Digi7ech

I've got a '00 LM7 block I'm putting in my Rx7 and was told it had a LS6 cam but found it was just the stock truck cam.

I am planning on getting the cam because I want a decent bump in power.

I've already got yellow springs and pushrods out of a 06 LS2 GTO(pushrods are still 7.400 right?).

From my current research I understand that I need to find a 01 LS6 Cam because that will drop right in.

The '02+ cams have a .050 smaller base so .7450 pushrods would be required right?

I'm trying to keep the build cost down because I've got a lot of other parts to buy.

jfg455

iTrader: (5)

We used an 04 ZO6 cam and springs in an 01 5.3 with stock pushrods no issues. Best grind is the 04 cam.

Digi7ech

So do you just consider the .050 as slop/within factory specs?

LQ9CHEVELLE

iTrader: (2)

The looser fitting 7.400 wont hurt the motor, but it could make valvetrain clatter. If it dosen't make noise, you're fine. If its clattering from excessive slop, move up to the 7.450. Trickflow has them for $89 at summit, and they're much stronger than the weak factory pushrods, they're .080 wall hardended. Stock pushrods bend pretty easy once you start RPMing them, a little valve float in the mix and they're tweaked. That Z06 Cam will pull 6500+ on a 5.3, but the bottom end is gonna be a little soggy. 204-218 is a big split, and the 117 LSA is pretty wide for a naturally aspirated motor, with small cubes and those smaller heads. 214-218 or 218-218 on a 114 is a good cam for a 5.3, if your still looking for something that will pass smog, but will make more power all around, definetly alot more bottom end and be generally a little more aggressive. about .550 lift max to keep the LS6 springs happy, no more.

Digi7ech

This is for my drift car.

High rpm's and abuse are in it's future. I've got ARP rod bolts already. Looks like I'll get some pushrods to be safe with the higher rpm's.

Just put a bid on a 04 Z06 cam for only a $100 on ebay. We'll see if I win in an hour.

So did GM just push the yellow springs at their "limit" or did they use different springs with these higher lift cams?

LQ9CHEVELLE

iTrader: (2)

Lingenfelter uses this sping on smaller cams, and lists them as being good up to .570".....but coil bind isn't the only issue, as cams get larger, and rev higher, you need more spring pressure to control the valve and keep it out of valve float and bouncing when it returns to the seat. Anything more than around 220 @ .050, i wouldn't use them. GM uses them with their "hot" cam kit, which is 221-229, but @ only .525 lift, and the cam lobes are pretty gentle and slow compared to most cams

BandAid

Can anyone tell me what cam is best for the LM7 motor,I am gonna run NA for now and then turbo Carb the motor in a yr or two...
also what intake manifold would fit the LM7 motor,for carb application... thansk for any help.. Dennis

BryanD

do you know who makes off-the-shelf cams with those specs? i found a Comp that is 212-218 115 LSA, but thats as close as i could find.

i have a Z06 cam/springs/injectors to put in my 5.3, but the more i read i don't think it is what i want. this is for a rock crawler / buggy and low-end torque is WAY more important than full throttle pulls - although i do take it to the sand dunes several times a year, so that would be nice too. but if i had to choose it would be low-end for sure.

also, i thought i read somewhere that with the cam swap on the 5.3 a larger throttle body is recommended? no?

battsup

I'd be interested in this as well, low end torque is what you want for street cruiser.