Gt30 rb20 build - 1 Year Project + Paint Job Pictures

[Snow]

Do you have a link to that 10 second cars build thread? (assuming he has one...)

[Skym]

Depends on the application.

Short exhaust runners like found on stock RB20 exhaust manifold make turbo respond quicker because there's less distance for exhuast gas to travel to reach and spin exhaust wheel on turbo and when mixed with small turbo, small intercooler, has alot of bottomend pickup, quick transient response when stepping on the throttle.

Longer exhaust runners are for more mid to high hp gain + 1psi less with stock turbo or less psi when fitted with bigger turbo, as boost drops at higher rpm's to near 0 and suit's bigger turbo with similar mid to high powerband.

Longer runners for racetrack, dragracing use, shorter runners for road use. But in saying that, a dude on this forum achieved 10.42sec 1/4 mile with stock RB20DET exhaust manifold and bigger T3/T4 turbo. The intake plenum seemed to be more restrictive than exhaust manifold. Also RB26 has short exhaust runners.

Some have produced up to nearly 500hp with stock exhaust manifold on RB25DET.

[Muss]

you still have that thing

Yup, I do. Offer still stands.

[supguyex]

oh polak... you and your silly ballerness...
but i must agree with having a topmount, it's only cool if you can SEEEEEEE the turbo ahhahaha
thats why paul walker puts his nos bottles on the passenger seat

[PL_GTR]

Topmounts flow a lot better because the runners are all the same to the turbo, all the same length vs like a stock manifold. stock can handle 400hp np, but i want the better response and it just looks baller

[Fairladyz]

Any benefits topmount vs sidemount? My GT32 is sidemount and make a good ammount of power.

[Skym]

RB25DET + 3600rpm sounds about right for 1bar boost with GT3076R on stock exhaust manifold and without V band exhaust housing.

RB20DET probably will be more like over 4000rpm with GT3076R turbo and without V band exhaust housing.

This RB20DET with GT3076R turbo (I gather without V band exhaust housing), top mount exhaust manifold is a good example of how a GT3076R turbo performs on RB20DET. Can see what rpm the big power surge happens at on dyno graph and when engine gets more air from turbo (O+ on boost gauge), fuel to match, etc -

http://www.youtube.com/watch?v=X_mibuiFSuk

[jessem]

Personally, I think you would be happier with the GT3076R with the V-band Tial Exhaust housing. 2.0's are getting full boost (I mean real boost 25-30psi) by 3600 RPM

You could get the stainless v-band inlet manifold built, and a GT30R turbo for the same money as the HKS turbo.

3600rpm?
thats like 2 or 300 later then my rb25 turbo

[GTRs13]

Personally, I think you would be happier with the GT3076R with the V-band Tial Exhaust housing. 2.0's are getting full boost (I mean real boost 25-30psi) by 3600 RPM

You could get the stainless v-band inlet manifold built, and a GT30R turbo for the same money as the HKS turbo.

[DreadedFist]

Kind of off topic question: With those 17 x 8 +38 wheels on the back, do you reckon you could fit 255 width tires back there?

[Skym]

Link says GT2871R turbo.

Info I could find on GT2871R turbo says that 0.86 exhaust housing supposedly helps turbo reach full boost at around 4300rpm on SR20DET. But SR20DET supposedly gets turbo to full boost earlier.

0.64 exhaust housing (like used on GTRS for SR20DET, GT2540 for RB20DET, RB25DET, etc) sounds about right for quicker spool -

http://www.hks-power.co.jp/products/turbo/hanyo/turbinesho.html

Don't need to go external wastegate until around 400hp.

Synapse do sell a longer 1.25" hose for their BOV -

http://synapseengineering.pinnaclecart.com/products/1_25_Silicone_Coupler_12_Long-548-5.html

[PL_GTR]

yeah so, um im going to be running the same snail now... k thanks

glad i could help rabbit, this is probably the smartest root, you can reach whatever power goals you got with more boost and its spools way quicker then a gt30. cheers

[frankiman]

thanks man, i like your build too gl, hopefully the gtr doesn't drain all your funds

no problem with that, i just got a 15k engineering student line of credit approved today, muahhahaha

boxes of parts will be pilling up this winter

[M13]

Good choice for turbo.

[RABBIT]

2.5 inch outlet to the intercooler
4 inch to the compressor housing

yeah so, um im going to be running the same snail now... k thanks