Slowly, but Surely

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6

69Chrgr

Charger/Cuda
Joined
Jan 29, 2007
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Midlothian, Texas
Well, after I fixed the exhaust valve fiasco, she definetely felt stronger. My 60' times went from 2.1 to 1.80. I ran a 7.74 @ 90.24 this time. However, now it seems that the secondary butterflies on my QF 750 D.P. aren't opening up all the way. When I have someone matt the accelerator and I look down the carb, the secondary throttle blades are only opened 3/4 the way. Also, my plugs were white after the runs. I hope my buddy 340sRule will chime in and give me some more of his opinions and advice. But dam this is fun, it's getting faster each time I run.:love7:
 
If the secondaries are'nt opening all the way check your linkage,check for binding,just give a good look over to see why they're not fully opening,as for the white plugs,sounds like your running lean fatten that bad boy up,what are you running for jets now??...
 
Don't know yet 340. I'm going to look at it this afternoon. A guy at the track showed me the linkage arm that adjusts the secondaries. He said it needs to be "tweaked" to fully engage the secodaries. However I went to QFT's website and they sell different sized rods to increase the progressiveness of the secondaries. What do you think? And will this 750 D.P. be enough? It seems like the motor is begging for more. Thanks for the feedback from everyone.
 
If the primaries are opened all the way and the secondaries are not, the progressive link must be bent out of wack, the wrong link has been installed or the arm attached to the secondary throttle pivot is spinning on the shaft (it's just peened on).

Get this fixed before you start to tune jets or power valves. A quick and dirty way to fix this fast is to have a buddy hold the accelerator wide open (with the engine off, lol!) and bend the link with two needle nose pliers until the secondaries are wide open.

If this is an older used carb that may have seen a lot of use, may I suggest replacing your base plate with a new one from Quickfuel? I have used their products and am very happy with them. The new base plate comes with three linkages, 1:1 (secondaries open in proportion to primaries), progessive (secondaries start to open @ about 1/2 throttle) and a super progressive (secondaries start to open at 3/4 throttle).

Older Holleys have seen a lot of abuse from over tightening, mongo return springs and mis-routed accelerator cables. All of these conditions cause exessive throttle shaft wear and vacuum leaks and lead to the I hate Holleys syndrome because I can't get it tuned/drops out of tune.

340s is right, it sounds like you're running lean, but get the secondaries taken care of first as it may be preventing your powervalve from opening by keeping manifold vaccum high.
 
I run the Quick Fuel 850 on mine,with 79 and 88 for the jets,i like to run it a little fat...
 
Hey Chrgr,
Ideal fuel ratio for a streeter is 14.7 pounds of fuel for each pound of air and we all know that, Right? I've read over and over that about 12.2/1 is close to ideal for max power.
I'd just keep jetting upward until you slow the car down, but you have to know that you have enough fuel pump. If the car's running out of fuel you'll not effect the topend mph no matter how it's jetted.
I had this problem several years ago.
 
ramcharger said:
If the primaries are opened all the way and the secondaries are not, the progressive link must be bent out of wack, the wrong link has been installed or the arm attached to the secondary throttle pivot is spinning on the shaft (it's just peened on).

Get this fixed before you start to tune jets or power valves. A quick and dirty way to fix this fast is to have a buddy hold the accelerator wide open (with the engine off, lol!) and bend the link with two needle nose pliers until the secondaries are wide open.

If this is an older used carb that may have seen a lot of use, may I suggest replacing your base plate with a new one from Quickfuel? I have used their products and am very happy with them. The new base plate comes with three linkages, 1:1 (secondaries open in proportion to primaries), progessive (secondaries start to open @ about 1/2 throttle) and a super progressive (secondaries start to open at 3/4 throttle).

Older Holleys have seen a lot of abuse from over tightening, mongo return springs and mis-routed accelerator cables. All of these conditions cause exessive throttle shaft wear and vacuum leaks and lead to the I hate Holleys syndrome because I can't get it tuned/drops out of tune.

340s is right, it sounds like you're running lean, but get the secondaries taken care of first as it may be preventing your powervalve from opening by keeping manifold vaccum high.
Click to expand...

This is exactly what happened. Just came in from the shop, looked in my QFT box, and low and behold it had the two extra secondary rods. I replaced the gold rod with the silver and now I can get WOT. I just don't understand why it wouldn't do that with the gold rod? I sure do appreciate everyones help as it is obvious I am very amateur at this. But I am happy that it seems to get faster and faster with every attempt. Trying to get everything dialed in at the 1/8th mile track before the Mopar Mini Nats at Ennis (1/4 mile). It 's making me earn it, but I have gained a lot of experience by these various small problems. 340, it seems you really have that car dialed in. What was your most recent time slip?

Thanks Again,
Darren
 
Wow! What a difference! I installed the silver secondary rod, and now that the secondaries open up much sooner an wide open, it seems much more responsive!
 
Last time out,which was back in October 11.02 @120,hopefully i'll be heading to the track in the next couple of weeks right now i have the top end apart,doing a little work to it..and should be putting the 4.30's w/spool in too...
 
Haha. I gotcha. I also run TTI's, love their fit as well. Just wondering if they made a size bigger, like maybe an 1 7/8. Just continue to kick *** with that thing, that's all I care about! That 10 second slip is waiting for you.:supz:
 
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