I have a 2002 A4 with 3.42 gears and no other mods. Does anyone know if the GM Hot Cam alone (no headers, etc.) will provide any noticealbe RWHP?

Also, what do you think this would cost for the parts and install? And would I be jeapardizing my warranty on the engine with this mod? And finally, does the PCM require any re-programming for the Hot Cam?

Thanks for any advice :cheers:

 

I'm not a big fan of the Hotcam, especially in an A4. The large split duration makes it idle rougher that I would like, and it would definitely require custom tuning with an A4. I've watched M6 cars stall more than once trying to pull their car on the dyno w/ the Hotcam. The single-pattern cams are making GREAT power, and they'll idle much better. I just installed the Comp Cams XE-R 224 cam (224/224, .581"/.581", 112 LSA) in my SS, and it's amazing at how docile this cam is on the street. Put the pedal to the floor, and it SCREAMS! I had the cam idling at 625 RPM right after the install. My PCM is currently at Ed Wright's in Oklahoma, and I had him set my idle in gear at 750 RPM and 800 in park and neutral. This cam, along with quite a few other single-pattern cams, will outperform the Hotcam by quite a bit. You'll pay more for the complete kit (springs, retainers, etc.), but you'll be much happier.

 

Thanks Trevor that is just the kind of info I was looking for :)

 

The Hot Cam is known to work very well on a car with stock heads, and because of its low lift (.525) it generally doesn't require new springs, retainers, etc.

 

The Hotcam comes as a package that includes new springs (same as LS6 springs I believe). No way would I run this or any other cam (including stock LS6 cams) other than the original stock LS1 cam with the stock LS1 springs, if you do you are just asking for bent valves and pushrods IMO. Springs are too cheap (relative to what you risk damaging) and easy to install to risk the potential problems of trying to use any non-stock cam with stock LS1 springs. As others have said, there are other cams that seem to make as much or more power than the Hotcam with better idle, but they do cost a little more. Not an area to skimp on IMO though, since the cam is the single most critical part in determining your engines performance and driveability. As for warranty, I've heard of at least one person getting an engine with Hotcam warrantied, but most dealers will deny warranty coverage for far less. Even though it is a GM cam, it is not original equipment and if something did go wrong, they could always blame the cam install if it's done anywhere other than a dealership. I'd check and see if I could find a dealership that would agree to still honor the engine warranty before I assumed anything. The XE-R lobes from Comp Cams will certainly make great power and idle very well, but I'd be afraid to run that agressive of a lobe in anything that gets driven alot. The load generated by those lobes and the stiff springs needed to control them are bound to shorten the life of the valveltrain significantly I would think, but that's just my opinion :)

 

Remember that the hot cam was designed for SCCA style racing in 6spd. cars. I would reccommend a different cam especially with an auto because when the car shifts it drops out of the cam's powerband. Also, if you ever did heads on the car, you would get poor results in low end toque and seat of the pants feel.

 

The powerband isn't a problem. A torque converter will solve that. :)
As for the springs, I recommend to anyone that races their car on a regular basis to swap out the stock springs with their stock cam! The seat pressure on a set of stock springs is right around 75-80 lbs. if I remember correctly, and they're just too weak. If you're going to stay with the stock cam, then I'd get a set of LS6 springs to swap out with. If you're going with any lift above .525", then I'd go with Comp Cams' 918's. I'm running them with .581" lift with no problems so far. They're good for .600" lift safely, but I don't think I'd want to try it. If you're approaching .600" or greater, I'd look into a set of dual valvesprings. You'll have to machine the spring pockets on the heads, though, for them to fit, so it'll be a major PITA if you're not replacing the heads w/ a ported set. If you are, then it's no big deal to have the added machine work while the heads are off and getting ported. With .600" or greater, you might want to consider some valve reliefs, too. :)

 

Most tuners are putting in 918 springs with any cam with less than 600 lift.Over that most are using a double spring if memory serves me right it is a 941 spring.Most reputable tuners will not let you get a setup that will over stress the valvetrain because they know it is their problem and will have to do the repairs.The LS6 heads most are using are CNC'd then hand done to get the most airflow thru them.As you can tell by my sig I have a very agressive H/C setup on '00 coupe, My idle is set a little higher than some at 850 also my rev limiter is set at 6400.Idle is very smooth and sounds pretty mean.Just to let you know how smooth, it is my wife's daily driver!My advice is before you buy a H/C package from any tuner test drive a few different setups to see which suits your needs the best.

Jerry

 

How much can I expect from a shop to change out a cam and springs? :confused:

 

How much do they charge?

 

Yeah, how much do they charge for a cam swap? :confused:

 

What I have been told it is a 20-30 hours of labor according to THE BOOK. Alot of shops will do it on a set fee.Depending on who you go to $1200-1750.It also depends on if you are just doing a H/C job or adding other items also(i.e. Ls6 intake, headers, etc.) just find a good tuner you trust, sit down with them and talk, and find out everything upfront before the works starts( est. length of time to be completed,Hp/TQ #'s ,and will they stand behind their work in writing if something is not right with the job).Good luck and have fun.

Jerry

 

The dual springs that shops are using are NOT the 941's. I don't know if you've followed the saga with the 941's, but they have been snapping like crazy. I would NOT recommend the 941's for anything over .540" lift! That was the main reason that Comp released the 918's. They needed a reliable alternative that would fit in the stock spring seats.
As for labor, if ANY shop tries to charge anywhere near $1,200 for a cam and spring swap just get up and leave! That's ridiculous! The average price I've seen from various shops is in the neighborhood of $450. MTI will do the swaps for $350 when they run a group purchase on their cams. Even then, I was only charged $390 at MTI to swap cams in my T/A in the summer of '00. The cam swap on my SS was $300. After you see a complete cam swap done in an LS1, you realize just how easy it is.