MostWanted

Do I need to get the entire Hot Cam Kit that includes the GMPP 1.6 Roller Rockers, valve springs, retainers, valve locks & shims that goes for about $659? Or can I get by with just the Hot Cam itself that goes for about $219? If I do go with the Hot Cam, how much and what kind of performance will I get? How will the engine idle? How will it sound? I know I have a lot of questions but I spun the bearings and have to get a new engine and I want to beef it up just a little. Thanks in advance for the info!

qkvette

if you have stock valve train, i think it is better if you pick up the whole kit because of the following:

1) stock rocker are only 1.5 which would give you only .496 lift instead of .525
2) the stock valve springs may not be able to handle that much lift

as far as the prices the kit goes for 499.95 as scoggin dickey and the cam goes for 175 according to their website. and as for hp it is supposed to be good for atleaset 20-30, but someone will correct me if i'm wrong. i have this on my car and on by brothers's and we both pass smog here in CA, and it is a really good cam for the price.

good luck,

joel

96BLKTN

$479 @ http://www.samtaylor.com.... :thumbs:

MostWanted

So SamTaylor is selling the same kit for $489. Wow! What a difference from $659.


[Modified by TorchRedXCVI, 7:50 PM 4/19/2004]


[Modified by TorchRedXCVI, 8:19 PM 4/19/2004]

vader86

That price seems alot higher than I'm used to seeing for the kit. :skep:

The idle is just a tad lumpish, something you'd notice but definitely not enough to cause vacuum problems.

You should buy different springs than those offered in the kit, I would go tougher.

MostWanted

There is a Technical Note that says: "This kit does not include roller tappets. See valve lifter section for the lifter kit. street rods below 450 horsepower. Use P/N 10108697 for single rod replacement." Do I have to have the roller tappets or can I use the stock ones. Sorry about all the questions...these types of mods are all new to me.

Corvette Kid

Your stock LT1 tappets are roller. You're good to go with them.

tobijohn

You would be a good guy to ask this question. I was researching the same thing - Hot Cam in an LT1 with an auto. I found a few threads in the archives that mentioned that the Hot Cam and an AT weren't the best match but none of the posts that cautioned against this elaborated on specific issues. What's been your experience? Thanks...

tjwong

There has been many that has installed that cam in A4 cars without any problems. I installed one in a F body a few weeks ago and so far there has not been any issues other than smiles :)

Renegade21

Passes smog in California...that's exactly what I wanted to hear :cool:

How much do you guys think it would cost for a mechanic to put this LT4 Hot Cam kit in for me? I am not very mechanically inclined at all, so I'm thinking having somebody that knows more of what they're doing would be better. Any estimates?

kman0066

Be easy on the 6500rpm runs this cam allows though. I got the cam and love it, but man I wonder if the extra RPM's are what killed my old grenade, I mean LT1. Definitely get the kit, not just the cam. The RR's alone will help out a decent bit in the HP department.

$500 for the cam install would be good. That's the best I got quoted, but I ended up installing it myself. Maybe add $100-$150 for the springs install. This is without parts which will include new valves seals, intake gasket set, timing gasket set, oil/filter, antifreeze, RTV.

The lifters and push-rods need to be inspected and replaced as necessary upon install. The timing set, I'll leave this to others. All I can say is that I exploded a motor with the stock timing set and it didn't fail even then at 95k miles. I now have the set from Lunati which was cheaper than the stock set being the main purpose.

As a possibility, think about having the motor rebuilt while you are at it if you are nearing 100k miles. Just even some new bearings and rod bolts would be good.

Nathan Plemons

The Hot Cam kit will make good power and you should really like it. If you really want to spin high RPM's though I would take the springs that come with the kit and sell them. Then get a good cylinder head shop to set you up with some really good springs.

For that matter if you can get the work done cheap enough install a set of large springs. This will probably interfere with the GM rockers though, so you'll have to get something with more spring clearance. When you do it this way it doesn't make a lot of sense to buy the kit, since you wouldn't be using the springs or the rockers.

