Dual quads versus big hammer!!!...

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I can see it's some kind of divider plate down in the secondary witch does me no good...
 
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I tried the fattest metering rods and turn the idle mixture screws back out to 1 and 1/2 turns. Idle rich and smell rich. Mid-range hesitation still there.. turn the idle mixture screws back into about 1 turn out. Idle came back up to normal readings and took it for a very short driveand I noticed like yesterday when I came to a stop the idle would dive and it would go very lean... I still think I don't have the correct Springs and would like the leaner primary Jets.... I'll try calling Holley in the morning LOL and try getting those air doors again LOL...
 
j par said:
@yellow rose remember this suggestion and conversation? They sent me the wrong stuff! LOL just when I was giving one of those kids on the tech line some credit.. they sent me four of these old divider plates that go down in the secondaries... Absolutely no use.. I'll call again tomorrow morning and see if I can get them to send the right thing...
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Unbelieveable. Just unreal.

Dude, you have the bad luck of myself.
 
yellow rose said:
Unbelieveable. Just unreal.

Dude, you have the bad luck of myself.
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I took a quick note on the Edelbrocks. the 500 Edelbrock specifically tuned for dual quads.. and the same 500 Edelbrock as a standalone..
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Just a little bit more evidence that I feel I'm heading in the right direction by leaning the primaries...
 
A- that’s classic.
Getting the wrong parts is a situation that pretty much every hot rodder has “enjoyed”.

B- non-helpful post #3........

None of my Holley’s have air doors(or those little divider things)...... or metering rods.

Just sayin’:poke:
 
after the rod size is taken into account, looks like the dual quad Ede’s are about 6 numbers leaner on the primary side.

Without pinning the air bleeds, no idea if there are also other calibration changes not reflected in the jet/rod sizes.
 
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PRH said:
after the rod size is taken into account, looks like the dual quad Ede’s are about 6 numbers leaner on the primary side.

With pinning the air bleeds, no idea if there are also other calibration changes not reflected in the jet/rod sizes.
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It's about all I have to go off of and making comparisons. Edelbrock has it down to a science where things are almost infinitely adjustable. I'm very much limited to what's made for the street demon. Of course you know I learned all of this afterwards..
It boils down to the $576 I paid for both the carburetors and about $100 in tune up parts. I've seen people pay near twice that for one carburetor and three to four times that for tune up parts to make it work. And again they start run accelerate turn off great... I just seem to be missing one or two things in the tune-up to make them perfect...
And it certainly like you said wasn't a case where I intentionally bought something that I knew wouldn't work for my car and trying to make it work. These are in many ways very close to the two 600 I had on my car for years now. In my mind I thought just a newer updated version. Again the Edelbrocks have much more available parts for tuning...
In the end I feel I'm close to halfway there and getting these set correctly. But they won't get completely thrown out of the picture until they've had their day at the track..
I'll get the 74 primary Jets today according to my tracking number and get them in over the weekend.
I've got three or four more tricks up my sleeve for these carburetors that I have to exercise....
 
I’m not saying you intentionally bought the wrong carbs.
It’s what you said vs what I “hear”.

You said: “I’m buying two street Demon 625’s for my TR and I’m going to put 2” open spacers under them”.
It should be great!!

I “heard” : “I’m buying two carbs that aren’t really suited for my TR, and I’m going to make matters worse by using 2” open spacers under them”.
It should be a real challenge!!
 
PRH said:
I’m not saying you intentionally bought the wrong carbs.
It’s what you said vs what I “hear”.

You said: “I’m buying two street Demon 625’s for my TR and I’m going to put 2” open spacers under them”.
It should be great!!

I “heard” : “I’m buying two carbs that aren’t really suited for my TR, and I’m going to make matters worse by using 2” open spacers under them”.
It should be a real challenge!!
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Do you really think the two inch open spacers are hurting?..
 
So, you’re at $676...... so far.

Those QFT carbs would have been $30 more....... and use low cost, readily available Holley tuning parts....... and are designed for exactly how you want to use them.
 
PRH said:
So, you’re at $676...... so far.

Those QFT carbs would have been $30 more....... and use low cost, readily available Holley tuning parts....... and are designed for exactly how you want to use them.
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when he posted that thread "talk me out of these", we told him buy holleys. He said "couldn't afford them".... but, as usual, cost about the same. He could have been shifting gears and kicking rears, but instead, he's "bogged" down.
 
318willrun said:
when he posted that thread "talk me out of these", we told him buy holleys. He said "couldn't afford them".... but, as usual, cost about the same. He could have been shifting gears and kicking rears, but instead, he's "bogged" down.
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They are Holleys...
 
