It just depends on where your gonna be happy with the performance when it comes down to it. If you want to do it once and be done with it and be happy with the hp number yeah I see your point. And that is what I had intentions of doing. But I caught the bug.....and wish I would have did a couple of things different. So my point is if you plan on adding power later.......do it right the first time cause it will save yeah money later on when you have to buy another set of head if that is what it is that needs to be upgraded.

I didnt just go by dyno numbers.....I built my motor got it tuned and dynoed it. And that is the hp I ended up with. I have a daily street driven 450 NA motor that I get 24 mpg out on the interstate. And a whole lot more power when blown. Took the procharger off cause I was only gettin 4 psi out it........ going twin turbo now.

 

What's your rwtq???

 

It was 365 @ 5200...I posted the numbers years ago when we put the new Joe Overton spec'd "small and nasty grind" (Joe's words) cam and installed the LPE heads that were re-ported by Eric Bradby and lots told me that the numbers sucked and the car wouldn't run for crap. The actual curves were very flat with huge "area under the curve" that's always talked about. Either way the car weighed 3650 lbs with me in it and ran the numbers in my sig. The new owner pulled some weight, re-stalled the Vig 4000 to 4400, added M/T 325/50 DRs and has been 11.20 at 122ish...60's are now 1.48. He'll get it in the 10s on motor probably with a little more weight reduction.

I have never liked dyno numbers and rarely give them any weight. Dynos are great for tuning, even though I like tuning on the street better for drivability. I've beaten and out mph'd cars with 450rwhp dyno sheets and have seen countless dynos provide generous numbers for the sake of bragging rights. The truth happens when the lights on the tree drop.

--Alan

 

but but but big dyno number make them go faster.

 

pshhhh i knows that im edumicated....peak power make car go fasttttttttttt........

 

With $1500 it is easyly doable, i just picked up a set of lingenfelter cnc ported heads that flow 280 on the intake for just $1300 shipped.. and they came with rockers, pushrods and new lifters. Not to mention they were already topped with ccc dual valve springs, arp rocker studs and guideplates... just lurk around sites like this and wait for a deal to pop up.

 

^This is very true....may even get some decent heads even cheaper if you are willing to look for head porters other than LE or Ai which is all anyone talks about anymore here as far a ported stock heads go. I picked up my Combination Motorsports Stage 2 CNC ported heads, (2.00" intake, 1.6" exhaust valves) that also flow 280ish intake for only $750 shipped I found on racingjunk.com. They were a popular LT shop with good ported heads back in the early days but went out of business unfortunately in the early 2000's. There are deals to be found if you look hard enough here, craigslist, ebay, racingjunk, ect...

 

I gained power on the dyno and went slower or the same on 2 different occasions. One was with a cam swap, the other was with a head swap.

 

Lingenfelter heads seem to work well. Far as I know Combination Motorsports farmed out the head work and while it was good "for it's day" our standards of performance were a lot lower back then. Back when Combination Motorsports was a big deal the fastest heads/cam/spray Impala was 11.6 at 117mph now I understand spray cars are not helped as much by DA but that was -700ft. My car runs 11.5 at 115-116 at +500ft naturally aspirated.

Not that the CM stuff isn't good, but I would not compare it to what is available today.


I wanted to say more about the vast "superiority" of aftermarket heads and all the excuses used to push them.
Who has measured stock deck thickness and found it to be inadequate?
Who is routinely lifting them because the "decks are too thin"?

Maybe I would propose a 3/4" deck hinders cooling by putting too much metal between the coolant and what it needs to cool? I can't support that statement but then again the vast superiority of a 3/4" deck for a mild NA build can't be supported either so we are even.

There are SSSSSOOOOOOOOOOOO many things people swear they need to upgrade without ever stopping to THINK about how many "failures" of the stock equivalent they have seen. Like timing chains. I have seen more reports of broken "upgraded" chains than stock despite the fact there are many times more stock ones out there with far more miles. Stocker is not perfect, it is known to be a little sloppy and sure a roller could free up a HP or two but it seems everyone believes it to be weak, hell a $20 crank sprocket will tighten it, and the waterpump is another item blindly replaced with something non-stock which if you are going to put a lower flowing piece on that is no longer timing set driven you just took 10+hp load off the stock timing chain making it even less likely to pose a problem. People don't THINK!!!! They read magazine, buy those parts and THEN come up with excuses for why their stuff is better than stock despite costing more and NOT performing any better.

The guy I mentioned I had bought my core heads off of made excuses about why he was happy with the TPIS ported AFRs after the POS 383 he had built by a TPIS employee pushed sleeve and badly overheated. He was happy the AFRs took the punishment and was sure the stockers would have warped. If he had bought good parts from a good company in the first place he would not have pushed a sleeve and overheated and would have saved a small fortune.

 

Mike I agree Dyno racing is for *****'s.

 

Nitrous hits the intake at minus 120 degrees. It's negative DA in a bottle. Maybe if they weren't hitting it out of the hole the DA would have helped them.

There are more reasons to run an aftermarket head than the deck thickness. That might be one of the more common arguments, but there are many other reasons. Port size, port shape, cnc'ing consistency, valve size, quality control, etc.

Hinders cooling? You may propose that, but you have no data to back that up. My new motor with AFR heads runs very cool. My old 350 with TFS heads ran about the same as the 350 did with stock heads. Maybe my AFR heads have better cooling passages, who knows. There are too many variables. My big motor runs around 10-15 degrees cooler with zero change in the tune regarding fan turn on temp and with the same thermostat.

For me personally, the timing chain is a dirt cheap maintenance type of part. If I was rebuilding an engine and was going to upgrade the valvetrain with stiffer springs, a new chain would be in there guaranteed. An electric water pump allows the use of an sbc chain which opens up the availability immensely. You can buy a really good double roller chain for around $50-$60. A new stock replacement setup costs substantially more.

 

i didnt read the whole thread but ur talking about too much power for a cast stroker crank. but thats.me.. id be scared. i have some afrs and an intake with matched cam that put down 450+ if u want to buy it all lol

 

I'm using ported stock head on my forged 383....597 rwhp with a T-Trim