If you're going with different rockers you can always try out some 1.7's to get just a little more kick out of it, although the performance gain of 1.7's on unported heads is as of yet unproven. Most rockers aren't self aligning so then you're into hardened pushrods and guideplates. To do that right will cost you around $100. To really do it right you install 7/16 studs instead of 3/8. A set of Comp Pro magnum lifters would be nice too.

Hmmm..... seems like this is getting really expensive really quickly. You can basically duplicate my setup and it'll be very reliable, but it's gonna cost. It didn't seem so bad when I did it, maybe it's because I didn't have to buy all the parts at once. If money is a serious concern then you would probably be just as well off with the kit.

:cheers:

qkvette

with my car (383) i had to bump up the idle to 900 and also the same for my brother's 86. i also had to retune and burn a new chip to get the a/f ratio in the 128 BLMs. i'm now in the process of either rebuilding the 4l60 or switch it to keisler tremec 5-spd kit (not available til june), so the car will sit for about a month or so. another thing for autos, is to make sure that your cam mathces with your stall spped of the converter. my brother's is at 2400 and mine was at 2800. both seem to be okay, but if i rebuild my tranny i may go back to 2400. not sure if having the 2800 on the stree added more wear on the tranny.

good luck,

joel

tobijohn

Thanks Joel. I wonder if the cam/TC was the mismatch that people were alluding to in those archived threads. If so, does anyone know what the optimal TC stall speed would be for the Hot Cam (and CFI-EFI, if you happen to read this, stay out of it - you know what I mean :)), thanks...

LT4BUD

Depending on what you guys decide I have LT4 parts available.
http://forums.corvetteforum.com/zero...&id=1547090928

Frankly, I have heard one LT4 with hot cam idle and drove it. I would question how well it would work with the stock torque converter. Hot cam is great setup, but I am sure in the long run a TQ with higher stall speed would need to be part of the package.

I am sure that stock LT4 cam would work with stock auto and, especially with a liitle head work, ought to result in really sweet package with very mild manners.

Just my opinion, don't really know anyone who has actually done hot cam in automatic.

Nathan Plemons

The stock LT4 cam really isn't that much more aggressive than the LT1. Most of it came from the extra lift provided by the 1.6 rockers. That being said you're right it should work well in an auto.

LT4BUD

Well what I am suggesting as one alternative (there are many good ones) is to upgrade to a complete LT4 valve train which would include cam, 1.6 rockers, springs, timing chain, etc. This in conjunction with a little headwork should result in a least as much power as an LT4, depending on the headwork.

Actually going by memory to just put in a LT4 cam with 1.5 rockers would be milder than an LT1 cam, a performance loss.

Could do same thing with Hotcam....more power, but sacrifice some smoothness of idle which might push a stock torque converter stall speed.

Nathan Plemons

Well let's just take a look at it, from this website http://www.9c1.com/technical/LT1_rebuild/ar99928.htm

92 LT1 cam was__ 205/207___.450/.451___117
93-95 was ______ 202/207___.450/.460___116
96 LT1 was ______ 200/207___.447/.459 ___117
96 LT4 was ______ 203/210___ .476/.479 ___115 (with 1.6 rockers)

Do the math in reverse and the LT4 has 1.5 rocker lifts of .446/.449 resepctively. The durations are all very close and the lifts are all very close as well. The LT4 did have the smallest LSA of the bunch, which is probably why the LT4 didn't have EGR. Basically there probably wasn't 5 HP between any of the cams. :cheers:

lspalding

Just to add my .02. Better springs, yes. Higher stall, yes. Send a note to Vettetech81. He just put a HotCam in his LT1 with higher stall converter. He did the work himself and is happy with the results.

LT4BUD

Nathan,
Very interesting cam comparison. I quess it shows the biggest gain in the LT4 over LT1 must be in the heads & bigger valves. I was of the impression, obviously not correct, that the cam played a bigger role in the power gain, but it is, like always, the result of a coordinated package.

Thanks for the info