum im on. its impressive, until you start looking at where the power comes in at, the lag on this thing is unbelievable....

pump


and e85 (wish i had some around me)



here is his mod list

S13 blacktop sr20
Balanced and blue printed
Kings racing bearings
Eagle rods
CP pistons (9:1)
Mazworx stage 2 head (combustion chambers opened up and oil journals opened more)
Supertech valvetran(valves, springs, and retainers)
Enjukuracing rocker arm stoppers
Tomei 270/270 12.5 lift cams
Greddy intake mani (all casting clean out and polished)
03 mustang gt TB 65mm
Peakboost turbo mani and Dp
Prescion 6262 BB .82 A/R
Tial 38mm WG
Apexi gt spec 3 3/4 exhaust (no cat or resonator, very loud)
Greddy R intercooler
Walbro feeding a Bosch 044
All AN -6 lines from tank to rail and back
Aeromotive FPR
JGY fuel rail with a single center feed with 2 returns on the ends
ID 1000s injectors
AEM EMS 1601
Tuned by CTP Mr Seth Francis
E85 at 70psi fuel pressure making 610hp at 6500rpm!!!!!
And 520ft/lb at 6500rpm!!!!

my engine can most likely handle that kind of power, but who wants that? its almost unusable because he doesnt make any power till after 5k

[slider2828]

^^ Damn that is on a dyno dynamics, but the lag is undriveable though! Geez....

[Csomme]

OMG. Tsunami graph rather than turtle back. That's a disgusting looking dyno graph.

[tabasco122]

yeah, codyace's car makes twice the hp at 4k than his. its almost like his turbo hasnt even started to spool at that level...

[codyace]

Originally Posted by zurud

Any body has regret putting gt2871r instead of top mount t3. I am installing gt2871r right now . Its kind of a bitch to put them on. I think top mount t3 will be alot easier.

A bitch to put on? How so?

Take the manifold off, and add stainless steel lines...super easy.

[drag113]

Are you guys seing any leakage between the block and head area of your metal headgaskets? Engine still runs good. It leaks very slowly but over time my block gets sludge and looks horrible.

[tabasco122]

Originally Posted by drag113

Are you guys seing any leakage between the block and head area of your metal headgaskets? Engine still runs good. It leaks very slowly but over time my block gets sludge and looks horrible.

you mean on the outside of the engine? did you retorque the head bolts after 1000 miles? i have only put about 1000 miles since i put my apexi hg on, but i notice no leaking at all. engine is still clean from the machine shop.

[drag113]

Havent retorqued. Never got called in to get them retorqued by my tech

[tabasco122]

i know on the apexi its recommended to retorque the head bolts after 1k

[JL240]

ok gurus i need your opinion on cam choice for my set up wich is
gt2871r .86
hks exuast mani
740cc
power fc d jetro with boost controller
all other supporting stuff with stock internals
the last tune i got it put out 288whp at 15 psi on 91 oct with stock exuast mani
the cam choices that im thinking are :
tomei 260 12.0 procams, jwt s3 or s4 or would i need something smaller? i will be doing springs and ras when i do hg and cams and hopefully upping the boost to 17 psi on the next tune on 94 oct since its tuned for 91oct right now
my general purpose is street and strip on weeknends and my hp goal is mid to high 300s and low 12s on 1/4

[usdm180sx]

Originally Posted by tabasco122

i know on the apexi its recommended to retorque the head bolts after 1k

Really? I never heard of that before.

[tabasco122]

Originally Posted by usdm180sx

Really? I never heard of that before.

Hmmm, apparently some people recommend retorquing them after the first heat cycle and again after 500-1000 miles, but according to some guy who said he contacted apexi, its not necessary. i was told when i bought my car that it needed to be done, i may rethink that now. im paranoid about touching my cams or anything timing related, so i think ill just leave it alone.