Gotta cam profile to work from?

 

not yet, trying to figure out if my goal of 7500 shifts is gona fit in my budget. If it means shaft mounts and a bunch of head work like the post below yours Ill have to lower it some

Plan on hopefully just gettin a set of l92s from an ls3 so I get the hollow valves. Just kind of worried since Ive read horror stories of turning rpms with these motors due to the narrow diameter springs and their limits. Basically want to run right up to the limit of these problems and not go broke. Ill have to look into modded stock rockers didnt know that was being done thank you

 

There's not a bunch of room to cut the pockets deeper or wider on these heads. I wound up using the best PAC spring available for the stock pocket and called it a day. Once you start adding up a bunch of machine work costs, the "budget" aspect of these heads goes out the window.
My setup with a hyd roller will be shifted at 6,500 or so, but I'm using heavy solid valves.
If you are thinking of spinning it up, hollow valves are a good move.
The stock rockers are super light over the nose, and most aftermarket rockers will likely float much sooner.
Get a cam without super aggressive ramps, along with Harland Sharp modded stock rockers, light valves, morel lifters, and premium springs and you might have a winner.

Good luck with it.

 

Ok - I'll be the one to ask....

Why do you need to go to 7800 RPM?

 

7800 out the back. 4.56s goals of bottom bottom 10s pumpgas lq4 combo in a 2700 lb mustang

 

I guess the real question should be is "who is spinning there lq4/l92 stuff higher than 7500 rpm and what did you do valve train wise to get there"

You dont need to run over 6250 either...so ..........................

You dont need to have l92s so keep 317's

You dont need another cam keep stock...

 

I guess the real question should be is "who is spinning there lq4/l92 stuff higher than 7500 rpm and what did you do valve train wise to get there"

You dont need to run over 6250 either...so ..........................

You dont need to have l92s so keep 317's

You dont need another cam keep stock...

Not hard....

Stock OEM rockers, stock lifters, LS3 valves.... that's what I would start with. Honestly the stock bottom end of a 6.0L truck with rod bolts in it wouldn't scare me either.... hell if you had a LS2/LQ9 and wanted to tweak the top end I'd push over 8,000rpm and not really pucker my asshole too much.

Cam, springs and pushrods with someone who can check and install them correctly and you are good to go.

Doing this with a FAST is a PITA, a single plane or maybe that new Holley deal would be my choice....

I wouldn't be scared of the RPM you are talking about with any part of the OEM LS stuff, oil system, rods, crank or whatever....

Bret

PS I have a couple of brothers in PA and a few of their buddies who I have done valvetrains like this for, all with cathedral heads but figuring the math for the mass of the LS3 valves is almost identical.

 

thank you for rewording it good sir

 

I'm using solid stainless valves, Comp 921 springs shimmed a little, HUC lobes, Comp upgraded trunion stock rockers, and I shift at 7100-7300. Enough to make my 4000lb beast go 11.50 in 4200ft DA. My heads are 317's and only flow 305cfm. My compression is also set up for future boost at only 10.3:1. That run was when the motor only had a few hundred miles on it and I haven't made it back to the track yet. 17" drag radial also.

 

Just go with what Ed says. He did the head cam and intake work on this and it works great.

Tim

 

lol perfect person to come into thread. Are your heads cut or diff valves? Or just running a reg diameter lsx style spring? Which rockers are you running?

 

LS3 valves a must. Ferrera exh valves another must. Lunati Dual spring kit. stock rockers with a trunion upgrade.
Manton 11/32 pushrods
Ed cam

reved it 7500 when I could not see the shift light on 1 pass

Tim

 

so what Im getting from this... for 7500ish I should be fine with

ls3 hollow stem valves
good pac springs
harland sharp modified stock rockers
cam set up to not have extremely aggressive lobe/ramp rates

should be able to handle 7-7500 shifts and hopefully not implode

if I could reach my goal with 7200ish shifts then by all means I will, but rpm is powa

 

OK - first of all - RPM means "Ruins People's Motors".

No sense to running an engine into the stratosphere if it doesn't make power there.

If you want something to perform similar to Tim's project, let me know, I can do this for you. Otherwise, I think you're just going to drain your wallet for the sake of a high shift point....

 

Ed drove the car this week goes down the highway like a dream. Working on little tune up things today to make it idle a little better.
Took the girls for a ride last night all they wanted to do was wheelies. LOL

Go with what Ed tells you he has done 4 engine combos for me over the years and have done exactly what I asked for and 1 was .70 faster that what I wanted.

Eds theory K.I.S.S.

Tim

 

I have been very happy with the lunati spring kit for around $225 it is doing the job on my motor and dads daily driver.

PAC stuff is very nice used it on prior projects but is deff higher end springs that may not be needed. I know Ed buys/sells alot of lunati kits.

Tim

 

First of all i would NEVER tell anyone to build a low rpm motor when they are attempting to make power and go fast. At a 7500rpm shift point and 7800rpm trap rpm, you need to start questioning the stock style oiling system before camshafts and valvetrain knowing their inherent failure above 75ish.

 

with 2700lb it is not going to take that much.

I am waisting a much of power right now trying to get things figured out. I picked up 4 mph in the 1/8 and .10 but only 2mph 1/4 and .30

I don't see a reason why you would need much over 6500. best thing you can do is get the rest of the car to work really well and use the power you have.

Tim

 

http://ls1tech.com/forums/14985321-post7.html


search his name, he did real well with this setup and his current one

 

goals anything under a 10.3, if that means I can get there by shifting at 7000 then I would love to do that and have the car be a lil less prone to grenading. Hard to find many builds of this nature to be honest, everyone seems happy with a high 10 in their swapped lsx cars

 

my dream setup 346 ls1 with mast smallbore ls3 heads carbed and pull it to 8000

 

if I had more money or was willing to have my car down for a long time Id be shooting for 8k, but thats no fun for me. Just want my cheap low 10

 

Facts? Show me a factual statement in your post..............

You said RPM means "Ruins People's Motors".......... you cant take that back ...

Woooo woooo ed he can obtain his goals at 7200 rpm ....but rpm runs peoples motors...

"Nothing dealing with stock GM L92 heads can be considered "high end" pieces."

Whats considered high end?

I think "budget" should never be used when building motors...seems like an excuse to cheap out.

Good luck to the op's build ...........

 

7200 would be fine with me... would feel comfortable running a set of modified stock rockers as well. Mustank if you want to give sponsor me I will let you gorgeous

 

na this is through a carbed setup with a vic jr, and thanks for the post