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Discussion Starter #1
Recently installed the bb kit on a stock motor 95 cobra. 1st problem is coolant system is pressurizing for some reason and spraying coolant and the upper radiator hose is rock hard. I took the t-stat out thinking that might be the culprit but no, same results. car is not running hot so i don't get it. Oil looks good as new so I don't know whats going onm there.
2nd problem is cannot go full throttle, if you do it breaks up and falls flat on its face. I'm running stock plugs but I gapped them down to .025 and added a msd coil still same result. For fuel I added a 255 intank, 42lb inj, and a blow through pro-m maf, stock fpr. Timing is locked at 20 spout out.
3rd problem is the car will start and idle fine when cold, however after warm up it cuts off every time you depress the clutch as if coming to a stop. There are no check engine lights or anything so I'm lost on that one too.
Any help would be greatly appreciated, would love to cruise this weekend but don't look like its gonna happen.
 

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most of the time when it is pressurising the coloant system is a headgasket problem(just went through the same problem).

The 42's are fine, really sounds like the car needs a tune.. some get them to run good just seting timing with the spout out, but the motor needs more timming down low.. if you take it and have chip done they can have it pull the timing in the chip..Im sure that is where most of the idle and cutting off problem is..

also get a better(colder plug) and set the gap around 25, and a MSD box will also help the spark blow out..
 

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i agree with the above. It sounds like a headgasket but not a coolant leaking problem obviously. It can still pressurize the system with the gasses thru the cooling system I had this problem with a nitrous car that popped a gasket but didnt leak. I would do a compression test.
 

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Discussion Starter #7
I went out droved the car again for about 5 miles, tried getting on it a little and above 4k it busts up, feels like spark blow out so I'm going today and get one range colder plug try a .023 gap and seee what happens. The coolant did not pressurize on this drive so I don't know what the heck could be going on. Maybe an air pocket in the system? need to find the best way to burp it, will be searching here shortly for that.
I will be getting a chip burned for it soon enough, but I know it can be ran safely with a homemade tune for now and thats where I'm trying to be at the moment.
 

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I can't tune it from here, your trying to see boost in a non tuned car, and probably blew the hg's. You didn't say anything about checking for a hg, but your still trying to play with it when nothing is going to change or to get better with popped gaskets. How much enlightenment were you looking for ? You shouldn't be blowing out .025 gap at even 14 psi. Can't tell you if your have the right plug range in there because you didn't mention how much boost. Pressurizing the cooling system isn't caused by air in the system. If you lift a head, you don't always see oil mixed, or over heating.
 

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I also had stalling issues after warm up, but a tune at my local dyno fixed all that now im safe and fast. oh and no stalling.
 

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You need a tune.

I have a homebuilt T70 kit on my car. It idles and drives just like stock.. till you lay into the pedal and it's smoking the tires at 60mph..

Locking timing should just be used to GET TO the dyno. Not actually drive around on for months. You'd be surprised at how much the timing fluctuates from start-up, idling, cruising, deacel and WOT. It's vary's a ton, and being locked doesn't help at all.
 

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I can't tune it from here, your trying to see boost in a non tuned car, and probably blew the hg's. You didn't say anything about checking for a hg, but your still trying to play with it when nothing is going to change or to get better with popped gaskets. How much enlightenment were you looking for ? You shouldn't be blowing out .025 gap at even 14 psi. Can't tell you if your have the right plug range in there because you didn't mention how much boost. Pressurizing the cooling system isn't caused by air in the system. If you lift a head, you don't always see oil mixed, or over heating.
No offense to you, you simply chimed in and said your tune sucks. Other than post count why even bother. I wasn't asking for tuning advice. I know how to get a base tune to get to the dyno which is why I locked timing. My last blown 351 coupe ran a best of 10.8 with no tune and locked timing so I know it can and has been done thousands of times. The BB kit comes with a 6psi spring and I haven't changed it out or seen any boost from the turbo yet so its highly unlikely that I would have blown a head gasket at this point.
Now, I read up on air in the system and apparantly theres something to it. I followed the procedure someone explained and the pressurizing is gone. After that I put autolite 103 plugs gapped down to .023 and can go full throttle now will very minimal breakup.Thats two heat ranges colder than stock so maybe I need to bring it back up to one heat range colder. I clocked the Pro-m a little and that seemed to clear up most of the cutting out. This is the kind of enlightenment I was posting for, thanks ragtopman for the p.m. and great information.
 
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