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Discussion Starter #1
Just finished up installing some new Trickflow cylinder heads. They are now sitting atop a 350 with a TPI. THough I do not know the specifics of the cam, I know its fairly mild from its idle and powerband before the head swap.

It will start and run smooth, and then a little rough but for the most part smooth above 1000 rpm. Anything below 850 or so and the engine shuts off. I have checked for vacuum leaks and there are non. My vacuum guage shows 15 inches of vacuum which is pretty much where it was at before the head swap. Timing is set at 6 as this is a stock setting for a TPI. The comupter takes over after that. Fuel pressure seems great for it at 48 (I can adjust this and will to help out once things are set). If I take out the pcv and have the line open, it climbs in RPM's.

There is no backfiring or poping and like I said it seems to run great above 900-1000 RPM or so. Is it possible my cam is bigger than I thought and the new heads (which replaced stock junker heads) are causing the cam to act bigger? In drive it will die at anything less than 850RPM.

Any ideas?
 

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you probably know just what i know(or more). here are a few ideas. double check everthying . like your base carb settings.

when you set the timming do you half to jump the service connector? on ford there is the spout connector. did you have a similar procedure to do?

you may have to recalibrate the computer. or let it adjust with a idle relearn

have you tried increasing the fuel psi just to see what happens?

pull the vacuum line off the psi regulator and plug it.
 

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Discussion Starter #4
I just changed the heads and went to 1.6 Roller rockers. I would hope the heads flow a lot better than the stock heads lol. The timing was set in the correct procedure however I am going to play with it some more and see what it likes. I just feel that having to idle in drive at 850RPM means something is a miss. It did have to idle fairly high before. Is it possible the new heads and airflow mean it will have to idle higher now? Still seems like something is amiss.

Gone is fuel injected so no carb to mess with. I will open the butterflies a little more but the Idle Air control valve (which is new) should take care of idle air.
 

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Siggy-Freud,

With the addition of the 1.6 rockers I think the valve overlap is making your engine run as though it has a larger lift cam.
I would leave well enough alone and drive the car a few weeks and then check things out again.

Just My .02
Scholman
 

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Engine just stops??

What do you mean the engine just stops. Give me more details. Does it try to stay alive or below 850 and gone!
By changine the rocker ratios you may need to play with the idle fuel. Also look at the MAP readings are they the same with the new set up??
 

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Discussion Starter #7
This post was started by me about 4-5 months ago. It required a reworking of the computer chip as well as playing with the IAC settings.
 
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