In my GM goodwrench engine I have the smallest cam know to man. My peanut cam from my old lo3 was probably better.

Anyways whats the highest lift I can go with a stock lo5 head setup. I plan on getting heads eventually BUT it will be awhile.

Id like to install a new camshaft.

I have the money to buy heads now but Im going to get a cowl hood, high rise z28 wing, and paint first

 

Safely without a spring change?

Use the Summit Cam # SUM-K1102

It includes this cam which is .420"/.442" lift, 204*/214* dur. @ .050", 112 LSA.

You won't have any computer problems with it. Plus it's just big enough to give you some "umph", but not big enough to cause those heads to starve the motor. You'll have plenty of retainer-to-guide clearance, and it'll help build cylinder pressure to make up for the sub 8:1 comp. ratio of that engine.

 

Ok the lo5 motor I have has 9.6:1 compression. It is supposedly a caprice cop car motor or something.

I have no computer so I dont have to worry about that.

In paceparts they recommend the lt4 cam. I might pick it up. Looks like its a decent camshaft and with 1.5 rockers shouldnt be to much lift for stock heads.

I plan on some world sportsman II heads eventually tho.

 

I was thinking of the $1200 Goodwrench motor when I said 8:1 comp. Sorry.

Anyway..... I have a set of 193 heads and I've checked retainer-to-guide clearance on them. The most lift I can run is .460" and still have .050" of space left. And these heads had a valve job, so the valves are sunk in more than new heads would be.

The LT4 cam is kissing .510" of lift, right? You have to have the valve guides machined down and buy new springs. IMO, those heads aren't worth the time or money.

PLUS you'll have to spend a butt load of cash on all the stuff to make that block handle a roller cam, because I know for a fact that LO5's came with flat face lifters.

The block may have all the provisions for a roller cam, but you have to buy a new timing chain, front retainer, roller lifters, lifter retainers, "spider" thing, and of course the cam.

All that stuff is gonna add up to well over $500, not including having the valve guides ground down. I thought you wanted a quick, cheap change to give the engine more *****?

 

If you want some more seal-retainer clearance, use the shorter Manley retainers.

With stock Z28 replacement springs and the Manley retainers, we were able to install a ZZ4 in a stock iron head L98 with room to spare. It's got @ 5k daily driven miles on it since the swap with no problems and more than a few 1/4 mile passes.



HTH

 

Ok my motor IS a roller motor. Its from a 1993 caprice police car. It has a roller cam, lifters, everything. Roller cam is what I need because the motor is a roller motor. Thats one reason I spent an extra 300$ on it instead of the 1200$ one. Its roller and has more compression. Probably less hp tho but IMO worth it.

Oh and the lt4 cam has .460/.480 WITH 1.6 rockers. So with 1.5s I should be ok right?

So your telling me with the z28 springs and retainers I could run the comp cam I wanted with ~.490 lift?

When I get the heads I wont have to worry but its gonna be awhile. Many other things before I throw down 1k for heads. But I can afford to throw down 185$ for a lt4 cam. Since I already have all the gaskets and timing set. My timing set is probably fine but ill change it anyways.

Hood, spoiler, paint and interior come first...then heads.

Im assuming the lt4 cam would be fine since paceparts recommends it for that motor?!

 

Next time tell EVERYTHING about your engine that needs to be known.

MORE THEN LIKELY you can use the LT4 (#12551142) cam that Pace has IF you're using 1.5 rockers. But you have to check the clearance.

No two engines are the same. Nobody can tell you FOR SURE if it'll work without checking your engine.

Bring the #1 cylinder to TDC and fill it with air or a 1/4" nylon rope to hold the valves up.

Remove rocker arms.

Remove spring retainers and springs on BOTH valves.

Install check springs in their place WITH the retainers you plan to use.

Bring #1 piston to BDC.

Put a dial indicator on the valves and measure the travel they have until the retainer hits the valve seal and/or valve guide.

Subtract the lift of the cam from that number. The clearance needs to be at least .050" (± .005").

While the valve springs are out, put them in a bench vise and squeeze them until they just start to bind. Measure them with dial calipers. Then back off the bench vise until the spring is expanded to the installed height (1.70" for example).

Subtract the closed height from the installed height to find the amount of movement in the spring. The difference should be AT LEAST .060" more than the lift of the cam.

If both of those are fine, then buy that cam

 

oooooo thats how you do it....lol.

Sure if you say so.

Might have somebody else do that for me.

 

ctandc you said you have been running the zz4 cam in a stock l98 heads with z28 springs. i have world torquer heads that i want to run with the zz4 cam but im not sure how long the springs that are in there will last with that cam. There good to about .560 lift but only have 100# seat pressure. don't roller cams have to have about 120-130 of seat pressure? what are the specs on the z28 springs

 

It's not so much the seat pressure as much as the spring rate that's important with roller lifters. Since roller lifters are heavier, they need more pressure at open height to control them at higher RPM.

Comp Cams makes a spring #981-16 that's #105 lbs @ 1.70", #295 @ 1.25" open. They're good to .490" lift AND the have a spring rate of #423!!!

Coil bind is at 1.150" (.055 total lift) so with .060" clearance, that leaves .490"

http://www.compcams.com/catalog/302.html

Pretty neat how that works, huh? :lala:

The best part about these springs is they're 1.254" OD, so no spring pocket machine work is needed.

You can find them at Jeg's or Summit for ~$60.00

I'd call Comp Cams to see what they recommend just to be sure.
1-800-999-0853

I called them to check about them, and they said they were fine for the cam I'm gonna run.

It's a roller cam, 210*/215* @.050" with .462"/.470" lift with 1.5 rockers, 110* LSA.

If you're going to use the 1.6 rockers with the LT4 cam, I'd definitely call them.