I AM!!! AAAAhhhhhh............................................................................................................face turn blue and he tips over.........................
Holley/Demon Carb stumble
- Thread starter Cudafever
- Start date
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I AM!!! AAAAhhhhhh............................................................................................................face turn blue and he tips over.........................
j par
Well-hung Member
I've stopped at one of the stores there a few times driving through.Why are you surprised?
A little town like ours, can't have a drag strip
Looks like you could drag race anywhere...
yellow rose
Overnight Sensation
so i'm throwing the demon back together today with some new parts that was left on the proform carb....like the fuel bowls........
They should put instruction that if you want to us the squirter pump, you have to do some drilling!
They should put instruction that if you want to us the squirter pump, you have to do some drilling!
PRH
Well-Known Member
Seems like a screw up to me.
I’d call them and see what the story is.
If the bowls aren’t supposed to be finish machined and ready to assemble...... I’d just send them back and get the QFT or Proform bowls.
I’d call them and see what the story is.
If the bowls aren’t supposed to be finish machined and ready to assemble...... I’d just send them back and get the QFT or Proform bowls.
Well to make matter worse, i ordered two secondary bowls
so the front one would be facing the wrong way for fuel inlet and sight glass.
not going to be ready for this week end... i guess i could make the $50 holley 3310 donate it fuel bowls just for testing.......going to have to think on this......not sure they will even fit..... we'll see.
so the front one would be facing the wrong way for fuel inlet and sight glass.not going to be ready for this week end... i guess i could make the $50 holley 3310 donate it fuel bowls just for testing.......going to have to think on this......not sure they will even fit..... we'll see.
PRH
Well-Known Member
Did you get secondary bowls for a vac secondary carb?
If so, the acc pump holes would all be blank.
Those PF bowls are looking better and better.
My recollection is they have dual fuel inlets and sight glasses........ can be used for either primary or secondary.
If so, the acc pump holes would all be blank.
Those PF bowls are looking better and better.
My recollection is they have dual fuel inlets and sight glasses........ can be used for either primary or secondary.
yellow rose
Overnight Sensation
Didn't have time to get the demon carb back together and didn't do anything to the proform one, same as last race.
Stumble is not 100% fixed but close. It stumbled the first test run but not a fall on your face stumble, more of a slight hesitation.
Ran flawlessly the rest of the day. and was vary consistent as well.
ran 7.94s to 7.93s all day long
Made it to the final round of competition and punched a RED light!
Temps were in the 50s and low 60s all day sun shine and no wind.
Was a real nice race day.
Had the GoPro on the roof of my car for sever test runs and then tried to set it up to read the o2 meter again.
haven't downloaded the video to know it its even visible on not but will let you know or show the video if its worth while.
Any hooo great day, didn't break anything and another racing season in the books.
Stumble is not 100% fixed but close. It stumbled the first test run but not a fall on your face stumble, more of a slight hesitation.
Ran flawlessly the rest of the day. and was vary consistent as well.
ran 7.94s to 7.93s all day long
Made it to the final round of competition and punched a RED light!
Temps were in the 50s and low 60s all day sun shine and no wind.
Was a real nice race day.
Had the GoPro on the roof of my car for sever test runs and then tried to set it up to read the o2 meter again.
haven't downloaded the video to know it its even visible on not but will let you know or show the video if its worth while.
Any hooo great day, didn't break anything and another racing season in the books.
Well i was hoping that this video would give me a little insight. but not really.
with the GoPro on the roof of my car i was hoping it would show me something. It darts left to right, but i already know that.
slowed down the video on one launch but then you don't see it sashay around at all.
The last half of the day i decided that i would put the GoPro in the back seat and see if it would pick up my o2 meter, to see how the carb was behaving threw the pull of each gear. NOPE even on my wide screen TV...........to far back bad angles Just nothing.
The last run when i red light you can see i just wasn't ready and CHOOOOKED!
But its only 6 minutes long so here you go any ways.
Injoy!!!!
with the GoPro on the roof of my car i was hoping it would show me something. It darts left to right, but i already know that.
slowed down the video on one launch but then you don't see it sashay around at all.
The last half of the day i decided that i would put the GoPro in the back seat and see if it would pick up my o2 meter, to see how the carb was behaving threw the pull of each gear. NOPE even on my wide screen TV...........to far back bad angles Just nothing.
The last run when i red light you can see i just wasn't ready and CHOOOOKED!
But its only 6 minutes long so here you go any ways.
Injoy!!!!
So i ordered the PF fuel bowls today. for a 4150 double pumper!
Back ordered until the 25th of this month.
O well it not like i can us my car much until spring around here.
Trying to decide on my winter project now.
Back ordered until the 25th of this month.
O well it not like i can us my car much until spring around here.
Trying to decide on my winter project now.
So this is what my winter project was/still is.
Stiff front end looking at aftermarket solutions
As i said back in Oct of last year, I order some ProForm fuel bowls. They have been in a box all winter as i have been working on my front end of my cuda.
Today i open up my box and decide that the proform is going to be a new carb with all new parts, and the demon bowls are going back on the demon carb.
all the new hardware parts the don't come with a new fuel bowl, like float bowl hardware and spring, needle and seat hardware, squirter hardware.
Hit the order button at Summit and it tells me that the fuel inlet(to match the demon so the swap will be simple between carbs) is backordered..........good thing i ordered early this time.
Have 7 week before the first Test and Tune!
So i will have the Demon 850 back to its original condition.......except the change of the 4.5 power valve in favor of a 6.5.......or maybe the 10.5 i have kicking around. haven't decided yet.
