LS4 Performance - Gen IV cam changes

Lol this throws a twist for installing cams in 06+ Gen IVs:

The cam on the left is out of an 05' GTO's LS2 that im rebuilding for the owner of the car ( the block below it)

And the cam on the right is out of an 06' Vette's LS2

As you can see they changed the cam design to use a big bolt in the center now instead of 3 small ones like all LSx's used before.

Looks like ill be OK for my car since i have the "new style" one, but this would require using an older LS2 timing set to work with an older style 3 bolt cam.

http://img101.imageshack.us/img101/4614/img00019jf.jpg

http://img250.imageshack.us/img250/1561/img00026pv.jpg

ghaaaaaaaaa
:(

Tom, the Montes getting a cam???

Tom, the Montes getting a cam???

Yes.

1.8 Ratio rockers for now though. The motor just about has to come out to do a cam.

are you changin springs too? or just throwin the rockers on and seeing what happens?

Just ordered the harland sharp 1.8's yesteday. they take .480" to .508" so the stock springs should work ok. If it has valve float (im going to wind it to 6500) then i will swap them for 918's. But being they are lighter, have less friction valve float should be very minimal.

hmmmmmm
i hate being second in the race!
damn you!

Nitto drag radials are next on the order sheet!

Just ordered the harland sharp 1.8's yesteday. they take .480" to .508" so the stock springs should work ok. If it has valve float (im going to wind it to 6500) then i will swap them for 918's. But being they are lighter, have less friction valve float should be very minimal.

where did you order them from? I would like to buy a set also.

summitracing.com

part # csp-sls18

Wondering why you decided to go with HS rockers? Heard some people having bad experiences with them.

price, ease of install. im not really pouding them with a fast ramp cam, HUGE springs are really high rpms. They should hold up ok.

summitracing.com

part # csp-sls18

thanks, I am going to order them.

What kind of gains are we looking at with the 1.8 rockers? I went 1.9 rockers (up from1.6) in my Comp G and it made a world of difference, and they claim 20hp to 25hp with other mods. Just curious if the LS4 would see the same kind of gains.
Tate

UPDATE:

Well i left my camera at work so i couldnt snap any shots. But i got them and swapped them in last night.

The front set was super easy, its akward isntalling them because the two rockers are connected by a pin and always slid off one another when trying to put them on, and trying to hold the new pedistal on the screw too while trying to line up the screw in the mounting hole was a bitch.

The rear takes some patience, working under the alternator on the right most cylinder is tough and you will need a will need an allen wrench on a socket to make this go quicker.

Buttoned it all up, fired it up, pretty noisy for the first 10 sec then got whisper quiet. Grabbed the lap top and logged it and took it out and tested it. First impressions were like eh... i cant really feel it but again the road were kinda damp and would spin through 1st into 2nd but i was like hmmm this thing really seems to pull HARD from 55+

So i look at the log and the delivered torque was up alot from 4G +from 329ish normally to 355 consistently. So i noticed it was running a touch lean (880Mv) so i fattened it up 3% and raised the rev limiter to 6600 and shift points to 6400. Tested it and was greeted to valve float and nose over above 6200 and a blinking SES light indicating a random misfire. So it could use springs if you wind it higher.

So i turned the rev limiter back to 6300 and shift points at 6100 and tested it with the new fueling and it hooked kinda in 1st and WHOLY FUCK! does the thing just pull like a freight train! It never got to 100MPH so fast LOL Its not like a diff after a cam but its enough to feel once the tune is right on. and my grand total peak torque the scanner sowed was 366 at 4700! that 60-80 just feels wicked now!

ghaaaaa
you may have sold me on them. you suck!
non adjustable right?!?!

come with guide plates?, did ya change the push rods as well?

clears the stock valve covers?

I think Vinci Hi-Performance in Flordia tested a Impala SS with 1.8 rockers and claimed 18 hp and 16lbs tq gain at the wheels.
http://www.vincihighperformance.com/impalassMAINPAGE.html

I moniter the engine delivered torque in HPtuners as well. Stock I was seeing around 310-325tq at WOT, now I'm seeing 350-375 tq at WOT(colder weather).
http://i45.photobucket.com/albums/f61/botsie/NewBitmapImage-1.jpg

25 degrees timing and + 2.3 trim at WOT... I run 30* with 0 trims at WOT, perhaps i should try and drop it some.

this should be interesting soon.

left over z06 cam from my GTO rebuild + 323ci + 243 heads + HS rockers...

shit. it's going to be a deceptivaly fast little mouse. god I could see you in the 12's with headers..

so much for leaving the monte alone....

this should be interesting soon.

left over z06 cam from my GTO rebuild + 323ci + 243 heads + HS rockers...

shit. it's going to be a deceptivaly fast little mouse. god I could see you in the 12's with headers..

so much for leaving the monte alone....

we'll go 12's without headers, and possibly on the stock cam as well.
:)

i mean in normal street trim, not w/ DRs or slicks.

i mean in normal street trim, not w/ DRs or slicks.
lol
during the summer dr's will be my normal street trim
:D

lol .