Guest Badzx Posted May 2, 2003 Share Posted May 2, 2003 What other mods can be done before the swap? I've all ready going to port match intake/exhaust, polish valves, port turbo exhaust housing . Intercooler not in budget yet, so any low cost mods info would be great!!! Quote Link to comment Share on other sites More sharing options...
Mudge Posted May 2, 2003 Share Posted May 2, 2003 Port match to what? The exaust is never port matched to anything, what extra lip is there on the exaust side is there for anti reversion. The intake runner should not be an obstriction to the intake manifold which it will be if you open it up, moreover the intake runner itself is not the low flowing part of the head. In other words, dont touch it. Work the bowls if you want to port it, polish the exaust runner for heat retention but do not do the same to the intake side. Quote Link to comment Share on other sites More sharing options...
Guest Badzx Posted May 2, 2003 Share Posted May 2, 2003 To the head, so the 1/4 in lip on the exhaust manifold compare to the exhaust port on head is ok, wouldn't that create excessive back-pressure on the exhaust side? Would it not be good to remove any remaining casting from the intake manifold and intake port and match the two for continuious flow into the combustion camber? I want to prepare the head for furture Upgrades !!! Thanks for info Quote Link to comment Share on other sites More sharing options...
Mudge Posted May 2, 2003 Share Posted May 2, 2003 Casting flash can be removed yes. If the exaust manifold is BLOCKING the exaust port then you have a problem, if the head chamber is smaller than the exaust manifold/header then that is NORMAL and desired. The problem with exaust is you cannot just blindly open it up at the port. If you haven't read any books on head porting, it would be strongly advised, alot of people screw up thier own heads by not knowing what they are doing, killing low end power and either making no more up top, or even hurting it. Even some pro shops dont seem to know what they are doing, example would be a "Stage II" head with a cam known to make 375 RWHP on a stock head car, and these "awesome" heads only make 25RWHP more, which tells me they are lying about flow numbers, and its not uncommon to cheat the flow bench or flat out lie. For doing a real job on those heads, expect 30-80 hours of labor. As for continuous flow on the intake side, usually a porter will leave a 1mm step or so for "safety" and for gasket to seal beter. If you have good strong gasket marks on your intake and your head, scribe them before they dissapear. If the heads intake runner is smaller than the intake manifold outlet, thats when it will not be able to put as much volume into the head as it should be able. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted May 2, 2003 Share Posted May 2, 2003 I would port match the intake ports on the head and intake to the gasket, and make sure there isn't a lip there. That should eliminate turbulence. You can do the same thing with the exhaust. I would not do any port work in the bowls without having the head flow tested. That is not a job for a shadetree mechanic, and you can often do more harm then good. That is why good port work is expensive. Good luck. Quote Link to comment Share on other sites More sharing options...
Guest Badzx Posted May 3, 2003 Share Posted May 3, 2003 i've been arround the preverbal block a couple of times, I'm not planing to do anything to bowls just match up the intake and exhaust port. I'll save that for the next stage off the game and more time. Thanks for Info and Input Quote Link to comment Share on other sites More sharing options...
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