Ramshead Exhaust on 220cc Aluminum Heads?

[72peace]

Is it safe to use a stock iron ramhead exhaust against aluminum heads or will the metals together cause corrosion?
Also on an unrelated note, i've been catching flack for using 220cc heads on a daily driver and have been urged to switch to a 185-195cc, does anyone have any thoughts on this issue?


350 rebuilt w/mild cam
220cc aluminum heads
edey performer intake
edey 650cfm carb
Daily Driver...

Cheers,

[406 Q-ship]

On a 350.....yeap those heads areWAYtoo big

If your going to run that big of a port in the head, why oh why would you not be installing 2" primary headers if bigger is better. Your combination is going to be way lazy in lower RPM range for torque. Forget the Horsepower numbers and build the engine for torque, that is what really moves the vehicle anyway.

[bubba353z]

The exhaust gasket prevents them from actually touching, but either way it doesn't matter - no issues. Most modern cars have that combo of aluminum head and iron exhaust manifolds.

I think 220's a little big for a DD, unless you have a 434 SBC - but it's your truck and you can do whatever you want with it. The big volume heads will lack velocity at low RPMs, and will tend to be a little softer on the bottom end (less torque). If it were mine and I was starting from scratch, I'd use a set of AFR 185's and make some huge low end torque with still nice top end HP.

Will the ramshead manifolds even match up with the ports on the 220's? I'd imaging it's like trying to exhale through a straw while running.....

[72peace]

Originally Posted by 406 Q-ship

On a 350.....yeap those heads areWAYtoo big

If your going to run that big of a port in the head, why oh why would you not be installing 2" primary headers if bigger is better. Your combination is going to be way lazy in lower RPM range for torque. Forget the Horsepower numbers and build the engine for torque, that is what really moves the vehicle anyway.

OK, OK I got it. Since I would need to sell these first, what would the 220cc go for and what size should I be going with?

Cheers,

[406 Q-ship]

If it were me I would not necessarily go for even anything as big as 195 on a DD 350 unless there was a pretty stout cam to back it up, and with that much head and cam, headers would be a must to get the most out of them. With stock manifolds, I would go with a set of the Vortec heads and a split duration cam. No matter how good the ramhorns are they are not headers and will be the cork in the bottle. Heck I have a 406 in a 71 Monte Carlo that still runs ported stock 73 Z28 heads (think 165 cc) that pulls like a monster.

[cdowns]

i've used 170cc heads inn both cast iron and aluminium and found them to b a great upgrade on a street motor

as far as ramshorns and aluminium if you use headers t is steel on aluminium too// but my thought is spending dollars on an upgraded head package i like them to flow to thier full potential

[bubba353z]

If you want a set of built up L98 aluminum heads, check out:

http://www.frrax.com/rrforum/index.php?showtopic=15645

Tell him Bubba sent you...