318willrun said:
when he posted that thread "talk me out of these", we told him buy holleys. He said "couldn't afford them".... but, as usual, cost about the same. He could have been shifting gears and kicking rears, but instead, he's "bogged" down.
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I aint got an iron in this fire , and not intending to step on anyones toes , but a demon carb would be the last on my list if hunting a new carb .-------jmo
 
PRH said:
So, you’re at $676...... so far.

Those QFT carbs would have been $30 more....... and use low cost, readily available Holley tuning parts....... and are designed for exactly how you want to use them.
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We went over this before correct? I'm not what you call Cookie cutter material..
well I'm disappointed in the lack of available parts for the carburetor I'm not disappointed in the carburetor overall...
It's still hold on for your dear life when I hit the loud pedal... Because it has a bit of a stumble or cough in a not so usual situation doesn't mean the carburetors are junk. and if I bought the cookie-cutter combination that you just pointed out there's no guarantee that they're going to perform perfect out of the box and not have to buy tune up parts...?
 
318willrun said:
when he posted that thread "talk me out of these", we told him buy holleys. He said "couldn't afford them".... but, as usual, cost about the same. He could have been shifting gears and kicking rears, but instead, he's "bogged" down.
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It is shifting gears and kicking rears... Honestly could just be a little bit more of my combination then the carburetors fault. It's still a pretty rowdy cam with the gears that I have.. like I said when it's on it's on! Generally when you're racing you don't let off cruise for a while and then try to stomp it LOL..
 
j par said:
Do you really think the two inch open spacers are hurting?..
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I’m not there seeing how things are playing out.
A lot of it is “feeling” how the motor behaves, and when it does certain things in relation to throttle movement.

But, if there are tip in issues........ask yourself....... where is the squirter....... and where is the combustion chamber(you know, the place where the rich/lean thing happens)?

And....... what’s in between them?

If the squirter was 12” farther away from the chamber....... would you expect the problem to get better or worse?
How about 24” farther away?

If the squirters discharged directly into the intake port of the head, right behind the valve...... better or worse?

Thats not even talking about the “accumulator effect” of having all that plenum volume dampening the signal to the carb.

But....... it also may not matter at all on that combo.
As with most everything in this hobby..... there’s only one way to know for sure.
 
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PRH said:
I’m not there seeing how things are playing out.
A lot of is “feeling” how the motor behaves, and when it doesn’t certain things in relation to throttle movement.

But if there are tip in issues........ask yourself....... where is the squirter....... and where is the combustion chamber(you know, the place where the rich/lean thing happens)?

And....... what’s in between them?

If the squirter was 12” farther away from the chamber....... would you expect the problem to get better or worse?
How about 24” farther away?

If the squirters discharged directly into the intake port of the head, right behind the valve...... better or worse?

Thats not even talking about the “accumulator effect” of having all that plenum volume dampening the signal to the carb.

But....... it also may not matter at all on that combo.
As with most everything in this hobby..... there’s only one way to know for sure.
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my mind always goes to those two huge cross rams they put on the Big blocks back when...
Also I do get direct port fuel injection as opposed to what I have set up. I don't believe it was ever meant for Street driving but here I am. I could have done a million different cookie cutter things to make this operate better...
It's almost like I could just do you like the doctor says and if it hurts don't do that LOL if I would stop looking for it and trying to make it happen it probably wouldn't even bother me... It's not at initial tip in and it's not bogging off the line or doing anything abnormal anywhere else. If I just let out the clutch and punch it it just ignites the tires.. I can bang through the gears and it pulls like a freight train... And if I downshift and punch it it takes off like a rocket.. but if I'm cruising along in third gear at say 25 to 3 Grand and punch it, it coughs a little bit sputters or whatever you want to call it then grabs and takes off like a bat out of hell...
 
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What about if you “roll into it” instead of punch it?

Maybe all that has to happen is a little more drivers finesse.

Sounds like they’re pretty close.
 
PRH said:
What about if you “roll into it” instead of punch it?

Maybe all that has to happen is a little more drivers finesse.

Sounds like they’re pretty close.
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If I roll into it it's fine... I can definitely finesse it a little bit especially when I know it's there... Kind of like I was saying the doctor says if it hurts when you do that don't do that LOL..
 
j par said:
If I roll into it it's fine... I can definitely finesse it a little bit especially when I know it's there... Kind of like I was saying the doctor says if it hurts when you do that don't do that LOL..
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I was just thinking... around here they have a lot of 4x4 mud bogs. I bet your car would do good in a mud bog...

:lol:

Sorry, I had to. Now, I'll get outside and get something done!
 
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