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Old 03-13-2010, 01:35 PM   #76
bitchin85
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Re: New Parts, New PROBLEMS!!!

Should I cut aholefor theheat crossover? And I know about getting it running right first but I figured while I have the intake off, and I have a new double roller timing chain and new cpover, I might as well put the cam in it. I should be able to use the stock springs right? Its a pretty mild cam..
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Old 03-13-2010, 11:35 PM   #77
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Re: New Parts, New PROBLEMS!!!

The heat (exhaust crossover) is very important. The exhaust crosses under the intake to heat up the intake port just below the carburator. This is what vaporizes the gas. Without the gas being vaporized it won't burn. If this is an old manifold the crossover may be plugged or worse yet cracked between the exhaust crossover and the intake port.
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Old 03-14-2010, 12:54 AM   #78
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Re: New Parts, New PROBLEMS!!!

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Originally Posted by 1LowToy View Post
The heat (exhaust crossover) is very important. The exhaust crosses under the intake to heat up the intake port just below the carburator. This is what vaporizes the gas. Without the gas being vaporized it won't burn. If this is an old manifold the crossover may be plugged or worse yet cracked between the exhaust crossover and the intake port.
Many aftermarket heads in fact do not even have the crossover so imho its not real important and just for cold climate operation because it is not good in summer months and I even run a carb heat insulator and it helps a lot.

I humbly disagree on it vaporizing the gas never heard that before.

If you have the hole in head and manifold you may as well use it cause even if you block it off it will eventually burn thru.

My Edelbrock RPM heads don't have a crossover and I believe AFR and possibly others do not have it either so its not crucial to operation.
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Old 03-14-2010, 01:01 AM   #79
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Re: New Parts, New PROBLEMS!!!

ill just cut the hole for the heat riser. and the more i drive it, and the more stuff i rule out, the more i think that my intake manifold gaskets arent sealed.. hard starts..bad mileage, no balls, missing.. i guess ill find out for sure when it all goes back together. so nobody knows anything about my cam? stock springs? .....i hope
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Old 03-14-2010, 01:10 AM   #80
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Re: New Parts, New PROBLEMS!!!

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ill just cut the hole for the heat riser. and the more i drive it, and the more stuff i rule out, the more i think that my intake manifold gaskets arent sealed.. hard starts..bad mileage, no balls, missing.. i guess ill find out for sure when it all goes back together. so nobody knows anything about my cam? stock springs? .....i hope
Whats the lift on that cam? How old are the springs on your heads? Check that the springs don't bind for sure. Other than that the cam should say what spring pressures and heights are needed.
There is no to know whether or not the springs you have will be good enough unless you actually check them with the right equipment. This usually requires special tools.

A stock 350 cam has these measurements.

-929 hi-cam at 195/202, 112/108, .390"/.410" lift

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Old 03-14-2010, 01:14 AM   #81
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Re: New Parts, New PROBLEMS!!!

http://www.summitracing.com/parts/SUM-1102/

here she is.. the heads were rebuilt in 04 when they put the 350 in. there clean as they were factory..and the motor has about 30,000 since the rebuild

it has the stock style dual valve springs
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Old 03-14-2010, 01:16 AM   #82
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Re: New Parts, New PROBLEMS!!!

The over rich carb, the gas smell, the cloud of gas, the backfires. I have the same carb that I had to tear apart and reset the float to cure the rich problem. I know you said you aren't showing any arcing but have you put an ohm meter on the wires and checked them? That could give you a miss from an internal wire break that isn't showing through the jacket. I do controls for a living and you would be shocked at how often new wire can be broken inside the jacket. It makes finding a problem a real pain.
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Old 03-14-2010, 01:17 AM   #83
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Re: New Parts, New PROBLEMS!!!

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Originally Posted by *****in85 View Post
http://www.summitracing.com/parts/SUM-1102/

here she is.. the heads were rebuilt in 04 when they put the 350 in. there clean as they were factory..and the motor has about 30,000 since the rebuild

it has the stock style dual valve springs
I see that cam is not much bigger than stock it may very well be just fine then.
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Old 03-14-2010, 01:19 AM   #84
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Re: New Parts, New PROBLEMS!!!

rthats what i thought. im not looking to build a ten second drag truck, just a solid DD with a little a$$.. and for the wires, i have not put an ohm meter on them but i know a guy who has all that stuff and ill have to check them soon. as for the floats, were yours set at 7/16?
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Old 03-14-2010, 01:29 AM   #85
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Re: New Parts, New PROBLEMS!!!

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rthats what i thought. im not looking to build a ten second drag truck, just a solid DD with a little a$$.. and for the wires, i have not put an ohm meter on them but i know a guy who has all that stuff and ill have to check them soon. as for the floats, were yours set at 7/16?
Yea I believe my Edelbrock carb was set at 7/16. Stock springs are actually single w/ dampner not really dual valvesprings.

Ron White is cool btw he gave me a nice fat tip once for running some errands for him and walking his dogs.

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Old 03-14-2010, 01:30 AM   #86
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Re: New Parts, New PROBLEMS!!!

im going to pop the lid off tomorow and make sure thats whhere theyre at
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Old 03-14-2010, 01:40 AM   #87
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Re: New Parts, New PROBLEMS!!!

I don't actually remember what my float was set at. I used the .pdf from Edelbrock to set it, that was three years ago. I'm actually considering chunking the thing and getting an Avenger anyway.

As for ohm's on the wire, just make sure they all ohm out the same. I'm sure that somewhere there is a spec for what the resistance should be but I don't know where to find it.
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