Cam selection for 418 LS3 Stroker?
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
Cam selection for 418 LS3 Stroker?
I am replacing my short block in my 08 with a 418 stroker (Texas Speed motor). The shop asked me about what cam I want in it. I really have no idea. My first thought is to keep the car running smooth, so not go too big...but, if I go with one that isn't large, how much power could I be leaving on the table? The shop talked about a 600 lift cam and told me it would still be smooth and give great power. I'd like to get some feedback on what I might want to get for a cam. Give me your impressions of the feel at idle (is it lopey or smooth?), basic rwhp increase it gave you, etc. Thanks in advance!
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
I am replacing my short block in my 08 with a 418 stroker (Texas Speed motor). The shop asked me about what cam I want in it. I really have no idea. My first thought is to keep the car running smooth, so not go too big...but, if I go with one that isn't large, how much power could I be leaving on the table? The shop talked about a 600 lift cam and told me it would still be smooth and give great power. I'd like to get some feedback on what I might want to get for a cam. Give me your impressions of the feel at idle (is it lopey or smooth?), basic rwhp increase it gave you, etc. Thanks in advance!
The lift is only one parameter. My cam's lift is more than .600 but because of the relatively short duration, drives like stock until you put your foot into it. I am not trying to sell you on my cam. There are better choices for your 418.
There are threads on the forum to help you understand cam spec's and the affect it has on a stroked LX.
Last edited by Mez; Mar 27, 2009 at 05:24 PM.
Safety Car
Joined: Nov 2007
Posts: 4,537
Likes: 1,403
From: Bethesda MD
If you want something tame, just stick a cam that works in the LS3 in it. The extra cubes will mellow it and it will provide a strong bottom end. 228/236 114. You can also take a look at some of the milder LS7 cams to get ideas.
The guys at TSP know the LSx motor very well and can guide you.
The guys at TSP know the LSx motor very well and can guide you.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
I vote the new G6x3... The updated version of my cam. With your bigger engine it is a smaller cam than it is in my car and as you know my car is docile, I drive it daily.
That said I think you would have to flycut for my size cam. Wait, you are getting a new short block so you can specify valve reliefs in the pistons I guess!
Be sure and get the highest compression you can (you'll probably have to mill the heads) as compression tames big cams.
That said I think you would have to flycut for my size cam. Wait, you are getting a new short block so you can specify valve reliefs in the pistons I guess!
Be sure and get the highest compression you can (you'll probably have to mill the heads) as compression tames big cams.
Burning Brakes
Joined: Feb 2006
Posts: 903
Likes: 5
From: Miami FL
alot of things in for consideration. ie: gears, auto or manual, daily driver or not etc. Like someone mentioned before, lift is a very small part of the equation.
I would say go smaller than you would think. I pulled the large cam out of my car which was a 256/260 .630/.645 114lsa cam. It made great power, but made it all at 6500rpms. Very soggy power band down low compared to my 240/244 .599/.603 111lsa cam now. Driveability is the same as with the larger cam due to the lsa but 30-45ft lb of tq under the curve better with same peakish hp.
Dougie
I would say go smaller than you would think. I pulled the large cam out of my car which was a 256/260 .630/.645 114lsa cam. It made great power, but made it all at 6500rpms. Very soggy power band down low compared to my 240/244 .599/.603 111lsa cam now. Driveability is the same as with the larger cam due to the lsa but 30-45ft lb of tq under the curve better with same peakish hp.
Dougie
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
alot of things in for consideration. ie: gears, auto or manual, daily driver or not etc. Like someone mentioned before, lift is a very small part of the equation.
I would say go smaller than you would think. I pulled the large cam out of my car which was a 256/260 .630/.645 114lsa cam. It made great power, but made it all at 6500rpms. Very soggy power band down low compared to my 240/244 .599/.603 111lsa cam now. Driveability is the same as with the larger cam due to the lsa but 30-45ft lb of tq under the curve better with same peakish hp.
Dougie
I would say go smaller than you would think. I pulled the large cam out of my car which was a 256/260 .630/.645 114lsa cam. It made great power, but made it all at 6500rpms. Very soggy power band down low compared to my 240/244 .599/.603 111lsa cam now. Driveability is the same as with the larger cam due to the lsa but 30-45ft lb of tq under the curve better with same peakish hp.
Dougie
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
The short block is built...Texas Speed has one with my name on it...just waiting for HPS to give them the word to ship it. If I go with a custom short block, I am looking at a 5 week build time...don't have the patence for that. Joe, we'll talk out at the track tomorrow.
The car is my DD and also my primary car to race at the strip in our Corvette Challenge in South Florida. I am figuring that with the power I will be putting out, I will have to get a 6 point bar shortly. Other items that I am having installed with the 418 are; torque converter, long tube headers and a line loc for the DRs. Heads and intake will remain stock LS3 components for now. I am replacing the short block due to hydrolocking the motor.
The car is my DD and also my primary car to race at the strip in our Corvette Challenge in South Florida. I am figuring that with the power I will be putting out, I will have to get a 6 point bar shortly. Other items that I am having installed with the 418 are; torque converter, long tube headers and a line loc for the DRs. Heads and intake will remain stock LS3 components for now. I am replacing the short block due to hydrolocking the motor.
Safety Car
Joined: Nov 2007
Posts: 4,537
Likes: 1,403
From: Bethesda MD
Do the pistons have valve reliefs? What CR will you be at?
