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H.O. heads on my stock, renix block

The hassles start with having to change the intake, which drives changing the throttle body, which brings up the problem of adapting your old throttle position sensor and wiring the Idle Air Control. I don't know if the injector rail will swap and if the vacuum ports are the same. All in all, it would mean a bit of work. Personally I don't think the gains would be worth it, but that's personal preference. The biggest difference in power from the Renix and the HO lies in the cam, computer, throttle body. The head does flow a bit better but for crawling, that will actually hurt your bottom end while helping the higher revs (highway).

Maybe others can chime in, but I have driven both and really don't feel that much difference between equally maintained motors.
 
The HO head does flow significantly better than the Renix head but I don't think it's worth swapping the HO head onto your Renix block. Apart from the reasons that Tom mentioned, you can port the Renix head and the result from a well-ported Renix head will be nearly as good as a ported HO head. If you want more from your head, read my head porting article and if you feel confident enough to DIY port your head, invest in a Standard Abrasives deluxe porting kit and follow their instructions to the letter.
If you get it right, you'll gain torque at higher rpm without losing any at lower rpm.
 
FWIW I am running an H.O. head on my renix machine, I ported the head and am currently running the original renix intake on the H.O. head, the ports don't match up well, but its close enough for use untill you can afford the time/money to swap over to the H.O. intake/throttlebody (I am waiting to get my hands on a 2000+ intake) I have almost 1000 miles on my set up now and it has worked flawlessly, as a matter of fact I have notice NO noticable power loss using the mismatched head/intake setup, and have been getting better mileage to boot!, can't wait to swap in the rest of the H.O. stuff, should have a noticable gain in power then.

Josh
 
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