View Full Version : Stock SC Compression/engine question

01-25-2005, 02:40 PM
I have a '93 SC 5 speed and am planning on doing a re-build soon, but not a full engine re-build. I am going to do true dual Exhaust w/ headers but i've heard that i'll never get a nice rumble from the V6. I've asked around why that might be and i got an interesting response from a guy whose friend used to work for Ford. He told me that the problem basically was the blower. he said that when they put in a stock blower, they lower the compression in the cylinders so the cars doesn't blow itsself apart. Does anyone know if this is true or not and if it's possible to raise the compression to get a more power/a nicer sound?

one more thing...i'm going to be pulling the engine soon and was wondering if anyone knew where to get a detailed description of this process to make it a little easier...Like what to take off first, second, third, and so on...so i don't run into problems trying to get certain things off if something else needs to be taken off first. Thanks for the help.

01-25-2005, 04:50 PM
this is true with any blown/turbo car, you dont want to the compression ratio to be to high or you will blow things up. the stock c/r is 8.2:1 on our beloved sc's. you wont get a great v8 rumble to it because its not a v8, and the blower is what you will mostly hear. i recommend the scp exhaust or that setup, with a res and two mufflers, and big enough pipes that will allow it to breath, id stay around 2.5''. you will get a cool sound out of it, hearing the blower whine is a pretty cool sound, once you free the intake up and add the exhaust.

as for pulling the engine, you want to take off all ur intake parts first, like you intake tube, blower and i/c pipes along with ur in , rear inlet plenum, and then disconnect the manifolds and take those out, then after that all the engine to transmission bolts should be easy to get to. take ur brackets off, and if you want when disconnecting all the plugs and whatnot, makr which one goes where, or you can do it my way and just take whatever you see off, and hope for the best, but in all honesty this engine isnt that hard to work on once you've played round with it a few times. basically work your way from top to bottom. um cant think of much else right now, guess there is always more to it than you think. but if ya got anymore questions let me know. glad to help ya out

01-26-2005, 12:59 PM
yeah, i was afraid of not getting a nice rumble...now that i know that's not an option, what would you recommend for the quietest exhaust possible for the SC? i was thinking of doin Kooks ceramic headers to 2 - 2.5" stainless steel pipes all the way back. from what i've read on this site, there should be enough room for that on a '93 gas tank. I was thinkin of maybe some High-flow magnaflow Cats and some Borla XS mufflers, but i'm not sure how it'll sound. do you have any suggestions for something quiet? And as for freeing the intake up like you suggested, i was planning on running maybe a 3" aluminum cold air intake into the stock manifold and maybe trying to route a type of forced air down "through" the bottom of the front bumper.

Thanks for the advice on the engine and taking off the intake, but i was also wondering the order in which i should take off the accessories so the job goes as smoothly as possible

01-26-2005, 01:14 PM
Let me be one of the "loud raspy exhaust" horror stories. I have an 89 SC and I was running low on funds when I started modding my SC and wanted bang for the buck. So what do I do? I get a 10% aluminum pulley, gut the cats, delete the res, and remove the mufflers and weld in turn-down tips.

This car is by far one of the loudest thunderbirds I thing Ive ever heard. Given, I do like the sound but theres a rasp at about 2500 thats pretty annoying. Im planning to just weld in a Flowmaster single stage and see how well that gets rid of it. Other than that it sounds good and sounds like a V8 sitting still idling. Im not the type to go for quiet exhaust... it just isnt me :-P Let em keep pullin' me over lol.

01-26-2005, 04:40 PM
ok my exhaust is as follows and i love it, its not too loud and it has a lil rumble to it, but i do have a cam. i ahve 2.25 from the manifolds to end of the m5r2 trans, where there is a 2 in 1 out magnaflow res, and that goes to the rear where it splits again into 2 magnaflow mufflers. the mufflers arent loud, but when i did not have the resonator the car sounds really loud and like ***...i do not have cats, but hi flow ones will not affect the sound of it much more than mine sounds like...its loud when you want it to be with the foot on the floor, but i like it and it sure as hell doent sound like a honda. you will be able to hear the blower more with exhaust and intake.

01-26-2005, 08:28 PM
Well my exhaust has a little rumble too but not loud. I have the stock manifolds with the cats but where the y pipe meets i replaced the other half. Its a 3" all the way back to 2 2.5 pipes with dynaflow mufflers. Oh and no resignater. The car sounds pretty good but i knoe there is more to improve on.

01-29-2005, 02:13 AM
Yeah, i'm gonna have enough trouble stayin away from the 5-0 with a cowl hood and headlight covers. I should now at least have a quiet car to make it at least sound like a sleeper...I've pretty much decided that i'm gonna go true dual with two cats, but i can't decide on a muffler. I had the flowmaster 40's on my car with the stock everything else and it definitely didn't have the sound i was looking for. I was thinking of maybe tryin to get some Ravin mufflers, has anyone had any experience with these mufflers? from the cross-section they provide, they seem to be a good candidate for a low rumble. Here's the website i found...