Demon355

iTrader: (1)

How much power does this make? How much do you think it's worth in working condition? I can get one just want to make sure the price is right. I don't know what it's out of yet but I know it's an F-Body so I guess it doesn't matter.

nelapse

iTrader: (17)

If I am not mistaken, 315-330 ish HP... if you get an LT1 and use summits lt4 converstion with the heads cam and manifolds you get around 425 fwhp

Demon355

iTrader: (1)

Well I already have an LT1 intake and hotcam so I would just need the heads then. Ah well, just curious to what this motor will produce. Like I said, it's a stock LT4 motor...

nelapse

iTrader: (17)

Just get the heads... You will out do a stock lt4 anyways. If you are doing it to say you have an LT4 when you put the heads on you have one anyways lol... besides, you do not know how the previous owner treated this motor and you know how yours was treated.

urbanhunter44

iTrader: (3)

A stock Fbody LT4 (an extremely rare motor - more likely it came from a corvette) will make an honest 340-350 fwhp. They were rated at 330 but it was underrated. That's totally stock, with stock crappy manifolds and exhaust.

The differences in the motors are:

- 4 bolt main
- Different heads with high rise ports (flow slightly better than stock LT1s)
- Different intake to match the high rise ports (same flow, just different design), and it has NO EGR (this was true on the corvettes, I'm *pretty sure* the Fbody is the same way).
- Intake is painted red
- Bigger camshaft, which allowed for there to be no EGR valve

There are a few other minor things, but I forget what exactly.

The LT4 conversion kit is bogus. You won't make 425 fwhp. On an otherwise stock LT4, the hotcam is good to around 355 RWHP with full bolt ons and a tune. And, interesting side note - GM no longer makes the LT4 intake manifold.

The heads aren't really worth it, since you'd need the intake too. Stock LT1s flow around 220, LT4s flow around 230. It's not much difference. Send some stock LT1 heads to Lloyd Elliot and he'll port them to flow around 275 CFM with his LE3 port job. Or his $1200 LE1 heads/cam package will give you an honest 375 RWHP with the mentioned bolt-ons and tune.

Bottom line: LT4s typically have a premium price tag, and aren't worth it. A decent running LT1 pull out motor will sell for $1500 tops. An LT4 in the same condition will sell for $3k+.

Demon355

iTrader: (1)

Yeah thats what I was thinking. I was waiting for you to chime in Urban

I have an LT1 intake (painted red) but it has already been ported. Enough that I've had "big mouth" gaskets put up against it and the gaskets are smaller then the ports so that makes me happy. Whenever I buy new heads I'll get them machined out to match the intake. I'll be running 1.6 rockers so the hotcam would be what, .535 or was it .525? I'll be using that cam as I can get it real cheap. I don't need a powerhouse of a motor. 12's N/A and low 12's/high 11's on nitrous is more than enough. Thanks for the input guys. Appreciate it.

urbanhunter44

iTrader: (3)

I think it's .535 with 1.6s, but I may be wrong.

With ported heads and the hotcam you'll definetly hit 12s. My car is about to hit 12s and it just has minor bolt-ons.

Heads can usually be had pretty cheap (I bought a spare set for $200 dollars locally), if you look around. Try checking the classifieds on fbody.com, ls1tech.com and camaroz28.com. You'll find a good cheap set.

Good luck, feel free to pm me if you've got any LT1 questions i could help with

Demon355

iTrader: (1)

Would aluminum L98 heads be worth my money? They have small valves though...

My buddy has the Dart Iron Eagle 180's and I'm pretty sure his motor will hit high to mid 12's with his setup. HSR 355 with the Darts, .5xx cam etc. I don't want the Darts though. I was going for the Edelbrock Performers as they make the same lift on the exhaust side as the Dart 180's, but are bigger on the intake side. If I could get the a/L98 heads for cheap, do some blending and put some bigger valves in, I'm thinking that would be cheaper than buying new heads correct?

urbanhunter44

iTrader: (3)

If you can get them cheap enough, and you know how to port yourself. You can actually make them into pretty decent heads once the valves are enlarged.

Yeah probably. Figure you buy the heads for $200 bucks, port them yourself, and have the machine work done for another $300... you can have a nice set of heads. The best set for $500 comparatively would be a set of fully assembled Vortecs from Summit, but they'd weigh more and flow less.

Demon355

iTrader: (1)

Well I can get these vette heads for $450 but they are all rebuilt heads that we're ready to go on a motor but for some reason never used it. I'd just port them out slightly to match my LT1 intake. After that, I don't know what I'd do but this is for next year as I have a set of 081s already in the shop.

Would the vette heads be better then the ported 081? They have stock valves but the bowls have been slightly blended and the ports have been ported out to match the port job done on the TPI base. (081)

urbanhunter44

iTrader: (3)

I'd say the vette heads would be better, if only for the fact they weigh less than half of the iron heads.

zz4monte

Urbanhunter 44 is right they were way underated!!!!!!!Those LT-4 heads were pretty nasty. I saw a crate LT-4 with a carb(back when you could get them from GM high performance) throw down 365hp at the crank.I don't know if this is because the carb. mod. or just that they are that underated?

Demon355

iTrader: (1)

Well, what would you do...the Edelbrock Performers or the Vette Heads? Like I said, not much porting involved to match the LT1's ports so that's all that would be done to them. I've seen people's combos with these heads put some serious power out there.

I know I can do good with the E-Heads but I'd have to port them as well and they do come with bigger valves just cost alot more money. I'd spend near half of what I'd pay for the E-heads on the vette ones and get the numbers I want still right?

zz4monte

Vette heads.You should get some decent flow numbers.What do the edelbrocks run $950-$1050.At that point I would just get AFRs.Vette heads sound like the best for the buck.

Demon355

iTrader: (1)

Yeah thats what I'm thinking money wise. I'm better off with the vette heads...

The E-Heads are $800/head at my buddies price. He works for Performance Improvements. So right off, the Vette heads would be ideal. They have hardened guide plates installed, polished up a bit and ARP bolts. No porting has been done. Talked to the owner the other night about them. I just picked up a TransGo shift kit and Energy trans and torque arm bushings off him, good guy. I have Compcam 981 springs to install, along with my 1.6 rockers. Would I have to replace the retainers and such? I'll be using an LT4 Hotcam. Man, I wish I could use these heads right now...lol!

mw66nova

iTrader: (13)

i like the vette heads. if you can justify it, pop those valves out and do a bowl blend on them. i'm still using the stock 1.94 valves and my combo with 55 more cubes went 12.16@110mph...