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pbdevastator
04-19-2009, 02:20 PM
i have a 90' sc with a 5% od pulley and all the belts are practically new. In high rmps, it seems like the car is cutting out, not too bad in 1st gear or 3rd, but 2nd gear its the worst. I just got the car back from having the transmission rebuilt. before that it was doing teh same thing in second gear, but it was the entire gear that was messed up and od was gone too. so i really believe the belt is slipping for some reason. or is it likely i need to replace the tension spring? i did notice the supercharger tension when i try to wobble it or whatever does have a little give. any help or opinions on this would be appreciated.

pbdevastator
04-19-2009, 02:29 PM
think it has something to do with my ignition or fuel delivery too?

fturner
04-19-2009, 02:31 PM
The only thing that belt slip would do is cause less boost. Its highly doubtful it would cause the car to miss at all, unless the blower was completely stopping and starting.

I'd start looking at plugs and wires causing the miss.

Fraser

Young-SC-Owner
04-19-2009, 04:30 PM
Didnt you post this exact problem a few weeks back?

Id vote for spark blowout, higher boost = more dense air, weak wires/plugs sound like the issue

pbdevastator
04-19-2009, 06:58 PM
no it wasn't me that posted about this a couple weeks ago. i dont think im describing what is going on very well. In the higher rmp band only, it cuts out and in over and over really fast(cuts in and out like 2 or 3 times per second) until it shifts, then once it reaches higher rmp agian same thing. Really feels more like a hesitation. First gear is fine, barely can notice it, 2nd gear after like 65 its really bad, then in third gear which i didn't experiment with that much cause i have to go over 100mph for it to act up there. Hopefully this better describes what is going on.

fturner
04-19-2009, 07:10 PM
Ignition problem. Either you have a spark plug thats bad, and/or wires. These cars are very sensitive to ignition issues and what normally won't show up normal driving, will when under boost.

The more boost is made increases the resistance for the spark to jump across. You may need to close up the gap a to about 0.040 if your running OD on the blower. But again, check all the wires and plugs. If the wires are several years old, then its probably time to replace them. Stock wires are good for a car that still mostly stock.


Fraser

RedSC93
04-19-2009, 07:44 PM
I also would suggest pulling the plugs and check the gap and check closely at the porcelain around the plug for cracks.


Jerry

pbdevastator
04-19-2009, 07:54 PM
Ok thanks a lot guys, multible people here and other people I have talked too are all saying the same thing. Even though i don't have a lot of miles on the current plugs/wires, they have been on there for several years so ill just replace everything. Think ill do the tension springs too while I'm at it.

David Neibert
04-20-2009, 12:14 AM
What rpms does it happen ? How much boost is the gauge showing when it happens ?

David

pbdevastator
04-21-2009, 08:33 PM
starts between the 3500 to 4000rmp range, and it shifts at 5000 rpm. as for the boost gauge, i never really looked at it while test driving this, i was more worried at what rpm and speed the tranny was shifting. I did multible speed runs on the country roads, i had 1 run where nothing happen, the others car acted up. 2nd gear was the most noticable. Ill take the car out again and look at the boost meter when/if it stops raining.

David Neibert
04-23-2009, 09:03 AM
As was already posted...it's most likely a bad plug or wire.

David

pbdevastator
04-25-2009, 05:29 PM
ok the problem is solved car working perfectly now. You guys were definately in the right area. Though it wasn't a bad plug or wire, lol popped the hood and found that one of the wires was barely on the plug. go figure right?