Denny McLain

I may have posted a little premature.......Just opened your dyno run and it stops @ 6000 rpm. If you take it up to 6500 you'll see more power. You made a giant jump from being a bit rich (for max power) to maybe a little lean. Looks to me like your just starting to tune the car and you need to make a bunch more tuning runs to find what the car wants and eliminate any possible thing that are keeping hp down.

We did 21-22 runs today tuning the car and are just warming up to get into the real stuff. Keep with it and you'll find more power. You just started.

SS RRR

that torque curve don't look very healthy. Looks like the engine is suffocating.

yotaman96

That was actually my 1st run without some extra tuning, but it's the best example of average power I was receiving. The last run actually had a spike, so the #'s weren't accurate, but the torque curve looked better.

97s10ondubs

How are the rockers adjusted? I only go about 1/4 turn on my autozone replacements and it seems to do the trick.

FastZinTennessee

Don't worry about low dyno numbers until you have track times.

Kearn

hi,
Thanks for all the replies and sorry for the lack of info on my part. I rebuilt the motor last summer along with putting in all the performance mods. The only mod that I have done that wasn't last year was the CAI. I rebuilt the motor last year, all new rings, bearings, etc. Forged pistons. LT4 knock module already in. New clutch along with everything else: Spec stage 3. Oil change a few weeks ago. I have no cats, and I removed the smog pump. I'm not too sure about the knock retard, I haven't scanned my computer in a while. As for going to 6500, I don't think 300 rpm will make up the difference, thanks though. Zero lash was adjusted according to shoebox's (I think) website 1/4 turn just like you said I believe. The dyno is a dynojet and the run was done in 4th gear. Thanks for all the help. Any more questions or solutions please post.

SStrokerAce

All the suggestions are right on. When something does or doesn't work people want to blame the parts, but if those same parts or exact copies make power on another setup then it's not that. Knock retard among a host of other things is usually the problem. Iron out the details and you should be where everyone else with the package is. The guys who get killer numbers aren't doing this by dumb luck, everything is ironed out and works perfect.

Bret

Denny McLain

If they eyes are the windows to the sole, surely the dyno is the window to how the engine is performing. The way I look at it is the dyno gets ya on first base, track tuning gets ya to home base. They both work together and suspension tuning or gearing doesn't show on dyno's but hp sure does.

Every major professional motorsport uses dyno's and don't think for a second they don't. We were laughing today about all the claims the aftermarket mfg's used to make before there were dyno's to verify performance. JC Whitney powered!

Kearn

Bret,
Before you get too defensive, no where in this thread did I blame anyone or anything for my low numbers and it wasn't my intention to do so. I simply asked people's opinions and suggestions on why they think I got the results that I did. The first thing I'll do is check the knock sensor and scan my computer for knock. But until then if you or anyone else has any other suggestions I'd appreciate it. Thanks for your reply.

P.S. I have 2 new o2 sensors with extensions because of the long tubes.

SStrokerAce

No offense taken. Just posting for the masses ;-)

I'm sure you will be fine once the issues are worked out.

Bret

Denny McLain

Seriously, the 11.8 compression 385 combo with the same LE heads and GTP 6cam I sold to a friend in this post made below 400 rwhp when we first did the engine. It took us almost a year to figure out what the car wanted and when I posted it made 445 rwhp, no one believed it except a few of the hardcore guys who knew how to work out combinations.

There were all kinds of people saying BS who couldn’t get the hp out of their cars with the same stuff. But ya know what, have the dyno sheets to prove it and the guys who really know……..know it wasn't BS.

It’s all in the fine details, people with the experience/tenacity know what works or how to make it work and that separates the men and the boys. They guys making the big hp didn’t happen by accident. They are either a whole smarter than the rest of us or paid their dues. I believe it’s a bit of both and my hat’s are off to them.

Just added a sheetmetal intake and lost peak power on the top end but gained on bottom. Now if I was one of these “It should have made 25 hp more” I’d be awfully depressed. Down in the dumps, saying I was ripped off and telling people to never buy from these people.

The real issue is I need to make proven technology work for my application and not blame anyone except myself. After I find what cam the car wants, fully expect to make at least 500 rwhp using a hydraulic cam and standard port 23 degree heads. I drive a street car, not a track car and also fully expect very good drivability. But, that's for me to figure out.

The bottom line is Bret is right on, people with experience don’t expect miracles….they make them happen.

user 647483

Have you done any datalogging or tuning?
You'd me amazed what kind of things a short spreadsheet of numbers will tell you.

Kearn

Okay, I got my car on freescan and after startup it would show a little knock retard, up to 4. But after a couple minutes of driving it would stay at 0 until part/heavy throttle. Then it would go up to 1 or 2 then back to zero and stay at zero while coasting in neutral. Sometimes during party/heavy accel it would not show any knock retard. Did I find my problem? Does this seem like false knock to anyone or is it detonation? Also, if I want to test for false knock with 101 octane do I need to have a tune for 101 or am I okay with the tune I have? Thanks for all your help. Also one semi-unrelated question about freescan. My A/F ratio doesn't read, does anyone else have this problem and is there a way to fix it? Thanks again.

Kearn

Sweetred95ta

You don't need a different tune for 101 octane. You won't get a/f with Freescan or any other data logging system. You can log a/f with a wideband 02 setup. 1-2 degrees won't cause that much of a power loss.

turbo_Z

Could be a lot of things but Id check to see if the intake is sealed good from the inside. Also, get a real datalogger like Datamaster. If you can use freescan then you can use Datamaster and the first 20 scans is free... cant beat that and its infinitely more useful.

Did the car smoke on the dyno?

Are you sure the throttle was wide open?