Cam question
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Joined: Oct 2019
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From: Cape May, NJ
Cam question
OK guys looking for a little advice. I had a short block built by Thompson motorsports and I asked them to put a mild cam in there something that was had very good street manners but still produced a decent amount of additional horsepower. Here are the cam specs that they put in
Rocker ratio 1.7Intake lift .629
exhaust lift .629Intake duration at .050” 236Exhaust duration at .050” 242
LSA 113
ADV +4
I had to have the base tune adjusted because it would not stay running for the break in period…. I am still in the midst of the breaking it in. So I have not had it Dyno tuned yet. This cam does not seem to be very street friendly as anything under 1600 RPMs it wants to surge. They recommended that I replace the pushrods which I did with titanium but they did not recommend replacing the factory springs which I think are going to become an issue. Any advice and information on this cam set up would be awesome! 2012 base Corvette. LS 3
Rocker ratio 1.7Intake lift .629
exhaust lift .629Intake duration at .050” 236Exhaust duration at .050” 242
LSA 113
ADV +4
I had to have the base tune adjusted because it would not stay running for the break in period…. I am still in the midst of the breaking it in. So I have not had it Dyno tuned yet. This cam does not seem to be very street friendly as anything under 1600 RPMs it wants to surge. They recommended that I replace the pushrods which I did with titanium but they did not recommend replacing the factory springs which I think are going to become an issue. Any advice and information on this cam set up would be awesome! 2012 base Corvette. LS 3
Last edited by Xavier Bob; Oct 14, 2021 at 03:22 PM.
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2021 C6 of the Year Finalist - Modified
236° / 242° . . 113° LSA
____________________________
That cam has an overlap of +13°
Your stock LS3 cam has an overlap of -26.5°
That's a difference of 39.5° . . That's a lot, and Thompson Motorsports considered this cam "Mild" ?
____________________________
That cam has an overlap of +13°
Your stock LS3 cam has an overlap of -26.5°
That's a difference of 39.5° . . That's a lot, and Thompson Motorsports considered this cam "Mild" ?
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Joined: Mar 2011
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From: SW Florida
2021 C6 of the Year Finalist - Modified
You now have a cam that gives you a .629" valve lift, and a set of stock LS3 beehive valve springs that aren't even rated to .600" lift
I can't believe the stock LS3 springs you have in the engine now aren't going into coil bind.
I think you need to re-evaluate who you are doing business with !
Le Mans Master
Joined: Mar 2006
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From: Texas
I had nearly that exact cam in my C5. I absolutely loved it, but "mild" it was NOT. I had to have the heads milled to bump compression to get decent low rpm performance. Hell, even the guy working the starting line at the drag strip commented, "Nice lope, man!" 
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Joined: Oct 2019
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From: Cape May, NJ
when properly tuned and I am having East Coast Super Charging Dyno tune it what do you think I’ll get out of that Cam and extra 100 horse??
Last edited by Xavier Bob; Oct 14, 2021 at 05:09 PM.
Melting Slicks
Joined: Jan 2017
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From: CONCORD CA.
i had in my last engine, a Texas Speed stage 2. i loved the added mid-range. i had a nice idle too. it would hang around 900rpm's for a few seconds, then settle around 750rpm.
mileage dropped maybe 1 to 2 mpg. if it wasn't for the mechanic who installed the head gaskets wrong twice ( resulting in a totalled engine ), in May last year, i would expect to still be driving it now.
currently running a new LS3 crate engine ( all stock ).
mileage dropped maybe 1 to 2 mpg. if it wasn't for the mechanic who installed the head gaskets wrong twice ( resulting in a totalled engine ), in May last year, i would expect to still be driving it now.
currently running a new LS3 crate engine ( all stock ).
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Le Mans Master
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From: Southeast TX
Titanium push rods may exist. I just have never heard of them. If you did have them, they would cost WAY more than a hundred bucks though. Titanium retainers for your valve springs are common. I'm running them on my heads/cam LS3. I'm just about sure you're not running the stock valve springs either. Running stock LS3 springs with a .629 lift cam would result in lots of bent up ****. More than likely you have aftermarket beehives or dual springs with titanium retainers.
You definitely need at least a base tune for a healthy cam for that thing to run even remotely decent. That's not the cam's fault. ECS will get you lined out just fine.
As for as a power estimate, you're probably looking at high 400's...maybe touch 500 on a good day on a dynojet. That's assuming an M6 transmission.
Whether it's too big or not...it's there. You can learn to live with it or spend more bucks on another cam swap. It's bigger than I'd want to fool with, but some like a cam like that. Beauty is in the eye of the beer holder...or something like that.
You definitely need at least a base tune for a healthy cam for that thing to run even remotely decent. That's not the cam's fault. ECS will get you lined out just fine.
As for as a power estimate, you're probably looking at high 400's...maybe touch 500 on a good day on a dynojet. That's assuming an M6 transmission.
Whether it's too big or not...it's there. You can learn to live with it or spend more bucks on another cam swap. It's bigger than I'd want to fool with, but some like a cam like that. Beauty is in the eye of the beer holder...or something like that.
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From: Cape May, NJ
My apologies looking at the build sheet they are chromoly push rods at $95.00
I just ordered Manley .660 dual spring kit w/ titanium retainers from for $299.00
I just ordered Manley .660 dual spring kit w/ titanium retainers from for $299.00
Last edited by Xavier Bob; Oct 15, 2021 at 11:50 AM.
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From: SW Florida
2021 C6 of the Year Finalist - Modified
You will need the seals that fit the dual springs.
___________________________________
Stock valve guide seals look like these "hat type" seals
The valve guide seals you will need for the dual springs are shaped like this:
https://briantooleyracing.com/btr-valve-seal-kit-ls-vs-ls-kit.html
https://www.summitracing.com/parts/btc-vslskit
Last edited by Turbo6TA; Oct 15, 2021 at 12:45 PM.
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I'm really surprised they didn't have you install valve springs with that cam, as far as the surging goes, wait until it's final tuned before passing judgment, it may get better.
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From: Cape May, NJ
Can’t wait to get back up there for the final tune! However the break in miles are going on slow I still can’t drive the car yet and my wife doesn’t like driving it at the moment but she’s toughing through it and trying to put a few miles on each day I think I’m up to 150 out of 500 so far!!! LOL
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From: Erlanger, Kentucky
That is a huge cam. And recommending you stick with the stock valve springs? Sorry but WTF is wrong with that shop?
Assuming an auto trans, I wouldn’t go any bigger than 224 duration and a 114 LSA. Keep lift about .600. Manual trans you can go a little bigger but I wouldn’t unless your car is more of a track car.
When in doubt on a cam, go with the smaller one. You will still get 90% of the gains, have much better drivability, and stress the valve train less.
Assuming an auto trans, I wouldn’t go any bigger than 224 duration and a 114 LSA. Keep lift about .600. Manual trans you can go a little bigger but I wouldn’t unless your car is more of a track car.
When in doubt on a cam, go with the smaller one. You will still get 90% of the gains, have much better drivability, and stress the valve train less.
Last edited by Spaceme1117; Oct 16, 2021 at 07:59 AM.
