Re: H-I-J '76 Nova re-fit.
 

I have an Innovate Motorsports air/fuel recorder that activates off a short to ground momentary button like your setup. It's very sensitive to power interruptions. If I forget to shut the SD recorder off by hand and kill the engine it will dump all data from that run. Killing the engine at the stripe might be corrupting your data.


Have you been able to get a readable file at idle in the shop?

Re: H-I-J '76 Nova re-fit.
 

Todd-- look at the video --the launch RPM appears to be about 62-6300----- is that low ?? 1-2 shift was 72-7300 did she nose over or over rev the engine???-----2-3 shift is about 66-6700 is this too low???--------3-4 shift is again low in the 6600 range--- do you agree ??? Not sure what racepak is showing but the shift points are all over the place that might be what is giving you goofy ET's.---you have a fairly heavy car with a low HP engine and once you run out of gear going into high gear it just does not have enough power to recover and produce a real good ET.----Not being overly critical but the driver must aim for consistent shift points ---are your RPM shift points in the correct range not too high or not too low???---what is your finish line RPM it seems to be fairly low shouldn't it be in a higher range looks like low 6200-6300 range???--just my observations from the video----FED 387

Re: H-I-J '76 Nova re-fit.
 

It's because the clutch is slipping..It's not climbing and dropping in the gears.Probably toast by now. Also the wing, wing, wing and dump on the up throttle is hard on the clutch. Need to have enough clutch for 3rd gear burnout, without going to 7000 grand! ...and hold it there for a second, then drive out as the tires dry. IMO

Re: H-I-J '76 Nova re-fit.
 

Just going off the online Wallace calculators.

Your ET / MPH computed from your vehicle weight of 3400 pounds and HP of 390 is 11.99 seconds and MPH of 112.73 MPH. That's optimistic IMHO....The car did go 12.0 something so its not far off.....Don't know the MPH on that 12.0 run......MPH indicates HP better than ET....


11.99 x 112.73 =1351 and that is very high of a factor number for a limited cyl head type stocker...…..They are usually weak on MPH with fast ET's due to gearing. Your biggest ET gain is in the first part of the run with a Stocker...


Just yesterday at Maple Grove some H/SA cars were running 11.0's......at about 116 we'll say......11.09 x 116.7 I think I saw....do the math...thats1294...…..Very fast ET......not a lot of MPH....not sure if that was flat down on it......maybe off one or two MPH's at most...…. A Low compression 350...


I did not think the run sounded like the clutch was slipping badly at all....
RPM did not flair.....engine was weak and rpm did not climb....


Its been way to many years since I had a stick shift car. We had no rev limiters, just picked an RPM and held it there......


Most stick racers I watch put it to the mat on the first or second amber and on a chip...…


She's doing a pretty good job and just needs more laps......and some tuning to get the most out of what's there....It's Way harder than driving an automatic.....

Re: H-I-J '76 Nova re-fit.
 

Only by hitting record in the program.

Re: H-I-J '76 Nova re-fit.
 

I lowered the launch rpm to 5800-6100, 6500 would be typical, we're just trying stuff. Optimum shift point will probabbly be between 7000-7100, shift light is at 6500 because I know she won't hit every shift. Not sure about the goofy ET comment, we made 3 runs without changing the launch rpm and the cars ET varied .017 and the 60's varied .011 WITH us changing other stuff on the car. Yes, she isn't hitting the shifts perfectly but I would also like to point out she is also NOT shifting clutchless per se. Correct, the car is not pulling in high gear and we have to work on the setup for that.

Re: H-I-J '76 Nova re-fit.
 

If you have a trusted line lock or transbrake button to spare, wire it in place of the factory button to eliminate a failed switch as the issue.
If that still fails, wire a switch to the alternate contacts mentioned in the manual. It's possible the factory trigger circuit (blue button circuit) is faulty in the box.


EDIT: BTW, that switch is a $13 part.

Re: H-I-J '76 Nova re-fit.
 

Mark, by an outsiders obsevation it seems you're quite a revered member of this site, with that being said, maybe you shouldn't comment about things that may derate your classracer social status. In other words, everything you said is wrong.

