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AFB gurus for a 528 hemi build

Posted By: fig426

AFB gurus for a 528 hemi build - 07/22/10 12:23 PM

I'm almost done with the 528 hemi build. It's 10:4 comprssion, 295, 630 lift cam, 4000 stall,727 foot brake, 430 gear, 3900 lbs, 29" tires. Strip only car. I'm using dual factory 1970 hemi AFB's. Any suggestions for a baseline on the carbs?

Attached picture 6098923-3721402-ChallengerHemi1.jpg
Posted By: Cudajon

Re: AFB gurus for a 528 hemi build - 07/22/10 05:38 PM

One persons absolute greatest baseline can be anothers POS. But here is what I had. Primary carb. Primary jets. .95 second 86. orange springs in the metering rods .071 X .047 metering rods accel pump in first hole next to carb (max shot at hit of throttle) .110 needle and seat. Secondary carb .98 primary jets .89 second orange springs .0705 X .0475 rods accel pump in middle hole .110 needle and seat. HOWEVER, if you are not running progressive linkage I don't know where to go.
Posted By: fig426

Re: AFB gurus for a 528 hemi build - 07/24/10 03:31 PM

Thanks Cudajon. Any other suggestions?
Posted By: Anonymous

Re: AFB gurus for a 528 hemi build - 07/24/10 03:54 PM

which intake are you using, think that jetting will be way too lean for your combo.
Posted By: fig426

Re: AFB gurus for a 528 hemi build - 07/25/10 12:39 PM

Quote:

which intake are you using, think that jetting will be way too lean for your combo.


Factory 70 aluminum inline dual 4 with the plenums and ports opened up.
Posted By: scatpacktom

Re: AFB gurus for a 528 hemi build - 07/25/10 02:51 PM

I would inquire with Dave Dudek if I were you. He has a pretty good grasp on jetting a hemi that has had its intake monkied with
Posted By: fig426

Re: AFB gurus for a 528 hemi build - 08/25/11 04:53 PM

I talked to Dave a while ago and he didn't have any similar setups. Super nice guy though. Anyone else running a similar combo? I'm running pump 93 (10% alcohol) and having trouble reading the plugs. I have in what Cudajon put up. Best so far is 11.44 at 115 mph. 1.577 60 foot. Caltracs, monoleaf, rancho shocks on 7. Shifting at 6000, going through the traps at 5900. 3900lbs with me in it (estimate).

Attached picture 6794480-0805111526.jpg
Posted By: Cudajon

Re: AFB gurus for a 528 hemi build - 08/25/11 06:01 PM

I failed to mention I run an Autometer O2 gage in my car set to record the AFR on runs. It sure helps tweeking the AFR. 11.44 aint bad for a 2 ton car. But I think your mph is low; however if 6k is the rpm goal and your trapping at 5900 you don't have a lot of leighway there.
Posted By: fig426

Re: AFB gurus for a 528 hemi build - 08/25/11 08:49 PM

6k isn't really the goal, it's just where I have been shifting at. The rev limiter is set at 7000 and I've hit that in the burnout box. It sounded good up to the limiter. I'll shift higher or lower, but I need to get some more fuel in it so I was wondering if anyone else had a similar setup and what their jetting is. Your jetting got me up and running but it's definately lean in my setup.
Posted By: Cudajon

Re: AFB gurus for a 528 hemi build - 08/26/11 01:27 AM

OK great. Change the metering rods to something smaller. Its easy and quick. If the et or mph improves your going the right way. Dont worry about the springs at wot there not doing anything. If the et picks up then change the jets a couple of sizes richer. I normally rejet the secondary carb first and see what happens. The primary carb if its too rich will cause a stumble. If the secondary handles it ok then do the primary. My HEMI really liked to be lean, I was always amazed that the tailpipes were a very light gray. 11.94 @ 119. 3:55 gears 68 RR. .30 over 426. I was happy.
Posted By: cgall

Re: AFB gurus for a 528 hemi build - 08/27/11 07:16 PM

Fig, Dirk Hale is a wizard with those. RBDuster should have his number.
Posted By: Cab_Burge

Re: AFB gurus for a 528 hemi build - 08/28/11 04:34 AM

Quote:

Quote:

which intake are you using, think that jetting will be way too lean for your combo.


Factory 70 aluminum inline dual 4 with the plenums and ports opened up.

Can you post a picture of the intake with the mods? I use to run stock street hemi years ago, maybe the jetting we used might give you a good place to start with I do know another NHRA racer that has ran the street Hemi in stock and SS that has set the record once or twice with his car, maybe he will share if I call him Post a picture and let see how it is modded Or send it9the picture) to my E mail address cabburge@wans.net
Posted By: Cudajon

Re: AFB gurus for a 528 hemi build - 08/28/11 04:41 PM

You say the intake has been opened up. Is it the Vanke mod? Seems they liked a 1" carb spacer to really pick up. Of course hood clearance was an issue but most had hood scoops.
Posted By: fig426

Re: AFB gurus for a 528 hemi build - 08/29/11 01:47 AM

I don't have a pic, but it is the Vanke mod and gasket matched. I'll have to see if I have room for spacers.
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