Hotwire

thanks guys, I reckon I'll have to bite the bullet and tear it down sometime. I can almost swear that the cam is right. My friend and I both triple checked it to make sure it was right, I had read that problem too much before I did the conversion.

I might borrow a friend's degree wheel and get a dial indicator on on a rocker arm to check the cam versus pulling the motor out of the truck and going through all that.

I just got back from the track, ran a 8.38 @81.63mph, 60 ft = 1.835 on a 1/8th track. Does that sound like I don't have enough power?

94IMPALASS

It does sound like you are down on power some. When you do get it figured out please let me know what you find as I keep a notebook of these thing for anyone that may have similar issues.

Kreinmc

Yes i was one of the ones who put it in a tooth off and it ran like complete crap. I had to launch it at 3k just to go. The car was much slower than it was before i even put the cam in. After i fixed it, it was unbelievable how fast the car was. I probably went from 100mph traps to 112mph traps by having the tooth off. And i also agree that a tune really won't do that much especially on a hotcam. Maybe 5-10 hp. The stock tuning works great on these little cams.

Kreinmc

Sounds like your truck will go about 102-103 in the quarter which is much slower than it should be.

94IMPALASS

I typically see 15-20 in gains or more on a program for the hotcam over the stock tune as well as driveability. But his truck should make even more power than that even with a stock tune.

LilJayV10

I don't mean to high jack your thread but I do want to ask a question and hopefully someone can point me in the right direction. What is all needed to do tuning yourself and how hard is the learning curve. The reason I ask is, I have 3 friends with 4th gens and all are doing cam swaps and one I am doing a head/cam swap/engine rebuild for. Now instead of everyone spending the money on a mail order tune it seems to me that it would make more sense for me to start learning on how to do this stuff now. The 95 Z is getting a hot cam, the 94 T/A is getting a cc305 cam and the 93 Z is getting a rebuild with heads/cam and all the bolt ons. Could someone point me in the right direction to learn about it? I don't have a degree in engineering, but I am pretty smart

94IMPALASS

Using the software at www.tunercat.com you can make these changes. The www.lt1edit.com website has answers about tuning questions and you can post there. And I believe there is a tunercat forum. Also you can email me if you have any questions and I will gladly help you. Do lots of reading, asking questions, and make your changes slowly and observe the effects.
Later,
Bryan

LilJayV10

Thanks, I will PM you sometime this week. I appreciate the info.

Jason

Hotwire

Mines pretty smooth all around, has a lopey idle, but off idle and drivability are fine, got 19 mpg going to atlanta and back, 13.5 mpg around town w/ the stall, got my tune to where I'm 122 blms cruising, etc etc. put new o2 sensors in, map

remember, I'm running a a4 w/ stall through a steel two piece driveshaft from the 80's w/ a carrier bearing the size of roseanne barr's thigh, complete custom exhaust, not mandrel bent, etc etc..

I looked up lt4 dyno on google and came up w/ the lt4 registry page, made me about cry, going to try and check the cam this week.

thanks everybody, Bryan, I'll let ya know what I find, thanks man. It might be the short block, I didn't do anything to it when I did the conversion cept for the high volume oil pump.. need to check compression, but have to pull headers to get that done, so it'd be a cold compression test.

Hotwire

just a quick update, got some money for my b-day, ordered a cam degree kit, should have it here mid week. hopefully i'll be able to quickly determine whether the cam timing is my problem or not. if it is, might yank the motor, fix my oil leaks and install a heavy duty timing chain, once I sweeten up the wife enough.

JodyJ

I don't know if this was suggested, but have you tried to re-adjust the rocker arms? How much are you going pass zero lash? With my Comp Cam "R" series lifters, I'm running 1/4 pass zero lash.

Jody J.

Hotwire

i adjusted them w/ the motor running, the bowtie rockers are sweet, they redirect the oil to the fulcrum bearings versus letting it shoot straight out. I did have to use an aluminum foil shield to keep it off my headers.

I loosened them up till they were noisy, brought em down to 0 lash, then went 1/2 turn. still running the stock lifters. thanks for asking. I will loosen them all back up when I check the cam, and may try 1/4 turn.

GREGG 97Z

I can vouch for Bryans hotcam tuning abilities, I just put down the dyno numbers below this weekend with his program with just the hotcam kit on bone stock heads and boltons. The car is running like a beast, I was completely blown away with the numbers! Thanks again Bryan and I sent you an email

GREGG 97Z

I really wouldnt recommend adjusting the rockers with the motor running. I tried it that way and I had **** all screwed up, my car initially was running pretty bad after trying to adjust them like that. I went back over them and adjusted them by the method of brining #1 cyl to TDC and adjust 1/2 the rockers, then #6 TDC and doing the other 1/2. I went by the method listed in the Haynes manual. I only adjusted mine to right between 1/4-1/2 turn past zero lash (3/8 past) and havn't touched them again in a year. It's been running incredible so far

Hotwire

Can you please elaborate on the method? engine hot/cold? loosen rocker, then bring down till pushrod stops moving? I've tried the spinning pushrod trick, but mobil 1 synthetic makes it damn near impossible to get repeatibility. did you loosen all the rockers, pump up oil press, then do it, or just shut it off, yank the covers and go? I've heard so many damn black magic stories on here, it about makes me want to pay someone to do it right.

when I have the degree wheel setup, I'll probably do the same method you described, got the service manuals, will look up their method, but would also like to know haynes for reference.

Thanks.

Jeff