stupid BG tech support

[BlueMonster65]

i called Barry Grant today to get some info on what carb they would recommend for a blowthru SC. application. and they told me they don't make one that will work with that setup. i said well both ATI and Paxton say a holley 4150 or mighty demon will work, so whats the deal. he said that a blow thru will create unequal fuel/ air pressure and fuel will leak out the throttle shafts and cause my car to burst into flames. he was a real mean duchebag. and his name was NICK with rymes with another name for richard. i asked him what can i do to use a demon in a blowthru applicatin. he said i can't becuase they don't make one. i said well a demon is the same as a holley why won't it work. he said because the throttle shafts don't have bushings. at that point i realized he was not knowledgable enough to help anyone and was not interested in helping me. i have rebuilt 4 holleys and none of them had bushings in the throttle plates. i'm thinking of calling barry grant himself to find out what i can do to run a demon. i refuse to let a low intelligence ackwards bass reject squish my dreams.

that being said anybody running a Mighty demon with a supercharger in a blow thru configuration?

 

[brianj5600]

You might try turbomustangs.com they have a great blow thru section on their forum. There are some nice helpful people there. I've seen a few people with them there.

 

[DJs350H]

Ok, so I was reading Mustang & Fords earlier this evening and I reached an artice about carb selection. Well I read it and a kid asked about a carb for supercharging. They said, "Now for your question concerning a supercharger for your car--there is a charger available for cars with carburetors: the Paxton Novi 1200. This supercharger is available in left-hand mount, right-hand mount, polished or satin. There are also some pulley upgrades for additional boost. It is recommended you use a Mighty Demon 650 (PN 5282010GC). Adding superchargers may require radiator upgrades, forged pistons, and a better cam to get the most bang for you buck..."

Um, so yeah it sounds like you were talking to someone not very knowledgeable of their own product line. Yeah, I don't think Mr. Grant would be too happy about that. Whoever you get your supercharger from should be able to help refer to you some part numbers for carbs to work with their product. I have heard of plenty of people buying a Holley and having it modified to work with a blow-through SC application.

Oh yeah...this will really help too...

http://www.jason.fletcher.net/tech/paxton/paxtonphotos.htm

Read the captions under the pictures....they actually show pics of mods being done to a Holley for the SC application, and list a few part numbers for the needed parts etc...

There is also a guy that works at "Paradise Wheels" (I read this a long time ago so forgive me if I'm wrong) that rebuilds the older style Paxtons (the one's before they changed the bonnet design etc). I think he knows his stuff....he should be able to help you out with any questions. I believe the new style Paxton doesn't fit under a stock hood, and the old one definately does...

Hope this helps,
DJ

P.S. I used to want a SC once....lol...so I did a bit of research.

 

[latamud]

Sorry for the long reply

Look, just use the demon carb in any setup you want. Any setup you'd have a Holley in, replace the Holley with a Demon, yes they are the same, in a sense, shape, size, but the demon will perform better. Make sure you are using hardened floats, the black plastic kind(phenolic?), not the brass. I think these are standard in carbs now-a-days anyways but check. The fuel pressure thing is that as boost pressure increases it will force air into the carb, and the pressure will push the fuel back out of the float bowls. To counter this there is usually a fitting on the exhaust side of the charger for a boost gague. Tap off that line and run it to a fuel pressure regulator with a boost port that matches the boost pressures on the outside of the carb. So when the pressure inside the carb rises the outside fuel pressure cancels it out and you keep fuel in the carb. Some aftermarket mechanical fuel pumps have a port inlet for the boost from the charger. Just run a vacuum line to it and that takes care of the problem and is cheaper than the regulator. Have fun. Oh, if you buy a new kit, it usually has one of the two mentioned boost balance mechanisms.

