Engine combo question....

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Engine combo question....

Postby rjones35 » Fri Jan 17, 2020 1:20 pm

A question for some of you engine guys. Working on a plan for the engine in my vega, itll be a fairly mild driver prostreet car. I'm not looking to go racing, I do want it to sound healthy and be dependable. So far I've got a 383 short block in the works. Flat top pistons, I figure if I keep it 10-10.5 :1 I'll be good as far as gas goes. My buddy will be helping me put it all together. Thinking about those heads from skip white, 700.00 or whatever they are, looking at a comp cams 306 hydraulic roller, and a performer rpm airgap manifold. I'll be running a th350, I don't have a convertor yet, or rear gear, so that can be whatever. Does this sound like I'm on the right track?
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Re: Engine combo question....

Postby cjbiagi » Fri Jan 17, 2020 3:05 pm

Not familiar with Skip White heads but looking at his website looks like they are AFR heads? Sounds like you are on the right track assuming the rest of the car will be built to handle the power.
Clyde.........75 Monza 2+2
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Re: Engine combo question....

Postby rjones35 » Fri Jan 17, 2020 3:36 pm

cjbiagi wrote:Not familiar with Skip White heads but looking at his website looks like they are AFR heads? Sounds like you are on the right track assuming the rest of the car will be built to handle the power.



Right on, thanks! I think the skip white heads are imports from somewhere, but supposedly are pretty decent. Car should handle it okay, I hope!!
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Re: Engine combo question....

Postby Smiley » Sat Jan 18, 2020 12:01 am

Solvent test all the valves before using the heads, mixed reports on the valve job quality
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Re: Engine combo question....

Postby rjones35 » Sat Jan 18, 2020 6:29 am

Smiley wrote:Solvent test all the valves before using the heads, mixed reports on the valve job quality


Will do, thanks!!
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Re: Engine combo question....

Postby rjones35 » Sat Jan 18, 2020 8:15 pm

Another question - the block I have is one I got from Summit and one that will take the bolt on cam thrust plate. My buddy says since I have the option I should do that, which is fine, it sounds like a good idea, but seems like it narrows down my cam choices. I know I can get something ground, but is that cam thrust plate that big of a deal, compared to the "old" way with a thrust bumper?
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Re: Engine combo question....

Postby Smiley » Sun Jan 19, 2020 3:17 am

If you use a roller cam use the thrust plate or a bumper, flat tappets have opposing tapers on the lobes so they don't move front too rear like a roller cam. Later blocks use plastic timing covers with a crank sensor hole.
Bumpers should be used with steel covers.
If your new block is a one piece rear main Kevco Racing makes Vega pans for it.
Last edited by Smiley on Sun Jan 19, 2020 3:29 am, edited 1 time in total.
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Re: Engine combo question....

Postby rjones35 » Sun Jan 19, 2020 3:25 am

Smiley wrote:If you use a roller cam use the thrust plate.
If your new block is a one piece rear main Kevco Racing makes Vega pans for it.


Thanks! That's good to know. I'll be needing a pan.
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Re: Engine combo question....

Postby rjones35 » Thu Jan 23, 2020 9:12 pm

Can one of you guys that's smarter than I am tell me the difference between these two cams? I see the different numbers, but what does it actually mean as far as idle, rpm range, etc.... They seem pretty similar to me.

.510/.520 280/288 230/236@.050 110 lobe separation

.502/.510 280/288 224/230 @.050 112 lobe separation
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Re: Engine combo question....

Postby cosvega76 » Fri Jan 24, 2020 2:08 pm

The second cam has a shorter intake duration and wider lobe separation, so it will idle a little better with a wider torque range. The first cam will have lumpy idle with its torque range tilted toward the lower side with its narrower lobe separation, but low end torque won't be its strong point. If you are building a street car, I would steer you toward the second cam.


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Re: Engine combo question....

Postby rjones35 » Fri Jan 24, 2020 2:12 pm

cosvega76 wrote:The second cam has a shorter intake duration and wider lobe separation, so it will idle a little better with a wider torque range. The first cam will have lumpy idle with its torque range tilted toward the lower side with its narrower lobe separation, but low end torque won't be its strong point. If you are building a street car, I would steer you toward the second cam.


Chuck



Thanks Chuck!!
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