4bbl carb to 2bbl intake??
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More Turbo
Joined: Jan 2001
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From: New England
4bbl carb to 2bbl intake??
I am about to get my heads back from shop. I am considering putting my stock intake back on, but I want to use my Edelbrock carb. Can I do this?? I am just hoping that the heads will resolve the lean condition in a few cylinders I am experiencing. My current heads were on a 400 that locked up at 75mph, breaking cam in half. I have tried everything from changing carbs to changing intake gaskets. to no avail. (PS I replaced motor with fresh rebuild)
You think my new heads with three angle valve job will clear this lean condition up? It would run like crap untill it warmed up, and even then it was kinda weak.
I am running a rebuilt 400 with 30k on it. The heads were like I said, used from the blown motor, and the machinist ground .025 off of them for a compression boost supposedly. Do you think this caused my intake not to seal right?
I have an edelbrock performer intake BTW.
You think my new heads with three angle valve job will clear this lean condition up? It would run like crap untill it warmed up, and even then it was kinda weak.
I am running a rebuilt 400 with 30k on it. The heads were like I said, used from the blown motor, and the machinist ground .025 off of them for a compression boost supposedly. Do you think this caused my intake not to seal right?
I have an edelbrock performer intake BTW.
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Joined: Dec 2003
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If the head has been milled that much the valve geometry needs to be checked. Grinding valves and seats also make the stems stick out of the top of the head more. The machinist should grind the stems to compensate for that though. A hydraulic lifter needs to be set up with the plunger in the correct range inside the lifter. You can get shorter pushrods or adjustable rockers or shim under the rockers if that is what the problem is.
I rebuilt a 390 once that would start and then immediately die. It acted like a massive vacuum leak. Turned out to be caused by the head being surfaced to many times which effectively made the pushrods to long. As soon as the engine started the lifters would pump up and hold the valves open. I fixed it by shimming the rocker stands up with two layers of Budweiser can.
I rebuilt a 390 once that would start and then immediately die. It acted like a massive vacuum leak. Turned out to be caused by the head being surfaced to many times which effectively made the pushrods to long. As soon as the engine started the lifters would pump up and hold the valves open. I fixed it by shimming the rocker stands up with two layers of Budweiser can.
Posting Guru
Joined: Aug 2000
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From: (near) Denver USA
Whichever intake you use has to be adjusted (by milling the head sealing surfaces, and possibly the end seal surfaces) to fit the milled heads.
I wouldn't use the stock 2V intake with a 4V carb.
I wouldn't use the stock 2V intake with a 4V carb.
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More Turbo
Joined: Jan 2001
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From: New England
ok, I had a gut feeling that was a problem, but it did run (crappy) I have had NO time to do a head swap lately with school/business etc.
But Im gonna find time.
I replaced head gasket on my 79 OLDS 307 V8 this past weekend and had so much fun painting the valve covers, cleaning intake, carb, bolts etc.
I forgot how much fun it CAN be. And besides in south ttexas you really wanna do you biggie projects in fall winter spring.
Thanks guys, I should hear from the machinist today on the fate of a pair of heads I brought him. (heads were not used since 1986, have 82k original miles)
But Im gonna find time.
I replaced head gasket on my 79 OLDS 307 V8 this past weekend and had so much fun painting the valve covers, cleaning intake, carb, bolts etc.
I forgot how much fun it CAN be. And besides in south ttexas you really wanna do you biggie projects in fall winter spring.
Thanks guys, I should hear from the machinist today on the fate of a pair of heads I brought him. (heads were not used since 1986, have 82k original miles)
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