I am just wondering how much boost you can put into a stock 12a engine?

 

As much as you want.

 

completely stock? i wouldnt go for more than 7 psi

 

how much power would it the 7 psi give me

 

Depends how high you rev the egnine y0.

 

Bah, you can run much more than 7psi. The stock 12a is fine for up to 16psi from time to time(I should know ). For normal, everyday driving though keep it around 12psi(or lower if you want).

 

hope you don't mind rx78788, but i'm gonna semi-hijack your thread...


2 questions...

1, while we are on the topic of psi... what would be the reccomended on a Streetported Engine? / what is it about a stock engine that makes you want to keep the boost down....

2, may pertain to question 1.... Do you really need a self retarding MSD ignition (can't remember the #) or will a DLIDFIS work ok?

 

Turbo dummy here. How do you adjust the boost on a turbo and will any turbo work or do you need a specific type or what?

 

RX78788, what turbo setup you got? what custom work did you have to do? you have probably told all of us before but i can't keep names and setups straight.....please shed some secrets! i want a turbo!

 

oh yea, i've always heard 8psi is safe, don't know to much about turbos but i just recall somone telling me that.

 

but dont you have the jspec 12at? or is that someone else? i dont know but i wouldnt recommend boosting as much as you do; but if you did it, more power to ya

 

i used to run 13psi all day long, untill that dam engine fire.......

 

boost ? did i hear you say boost? how about junkyatd boost!

 

Brian - Turbos are designed to work with different exhaust pulses from different engines and their different port design, number of cylinders, etc.... So no, not ANY turbo will work, although I believe some turbos from more common vehicles work... I'm not to sure though.


Also, Boost is controlled by either a wastegate (a pressure relief valve that allows excess boost pressure to bypass the intake system and return to the exhuast system). Some systems use adjustable wastegates and boost controllers.

 

a waistgate allows exhaust gas to bypass the exducer wheel, thus controlling boost. not what you said

 

off topic:

Keaponlaffen thats got to be the funnyest sig haha.

 

Can the stock 12a not go over 12psi for everday driving because of not being ported or what? What are the horsepower differences in a turbo 13b EFI and a blowthrough 13b (dyno's would be nice).

 

I found the claimed horsepower differences between 12aturbo and an N/A 12a.


-----------------------------------------------------------------------
originally posted by fitzwarryne


Stock 100fwhp USA 110fwhp European

Stock with modified Nikki carb, street performance exhaust with other bolt on/off mods 150-155fwhp

Streetport with full street mods as above 180-185fwhp

Street port with efi and street mods 220-225fwhp

Bridgeport 48 IDA with street mods 215-225fwhp

Bridgepor 51 IDA with race set-up 235-250fwhp

Jport 51 IDA with race set-up 250--275fwhp

Monster port with 51-55 IDA race set-up 260-300fwhp

PP with 51-55 IDA carb full race set up 280-320fwhp

---------------------

Stockport s4/5 turbo blow thru carb with intercooler 160-185fwhp

Streetport turbo blow thru Weber street trim 190-280fwhp depending on turbo size and boist

Maximum turbo set-up for street/drag 350-425fwhp

Maximum turbo set-up for drag strip 600-850fwhp

---------------------------------------

12AT stock 136fwhp

12AT with upgraded turbo, ecu, ports in street trim
185-280 fwhp.

There is no data available for higher levels of mod

--------------------

These figures are good indicators of peak power, There will always be exceptions. In the case of turbo there is a lot of variation and reliable data is limited.

 

I'm using a J-spec 12a turbo intake manifold cause it's the cheapest intake I could get that would not hit the turbo. My engine is a completely stock 12a with 140k miles on it.

A stock 12a's limit is 16psi because after that it'll cause a dowel pin leak pretty quickly, but 16psi is alright from time to time. At 12psi my car probably makes around 250hp, does 0-60 in 5 or 5.5sec and 1/4 in the mid 13's. I havn't actually ran my car on the track, I'm just judging by what my friends g-tech said and by all the cars I've raced.

 

12at is 160 hp from the factory. those numbers are real funky. a stock port s4 with a turbo, only 160-185 hp? you got to be ****** kiddin me! you can get more than that with bolt ons. who ever came up with that stuff, aint right!