Durability questions on SC's/XR7's

FineLineMtrSprt

Registered User
OK guys im looking to get another SC or XR7..but prolly a super coupe. I have missed mine ever since i had to sell it back in 99 after having it only 8 months. It was a bone stck 90 auto..silver with charcol cloth..JBL system and Sunroof..the kick was it had 2 owners and 36k org miles when i got it..everything was org. on it and it was spotless. Well since i have to sell my lightning im considering another SC. But since i neevr got to mod mine i have some questions. The rear halfshafts...what are the stock ones good to power and et wise. What gears coem in them stock..3.08's? I see lots of guys going to 3.27's....why not 3.73's or 4.10's? and do normal 8.8 gear sets work in them? Also what years are affected by the head gasket problem?

I do remember the stock HEATon was just that..a heating monster...my m112 on the lightning is bad enough....what do you do to compete that without buying a 1500 buck Spearco? Anyone made a good sounding exhaust for these yet...and im not doing flows...lol...anyone try Spintech mufflers? And does it still stand that if you remove the resonator these tings get nasty sounding...in a bad way?

The shocks....if you have the electronicly adjustable suspension....are the electronics ont he shock....or can you use any shock to repalce them. I know this is a lot to take in...but i just wanna know what im getting myself into. I did 4 months of research before i got my lightning lol.
Thanks, Vince
 
Welcome back.

A few things.....

1. I've seen 12's on stock half shafts, although the RAXLES are a good upgrade because if you get too much traction at those power levels **** will break.

2. 3.27:1 is the stock ratio in an 89-93 Auto car, 2.73:1 in all 5-speeds, and 3.31:1 in 94/95 autos. Most auto guys go up to 3.73's and the 5-speeds go to 3.27's. I have the 3.27's in my 5-speed.

3. I happen to like the sound of my flowmaster exhaust system on my 5-speed car w/o cats, but I hear the SCP big dog sounds pretty good also. If you ditch a resonator completely it will sound like ***, but it will flow some air.

4. Technically all years can suffer from head gasket problems. Cast iron block with aluminum heads is just asking for trouble. Especially since these heads only have 8 bolts per head, they can lift under high boost. A good multi-layer steel gasket may be the best option. I run Fel-Pro blue stripes on mine and they have been great so far.

5. A Magnum Powers front mount kit seems to be the best option unless you want to buy an IC and have someone custom bend you some pipe. I believe they are around $1200 for the kit. Go to www.magnumpowers.com they have the best ported M90 blowers and inlet plenums. Serious power from an M90.

6. The shocks have a valve in the top of the threaded piece on top. An actuator clips to the shock tower and the top of the shock. It will flip the valve 90 degrees to change from firm to soft. If you go with aftermarket shocks, just unclip and unplug the actuators and save them for later. Koni makes a damn fine adjustable shock, although you have to manually twist the valve on top with your hand. I believe it has 9 selections.

7. If you have any more questions shoot me a private message.

8. If you want to skip blowing money on a ported M90 and pullies/plenums/raised tops, etc... you might want to get in touch with XR7Dave he sells an autorotor supercharger kit for these cars. On a stock 5-speed with only exhaust and a front mount intercooler it made almost 300 at the wheels but was running out of fuel on the stock pump. He made 440-450 rear wheel horsepower recently on a stock bottom end. It has ported and welded big valve heads, a cam, headers, autorotor, front mount, and a modified intake manifold. So it can be done on stock pistons/rods/crank and its a pretty easy recipe to duplicate if you have the money. If you were to build it like that you'd spend less than some of the guys who are in the 300 rwhp range but hey they made a lot of power when parts were hard to come by. Now just about everyone can have a 300 rwhp SC with commonly available parts. Times are changing and we are really pushing the envelope with these cars. Coy Miller ran a 10.85@129 last fall.
 
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Scott-

As an FYI I have been using SCE Pro Copper gaskets in stock hardness, .043 thickness without any issues at all. They seal very well, and I have been running a 10% pulley on the supercharger since a year ago, and the guys in the area can tell you I flog it on a regular basis-and have done so with no blown HGs.

I went with SCE because they are used on 7000HP dragsters without many problems-I figured they could stand up to 230hp :D
 
I run 10% overdrives on both of my SC's. As long as I am moving the temp stays fine. I have the fans on a switch incase the temp goes up.

I did overheat the hell out of my engine last winter right after I put the gaskets on it in the fall. I unplugged the fan since it was making some noise. I let the car warm up while I got ready for work. Came out and the temp gauge was pegged. I shut the engine off, and plugged the fan it and let it run. When I started the car 10 minutes later the temp had went down, and on my way to work it returned to its normally cold operating temps. I had coolant boiling and everything when I came outside. It has ran great since. The gaskets held and didn't blow I was amazed.
 
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