Chevy Nova Forum banner

1 - 20 of 23 Posts

·
Registered
Joined
·
447 Posts
Discussion Starter #1
well got the tunnel ram on there got it jetted some what better than before and pv's should be in range. timing at 36. but its really lazy out of the hole, yes i know a tunnel ram robs bottom end but it should of made up for it on the top not so. i went from 12.50's last year to 13.60's WHOA:no::eek: i am not really mad at it. i just wanna know how to dial it in more. anybody got any advice?

302 chevy 13:1 compressing .536.557 cam 99* lobe center 295/287 <yes i know ****ty cam> 36* total

carbs dual 450's 66 jets in both 3.5 pv's in both 31 squirters.
 

·
Registered
Joined
·
4,612 Posts
u might

swap to 600 vs carbs , prolly be the quickest fix i'd say ,,, i saw 2 500 2 barrels do well on a 327 with 11-1 ,,, can't remember what his cam was

you might bump the timing up to 38-40 ,, what heads are u using ??
 

·
Premium Member
Joined
·
15,966 Posts
With the small CU

When I was class racing, we ran 38°-42° total timing and a high gear retard. to 34°

We did not have the luxury of digital boxes of today.
We ran a crank trigger with dual pickups.

36° total is not that great, you have a small cu engine.


Also, the air/fuel ratio at WOT throttle can easily be way off with dual carbs. Single carbs in most cases are very close on with AFR out the box. Dual carbs are easy rich. This is the area I would work on. Take the secondary jet size down 4 numbers. If you have access to a DYNO with a AFR pickup, would be a great investment. With the amount of CFM you have and a small CU engine, the engine could easy not use the total CFM, this is why the rich condition.




IMO
Al
 

·
Registered
Joined
·
447 Posts
Discussion Starter #4
i amr unning holley 450's mechanical secondaries single pump carbs. i cant afford to use 600's or i would have.

i understand the t-ram was going to rob alot of bottom but it never made up for it on the top either.

i was going to lock the distributor out at 38*

heads are "291" camel humps
 

·
Registered
Joined
·
136 Posts
You need to stahl it and give it a set of gears.I have a ram with 450's.4.86 gears and a 3800 stahl.Ran 11.4 at 129 mph and jumped out of the hole with a 1.4 60 footer.Also hava a set of 486 double humps
 

·
Registered
Joined
·
447 Posts
Discussion Starter #6
You need to stahl it and give it a set of gears.I have a ram with 450's.4.86 gears and a 3800 stahl.Ran 11.4 at 129 mph and jumped out of the hole with a 1.4 60 footer.Also hava a set of 486 double humps
ive got 4:88's and a 3500 stall! no t-brake tho.

have 5:13's on the shelf and a 4500

but i need to figure out why it runs like crap b4 i go changing a million things.
 

·
Registered
Joined
·
1,274 Posts
ive got 4:88's and a 3500 stall! no t-brake tho.

have 5:13's on the shelf and a 4500

but i need to figure out why it runs like crap b4 i go changing a million things.



Dang man your combo sounds a whole lot like ours except ours is a 355 backed by a 3000 stall, TH350 and 9" with 4.86 gears. We have never ran the car down the track and may never do so but it runs real strong. Strong enough to make me wonder what it would run. I know my stock 99 SS camaro will run 12.9 to 13.2 all day long and the nova feels much stronger than my SS.

The unilite in ours is locked out and set at 38* and runs real crisp. As far as the carbs go I have no clue what is in them. We got the whole setup from a friend that already had them dialed in to a combo very close to our engine and they worked great right off the bat.



http://www.youtube.com/watch?v=W9AmbTx1W0k
 

·
Registered
Joined
·
447 Posts
Discussion Starter #8
Dang man your combo sounds a whole lot like ours except ours is a 355 backed by a 3000 stall, TH350 and 9" with 4.86 gears. We have never ran the car down the track and may never do so but it runs real strong. Strong enough to make me wonder what it would run. I know my stock 99 SS camaro will run 12.9 to 13.2 all day long and the nova feels much stronger than my SS.

The unilite in ours is locked out and set at 38* and runs real crisp. As far as the carbs go I have no clue what is in them. We got the whole setup from a friend that already had them dialed in to a combo very close to our engine and they worked great right off the bat.



http://www.youtube.com/watch?v=W9AmbTx1W0k
the 38* of timing locked out is what i am hearing from almost everybody who is running or has ran a t-ram i will try that. i know the pro billet msd has a deal for locking it out.
 

·
Registered
Joined
·
1,274 Posts
the 38* of timing locked out is what i am hearing from almost everybody who is running or has ran a t-ram i will try that. i know the pro billet msd has a deal for locking it out.


