NEEDforSPEED

subject says it all

NEEDforSPEED

also would gen 1 350 headers work on the lt1 heads?

TexasLT1

yes, any 3rd gen header will work. max lift with stock springs is about .490 or something around there. LT4's are good to .525.

NEEDforSPEED

all you need to do would be to get some diffrent springs right? that can handle passed .525

TexasLT1

yup, depends on the springs. what cam are you planning on running?

NEEDforSPEED

i have not decided, but i can give you a list of some of the parts im running to hopefully pick the best cam, i was going to run "083 castings" but i plan on selling them and putting the money tords the modded LT1 heads, i was looking at a lot of different roller cams but im not that good when it comes to the best cam for my combo...

So heres what i have or will be getting soon as the engine build up gets going....

Fresh 2000 5.7 vortec, 2-bolt main - stock everything,
LT1 intake, port match to the heads,
No EGR, either 24lb or 28lb injectors,
LT1 heads , Gasket matched, bowl work, mildly ported and exhaust fully polished, what comp ratio should i go with
When i look into head gaskets?
shorty headers, 3" piping, y-pipe - back, no A.I.R or emissions, probably run no cat either,
a really good better then stock ram air with a good breathing airfilter,
Rebuilt 700r4 with shift kit, witch stall?
Aluminum drive shaft, 3.27, limited slip poise

i have no clue what to see for rear wheel HP and TQ with this setup....

ShiftyCapone

iTrader: (7)

You plan on modding the coolant passages in those heads to make them work. You may want to read up on that. The heads are great but the conversion to non reverse cooling is extensive. Sometimes it becomes not practical.

NEEDforSPEED

seems perrty practical to me, to have more lift then the 083 casting, so i can run a bigger cam, have more flow make more power, + im sheading the LBS up front...

mw66nova

iTrader: (13)

what all is involved in the conversion?

ShiftyCapone

iTrader: (7)

There are other heads that will do the same thing that don't require a very unique conversion.

As to what is involved, I am not sure. You have to weld the coolant passages shut and do some other stuff. A search on the matter will bring up the info that I cannot remember.

NEEDforSPEED

i have reseached it thorly, cheap and E-Z in my case
and thats what im doing becuz i want to... now some one help me pick a cam

TexasLT1

depends largely on what kind of power you want, are you going to port the heads, and what can you tolerate in a street car?

NEEDforSPEED

i want a solid 325 or more to the rear wheels, the limitations lie within the engine and tranny, witch wont live to see past another day over 480hp or so, if i do push them up to that point, im not sure about the rear end what it can take as in terms of what HP or TQ it can handle being stock...
the setup has a tpi computer with mass, so that also well be a limitation as to what the computer can handle, or how hard it will be to tune, i want the power but i want decent MPG too,
but well take the power over mpg if need be

TexasLT1

here's your recipe:

LT1 – LE1Head/cam package will pull from 2,000 to 6,200 RPM and should make *370 – 390 RWHP with 30 lb. injectors, 52 MM T.B., 1 ¾ LT’s no cats, good tuning, etc. This will have an idle similar to the HotCam, CC 305, etc. but will make more HP & TQ than these cams with the same RPM range.

The LE1 heads consist of:

Stock Valves with Back Out
CM 612 Spring Retainers & Locks
195 CC Intake Port
Milling
Cleaning
Assembly
Flow About 255/180
Ready To Bolt On
*The HP#’s mentioned are typical for an F-body with 6 speed, stock rear and with ALL of the complimenting parts mentioned.


$1100 for Heads/Cam package and get 425+ at the crank



Contact Lloyd Elliot at NightTrain66@msn.com , he does great work and is very well respected on CamaroZ28.com.


If you don't want to go the ported head route, use stock heads and run a CC306 and put down about 325-340 at the wheels or more.

NEEDforSPEED

This is kind of interesting to me, i saw that ported lt1 heads everything else stock will out flow stock lt4 heads, by almost a huge margarine, the test was done on a flow bench, iv been looking left and right for that article, at the time i saw it it wasn't important to me till i just thot about it now, but if you look at the cut away it doesn't seem logical too me



Shown below is a cross section comparison of the LT1 (photo A) and the LT4 (photo B) heads. The LT4 Intake port is 25cc larger than the LT1. The revised rocker cover rail is due to the taller intake port opening. Intake valve sizes are 1.94" on the LT1 and 2.00" on the LT4.



In the photo below, note the differences in the exhaust ports on the LT1 (photo A) and the LT4 (photo B). The short side-radius offer much smoother flow and the throat cut is slightly different. Exhaust valve sizes are 1.50" (38.1mm) on the LT1 and 1.55" (39.4mm) on the LT4. Also notice the LT4's 7/16" top thread on studs vs. the 3/8" on the LT1.

TexasLT1

I'm not sure what you're getting at. Everyone knows the LT4's flow better than stock LT1's, and that mildly ported LT1s will flow about the same or slightly better than LT4's. However, if you were to do an equal amount of work to a set of LT1's and LT4's, the most you could get out of the LT1's is about 275, while you can get very close to 300 cfm out of LT4's.

NEEDforSPEED

I'm not sure what you're getting at. Everyone knows the LT4's flow better than stock LT1's,

thats what im getting at, some magazine, had a flow test done on what i just said above, but they pulled way more cfm out of the ported lt1s vs the lt4s... and all that was done was your basic port job and that's it, they blew the lt4 heads away by a HUGH margarine, look at the cut away above, this is what doesn't seem logical too me,

TexasLT1

yeah, the LT4's were stock. go port them, and you'll blow away the LT1's.

NEEDforSPEED

Ya, but then what if i put 2.00 and 1.56 valves in,
theres donset seem to be much alum left on thos stcok lt4 heads

lol

TexasLT1

there's enough to get almost 300 cfm out of them But basically, you can't go wrong with ported LT1's. You're just going to put down a little more power with ported LT4's is all I'm saying.

NEEDforSPEED

Anyways, as long i get my 325 or more to the rear, im fine....
thanks for your help man, i appreciate it....

TexasLT1

no problem. I'll just say one more thing, you can easily get 325 at the wheels with just a cam, headers, 52mm TB, and gears. With an LT4 conversion, I put down 318 on a Mustang dyno = about 350+ on a Dynojet, and thats with stock LT4 heads, intake, Hotcam. Running stock LT1's with a bigger cam would get the same result. Good luck with your build though no matter what you choose.