If you are going with TC and drag race that much, I would go bigger than I originally posted as long as PTV is not an issue. A 2800+ stall reduces the need for bottom end TQ. Something like 232/236 113 or 236/236 113 with a degree or two advance will be streetable on a good tune and get you down the track in the 10s with good tires.
When you say "Heads and intake will remain stock LS3 components for now", I assume that you are switching out the springs. If not you are limiting your lobe selection and the .600 lift cam is out.
If you are going with TC and drag race that much, I would go bigger than I originally posted as long as PTV is not an issue. A 2800+ stall reduces the need for bottom end TQ. Something like 232/236 113 or 236/236 113 with a degree or two advance will be streetable on a good tune and get you down the track in the 10s with good tires.
When you say "Heads and intake will remain stock LS3 components for now", I assume that you are switching out the springs. If not you are limiting your lobe selection and the .600 lift cam is out.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
Yes, springs will be changed on the heads. But, the heads will not be worked beyond that. Gearing is the factory 2.73 (Z51 gears) and my 08 has the A6 transmission. I drag race at least once a month and I do have MT ET Street Radials (305-35-18) that I put on the car before racing. The car is also my DD, so streetability is very important as well.
Tech Contributor
Joined: Mar 2003
Posts: 12,094
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Low end comes from proper compression. Sticking in a cam designed to peak at 6300 in an LS2 will not peak at 6300rpm in a 416 and fights the peaks manifolds are designed for. Quoting (guessing) cam specs for motors you dont know anything about is a waste of money in the end. The intake manifold for example is a determining factor of where it has to peak in rpm. Using too small a cam and 'throwing in a few degrees advace' to raise low end is a band-aid fix and lowers the already too low peak rpm for the displacement.
Let comp determine the peak RPM if you dont have software. Guessing cam specs when you didnt use it in a motor is the biggest waste of time and money I can think of. Guys have been learning lots of disappointment when they try these guess-job cams especially with heads that dont like certain cam specs. Is it a AFR 225? Is it a trick flow head? LS3 heads? FAST manifold? LS3 manifold? Rattling off cam specs as a one size fits all is really wrong here.
Call a shop that built a motor like the one you want and buy their cam. Otherwise I promise you that you will see 480rwhp from a LS3 stroker and shet yourself for listening to guesses.
Let comp determine the peak RPM if you dont have software. Guessing cam specs when you didnt use it in a motor is the biggest waste of time and money I can think of. Guys have been learning lots of disappointment when they try these guess-job cams especially with heads that dont like certain cam specs. Is it a AFR 225? Is it a trick flow head? LS3 heads? FAST manifold? LS3 manifold? Rattling off cam specs as a one size fits all is really wrong here.
Call a shop that built a motor like the one you want and buy their cam. Otherwise I promise you that you will see 480rwhp from a LS3 stroker and shet yourself for listening to guesses.
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
Heads = LS3 factory with necessary springs for additional lift of cam
Intake = LS3 factory
Short Block = Texas Speed 418 LS3 with steel top rings
My shop is figuring out what cam, I am just looking for additional information as to what others have used successfully in this combo.
Intake = LS3 factory
Short Block = Texas Speed 418 LS3 with steel top rings
My shop is figuring out what cam, I am just looking for additional information as to what others have used successfully in this combo.
Melting Slicks
Joined: Jun 2002
Posts: 2,168
Likes: 16
From: Phoenix AZ
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
Heel & Toe
Joined: Oct 2008
Posts: 18
Likes: 0
Le Mans Master
Joined: Aug 1999
Posts: 8,827
Likes: 10
Originally Posted by gtodoug
I would say go smaller than you would think. I pulled the large cam out of my car which was a 256/260 .630/.645 114lsa cam. It made great power, but made it all at 6500rpms. Very soggy power band down low compared to my 240/244 .599/.603 111lsa cam now. Driveability is the same as with the larger cam due to the lsa but 30-45ft lb of tq under the curve better with same peakish hp.
WOW that was a big cam!!!Quikzilver,
Your shop will probably have a great grind for you - but please share it with us so we can share our experiences/epinions with you.
Depending on compression, you can get away with a fairly mild cam and crack the 500 RWHP mark and have a fairly nice torque curve.
Here's a question for you - how do you feel about that big lopey sound of a big nasty cam emanating from your brand new C6?
I didn't think I would like it on my nitrous C6Z, boy was I wrong! I loved the visceral nasty sounds, vibrations and sensations my big bump stick evoked. It was really a head turner, too. Do you care one way or the other about the sound/car shaking?
Thread Starter
Le Mans Master
Joined: May 2003
Posts: 5,362
Likes: 3
From: Delray Beach FL
I want the cam to be sort of tame (looking at a 114 LSA), since it is my daily driver in addition to my drag car. I think the shop was looking at one of LG's cams...G6XE or something like that. I will find out this week from the shop and let everyone know. I should have dyno information in the next week or two, once the motor is complete and broken in.
Intermediate
Joined: May 2009
Posts: 35
Likes: 0
Recently paid a visit to the local speed shop in my area called G-FORCE and they had a ls2 vette making 386 at the wheels with a full exhaust varam intake and tune, they installed a comps cam and dynoed the car again and it made 451 rwhp & 401 ftq, Needless to say I ordered mine the next day. The specs were 238in / 242ex at .50 and 610in & 604ex with a 115 LSA. 65hp gain at the wheels.