Maybe a blow through unit?

 

Contact modracer on here, I'm sure he'd be able to identify it for you.

 

Throw that POS in the trash.

 

Can't tune a carb eh

 

Probable loaded with aluminum shavings......

 

Sorta like an Aluminium Kinder Surprise, only drawback is it's always the same shit.............. aluminium shavings

Did BG have a part number for the shavings

 

Is it one of the old ported Holley's that BG did with the decals on the bowls or does it have the BG cast into the bowls? What are the scribed numbers on it?

 

I Won a bunch of races back in the late 80s when he first offered a carb that worked for my carb..
infact he was at a race .. saw my carb and asked me to pull it and bring it over to the trailer with my spark plugs.
he took the carb i purchsed from summit and then said here we will use this one...built me a carb on the spot in his trailer and did not charge me...infact he gave me back my original carb...
the tech guy in his trailer walked me through the new carb completely and explained to me everything he was doing and why...
i won alot with that carb... I will never forget this nor will i ever say anything bad about the guy.
he didnt have to do any of this...but he did...for free..
and i appreciated all of it very much

there are alot of extra features on his carbs...it make super fine tuning them accessible however it also can be complicated for the average holley guy...back then anyway.
i am confident thats where any negative rap comes from...its a better carb...and just not for everyone..

 

That's a great story. Let me tell you one about BG at a National Event in Houston. We had a Super Comp car and the BG fuel pump started leaking. The starter let us stuff a rag around it to absorb the fuel as it was a minor drip and make the qualifying run. I went to the BG trailer and waited until they were wrapped up with their day and asked if I could by a seal kit or fuel pump from them. They told me they were a racing operation and that what I really needed was to go to a parts store. I recall riding by their trailer after qualifying and asked them why a racing operation was loading up to leave before the show. Maybe I just caught them on a bad day.

 

I've done 2 brand new BG carbs, both had some aluminum shavings in the bowls. But you know what? Once I just cleaned and blew them out, both worked FREAKIN GREAT. (took all of 10 minutes each, and I even do it to new Holleys too)
Got a used BG carb from a buddy a few years ago that I converted to E85 and blow though myself, and it works great too.

 

New BG hurt my motor twice before I found the shavings... Still like the carbs when cleaned out...

 

Tuned them for years without issues on many pro class cars in most all of the sanctioning bodies and still run them myself on my own vehicles if I have the correct one for the application. Did some have shavings....yes but run enough carburetors and you will run into that on all brands of mass produced carburetors at one time or another. The important part is matching the size up correctly to the combination which is where many go wrong to start with and from there it does not matter what changes are made as it does not react properly. If you can tune a Holley then you can tune a BG or Demon.

 

I had one of the old BG stage 3 reaction time 750s and it was the best carb I ever had. I regret selling it several years ago.

 

TRUTH...the 750 "Stage III" flowed 930c.f.m.
4779S3
Still a BAD BITCH.

 

I been rebuilding all kinds of carbs for about 40 years, and IMHO, BG just about singlehandedly created the custom carb market. Yeah he made a few mistakes here and there, (got too big too fast, again, IMHO), but over all, a lot of his stuff was ahead of it's time.

 

I have an older 650 Demon that has flat out worked awsome.

 

I had a BG 750 on a engine I sold.

Bloke I sold it to tried a new Holley and tried to get a tune on that to no avail, then bought a QF and still couldn't get it quite right.

He then found the bloke he sold the BG to and bought it back.

 

Brand new BG carb 750 out of the box. Would not idle no matter what, kept having to feather the throttle.
Took carb apart, found that some passages simply did'nt line up between the main body and the metering blocks.
Checked all the numbers to make sure someone did'nt mix the main body with different blocks....all was "correct".

Sent it back in exchange for another one.
It would idle, but would not react or transition smoothly....more BS with the metering blocks and circuits.
Plus trash inside the bowls.
No thanks.
Holley HP carbs are much better.

 

Nothing but good from my mighty demon for the past 8 years

 

I have a Demon 650 right now, right out of the box, it has vacuum leak at the base plate.
Checked it out and the throttle shaft has about 1/32 of play in it!!....no bushing or seal around it.
They bored the throttle shaft hole too big and simply continued assembling the carb.
Quality control escapes them.

 

All I run right now is Demon carbs, have a 750 Race Demon on the car right now and does great. Did I have some carbs with metal shavings? Yup, both brand new carbs made years apart had junk in them. A 750 Speed Demon and an 850 Mighty Demon. Cleaned them up, installed and ran them. Seems like a lot of people just slap a carb on out of the box and expect it to run perfect, maybe change a jet size here and there. I spent quite a bit of time changing a lot of things on that 750 Race Demon and it drives and performs great. A custom carb builder will be doing the same but you're paying that shop to do that so you can just about bolt on and go.

 

The carbs I have are SUPPOSED to be bolt on and go. I could fix their problems if I wanted to, but I find the new HP series Holley carbs now come standard with many of the tricks that were considered 'tricks' just 10 years ago.
I have bolted them on and they ran flawlessly.

I do like the idea of the race Demons with changeable venturi's though.

 

The key was given already. If it's an original BG carb with the decals on the fuel bowls it's a great carb. It's ported and balanced with thin throttls shafts and flows about 870 cfm. That is a 80s or 90s carb when BG was Barry in his shop in Daloanaga <sp?>.It should have the 1 11/16 throttle plates and 4771S3 number (stage 3) It will run rich but that's an easy fix. My 509 BBC runs 71 primary 84 secondary jets
.063 pvcr, 075 idle air and 024 high speed bleed with an 033 IFR. I added an 075 bleed in the T-slot feed and the AFR is 14.4 straight across the rpm band with 12.6 @ wot.
write those specs down, if you have the right carb. Plus the metering blocks feed from the bottom which is what you want.

 

I have a 750 demon and wouldnt trade it for anything. Ive had 0 problems with it and my motor loves it!!

 

I bought one of the BG 750 Reaction Time Stage 3's brand new in the late 80's. Pretty spendy if I remember? It was and still is an awesome carb. I think all of the modified Holley's are pretty darn good. I will never let my 750 go!
I have heard about the problems with the Demons and have no experience with them but the Holley's were very nice.

 

Have BG 850 MD and a 750 SD very lightly used in boxes on a shelf where they belong.

 

I have a BG RS 830 with the blue sleeves, never had a bit of trouble, ran quite well, still have it but have moved on bigger, also ran BG Fuel pumps, 280, and now 400, never had any issues. Never saw any shavings, got it from Larry Morgan....

 

I have a 830 demon and it wouldnt idle for crap. Took it to my good friend Dan Davinci and he redid a couple of things. Damn good carb now. Dan is the man!

 

DragBoss....your car is cool as hell!!
I've always liked your car and the progress you made with it.:smt023

 

Thanks Big T, it runs good for old dinosaur Cleveland.....DragBoss