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View Full Version : anybody supercharge a n/a 3.8?



blackXR7
08-23-2009, 07:38 PM
Hi, I'm a newbie to ford s/c 3.8, but I've got a couple supercharged 3.8 grand prix's. It's very common to take a n/a buick 3.8 and use the heads/intake/supercharger from a supercharged motor for greater compression. When I spun a rod bearing on my gtp I did this, and I've had no problems. As long as you can scan for kr, there's no problem. I use meth injection for insurance. Can you do this with the fords as well?

sinhumane
08-23-2009, 07:44 PM
i dont see why not. remember that the na 3.8 has a 10:1 compression.. so you might want to keep boost low and the air charge cold and dense. with meth, i could see you making a solid 250 on that engine, and shoulld hold up just fine.

dont listen to the naysayers that think that boost is the ender of engines. poor tuning is the ender.

yes, an sc block is much stronger, but an na wiht a cast crank and rods, with he pistons should hole up fine. the mustang guys do it all the time. :)


truth be told, if you have some skill, pick up an sc shortblock, install it with your na goodies, custom headers and a turbo.

but thats just me ;)

RedSC93
08-23-2009, 07:54 PM
http://www.sccoa.com/forums/showthread.php?t=9577

blackXR7
08-23-2009, 08:34 PM
good info in that thread. however, if anyone melts their pistons, they weren't scanning for kr. But, our grand prix's are OBDII, so it's easy to monitor these things. Maybe with OBDI it's not as simple? I just picked up a 90 XR7/5 spd. real cheap because supposedly it's got a blown head gasket. I'm planning on at least one cracked head. If it's worse, I'm just exploring the options as far as engine replacement goes. Keep the info coming!

Mike8675309
08-23-2009, 09:08 PM
remember that the na 3.8 has a 10:1 compression..

Should be 9:1, not 10:1 for NA compression ratio. I'm not sure what scanning for KR means, but the SC head/intake combo does not appreciate high compression ratios at all. I don't believe the N/A 3.8 block is setup for a knock sensor, or at a minimum there isn't one in there.

The GTP setup is more forgiving than the SC setup is.

blackXR7
08-23-2009, 09:29 PM
I guess I just assumed the fords had knock sensors. Scanning for kr means scanning for knock retard, which the pcm does when the knock sensor senses engine detonation. Basically it pulls timing away when it senses detonation. I know the buick n/a 3.8 comes with cast crank/rods, maybe hyperutectic(sp.?) pistons. So that doesn't necessarily make for a forgiving foundation.

Roadhawg
08-23-2009, 09:42 PM
The forgiving boundary is the GTP setup produces far less boost then the SC setup

decipha
12-13-2009, 03:07 PM
it can and has been done just be safe on the timing and give her plenty of fuel, don't get stupid with her and if you need more power than you need to spend the money and do it correctly

the stock valve train for our supercoupes suck, the cam sucks and the stock valve springs suck, the heaton m90 builds a lot of heat which sucks and our inadequate radiators which sucks retain a lot of heat parked right next to the sucky inter cooler which doesn't help anything at all. Our cast blocks and aluminum heads have a huge problem with electrolysis so be sure you ground each head to the chassis and change that coolant once a year

the stock exhaust sucks and trying to have it flow freely just makes for an aggravating rasp thats annoying as all hell

good luck with your engine/swap/idea/thought hope it works out for you, im not bashing the supercoupes i own 5 and love them all but they are faced with unique challenges that are rather well.. challenging.

frdlvr30
12-13-2009, 03:21 PM
it can and has been done just be safe on the timing and give her plenty of fuel, don't get stupid with her and if you need more power than you need to spend the money and do it correctly

the stock valve train for our supercoupes suck, the cam sucks and the stock valve springs suck, the heaton m90 builds a lot of heat which sucks and our inadequate radiators which sucks retain a lot of heat parked right next to the sucky inter cooler which doesn't help anything at all. Our cast blocks and aluminum heads have a huge problem with electrolysis so be sure you ground each head to the chassis and change that coolant once a year

the stock exhaust sucks and trying to have it flow freely just makes for an aggravating rasp thats annoying as all hell

good luck with your engine/swap/idea/thought hope it works out for you, im not bashing the supercoupes i own 5 and love them all but they are faced with unique challenges that are rather well.. challenging.
If I owned five SC's Id be cursing too....

scxr7
12-13-2009, 05:15 PM
it can be done at stock boost levels. 12-13 psi is safe on a stock n/a bottom end. its really all about the tune. if the tune isn't dead on, you'll bend a rod or throw one through the block. the rods are the weakest part on a n/a motor.

txsc
12-13-2009, 09:37 PM
Asking the obvious...Why wouldn't you just use an SC engine to begin with? It's not like they're big bucks. A salvage yard won't charge one penny more for an SC engine than an N/A engine. Also, there are plenty of members here parting out cars. There's probably one near you. SC engines are readily available. Why hassle with an N/A engine?

bowez
12-13-2009, 10:27 PM
Asking the obvious...Why wouldn't you just use an SC engine to begin with? It's not like they're big bucks. A salvage yard won't charge one penny more for an SC engine than an N/A engine. Also, there are plenty of members here parting out cars. There's probably one near you. SC engines are readily available. Why hassle with an N/A engine?

When I was looking for a replacement there were only 2 I could get a hold of for less than $2k, one in Memphis and one in Austell GA.

Motohead
12-15-2009, 02:03 PM
When I was looking for a replacement there were only 2 I could get a hold of for less than $2k, one in Memphis and one in Austell GA.

look for one here http://www.sccoa.com/forums/showthread.php?t=111325
Herees a free one (if you go and get it) http://www.sccoa.com/forums/showthread.php?t=111306