rocksws6

iTrader: (4)

Are you saying that the LS6 heads are less efficient than the 5.3's?

Jpr5690

iTrader: (13)

Im Saying That The 5.3 Satge 2.5 Heads Make More Power Than Stage 1 Ls6 Heads

Jpr5690

iTrader: (13)

And If You Can Make The Same Power With A Smaller Cam Its A Good Thing As Who Tries To Use A Bigger Cam When There Is No Apperent Benefit

RareBreed0295

iTrader: (35)

Anyone else..?

CALL911

iTrader: (17)

I have been contemplating this exact same question for the exact same reasons. Here is what I am going with;

I will be opting for the MS3 and the 5.3 stage 2.5 heads. Given that the heads will out perform the stage 1 LS6 heads, but also taking in consideration that the MS4 will make a little more power than the MS3, you are talking maybe 5 RWHP difference from the two (TSP agrees with this estimate). It just makes more sense to me that the drivability being better on the MS3, and the slightly less peaky power curve is all the more reason to choose it over the MS4 combo.

If you go the flycut piston route, then take advantage and just go all out on the heads, and go with the MS4. But it sounds like you are in the exact same boat as me, and want to avoid flycutting the pistons.

As for the springs, I wouldn't worry about that either as the dual PRC springs that come with either of the kits will well support the high RPM abuse you will put them through with either cam.

RareBreed0295

iTrader: (35)

Im actually going with a totally different setup now. I talked to John at TSP and im going to go with the 2.5 Ls6/Trak cam. I have seen ungodly dyno sheets from this setup. It also makes huge torque. I will have the heads milled and i also dont have to flycut.

CALL911

iTrader: (17)

Bigger expected numbers than the MS4? If so, I would be interested to see what kind of power curve it has in relation to the MS4, as the MS4 is already super peaky and has very little low end.

RareBreed0295

iTrader: (35)

This is a dyno sheet i found on the site. I found this and this changed my mind.
https://ls1tech.com/forums/generation-iii-internal-engine/758749-patrick-g-tuned-my-trak-cammed-prc-ls6-2-5-s-car-results-inside.html

CALL911

iTrader: (17)

I'm not sure why it changed your mind. That guys dyno numbers were off (as the shop even mentioned), not to mention it was dyno'd in Texas where the humidity and elevation are perfect for peak numbers. Disregaurding all that, and say it did that power level in the middle of the country somewhere and the numbers where legit, it still is the same power level as one could expect from either of the cam combo's you are asking about in this thread to begin with.

One guy stated it had great mid range, but the graph shows the same low numbers in the low and mid range, and the power not coming on until 4500 or so (which again is almost the same as you would find with the MS4 or MS3).

It seems pretty much like the same as either the MS3, or MS4 cam I guess is what I am saying.

RareBreed0295

iTrader: (35)

43x torque at 3900rpm seems pretty good to me...

CALL911

iTrader: (17)

I guess it does seem to make a little lower peaking torque, but keep in mind all of this was with the stage 2.5 LS6 heads vs the stage 2.5 5.3 heads (huge difference right there). Take the heads into account for everything, and I'll bet you'd see similar results with either the MS3 or the MS4, as the huge cams really need to breath, so anything you do to help that (heads and intake) is going to help exponentially.

You mentioned that there are tons of threads out there of dyno #'s for the MS3 and the stage 2.5 PRC 5.3 heads. Do you have any links of them? I am curious to see someone's MS3, 5.3, 2.5 heads combo dyno graph compared to the trak cam.

CALL911

iTrader: (17)

This guy made almost the same RWHP but had only stage 1.5, 5.3 heads and an MS3,
https://ls1tech.com/forums/showthrea...hlight=5.3+ms3

RareBreed0295

iTrader: (35)

https://ls1tech.com/forums/showthrea...hlight=2.5+5.3

https://ls1tech.com/forums/showthrea...hlight=2.5+5.3

RareBreed0295

iTrader: (35)

I have been looking at a lot of different setups....but not sure what im going to do. I will be giving John another call tomorrow before i decide. I am either going with the milled 2.5 Ls6s or the milled 5.3s. Im not sure which would produce more hp. Since the Ls6s can take a bigger cam, will it produce more hp?

CALL911

iTrader: (17)

5.3's are a much smaller head than the LS6 heads. Having each ported to stage 2.5 won't make a difference. The LS6 2.5 heads will yeild more HP (and a bigger sticker price as well). If you are going to get either of those choices milled you are looking at getting back into the flycutting though. Milled will yeild yet more power, but will cost extra to have milled, and then even more for the flycut. But if money is no object, and you are looking for the most power this may be what you are looking for.

As for me, I am looking at driveability (to an extent), as well as most cost effective power which would keep me from flycutting which would also keep me from milling the heads.

RareBreed0295

iTrader: (35)

ttt..

RareBreed0295

iTrader: (35)

If i went with the MS3 and the milled 2.5 Ls6s....i shouldnt have to flycut should i? I know you can have the heads milled and still fit the Trak with no problems.

CALL911

iTrader: (17)

I am not familiar with the Trak, but I believe you will need to flycut with milled 2.5 LS6 heads (or 5.3 heads) and a MS3.

RareBreed0295

iTrader: (35)

bad i got to just post something so i can see the 2nd page...hopefully this will get fixed soon.

RareBreed0295

iTrader: (35)

If the Ms3 does require flycutting...ill probably just go with the Trak.