Yeah give it a shot. It certainly wont hurt anything. Might make the engine turn over a little slower but thats about it. Good luck and keep us updated. Not many T-Ram guys now days. They look cool and if set right they run exceptionally well.
 

·
Registered
Joined
·
1,040 Posts
FIRST , you are jetted beyond your needs . Stock jets are 58 front and a plate in the rear . I had a 57 chevy 4 door , HEAVY FULL STEEL CAR , i ran 3.36 gears a 3500 converter ,street tires , a 12.1 compression 350 , a compcam 280 magnum flatt tappet cam 450 carbs ,and fuelies . this car would run 12.9 at 110 mph.
I ended up running 60 jets in front and never touched the secondary plate . I also used 2.5 powervalves. The squirters were like #47 .... The worst problem i had was LEAN bog out of the hole . The 47 nozzles almost cured it though !
I would say drop jets to 58 again and run it . See if you mph faster . If so drop them again ,and repeat .

Oh i also ran timing unlocked , Im sure it would have cured alot of my bog with it locked .
This engine would also pull 6900 rpm , NO problem .That was the shift point it liked . And i woould have never guessed that little cam could rev like that !
 

·
Premium Member
Joined
·
15,966 Posts
Just a thought.

Have you pulled a plug and looked at it?

This could tell you a lot of info.

Also are you running a med to hot heat range?

Al
 

·
Registered
Joined
·
3,601 Posts
If you lock out the timing I would suggest adding a switch to the ignition circuit. Then you can get the engine rolling over before the ignition comes on. It's a lot kinder on the starter motor.
 

·
Registered
Joined
·
2,146 Posts
do you drive this car at all on the street? I would plug the PV's off and jet accordingly. I never run PV's in any carb I use at the track. If its a street/strip deal then I run one in the front. Maybe start off with 59 squared on a fresh set of plugs and pull one on each side front and back. Jet accordingly and watch mph if it goes up your on the right track. Definitely need more stall too. Zing that little 302!!!
 

·
Registered
Joined
·
309 Posts
If you lock out the timing I would suggest adding a switch to the ignition circuit. Then you can get the engine rolling over before the ignition comes on. It's a lot kinder on the starter motor."X2,,, thats a lesson I learned on my first 64with afaulty ignition switch
 

·
Registered
Joined
·
4,612 Posts
put the good stuff

in there , i'd get the car and transmission as good as i could to work with the motor.

There was a thread on here where someone added they converted the 450's to vacume secondarys and 4 corner idle and it really helped his car.

These carbs are of the 4160 variety without a secondary metering block so it just makes for a difficult combination to really nail down with the carbs stock. I think Holley should be forced to do a recall and put the secondary pump on them and metering block ,,lol. I don't even think there is a boss to add a secondary squirter either.

Back years ago , there used to be a 1-1 conversion kit that had a squirter with a tube that would reach over to the secondarys for some pump shot.

These just aren't the easiest carbs to use that will get the best time out of a car
 

·
Registered
Joined
·
447 Posts
Discussion Starter #18
i understand that and if ic ould buy somehting else i would , carb wise.

i ahve an msd controllable advance-retard box inside the car i cand ial down when starting not a problem.

i ahve found this motor likes to be shifted at about 72-7300 no more no less. its the cam thats in it. itll be changed out soon.

after re-jet at the track to 66's that was the last run. also fromt he 72's and 76's the plugs were ruined ill let you know after i get another set of plugs i run cold plugs 84 or 85 autolite standards.
 

·
Registered
Joined
·
347 Posts
I was considering a tunnel ram setup, for the looks. I'm not going to race hardly anymore at all. This car is for fun first! I can't afford a blower motor at the moment, and probly won't be able to for a long time. but I've always, really liked the look of the hilborn style scoop, peeking out of the 4" cowl hoods. I've got plans on days that it may be wet, so I'll have that taken care of, or I'll just borrow the wife's truck lol.

Not trying to hijack. My question to the OP is, is your tunnel ram setup having that much trouble? or is it just not fast as it should be? I'm not a tuner, never have been> i can assemble a hek of an engine, but tuning was never my thing.

I had thought about that kit from jegs with the 450's. I only have flat top pistons with the Dbl humps that I think have the 64? cc heads. Not sure my comp. ratio, but you are talking about a lot more compression than I'd like to run, is it necessary on your tram setup?
 

·
Registered
Joined
·
447 Posts
Discussion Starter #20
that has always been my problem, i can put it together nice but i cant tune it for beans!:no:
 
1 - 20 of 23 Posts
Top