Woe is me, my son ( lcvette) is finishing the mods to his 95 vette today and
now threatens to whup me at the track. Really dont want that to happen
right now so before I give him a shot at it i better change cams and do some head mods also. I plan to lightly polish and port match the heads and put a new cam in. My son recommends something a bit more radical than the Hot -cam. He mentioned a crane hydraulic roller.We had discussed a solid lifter but i decided to stay w a hydr roller. He had posted the same question for me and some very good responses steered me from the high rev solid cams. I would like the car to pull strong to 6800.. Any advice will be greatly appreciated,, ty.

 

If you want 6800 rpm, I think you will end up with a solid lifter camshaft(roller preferred-of course). I'm in the same boat and plan to go this route.

Good luck.

 

Tx " No Go",

I figured the LT4 hot cam would pull me to 6800 since the car does nicely till the rev limiter cuts in at 6550..is there anyone out there that put the hot-cam
into an LT4 ?and with proper reprogram how did it do.. My son told me about a Crane Roller that does a bit better than the hotcam but i dont have the part number availible. Really am thinking about a solid roller too. Tx again for the post..u have a nice looking car..

 

I have the Hot Cam in my car and it seems to make good power up to the 6500 RPM range, The stock LT-4 cam runs out of steam in the 6100-6200RPM range but Im sure your car still pulls pretty hard to 6500 since you have the 4.10's
With your gears you could go with a CC306 or GTP 5 cam or equivilant. Both of these should let you rev to the 6800 RPM zone. you will give up quite a bit of low end torque with either one of these but your gears should help make up for it. If you are going to do some head work, do more than just port match because you are going to want to take advantage of the deep breathing that cam is going to want to do. I would suggest a full port job on both the heads and intake, the stock valve size should be OK and it will help maintain a bit of low end torque as well. If your going with a big cam and you are going to be spinning the motor to 6800 you will need a different set of valve springs and an adjustable rocker arm (stock LT-4 rockers are non adjustable). With these mods long tube headers are going to be a must, I cant believe the difference they made on my car. I picked up a solid 3-4 tenths and a solid 3-4MPH by installing long tubes and eliminating my cats.
My N/A times are in my sig, that time was run on a 95 Degree day with 90+ percent humidity with a 1.95 60' time. In cool weather Im hoping to get it to a 12.1-12.2@ 116-117MPH

Good Luck

Mike

 

Must be the day for cam questions. Here's what I just posted in another thread:


For the price, the GM hot cam (218/228) is pretty hard to beat, IMHO. Power is a bit peaky, perhaps, and torque is a bit off down low, but that's pretty common with most performance cams.

I had very good experience with a Comp 210/224 cam, a milder unit with excellent drivability, perfect idle, and a really flat torque curve.

The Comp 305 (220/230) is supposed to be an excellent street grind if you want something just a bit more than a GM Hot Cam.

I finally opted for a Crane 222/230. It has a slight lope that I like and comes on very strong. It does like fuel though so I wouldn't suggest it for an otherwise stock LT1 or even LT4 without larger injectors.

A step up from this is the Comp 306 (230/244) which is about as radical as I'd want to go on a stock displacement motor for the street. Strokers can tolerate more cam though.


What Mike (GS #775) said is good advice, too. You can see what kind of power the Hot Cam makes in his car. I would caution you, however, that while your motor may pull to 6800 RPM easily enough, that's really pushing it for a stock bottom end. If you are going to be in this territory frequently, you might consider beefing up the bottom end now rather than waiting for a spun bearing or some other mishap to occur. Not that I would know anything about that, of course. :lol:

 

I didn't realize the hydraulic rollers had that rpm capability...still seems little risky spinning it that high.

Also my stock LT4 runs into the rev-limiter at 6400 even though the factory tachometer will show over 6500.

Good luck.

 

You need to do a real good set of heads and then build a cam that fits the flow numbers. I shift my A4 at 6,700 but it will make power to 7,200.

 

It doesn't sound like you want to go all that hot...

I'm running a GTP 6 cam, the equivalent of a CC 306 with a tiny bit less duration and more lift. It isn't for the mild and won't come close to passing emissions, but if you're in to hunting vipers, then it's what you're looking for... I haven't done any dyno runs (soon), but the sotp meter says I'm going to have the greatest area under the curve when I shift my stroker @ 6400-6500 rpm. For a stock shortblock, either should easily be good for 6500-6800 rpm shift points with some stage II heads. (LT4 heads make for some awesome flow numbers when ported radically) For most, the above two are near the extreme end of 'streetable', and are generally part of a greater whole. I'm not sure how the LT4 timing set holds up, but you may need to look at a GMPP extreme duty set for a big high revving cam along with various other upgrades. A lot of people have done them and put them on the street, but you will know that you have a purpose built machine when you crank it up.

Programming will be necessary for best results.

The CC 305 is good if you want an aggressive performer with a milder idle and more (with proper programming) cat friendly emissions.

As far as lifters go, I'm running Comp Cams' R-series hydraulic roller lifters (I believe pn 875-16, this is from memory, so someone correct me if I'm wrong here) and they've handled my current and prior setups pretty good. My current setup includes triple springs, and you'll definitely need to upgrade those when increasing your lift @ rpm. A rev-kit can also provide some cheap insurance in case of a missed 6800 rpm shift.

If you want more than a LT4 hotcam, but want to remain somewhat mild, I'd look at the CC 305.


[Modified by nitrojunky, 6:34 AM 9/16/2001]