Would I see any gains with the LT4 intake but not other mods?
What about if I added headers? would i see much gain over just headers?

 

Won't fit LT-1 heads without SERIOUS mod's.

 

hmm ok, good to know


so what would LT4 heads and intake yield me without anything else?
and how much more with headers?

 

If you go with LT4 heads and intake without a matched cam you would most likely be wasting your time. Headers on the other hand would be a wise move even on a stock cam.

 

Alone upgradiding to an LT-4 package is a waste of time..

Now if you want to slap that LT-4 intake on a set of AFR 210's... now that my friend is a different story.

 

Everyone bangs the drum of "LT4 parts aren't worth the money" crap. They are, if you want equipment that is already matched to each other, and was used on thousands of factory vehicles and is proven reliable. The LT4 intake, heads, and cam are perfect for each other and make good good power.

The next big thing, if you are looking for BIG power, p&p LT4 heads will make more power than p&p LT1 heads.

If you just want a reliable power upgrade, I say get the LT4 package from GM, Heads, intake, cam, along with header and exhause and you'd be plenty powerful.

 

the thing is I just dont want to go as far as the cam at this time, the intake is coming off for a gasket replacement, so I figured a couple more bolts and I would have the heads off.

Maybe I'll just add 1.6 rr's or something.

 

my view is if you are going to do it, you might as well do it right the first time. Granted I am not saying that just because you are taking the heads off that you should go for that 383 you have been planning, but financially it makes more sense that if you are going to take your heads off and put on LT4 heads you should probably just do it once and swap the cam out now instead of spending $700 to have some one do it now and leave the stock cam, and then spend another $700 next year to slip that cam in. Believe me, next year when you are spending that second $700 you will be wishing you did it today.

 

If thousands of cars left the factory with these "matched" parts tell me what cars had the HOT cam stock? The LT4 HOT package is for those unwilling to do research. The LT4 intake does not fit the LT4 heads well especially for such perfectly "matched" pieces, and ported LT1 heads will flow more than as cast LT4s and do so for less money and with smaller ports for better velocity.
The stock engines cork is the cam not the heads, the stock heads flow better than a lot of Gen1 aftermarket heads . 1.6 rockers and better springs can help some but 1.6 rockers are not always the best thing to do, better to consider future plans and wether they include a cam and buy a set of rocker that will work with that cam might be 1.6s might not. Headers are always a good mod and engine will work best when the incoming air and outgoing exhaust are free flowing. One of the Impala guys ran the math and one psi in the exhaust system soaks up something like 12ft.lbs. of torque, and that ignores the fact that pressure pulses in the headers can actually help suck exhaust out of cylinders further reducing pumping losses in the engine.

The LT4 heads can be good IF you need something more than ported LT1s can provide which means a real screamer of a a 350 spending a good amount of time north of 6000rpms or a stroker you plan to rev past 6000rpms or so. The intake simply has more material so YOU can make the ports match the heads, as several guys here have posted till their fingers were bloody numbs the stock LT4 intake DOES NOT math the heads well at all, there is just material there so you can port it too.

 

Well I will do the installs.
I dont want to do a cam right now, bottom line, stock cam will remain.
I'm not looking for a 900hp beast, I jsut want a bit more very reliable power that wont kill my milage, and wont be so much that other parts will need replacing, ie rear end.

And since my head will be coming off I figure the easiest power to add at this point would be in the heads intake tb area.


But it sounds like the LT4 stuff isnt that great. so maybe I will just put it back on the way it came off and get some coated headers.

 

go get some afr heads!!!!

 

Bigger heads on a stock cam is backwards, the cam can not adequately support the larger runners. There was a time when heads were the first major engine part to change for power but that was BEFORE the time of the LT1.

 

It sounds like you don't have many mods. I'd go with bolt ons, then when you decide you want more power do a head/cam package.

- Z28WannaB

 

Stock down to the factory paper air filter.

I do NOT want to do a cam, but when the intake is off replacing the heads or whatever is pretty easy, or well easier. Even something like 1.6 rr's or something, I dont know, I have the 3" SLP TOTL and the SS airbox.
I put down 271 and 305 to the wheels as it sits right now.

I would like 300 and 315 ish, jsut enough quicker that I can notice it, but not so much that I take reliability, milage or too much for other parts like the clutch and rear.