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Paint Codes





   I read your article on the truck avenger and was glad to hear you have yours running well.  Mine is giving me fits.   I have a 302 with roller cam in my bronco so I figure we are fairly close in application.   Mine is running very rich I think, at first it was barely drivable so I called Holley and they said that there had been an engineering revision and switched from a 6.5 power valve to a 2.5.  I did that and it helped a lot.  Now I’m trying jetting.  I dropped 2 on the primary and that seemed to help some.  It also doesn’t idle very smoothly and the idle mixture screws don’t have much effect.  Too much of the idle transfer slot is expo's ed so I was thinking of opening up the secondaries slightly to hopefully get the idle slot back. 


   Do you happen to know which power valve you have? 


Thanks for any suggestions you can offer,


When I got my Truck Avenger and “out of boxed” it, it ran so rich I thought I was going to see gas trickling out the exhaust pipes!


This is the first I have heard of a revision to the pump valve. I will defiantly be calling Holley – today. Every Holley I have ever owned was an unstable idling, cold-blooded, rich burning, gas hog right down to the one-barrel carbs. If Holley recommends 2 steps leaner go 3, if you removed that EGR and plugged the holes in the heads – go one or two steps leaner.


On the Holley’s the air mixture screws do not really affect the idle much just the overall performance. Go 1 ¼ turns out and forget them.


I assume you have already checked for vacuum leaks… Correct? If not, here is a little trick to use… instead of listening to your intake manifold or doing the extensive leak down test here is a quick tattletale start your engine use a vacuum gauge on your intake vacuum port, (Located underneath the left side of the front fuel bowl next to the PCV port… another conveniently placed item) if you don’t get a rock steady reading you have a leak somewhere. . Find it , fix it.


As far as the idle goes, the curb-idle screw and the choke duration are the only “quick fixes”. The fast idle screw does not help much at all, as you increase it generally you loose your curb idle control. The secondary idle is your key to choke and idle mixtures, that is why they hide it so well, don’t talk much about it and put it where you practically have to pull the carb to adjust it. I think they are still looking out for Earl at the local garage while targeting us of all people as buyers… I will be adding some adjustment tricks, pictures soon for adjusting Holley's "on the block".


Anyway, use a small ratcheting right angle screwdriver or a very small ¼ ratchet with a bit for on engine adjustment. Chilton’s says back it off until it closes and then open or tighten it up ¼ turn Holley’s manual says 1 full turn the adjustment is actually somewhere in-between.


 I read your Holley vs. Edelbrock page. I was considering putting a Holley Tr. Aven. carb in my '74 Bronco w/ a recently rebuilt 302.

Are you still using the Holley?
How does it run?
Do you do a lot of 4-wheeling?
They (Holley) talk about the angles of driving and the carb not flooding, have you found that to be true?
What intake manifold did you use? Mine is stock.

Thanks for the info,

Yep, still using it.


It seems to perform well, however, if you built your 302 stock and are using a stock intake you might want to consider a Holley 500cfm 2300 Race series Summit Racing it will run rings around the avenger for a stock setup. I have the marine 500cfm on my boat with a V6 and I can accelerate right along side my friends with dual 454’s fully blown. Although they pull away above 40mph, this still gets on their nerves.


Otherwise, if you want to go with the Avenger put it on a Wieand Stealth intake and install an H-pipe on your duel exhaust. Otherwise, you will be fighting the fact that you are over-carbureted forever.





I came across your website comparing the Edelbrock carb and Holley carb.  I have the exact Edelbrock carb that you have on a small block Chevy 283 in an El Camino.  I absolutely CAN NOT get it to accelerate properly.  I’ll hit the gas and it will be “dumb” for a second then take off fine.  I figured it was because it was running too rich.  So I used the chart in the Edelbrock manual and set it up to be number 7 which made it leaner in the cruise mode and power mode, but it is still doggish.  Sometimes if I don’t back off when it bogs, I’ll even get a backfire L  It really baffles me since it has great response if I’m just revving the motor and not moving, but really poor while in gear.  I was just wondering if you had encountered any similar problems or know of anything that I could try to stop this madness.


Yes, I saw that exact problem for almost 2 years. The two solutions I found are

One – step up the idle (not what you want to hear) 

Two put a spark advance delay on the distributor vacuum line (better idea). If you have one already, put a longer delayed one on. As far as I could tell, the delay came from the initial air dump before the needles can react from the lack of intake vacuum.


