Hello everyone, it's been almost 3 years since I've logged into this site. I see a lot has changed.

So here's the situation; I blew my '87 NA engine a few years ago, took it apart, bought some parts, and never put it back together. Today I found an '88 13B in the junkyard, that was making compression(poor man's compression test), so I bought it. I didn't realize at the time that it was a 4 port intake, meaning it's a turbo block(the car was well stripped, the engine was one of the only things left). I really don't feel like taking it apart to put my other rotors in it, because I know I won't put it back together. I know some people have done turbo-NA conversions in the past, and I was wondering if anyone knows; About how much power would I be losing compared to a stock NA, with the lower compression rotors?
Also, somebody took the front counter weight, and I'm pretty sure the counter weights are different for the turbo and NA rotors. Can anyone confirm this for me?


RIP Icemark. I can't believe you're gone!

 

youd be losing lots of power.
you can think of it almost like the 13b in the fb.

 

^

You do know that the difference between the GSL-SE 13B engine has less than ten horsepower fewer than the S4 N/A...

Have you ever driven a 13B powered FB?

 

So is it fair to say I'm only looking at a loss of about 10hp vs a stock NA of the same year?
I know that's significant, but I can live with that to get my baby back on the road...plus I can make up for some of that by taking drag off the engine.

 

I dont know if it will affect it, but your intake still have the 6 intake ports. Not sure if you can just plug it in and go, someone else with a little know how will have to chime in.

 

It's not plug and play. I need to do a little bit of porting, but it'll work. I'm more concerned with trying to figure out how much power I'm going to lose with these rotors...If it's not worth it then I'll have to swap the rotors.

 

You'll be fine.

 

10 hp might not seem alot but consider also the weight...
What I was saying was that the engine will be almost the same as the gsl-se.

 

GSL-SE Compression: 9.4:1
S4 Turbo Compression: 9.0:1

GSL-SE Intake: 6 Port
S4 Turbo Intake: 4 Port

In addition to the richer fuel map.

I'd think it'd be even worse than the GSL-SE, even if he leaned out the fuel mixture somehow.

 

So basically we're not really sure?
Lol. Well I suppose there's only one way to find out. Thanks for the help guys.

 

it depends. keep the turbo intake manifolds and just put the afm on the other side.


youll get a lil less hp, but that is what an safc is for.

kahren made some nice hp (170+) in one in NA trim. stock ported i believe as well.

 

While you at it, why not start looking for turbo motor parts

 

well i was going to stay out of this, as i want him to have an outside opinion that using my N/a Block would be a better choice, then the turbo one.

Simply the turbo engine is going to suck, nobody knows how much hp it's going to make... and don't give him high hopes, kahren's 170 motor had a alot of cash put into it.

i am willing to drive 1650 miles 13bgxl, and you'd have all 146hp yours supposed too. i could even lend a had getting it back in.

 

I'm sure you could find someone that would trade you straight up for an s4 n/a.

 

Yeah, like me.

I've got extra turbo bits... Top mount, manifolds, a couple choice turbos. (Couple stockers, Turbonetics T70) and various aluminum pipes... Basically everything but the important part.

 

i am pretty sure i pmed him first, but i am pretty sure i have some rotors for my other turbo motor i am building, if i get these rotors i won't need his turbo motor, as much ne ways, still would be nice to have standing by...a blow alot of motors.