Stock Holley 750 DP Jet size?
#2
Supreme Member
Join Date: Jan 2000
Location: Panama City Beach,Florida
Posts: 1,301
Likes: 0
Received 1 Like
on
1 Post
Car: 1989 Camaro
Engine: 406
Transmission: Pro-built 700R4
Holleys all came with different size jets. The only way to find out what the stock jetting on your carb is supposed to be is to get the numbers of the coke horn. If you post the numbers I will tell you what size the stock jetting was in it. Or you could start backing down two jet sizes at a time till the engine stumbles then got back up a size.
#4
Supreme Member
Try 70 primary and 80 sec (without sec. power valve)
or 76 (with sec power valve)
This is normal jetting for a 750 DP carb.
Be sure your "rich mixture" is not in the idle circuit which has nothing to do with the main jets.
Check that your power valve has a vacuum rating that will alow it to remain closed at idle. (in gear).
or 76 (with sec power valve)
This is normal jetting for a 750 DP carb.
Be sure your "rich mixture" is not in the idle circuit which has nothing to do with the main jets.
Check that your power valve has a vacuum rating that will alow it to remain closed at idle. (in gear).
#5
Moderator
iTrader: (14)
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 43,169
Likes: 0
Received 35 Likes
on
34 Posts
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Get the Holley jet assortment kit from Summit or Jegs - about $35. It will have a pair of everything from 66 to 99 (I think that's the range, anyway). Then, when you pull the bowl off, look what's in there, get a set 2 below that (as stated above), and go from there.
The assortment kit will cost you less than buying jets in pairs by the time you find your right ratio. And, you'll never have to buy another jet.
The assortment kit will cost you less than buying jets in pairs by the time you find your right ratio. And, you'll never have to buy another jet.
#6
Supreme Member
Thread Starter
Join Date: Jun 2001
Location: Indianapolis IN
Posts: 1,522
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the help. I finally bought my daily driver ('88 Turbo Coupe), so I can start tearing into the beast. I'm going to port/polish the heads since they are in desperate need of it and then see how she goes. I was runnig Friday night and the temp probably got down to high 60s F. The cooler it got the better she ran. By the time I parked it it was running 5 in. Hg. more vacuum at idle than usual. I'll have to check on that power valve vacuum thing. Also I have another question. I can't seem to get it to idle down when I have the vacuum advance on the dist. connected. It idles around 1000. The throttle screw isn't touching the linkage, and I have the idle circuit adjusted right. The linkage isn't sticking either. I was wondering if anyone else had these problems. Like I said though, I'm going to be tearing into it, so this might all go away when I put it back together. All I have to do now is shell out $90 for an electric grinder. Stupid compressor isn't big enough.
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post
toronto formula
Engine/Drivetrain/Suspension Parts for Sale
15
11-10-2015 06:17 AM
knight72
Engine/Drivetrain/Suspension Wanted
0
08-10-2015 09:32 PM