Has anyone ever used holley adjusta-a-jet metering blocks?

[Shawn MacAnanny]

I came across these they seem like a pretty good idea since i have a dual wideband setup.

http://www.who-sells-it.com/images/c...ion-000085.jpg

[oestek]

Jeff Schwartz swears by these things. I have not tried them yet, but it is a good idea. PM or email Jeff and he'll tell you all kinds of tuning stories about the adjust-a-jets solved problems.

[Shawn MacAnanny]

I guess his name isnt his username it couldnt find him. Here is the email i was going to send to him i am not sure how to contact him.

I made a post about using them and i was told to PM you because you know alot about them. I am looking at a set someone has for sale for primaries and secondaries and i wanted to install them on my 3310 4160 carb. I have already converted it to a metering block and have 72 primaries, 76 secondaries, and a 6.5 power valve. I also installed a 50cc accelerator pump and the car is completely rebuilt.

I am also running a Fast dual wideband 02 system that logs AF so i thought these would be a great idea for tuning my carb. Right now it's a lil richer than id like it to be (12.8 @ WOT i want around 13.5) and around 13.6 at cruise (i want around 15)

I have been reading up on them and i see i ned a transfer tube to use them on a 4160 carb but will i still need that if i am running a secondary metering block? Any info on these would be great as i just found out about them a couple days ago and i really think they would work well for me.

Thanks!
Shawn

[oestek]

Try contacting him through their site: http://schwartzperformance.com/

[Shawn MacAnanny]

Thank you! after looking at his site if he swears by them im buying them haha. They seem to me like an awesome idea and would make jetting the carb for even easier for me sice im running a wideband.

[Shawn MacAnanny]

I ended up buying them for the secondary and primary jets. they work GREAT! i have everything but a 2000-2500 rpm 1/8 throttle or less lean stumble tuned out with the carburetor and these things are great for making adjustments on the fly to get my AFR where i want it.

[Shaker455]

I am also running a Fast dual wideband 02 system that logs AF so i thought these would be a great idea for tuning my carb. Right now it's a lil richer than id like it to be (12.8 @ WOT i want around 13.5) and around 13.6 at cruise (i want around 15)

Thanks!
Shawn

Shawn,
12.5 is where you need to be @ WOT.

Also if you car bucks @ 15 that means it too lean and if you look at your FAST landscape chart you'll see that the top of the limit.

[darkostoj]

the main jets aren't going to have anything to do with cruise..that is if the rpm is lower. Main jets dont get activated until around 2500rpm depending on the booster type

[Shaker455]

the main jets aren't going to have anything to do with cruise..that is if the rpm is lower. Main jets dont get activated until around 2500rpm depending on the booster type

That is not correct,

The main jets have a direct impact on the ratio of fuel vs air and will have an effect on every circuit.

[68Formula]

the main jets aren't going to have anything to do with cruise..that is if the rpm is lower. Main jets dont get activated until around 2500rpm depending on the booster type

I've found the main jets affect the a/f as low as 2000rpm. And that was with the crappy straight leg boosters. I didn't test between 1000rpm and 200rpm, so it could be less. At 1000rpm (basically idling in drive with car moving) only the idle mixture screws were affecting the a/f.

[Shawn MacAnanny]

Well I'm taking the car to dyno tune here in the next week or so, so i'll have them log my AFR with my wide band and adjust the jetting and timing as it makes power.

[Skip Fix]

Your idle setting also affects the cruise AFR and can up to 2500 sometimes. So alot of circuits all work together there.

[Shawn MacAnanny]

Well im having alot of trouble with my carb now. It running really lean on start up which is normal runs and idles fine at like 14:1 or so but then when i get cruising and engine is too temperatue it idles at like 12:1 and cruises at as rich as 10:1. Its really frustrating me. I'm considering pulling the adjust a jets off as i dont remember having this tuning being so tempermental before.

[Shaker455]

Shawn,
I hope your running a good in-line filter like a Jegs or Summit brand right up by the carb that filters 10 microns....otherwise your most likely filling the carb with dirt.

Also with the units I've built I've provided custom screw-in jets for the transition circuit to balance the A/F.

I've built a few for Skip in the past so maybe he'll chime in on his results?

[Shawn MacAnanny]

Oh really? I run a clear glass filter before the pump by the tank. The tank, sending unit, fuel pump, fuel line are all new and i just rebuilt the car a little while ago. So i should be running a filter after my pump before the carb?

[Shaker455]

Shawn,
Espically if you fuel system is new as pieces of cut line fragment into the carb as well as other material.

If your running an elec pump you should have a pre-filter that does 100 microns then one up by the carb that does 10 microns.

I had one of those glass deals on my Camaro back in the 80's and it's just a screen...not good!

[Shawn MacAnanny]

Haha well i will get another filter then. I think i still may just got an install my regular jets in my carb.