Hope this helps…



Hi, I was just reading on your website about your Holley vs. Edelbrock opinion and i have a Edelbrock performer series 600 cfm 4barrel carb on my 73 bronco.  i bought this bronco like a year and a half ago and don't know anything about carb's.  i drove as a daily driver for a year and the carb drove me nuts to say the least.  I don't know what the problem is exactly but as of now i just replaced the fuel filter to see if that was the issue without any luck.  Anyway what it does is bogs down when light to mild gas is given to it and sometimes gives a pop and dies and other times just shuts down.  It also occasionally does this when a lot of gas is given.  You can never tell and that isn't very comforting when pulling into traffic.  It seems to run ok when i get up to speed but if I have to stop and go again or even slow down to a low speed to pick up again this seems to happen.  Do you know if it is running rich or lean or if this is the problem.  Any help you can give me with this would be great.  I am trying to pin point this problem so i can at least drive it for fun.  Also if you think this is the problem do you know how to tune a carb.  I've been searching on the net on how to do so but its very hard to understand and like I said I don't know anything about carbs.  I've done some work to my bronco with electrical and some other stuff but have very limited experience with engines.  Thanks for your time.


Just from hearing your problems below, it sounds as if maybe you have more than just carburetion problems. To me it sounds as if you may need to look at your timing (to far advanced possibly). If you have checked that and verified it is set at 8deg BTC (before top dead center). Then check for vacuum leaks I have found that a $45 “Mighty Vac - Summit Racing or JC Whitney” is more than worth the investment. Take a close look at your vacuum advance on the distributor for leaks (usually compensated for by advancing the curb idle or timing).


All that checked out and/or corrected, next move to the carburetor. Verify that the distributor advance is connected to the right port. On a Ford, this is the port on the passenger side of the carburetor.


Next, make sure your choke (if electric) is hooked to a keyed positive power source not the alternator as your original was. This is especially important on the Edelbrock carburetor.


If all of that checks out, you should be having far less problems with the “popping” and “dieing” now. Next it’s time to address the low end bogging:


The things that come into play here is;

1.      Carburetor

2.      Air cleaner

3.      Intake manifold

4.      Exhaust system

5.      Camshaft (I will skip this because it is beyond the home tuner scope)


Ok, before we go further, I will assume that you have a stock intake manifold with, “I hope”, a duel exhaust system consisting of at least 2” ID pipes.

If this is not the case, you will have continued problems with low end bogging because basically, a 600cfm carburetor is over-carbureting your stock setup to far. In fact, 600 cubic feet per minute is over-carbureting any 302 except one built for drag racing. This does not mean through it away….


Now, to make your Edelbrock run;


Use as large an air cleaner as you can. I recommend a 14”x3”. Use a drop type for clearance $14.00 Pep Boys with a 1” riser to clear your choke.


Ok now you have covered air before it comes in and after it goes out. Next;


On the Edelbrock one thing I noticed was the tendency for the air/fuel idle mixture screws to vibrate out over a period of a week or two "of course at different rates". I solved this using two plastic caps from TV coaxial connectors. Any plastic caps that will fit tightly when pressed on will work. I drilled small holes in the edges of the caps and wired them together so the screws could not vibrate out. I plan to add pictures and a short “how to” on my site soon.


Another quick trick for the Edelbrock is to add a vacuum delay on your distributor advance. Again, I will be adding this as tips and tricks on my site soon.


Next, do not be afraid to lien that carb out. You are over carbureted so you need more air and less gasoline, jet it down using the documentation that came with your carb or download the manual from the link on my page or at . Go one level leaner than they recommend if you are using the stock intake. 2-3 levels leaner if you removed the EGR and air pump system and plugged the holes.


The biggest low end improvement for your truck will come from your exhaust; lets assume you already have long-pipe headers, duel exhaust and free flowing mufflers like glass packs or turbo mufflers and you want a huge increase in your low-end… install an H-pipe. It is that simple. An H-pipe is a crossover pipe installed after the headers and before the muffler. This simple adjustment will give you gobs of torque you will burn rubber with mudders off the line. Summit Racing sells kits. Please note this is more than likely (Not street legal) as with various other improvements I mentioned above.


I hope this helps let me know how it goes…

Paint Codes:

Mike: here are some pictures of the interior paint... we are still going to bed-line the entire inside of the Bronco... the exterior paint will be done sometime around Christmas or the first part of 2005... this has definitely been a project... I had our local NAPA store mix the paint code you suggested... it turned out a straight RED... so they mixed up competition Orange and it was a nice match to what my original interior was... so this is what we went with...

Glenn, being that I'm not a NAPA fan as of recently, I'm can't say I'm totally surprised at the paint mismatch. I recommend that people go to a Sherwin Williams or a commercial auto body supply company to get your paint... Did they at least give you Acrylic Enamel or at least Enamel? If they gave you Lacquer of any kind... see if you can take it back, Lacquer is in no way as durable as Enamel and will require a clear coat (which will change the color) in order to even come close to the durability of Enamel.

P.S. You can do a quick color check by picking up a can of "recently discovered (by me)" Ace Hardware "Rust Stop" Allis Chalmers Orange, it is Enamel and almost a dead match to the original color.

Mike: Calypso Coral it is... it's a perfect match...the bed liner is going in Friday... in the same color [Calypso Coral]...


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