Hi Everyone,
This my first post on here, though I've been lurking awhile.
I have just resurrected my '89 Super Coupe 5-speed after a six year hiatus. Worst thing was cleaning up the mice mess. But at any rate, I have the car running again and not too badly at that. Car has 155,000 miles on it, and I've owned it since 1994; I bought it as the second owner and it was still under warranty.
Ok, the thing has been a bear to work on ever since I got it. Changing plugs is one of the most horrific jobs I've ever done to a car.
I have been thinking of doing a V8 conversion. I have read through a bunch of threads on here. XR7 Dave has offered some great commentary.
Anyway, here is my idea:
Remove the V6 mill and M5.
Replace it with a Windsor stroker engine. I was originally thinking a 427 built on a Dart block with AFR 205 heads. This would be backed by a Tremec T-56 Magnum transmission. I have since read that a 408 is a very common build and you can do that with a stock block (late 60's block with heavier walls) and it will hold up OK. But at any rate, I was thinking somewhere around a 408 or 427. By removing the blower, and intercooler, and already having an iron block with aluminum headed engine, I think an iron block aluminum headed V8 would come out about the same weight as the original engine+blower system, so it shouldn't mess up the handling. I'm still working out the details, but I think the Dart block at 427 cubes, all forged reciprocating assembly, AFR 205 heads, Victor Junior intake, and the appropriate induction system.
I would prefer fuel injection, but the Edelbrock stand alone kit was in the $3300 range and that's getting up there. I'm not sure how to make the EEC IV for a six cylinder work with an 8. So, a properly tuned Holley 750 might do for now. Actually, I have a new one in the box right now...
Problems I see: How strong is the 8.8 IRS setup? My buddy says he's seen the half shafts just disentigrate when you start pumping real power through them. I see you can get a girdle to beef up the stiffness of the diff itself. What about the stub shafts?
I don't plan on doing any crazy mods to the body work, so really about a 245 would be the widest tire I could fit on it. Being traction limited, wouldn't that help save the half shafts?
I'd be going from 210hp and 325 ft-lbs to 500 and 500. If I took it easy in 1st and didn't really start getting on it until 2nd or 3rd, wouldn't that really help out?
Just the same, I don't want to have to worry about it breaking. So, after the engine/trans swap, what would I need to look at as far as keeping the rest of the car together?
I really like the way this car handles. Right before I parked it, I installed a Tokiko performance handling kit for it that works with the ride control. Where it was soft and firm before, now it's firm and harsh. We also used some different alignment settings that dialed out some of the understeer. The car handles great. And as much as I love big blocks, I don't want the weight messing up the handling.
So anyway, I'm strongly considering a big inch Windsor (I don't want a 5.0....). It looks totally doable to me. But I don't know how weak the rest of it is.
Another route might just be a nicely built 351 that is still a 351, if the rest of the driveline can't take 408 or more without $10K worth of add ons. But if a girdle and stout half shafts would suffice, I'd really like to do a 427 small block.
Can you guys help me?
Thank you,
Jim
'89 SC 5-speed
This my first post on here, though I've been lurking awhile.
I have just resurrected my '89 Super Coupe 5-speed after a six year hiatus. Worst thing was cleaning up the mice mess. But at any rate, I have the car running again and not too badly at that. Car has 155,000 miles on it, and I've owned it since 1994; I bought it as the second owner and it was still under warranty.
Ok, the thing has been a bear to work on ever since I got it. Changing plugs is one of the most horrific jobs I've ever done to a car.
I have been thinking of doing a V8 conversion. I have read through a bunch of threads on here. XR7 Dave has offered some great commentary.
Anyway, here is my idea:
Remove the V6 mill and M5.
Replace it with a Windsor stroker engine. I was originally thinking a 427 built on a Dart block with AFR 205 heads. This would be backed by a Tremec T-56 Magnum transmission. I have since read that a 408 is a very common build and you can do that with a stock block (late 60's block with heavier walls) and it will hold up OK. But at any rate, I was thinking somewhere around a 408 or 427. By removing the blower, and intercooler, and already having an iron block with aluminum headed engine, I think an iron block aluminum headed V8 would come out about the same weight as the original engine+blower system, so it shouldn't mess up the handling. I'm still working out the details, but I think the Dart block at 427 cubes, all forged reciprocating assembly, AFR 205 heads, Victor Junior intake, and the appropriate induction system.
I would prefer fuel injection, but the Edelbrock stand alone kit was in the $3300 range and that's getting up there. I'm not sure how to make the EEC IV for a six cylinder work with an 8. So, a properly tuned Holley 750 might do for now. Actually, I have a new one in the box right now...
Problems I see: How strong is the 8.8 IRS setup? My buddy says he's seen the half shafts just disentigrate when you start pumping real power through them. I see you can get a girdle to beef up the stiffness of the diff itself. What about the stub shafts?
I don't plan on doing any crazy mods to the body work, so really about a 245 would be the widest tire I could fit on it. Being traction limited, wouldn't that help save the half shafts?
I'd be going from 210hp and 325 ft-lbs to 500 and 500. If I took it easy in 1st and didn't really start getting on it until 2nd or 3rd, wouldn't that really help out?
Just the same, I don't want to have to worry about it breaking. So, after the engine/trans swap, what would I need to look at as far as keeping the rest of the car together?
I really like the way this car handles. Right before I parked it, I installed a Tokiko performance handling kit for it that works with the ride control. Where it was soft and firm before, now it's firm and harsh. We also used some different alignment settings that dialed out some of the understeer. The car handles great. And as much as I love big blocks, I don't want the weight messing up the handling.
So anyway, I'm strongly considering a big inch Windsor (I don't want a 5.0....). It looks totally doable to me. But I don't know how weak the rest of it is.
Another route might just be a nicely built 351 that is still a 351, if the rest of the driveline can't take 408 or more without $10K worth of add ons. But if a girdle and stout half shafts would suffice, I'd really like to do a 427 small block.
Can you guys help me?
Thank you,
Jim
'89 SC 5-speed
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