Re: My HMT 78 Chevy Monte Carlo
 

Thanks for the offer, but my demon is working just fine and I think I got a handle on the tuning aspect. It seems plenty rich and all I need to do lean out the idle and cruise by drilling out the pvcr's in the primary and installing a smaller jet. My 255 lph fuel pump should be good up to 600hp.

Re: My HMT 78 Chevy Monte Carlo
 

damn, like the blow thru system....keep it simple ;) plus you get that deep carb sound

Re: My HMT 78 Chevy Monte Carlo
 

thats because Joseph Davis isnt actually human. he is a hyper-dimentional being that can take human form and dispense with the wisdom.

Re: My HMT 78 Chevy Monte Carlo
 

I'm looking for suggestions. I've spent some time messing with the carb jetting. The car pulls like a raped ape, but watching the wideband, it leans out on the top end. Currently, I'm still running the mighty demon but with a mallory 4309 fuel pressure regulator. I've played with the jets and where it runs it's absolute best is with the current combo of 74 jets in front, 99 in the rear. I've drilled the PVCRs to .078. The carb still has the stock .110 needle and seats.
I tried making the high speed air bleeds smaller but the car still leans out at over 10lbs of boost. I'm running 32 degrees timing with the msd btm pulling 2 degrees per lb of boost giving me a total of 17 under full boost. I'm running the walbro inline 255lph fuel pump using the monte's stock pick up. It's wired right with 10 gauge wiring and a 30 amp relay.
When I restricted the high speed air bleeds, it did run richer in the mid range, but it stilled leaned out according to the ngk afx wideband. I've received advice from the V8 forum to try bigger needle and seats. I am going to try that because because it couldn't hurt. I'm looking for any other suggestions.
I want to make my current set up work without spending alot of money. I'm so close to 11 second glory I can taste it. This car would almost be done if all I wanted to do was run 10lbs of boost, but after feeling the 15lbs, I know that is what I need.

Re: My HMT 78 Chevy Monte Carlo
 

get a bigger main body.

Re: My HMT 78 Chevy Monte Carlo
 

nice setup man! props :6

Re: My HMT 78 Chevy Monte Carlo
 

Extend the vent tubes. Go to the turbo forumns and search for vent tube extensions. It will rich the car up alot and you will drop a lot of jet sizes. Other than that make sure fuel pressure is rising on a 1 to 1 ratio with boost.

Re: My HMT 78 Chevy Monte Carlo
 

I thought about that, but 650 carbs have gone in the 8s' on turbos. So I don't think my 750 is the problem.

I tried the vent tube extensions with 72 and 82 jetting and it was way too rich. The car would not rev cleanly without sputtering. Unless maybe my spark plugs have too cold a heat range. Right now it pulls off idle without any sputtering or hesitations all through out the rev range. Even when it leans out on top it still pulls hard, its just I let off due to what the wideband is reading.

Re: My HMT 78 Chevy Monte Carlo
 

I think you should get a Megasquirt :P

Re: My HMT 78 Chevy Monte Carlo
 

I get better fuel atomization with a carb than fuel injection. ;D