Re: H-I-J '76 Nova re-fit.
 

FWIW,seeing you only made 1/8 mi. passes going by Wallace calc.your 1/8 et (7.27) and (93.50) mph says your 1/4 should be 11.55 at 115 which seems reasonable.That would be a big jump from Indy!...gsa612

Re: H-I-J '76 Nova re-fit.
 

This is exactly right, the clutch only seems a little light at the hit, which, as you mentioned the lower starting line rpm will have a hand in slippage running a counter weighted setup.


Here's the Waller 1/8 mile calculation, remember we only ran it just past the 1/8th.
https://i.imgur.com/N7HcoKXh.jpg

Re: H-I-J '76 Nova re-fit.
 

I'll have it out to work at it later this week.

Re: H-I-J '76 Nova re-fit.
 

Hey Todd. Watched the in car video and Autumn did everything right including the burnout. The burnout you can do in 2nd or 3rd. Doesn't matter. I've made enough runs on mine to know missing a shift point (which I've done lots LOL) unless you hit the limiter will maybe affect ET a few hundredths. She's doing good and will get better and more comfortable with seat time. Getting a clutch to be perfect can be tough. Once you get the racepak working it will be an amazing tool to make sure the clutch is working as it should. Have enjoyed following the build of the Nova.

Re: H-I-J '76 Nova re-fit.
 

That's basically what I came up with, and the DA was 2800'. I'm pretty sure there's another .10+ in tuning and a gear swap, I'm ok with that for a start.

Re: H-I-J '76 Nova re-fit.
 

Thanks Bob, we run a heavily counter weighted setup, it will drive right through the clutch hitting it from 2500 rpm. Tinzy called me today and said her and Cale are coming to see us in 2 weeks so I'll have the clutch guru's here and I'll get even more knowledge and inspiration from the folks at Black Magic!

Re: H-I-J '76 Nova re-fit.
 

If you ran those numbers in a 1/4 mile run You’d have to be real happy. I would be.

I wired the stock horn button to work the line lock on our ‘68 Nova back in 1969.

That car had a built in rev limiter. It would just go flat at 6000 or less with what we had to work with back then...Some cams pulled up a little higher at 6200.....Hydraulic lifters, stock springs, stock rockers. 12.20’s at 114+ was best numbers back in 1970 on 7” tires ! 10-1 compression 350...


The clutch was low tech. Schiefer RevLoc diaphragm clutch, 10-1/2” GM disc 11” 30lb wheel.

Re: H-I-J '76 Nova re-fit.
 

Kinda wonder who I'm discussing this with now.

So, okay ,if you think 7000, make that 7500 on the burnout is necessary and good for the valve springs, etc. , is the right thing to do, and I'm wrong, then tell Autumn to keep doing it..By all means
;-)

Re: H-I-J '76 Nova re-fit.
 

I'm honestly amazed after the dyno runs and where the power was, how far this thing will rev, in lower gears it will hit 7500 no problem.

Re: H-I-J '76 Nova re-fit.
 

60' is off, needs some clutch at the hit. If you dump the clutch at 5k the wet tires won't turn a lick, low base all counter. The only reason it stopped at 7500 is because thats where the chip is, were here to run heads up and haul *****, if we have to turn it 8k and buy valve springs, we'll throw a couple sets in the trailer or we'll fix it when it snaps something off. How's that saying go? We're here to chew bubblegum and break valve springs and we're all out of bubblegum!

Re: H-I-J '76 Nova re-fit.
 

Okay, I understand the low base /counterweight thing. Better use 2nd gear then.
Forgive me, guys.
Carry on..

Re: H-I-J '76 Nova re-fit.
 

It's all good!

Re: H-I-J '76 Nova re-fit.
 

A stock Z/28 302 would rev to 8000 if you let it back in 1969-1970

I drove one and that’s with stamped rockers and springs that had about 100lbs on the seat IIRC..

The difference from a hydraulic cam engine to a solid cam was like night and day.

Re: H-I-J '76 Nova re-fit.
 