Start with the Proform 850 that is currently on the car, and switch to the Demon, to do some comparisons at the track. Whichever one works the best, will stay on the car
Then start my focus on a readable, data logging o2, that will help with the fine tuning of the Winning carb.
Stiff front end looking at aftermarket solutions
LOL Well...........the proform, likes them bowls
And i might as well have the same bowls on both carb. only need one tool if i have the proform on, or the demon. Also i ordered the same inlets so switching carbs is simple simple.
so i'm throwing the demon back together today with some new parts that was left on the proform carb....like the fuel bowls........
They should put instruction that if you want to us the squirter pump, you have to do some drilling!
As i said back in Oct of last year, I order some ProForm fuel bowls. They have been in a box all winter as i have been working on my front end of my cuda.
Today i open up my box and decide that the proform is going to be a new carb with all new parts, and the demon bowls are going back on the demon carb.
all the new hardware parts the don't come with a new fuel bowl, like float bowl hardware and spring, needle and seat hardware, squirter hardware.
Hit the order button at Summit and it tells me that the fuel inlet(to match the demon so the swap will be simple between carbs) is backordered..........good thing i ordered early this time.
Have 7 week before the first Test and Tune!
So i will have the Demon 850 back to its original condition.......except the change of the 4.5 power valve in favor of a 6.5.......or maybe the 10.5 i have kicking around. haven't decided yet.
Start with the Proform 850 that is currently on the car, and switch to the Demon, to do some comparisons at the track. Whichever one works the best, will stay on the car
Then start my focus on a readable, data logging o2, that will help with the fine tuning of the Winning carb.
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PRH
Well-Known Member
I’ve built a number of carbs through the years from various different “cores” to start with.
I built an HP950 from a “bare” Holley main body casting, where I had to install the boosters and vent tubes, etc, to the Proform main body upgrade “kits”, and then procured everything else required to build up a carb from scratch.
There’s a lot of miscellaneous screws/hardware/small parts you need to put one together if you’re starting from zero.
The last one I did, which I still haven’t run on anything yet, I built from one of the Holley HP750 main body upgrade kits.
I got QFT metering blocks, baseplate, bowls, and had some of the other stuff on hand necessary to finish it.
Pump covers, hardware, pump arms, etc.
It ended up costing a little more than what you could buy a Brawler Race 750 for....... which is basically the same thing.
The costs of all the needed trinkets to finish one up add up pretty quick.
I still have another “bare” genuine Holley HP1000 body and the annular boosters I’ll be putting in it, along with most of the other stuff required to finish it.
I’ll end up having spent waaay too much money on it in the end.
I’ve had all the parts for it for ages...... before there were so many choices for reasonably priced HP style carbs.
Two of my dyno carbs were built from std Holley main bodies that had been replaced with the Proform kits.
Then when various other pieces got replaced on other carbs....... baseplates, bowls, etc....... I’d use some of the old parts to go along with the old bodies.
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skrews
Well-Known Member
^^^ Agree with above. Trying to piece meal a carb together doesn't make dollars and cents unless you have a lot of spare Holley parts.
Agree 100%
The the ProForm, that i built, or i am finishing building. i could have bought at summit. for 500 dollars. Seam like a lot of money at the start. for sure, 100 dollars at a time........i'm into it more than that.
But i have learned and am learning a ton about these carbs in the long run.
If i keep the demon, will eventually buy another proform base plate because of the to large of holes drilled on the butterfly and the twisted throttle shaft on the primary butterfly..............But, then again,..... it didn't change a thing, the last time i replaced it.
The the ProForm, that i built, or i am finishing building. i could have bought at summit. for 500 dollars. Seam like a lot of money at the start. for sure, 100 dollars at a time........i'm into it more than that.
But i have learned and am learning a ton about these carbs in the long run.
If i keep the demon, will eventually buy another proform base plate because of the to large of holes drilled on the butterfly and the twisted throttle shaft on the primary butterfly..............But, then again,..... it didn't change a thing, the last time i replaced it.
I really think that the POWER VALVE is what fix the stumble not the metering block(calibration is better hands down.)But i thing the power valve was the biggest problem
all along. So i want the demon put back to its before or beginning tune up only with a NOT 4.5 POWER VALVE in it and see what happens.
I have the box the demon carb came in. It says right on the box, that it came with a 6.5 power valve not the 4.5 i put in it.
all along. So i want the demon put back to its before or beginning tune up only with a NOT 4.5 POWER VALVE in it and see what happens.
I have the box the demon carb came in. It says right on the box, that it came with a 6.5 power valve not the 4.5 i put in it.
mderoy340
Well-Known Member
Throttle plate and main body idle and transition passages are not the same as a Proform/QFT/Holley.Agree 100%
The the ProForm, that i built, or i am finishing building. i could have bought at summit. for 500 dollars. Seam like a lot of money at the start. for sure, 100 dollars at a time........i'm into it more than that.
But i have learned and am learning a ton about these carbs in the long run.
If i keep the demon, will eventually buy another proform base plate because of the to large of holes drilled on the butterfly and the twisted throttle shaft on the primary butterfly..............But, then again,..... it didn't change a thing, the last time i replaced it.
And that could very well, be why nothing fix my problem untel i add the proform metering block to the proform base plate and center section.
I don't know.
So what make you think the base plate is different between the proform and the demon?
mderoy340
Well-Known Member
Metering blocks will interchange. I'm talking about the location of the passages where the throttle plate and main body meet. Look at a Demon and Holley base gasket and you will see the different slot length.
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