 

[rbohm]

if you use the carb box that paxton supplies with their kits, then you can use any carb that fits in the box. otherwise there are a couple of mods that need to be done to seal the throttle shafts. usually you drill a small hole in the carb base untill you hit the shaft, then make a base plate that has passages that match up to these holes, and run a line to the junction of these passages to the outlet side of the blower(before the carb) and the boost pressure will seal the shaft. often times though the shafts on new carbs are tight enough that you dont need to do this untill they loosen up.

 

[BlueMonster65]

rbohm i think i understand what you are saying but let me see. when you say "make a baseplate" you mean like a spacer between the carb and manifold where i can tap it for vacume lines? i agree to that a new carb shouldn't need this mod. are you familiar with boost referencing a dead head regulator? i found one from product enginnering but it s pretty expensive and i think its really just a modified BG or magnaflow unit. there is a magnaflow regulator that i think will work but it says its for EFI. any ideas?

i can't run a mech pump so thats not an option and i really don't want to use the big heavy "box" i'd rather do the necessary modificatins to a carb to allow me to use the bonnet.

thanks for the help.

 

[rbohm]

check out a book called turbochargers from HP books. there is a diagram of the base plate to which i refer. basically you want to create passages that do not run into the vacuum side of the carb. they must remain seperate. these passages will only run boost pressure to the throttle shafts to seal them when the boost comes on.

 

[brianj5600]

http://www.hangar18fabrication.com/blowthru.html

 

[mdjay]

Ok, so I was reading Mustang & Fords earlier this evening and I reached an artice about carb selection. Well I read it and a kid asked about a carb for supercharging. They said, "Now for your question concerning a supercharger for your car--there is a charger available for cars with carburetors: the Paxton Novi 1200. This supercharger is available in left-hand mount, right-hand mount, polished or satin. There are also some pulley upgrades for additional boost. It is recommended you use a Mighty Demon 650 (PN 5282010GC). Adding superchargers may require radiator upgrades, forged pistons, and a better cam to get the most bang for you buck..."

Um, so yeah it sounds like you were talking to someone not very knowledgeable of their own product line. Yeah, I don't think Mr. Grant would be too happy about that. Whoever you get your supercharger from should be able to help refer to you some part numbers for carbs to work with their product. I have heard of plenty of people buying a Holley and having it modified to work with a blow-through SC application.

Oh yeah...this will really help too...

http://www.jason.fletcher.net/tech/paxton/paxtonphotos.htm

Read the captions under the pictures....they actually show pics of mods being done to a Holley for the SC application, and list a few part numbers for the needed parts etc...

There is also a guy that works at "Paradise Wheels" (I read this a long time ago so forgive me if I'm wrong) that rebuilds the older style Paxtons (the one's before they changed the bonnet design etc). I think he knows his stuff....he should be able to help you out with any questions. I believe the new style Paxton doesn't fit under a stock hood, and the old one definately does...

Hope this helps,
DJ

P.S. I used to want a SC once....lol...so I did a bit of research.

He is looking at using a set-up like this.
http://www.mustangdepot.com/CarShows/images/qm04/DSCF0036.JPG

You are referring to the bonnet like this
http://www.mustangdepot.com/Media/images/e-gallery/DSCF0014.JPG

You are completely correct about the bonnet style, but the blow through has a different affect on the carb.

I agree completely about the Demon as the supperior choice! My experience with Holley carbs has been good, just inconsistent and easy to flood!

 

[BlueMonster65]

thanks guys, i read that hangar18... website and it is exactly how i modified the holley 600dp that i plan to use. i also believe that a MD650 will work without the throttle shaft modification since that really only becomes a problem with worn baseplates or high boost. thanks for the book reference i will be looking to purchase that soon. you are correct mdjay i don't plan on using the paxton box at this time. i would like to use the extreme velocity bonnet because i have heard many good things abot it and it will be different than any other 65 i have seen around here.

 

[TOM B]

Im running a blowthrough paxton, I bought a Holey commander 950 TBI.
It works great with no fuel leaks at 10 psi. tell that jerk at BG to get a life!