My friend Joe Demarzo making a real nice pass this past Sunday at MG



https://www.facebook.com/larry.guest...4756815921752/

Re: H-I-J '76 Nova re-fit.
 

Absolutely

Re: H-I-J '76 Nova re-fit.
 

If hitting the clutch hard in the water is wrong then we have been wrong -- a lot! LOL With today's valve springs and the better control of the valve versus the 'old days' I would just make sure you have enough piston to valve clearance and let it rev. Hitting the shift points will come with seat time. We set our shift light below where we expect to hit it on the Racepak just like you do. After a couple of laps in the Spring we are able to adjust them to be a little closer.

https://youtu.be/AOM7ut3xWLQ

Re: H-I-J '76 Nova re-fit.
 

This Chevy II is one of my favorites! Joe, we added .015 on the head gasket and have lots of ptv just for these conditions.

Re: H-I-J '76 Nova re-fit.
 

Loaded up and headed out to VMP this afternoon... pics and vids to follow.

Re: H-I-J '76 Nova re-fit.
 

Temps tomorrow and Thursday in the upper 90’s. Going to feel like you’re still in Florida.
Drastic change for race day Lol should be fun!

Re: H-I-J '76 Nova re-fit.
 

This is my favorite in car video of the Nova 283 and some extra clutch for the dry hop!

https://m.youtube.com/watch?v=-xHXjTQWxwM

Re: H-I-J '76 Nova re-fit.
 

My favorite
https://youtu.be/EyksWlC-HFo

Re: H-I-J '76 Nova re-fit.
 

Looked like that could've hurt.

Re: H-I-J '76 Nova re-fit.
 

Please tell that to NHRA, the solid lifter engines were penalized with HP from the factory and now that all the hydraulic engines can use solid lifters they didn't get HP. But the solid lifter engines didn't get a reprieve of HP.
Casey Miles
Stock

Re: H-I-J '76 Nova re-fit.
 

1970 LT1 , 360 hp, now 320 with manual trans. ;-)

Re: H-I-J '76 Nova re-fit.
 

Really really hot here at VMP, made a clutch adjustment and two test runs today. About .05-.07 slower than our test last week but Good weather is on the way. Too hot so I'm going in the a/c for a bit then doing carb work tonight. Shot an in car video and you can clearly hear the car labor in high gear till maybe 6100 then takes right off till about 6900 at the finish. Making some shift light adjustments for tomorrow.
https://i.imgur.com/RcBZsDih.jpg

Re: H-I-J '76 Nova re-fit.
 

1967-69 Z/28 302, 290 HP from factory, 309 NHRA Factor. That same 350 that you mentioned, only has to weigh only 110 lbs. more than the 302 in E/S. The 302 is factored to 1.023 HP per ci, the 350 since it's basically the same engine just more cubic inches should have the HP factor of 358 HP fallowing the same formula. NHRA gave that engine combo a gift.
Casey Miles
Stock

Re: H-I-J '76 Nova re-fit.
 

The LT-1 is indeed a Big cube Z/28.

My friend had a 70 Yenko Deuce and it was a very fast car.

Engine broke a rod and I put a Z race engine in the Deuce. That friend had a ‘69 Z racecar. I made some runs in that one. The Deuce was still very fast with the 302 in it, Street car with very steep rear gears.

Those 2 cars were probably my favorite cars I’ve ever driven.

The 69 Z would be worth a fortune today. Who knew !! 😂

Re: H-I-J '76 Nova re-fit.
 

That’s awesome ! That dyno you tested the engine on must be awfully stingy on readings or something changed a lot. Those engines generally pick up a lot in good air. Good job !

Re: H-I-J '76 Nova re-fit.
 

if stockers are out first tomorrow 9:00 am ,that et will be quicker ,get your race pack ready to log those O2's
your getting there ,, I need to find more as well ,,I will be watch d1tv

Re: H-I-J '76 Nova re-fit.
 

Yes, I was told the dyno was not a hero machine.

Re: H-I-J '76 Nova re-fit.
 

I'll assume the air will be better here on out, I don't know about the car but I know I'll feel much better about it.

Re: H-I-J '76 Nova re-fit.
 

What weight do you run at?