So, I recently came across a set of e7's someone gave me. They were ported and have a larger intake valve. Has anyone used split rocker ratios to increase the flow on the exhaust side? I would think the added lift would help it without having to spend too much money to increase the valve sizes, but I've got no experience with how split ratios would effect flow rates. I've got a b303 and a 600 carb, block is stock.
Engine Split ratio rockers
- Thread starter FoxDudeMan
- Start date
It seems I remember many years ago some using 1.7 rockers on the exhaust and 1.6 on the intake but I don't remember what cams or what the results were.
I figured since the b303 has equal durations on the intake and exhaust, and the limiting factor on the stock heads was, among other things, the exhaust flow, it would definitely help. I just don't know how much it would help. I know the best way would be to put some on and just try it out, but I'm trying to not spend any money on the heads.
- Mar 2, 2015
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Split duration rockers will help to a degree. I used to run them on an e303....and ran them on a stock cam. Ford always restricted the exhaust side. Exhaust port porting and split rockers will show a difference with some cams. No first hand experience using them on a b cam. I don't know how much lift that cam has off hand. Will need to check piston to valve clearance.
The spec sheet says 480 I think my total at the moment is like 512 or something close with the stock rockers. With 1.7s I know I'll need pushrods for the exhaust ports, and that should put me around 550 lift or something maybe. Anybody have any idea of the lift where valve clearance becomes an issue? Also if anybody has got a set of 1.7 non rollers for sale that would be cool.
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