mean cam?

[fastTa]

Originally posted by Jay 02 TA ws6
Kevin, do you have a little more info on that cam? For instance, what RPM does it redline at? And what kind of highway fuel economy would it get?

I am willing to sacrifice quite a bit of road manners as far as idle, lopiness, and surge are concerned... but I want highway fuel mileage to stay above 24 or so...

I also want to end up with a cam that would put my shift point at around 6700 or 6800 RPMs...

If that's not the cam for me, any ideas what I should be looking for?

What's up Jay. Here is the description from the website:

Thunder Racing Custom Camshaft - T-ReX v.2 - 242/248 - .608/.612 - 110 lsa 3500-6700 RPM Power Band. Violent mid-range & high RPM power. Requires computer tuning, 4000+ converter on autos, 4.10's or greater on manual trans cars. Due to the fast ramp rate of this camshaft, the use of 1.8 rockers is not recommended. Due to the extreme nature of this camshaft, piston to valve clearance must be verified when using modified cylinder heads.

With your stock heads, piston to valve clearance should be fine. This cam has quite a bit of overlap, meaning don't expect this to be a fuel economy cam but with a proper tune, you should see around 18-20 on the highway. If I had a stock LS1 though, this would be the cam of my choice.

There is a 01 Black SS here in town that has this cam and it sounds righteous.

[Jay 02 TA ws6]

Thanks for the info... any idea why I would need 4.10s in the rear to go with this? That doesn't make much sense to me...

18-20 mpg is a more than I want to sacrifice there, so I guess I should keep looking. Although the powerband going to 6700 sounds great...

I also plan on possibly going with Patriot Stage 2 heads, so what power I sacrifice with a milder cam, I am sure that I can more than make up for

My goal with this is to throw 3.73s in the rear, but still being able to stretch each gear to a higher MPH than I do stock thanks to the higher RPM cam... for instance, shift out of 1st at 50 instead of 45, 2nd 80 instead of 70, and so on... if I can make more power at the engine, and stay in the lower gears longer, I will be pretty happy

[fastTa]

When you go with bigger cams they make more mid-range and upper rpm power, but they significantly sacrifice low-end torque.

You need a numerically bigger gear that increases torque multiplication in order to get your car going easier while you are accelerating below the cam's powerband.

For instance the t-rex's powerband comes on at about 3500 rpm's. So under 3500 rpm's the torque is a little soft. This is why they suggest at least 4.10's with an M6. But once you get to 3500 at WOT, hold on!

If you want good gas mileage look for a cam with at least a 112 LSA.

[Jay 02 TA ws6]

OK, that makes sense with the more aggressive gears... but how much of a low-end sacrifice are we talking? 200 ft-lbs instead of 300? I mean, I could live with that...

112 LSA, huh? Good to know, thanks a lot Kev.

[abmcbballer]

I think i get it actually. I have 3.73's, so i have a really good bottom end, would it make sense to retard the cam a little so i could have the advantages of the 3.73's and get back a good middle/top end?

[Jay 02 TA ws6]

I remember a discussion I had a while back with one of the gurus on ls1tech... basically the jist of it was that top end power isn't really limited by the cam itself, it is limited by the intake manifold. The cam can only make the top end power with an aggressive LSA, and that makes it very lopey...

...so anyways, I guess my question is, is it even possible to find a cam that would put my shift points at 6700-6800 without having a really aggressive LSA? I would have to believe that there is... I mean the LS6 stock cam has you shifting around 6400... this is only 300 RPMs further... that can't be THAT much more aggressive...

[fastTa]

Originally posted by abmcbballer
I think i get it actually. I have 3.73's, so i have a really good bottom end, would it make sense to retard the cam a little so i could have the advantages of the 3.73's and get back a good middle/top end?

You could retard the cam, but don't go any more than 4 degrees for a street driven car.

[fastTa]

Originally posted by Jay 02 TA ws6
I remember a discussion I had a while back with one of the gurus on ls1tech... basically the jist of it was that top end power isn't really limited by the cam itself, it is limited by the intake manifold. The cam can only make the top end power with an aggressive LSA, and that makes it very lopey...

...so anyways, I guess my question is, is it even possible to find a cam that would put my shift points at 6700-6800 without having a really aggressive LSA? I would have to believe that there is... I mean the LS6 stock cam has you shifting around 6400... this is only 300 RPMs further... that can't be THAT much more aggressive...

Jay given what you have told me I think you would be happy with the above mentioned TSP 231/237 .598 .595 112+2 cam. This has a powerband of around 3400-6700 I believe.

[Jay 02 TA ws6]

What about this from Comp Cams?

Dur. @.050 228-230 | Lift .571-.573 | LSA 112 | RPM Range 2200-7200

"Superior top-end power. Needs LS6 intake and computer modifications"

[fastTa]

Originally posted by Jay 02 TA ws6
What about this from Comp Cams?

Dur. @.050 228-230 | Lift .571-.573 | LSA 112 | RPM Range 2200-7200

"Superior top-end power. Needs LS6 intake and computer modifications"

That is alot of lift given the duration and amount of split duration. Comp most likely does this to give it a broader torque curve which in turn makes it more "street friendly". That cam would be OK if you really wanted a "streetable cam", but that cam has pretty non-aggressive flanks(ramps) and very mild clearance ramps because of the nature of the "Extreme RPM High Lift" lobe design.

If low-end street manners are really your primary concern and winning races at stop lights is your secondary concern , well then something along these lines would be perfect. Butt................

If you want to put down some real power and blow the doors off modded C5's, then go with something at least in the 230's range.



There is so much more to cams than just duration, lift, LSA, IC, and ramp rates. It is about making all of these work in harmony, and having complimentary duration and lift to produce good velocity into the cylinder and sometimes too much lift can kill velocity and in turn kill HP.

If you look at the bottom of the list of LS1 cams on the Comp Cams website, you will see the "XE-R" grinds and Comp says that they are for race only apps. That is total BS! Those aren't near big enough to call them "Race Only". They just have to put that disclaimer in there for the idiots who don't know jack about motors and pick that cam to install only to find out they can't tune it and it runs like sh!t.

Unfortunately Comp Cams does not do near the R&D on LS1's as the actual LS1 speed shops, so their "off the shelf" grinds aren't usually considered to be great power makers, they are however considered to be "street friendly". I don't mean to bag on Comp. Comp Cams makes an excellent camshaft, but I just wouldn't choose one of their "off the shelf" grinds. Go with a grind that has been proven time and time again on the track and the dyno.

As long as you stay under 234-238 duration on a 112 LSA, you will have no problems whatsoever on the street. It is amazing what a good tune can do with a "big" cam.

I had a 239/245 with a 3200 stall in my WS6 before I pulled it apart again this last time and it was absolutely fine on the street. And it pulled like a mutha on highly modded C5's

[Jay 02 TA ws6]

PM'ed you...

[fastTa]

Originally posted by Jay 02 TA ws6
PM'ed you...

Tryed PM'n you back, but your mailbox was full, so I sent you an e-mail.

[Jay 02 TA ws6]

Crap... sorry, I haven't used that email address in forever, and it was de-activated by Hotmail...

I cleaned out my PM box though...

[fastTa]

Originally posted by Jay 02 TA ws6
Crap... sorry, I haven't used that email address in forever, and it was de-activated by Hotmail...

I cleaned out my PM box though...

I'll re-PM you.

Man that almost sounds nasty!

[Jay 02 TA ws6]

Originally posted by fastTA
I'll re-PM you.

Man that almost sounds nasty!

Did you send it?