my rebuild project is nearing completion

spec as follows :

series 5 13b turbo motor (ex the turbo of course)
carbon 2 piece seals
street port
48 IDA
RB header
rats nest/air pump/all smog removed
std flywheel
competition clutch
series 5 turbo 'box

 

130-140 to the wheels.

 

Healthy street ported 4 port B with a weber?

I'd day a solid 175rwhp.

Perhaps more if you put NA rotors in there.

 

yep, something like that

 

I'm going to be concervative and say 160hp at the rear wheels because of those low compression turbo rotors. Depending on how agressive the streetport is, its possible that engine is capable of up to 190rwhp if you put a weber 51IDA from RB on it.

I fail to see why you have the carbon apex seals in that engine. There going to hurt the longetivity of the engine before they help out in anything. Carbon apex seals shouldn't be used unless you plan on reving the engine to 9K+ rpm, and you don't have the supporting mods for that from what you have written. It kinda looks like a mix and match of parts. No turbo on a turbo engine, carbon apex seals where they don't need to be used, that kinda thing.

 

A lot depends on who ported it and how, a mild SP is going to add 20/30 hp a radical one can add 50/60 hp. Also is the carb jetted properly, was it tuned on a dyno, what exhaust is on the RB header, so many variables I'd hate to guess.

Also agree with 85rotarypower.....low compression rotors hurt your peak hp a lot.

 

He might have NA rotors fellas. he needs to specify.

I'd think a 48 weber would fuel a street port B no problemo.

 

S5 Turbo rotors have quite a high comp ratio anyway plus they are light. This setup should work well if it's sorted out properly.

 

He is right about the carbon apexes. 3mm composites are best for turbo applications. Esp over 12 PSI and under 7,700 Rpm.

 

Ceramic is best for turbo applications whith higher boost levels.

 

You aren't reading the thread properly. This engine DOES NOT have a turbo on it. Its a S5 turbo engine, just without the turbo. I didn't say what I did about the carbon apex seals because they are **** on a turbo. I said it because there is absolutely NO point in using them on anything but a high rev bridgeport or p-port engine. Chances are the engine won't last too long either as the carbon apex seals wear out much faster than regular seals, or so I hear.

FYI, S5 turbo rotors are 9:1 compression while S5 NA rotors are 9.7:1. 12A, 1st gen 13B and S4 NA rotors are 9.4:1, while turbo S4 rotors are 8.5:1. The only oddball NA rotors are the 74-78 13B at a low 9.2:1.

 

hello chaps

yes it is a bit of a mish mash. let me take you through what happened then you will see why I am where I am.

I researched doing the turbo upgrade and about 3/4 way thru my research the opportunity came up to buy a complete s5 motor and gearbox. In my haste I bought it. By the time I completed my research I realised it was going to be to costly to install in my first gen. Its not the gsl-se which I now realise is the only way to go if you want to do the tii swop. So then I had to make a choice.
(1) rebuild my 12A
(2) rebuild the s5 13b

I decided the s5 13b was a better base to start with so went with that one instead. re the carbon seals based on research my mechanic did here these were the ones he recommended.

in hindsight i should never have bought that engine/gearbox combo and just have rebuilt/ported the 12A. would have saved some bucks in the process.

now i'm left with lots of turbo parts and a used 12A......

thinking what I'm thinking ???

 

I see. You shouldn't have trusted your mechanic to do the research. Those carbon apex seals are useless in your application and most likely will wear out faster than regular apex seals. They also don't seal as well in the low rpm's, so you won't get the same kinda power in the low rpm's, leading to harder takeoffs and sliping the clutch more, which wears it out faster.

Its not really a whole lot harder to put a TII into a non-SE car. The biggest things are the fuel pump and the fact that the fuel tank doesn't have a slosh box. Thats easily fixed with the use of a -SE pump and tank. Other than that, its just a few wires that need to be spliced into the FB wiring harness and your ready to go. As with the SE, you will have to be carefull about the rear end and a custom driveshaft has to be made to mate the TII tranny to the rear end.

 

just to confirm, am running the low comp 9.0 turbo rotors. carb is jetted to 190 main, 160 air and 38 choke. gave a very respectable 168rwhp

 

Congratulations on your horsepower output. That is quite a bit.

 

Thats a nice power number there. Congrats for sure.