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Old 02-28-2013, 12:20 PM
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cobalt327 cobalt327 is offline
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There are guys who are already experts and others who need a little help, so it's hard to know where everyone fits at first. So if this is old news, just disregard it.
Quote:
Originally Posted by actmobmar View Post
i've never driven it so i don't know how much vacuum it has, and the car itself hasn't been driven since 1988. when i broke the cam in i ran it on an external fuel source, and the car wouldn't idle-the carb was dirty from all the years sitting, and i didn't want to rebuild it at the time because i still have alot of work to do on the car-suspension, brakes,etc. i'm stiil on the fence about stroking it, it sounds as though i can meet my goals without doing it.
You can run 12's at 400 ci providing you can get enough traction, the gear ratio is aggressive enough to get the car off the line good, and you are good at shifting the manual box. The first 60' mean a lot when talking about drag racing ET, so you're right on target w/a 3.73 rear gear combined w/the Tremec 600 transmission.

Stroking it would be great if it's in the budget.

Quote:
i plan on pulling the heads this weekend, but at a minimum i will replace the rods w/ eagles and port the heads.
Good deal. This will give you the opportunity to measure how far down the cylinder the pistons are at TDC (piston deck clearance), as well as to see what the piston type (forged or cast), and design (flat top/dished) is as well as the number of valve reliefs (some rebuilder-type pistons have 8 valve reliefs to accommodate both early and later valve angle, this adds volume to the piston "dish" over what a 4 valve relief piston has). Obviously this will be the time to CC the combustion chambers as well.

The reason for all this measuring is to know what the static and dynamic compression ratio is, as well as the quench distance. A page w/links to dynamic CR calculators is here. Other areas of the valve train that need to be verified can be found at the links below.

The following may be putting the cart before the horse, but if you're considering swapping to 1.6:1 or 1.65:1 ratio rocker arms, check the fit/relieve the pushrod holes to allow the pushrods to fit correctly while you have the heads off. Not necessarily that I think you need more lift, but just in case.

Valve train points to check
Valve train geometry
Valve spring installed height
Adjusting solid lifters
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