Is it worth it to get ported LT4 heads with a hot cam or just port LT1 heads

 

It is not so much porting and polishing of the heads that give you a lot of horsepower, it is the size of the valves. I am not saying porting and polishing without changing the valves won't help, you just won't see huge gains. The valve size is the main reason the LT4 heads are so much better than the LT1 heads. If you have the money, get the LT4 heads and get them ported and polished. If you want to be cheap, port and polish the LT1 heads, put some bigger valves on, and you will still see some nice gains. Ported LT4 heads are the real deal though, check out this one.
http://www.chevyhiperformance.com/techarticles/4496/

 

bang for the buck isn't tehre, but that doesn't mean gains aren't there.

something as mild as the hotcam doesn't require LT4 castings -

Not when you can port the **** out of the LT1 castings for half the price and get all the air you really need in there

 

You don't have the potential to make THAT much power with that cam, so why spend that kind of $ on LT4's? A decent LT1 job with nice midlift & 25X ish peak cfm would be plenty IMO.

The gains are not from valve sizes.. and if you want to do yourself a favor, stop reading magazines. That and "that one" isn't anything impressive. Of course that may be an indicator of why people that know what they're doing despise one of those wannabe's ;)

The ennarnet, she's a dangerous thing ;)

 

[QUOTE]Originally posted by Camaro_Maniac63
[B]It is not so much porting and polishing of the heads that give you a lot of horsepower, it is the size of the valves.

Ummm... No. Do yourself a favor and listen to SkarodoM.

 

I will admit to not knowing a lot about engines, here is the way I see it. You port the crap out of the heads, but you keep the stock 1.94/1.50" valves lets say, where is all that extra air that you are getting going to go if you don't get bigger valves? There is going to be no opening for them to flow in through. Like I said, I am no expert on engines, so please correct me if I am wrong and explain to me how it works. Don't be too harsh on me either Thanks.

 

from what ive read........

extra power is gained when the air that flows through those valves flows at a higher velocity than before, thanks to porting.

also, the stock castings dont flow enough to max out the stock size valves, so those are the two reasons porting will have a benefit.

phil will be able to clarify/correct me, but i think thats the basic idea.

 

so basically porting the LT1 heads a lot will give bigger gains than replacing them with the LT4 heads? just like clarifications

 

Only if it is done properly. We port-matched our LT1 heads ourselves, took it to a dyno yesterday, and looks like we gained nothing, if not lost power. You don't want the same thing happening to you.

 

the LT4 conversion kit is starting to sound a lot better now. 380rwhp and some mods could achieve 410hp pretty easily. Open up the throttle body or put an air foil would increase to 420. im looking at naturally aspired but i dont want to get shafted like camaro_maniac. if i went crazy and installed a turbo next summer who knows what dyno's we would be looking at.

 

well you simply did a bad job if you lost power

 

are these your heads?

phil just posted this in another thread...
that could explain a lot.. no wait, everything

 

Mine look just slightly better than that