Tonight watching Monster garage, they did a turbo VW drag car. They used a draw thru carb design... not blow thru... the turbo pulled the air and fuel from the carb. looked very simple and basis. Any issues with this set up? does it effect the turbo with the fuel going thru it? any draw backs?

Mike

 

Can't be intercooled, poor throttle response, need carbon seals in the turbo, need a massive carb, hard on the turbo impeller.

Blow thru is vastly superior.

 

what he said^

 

Yeah, I noticed that on the show... no intercooler and they used a demon carb on the 4cyl vw.

 

was it this?

 

thats a suck through adapter, used on rvs mostly.

Steve

 

Looks like a fairly standard 70's type drawthru setup for a SBC. FWIW, drawthru setups on VW's are fairly common. In fact, there are still places offering up kits.

 

Just watched it on the second showing. That was a cool setup.

 

QFT!

(Quoted For Truth)

 

not to mention if the car backfires @ all your turbo is loaded w/ fuel which seem like it could pop like the big ole wiends do on some cars. the car seemed pretty cool though otherwise... its a bummer they don't give 'em enough time to mess with efi i think that would be a neat bug... & they had plenty of room for an air/water intercooler had they not setup the carb like that. i mean thats like putting the throttle body before the turbo... just seems sorta dumb

 

Hmm, I wonder if you could use a OE Solex or 2-barrel Weber for a blowthrough......I don't want to think of the tubing nightmare with a twin carb setup. Now where to stick a intercooler and keep everything under the hood.

 

VW... The intercooler and tubing would fit under the hood just take out the spare tire. The motor and carbs would still fit under the trunk.

 

Hmm, nah I think I will finish the Mustang first, then maybe do the Turbo Bug thing.

 

Turbo Bug would be cooler, we ran into one up in College Station years ago and that thing was dead stopped when my friend with his tree-fifdy nailed it from 40mph, needless to say that Bug SHOT past him like he was not moving. There is just no way to explain the ego damaging capabilities of a stupid fast VW Bug.

 

Yah I know, nothing like getting smacked around by a 30 or 40 year old air-cooled 4-cyl car. :loll:

 

There was a guy around here a long time ago that had a turbo VW motor in a rail buggie that he drove on the street all the time. Had pretty fat sticky tires on the back and skinnies on the front. Needless to say, it would pick the front end up anytime he wanted with no problems at all and carry it on the wheelie bars. Fun car to watch. If I remember right, I think it ran mid-high 10s.

 

wow...all kinds of draw through trash talk

draw through can indeed be intercooled, as its been done quite a few times in the turbo dodge world, it works in an EFI setup, but not in a carb setup

but then think about what happens when youre on a 2-step rev limiter, your pushing unburnt fuel into your exhaust manifold, and it ignites in there, i forgot the name of the process, but i know someone can futher elaborate, but its used to produce more boost when youre launching, so if it works in that case, why would it be so hazardous in the turbo, the turbo already see's huge EGT's, i think its durable enough to handle a mild backfire

a nice advantage of draw through, with my dodge, it was instant spool with the T3, not a hint of lag, i was at full boost by 2,100 rpms or so, and that was with only a removed muffler, and the fact that your turbo never gets to experience compressor surge

 

20 years ago in TX a buddy of mine a Karmann Ghia and it ran low 11s. He could not keep transaxles in it. He would scatter them about one every 2 months. VW are the original imports. Not ricers, these things had brats & beer!:stickpk:

 

I've got a 68 Beelte with a Porsche 5 speed transaxle, and Porsche trailing arms and brakes. It was gonna get a turbo'd mazda rotary engine...that was until I bought my TA and now the bug just sits in the parts room at the shop. One day once the T/A is finished and back on the road, TTs and all, I might get back to working on the bug. Should be a heck of a fun street car that could turn in the low 11s.

 

Two different ends of the turbo, Fuel in the turbine housing not as bad as fuel puddling in the compressor housing and then having it ignite.

I have thought abuot going draw through, but everywhere I read throttle responce is quicker with the blow through, and also idle control is easier with the blow through, since all the pipng and intercooler after the TB become a part of the plenum and make control at best difficult. Not to mention if you get a leak in a hose, or blow a coupling (as turbo cars seemed to from time to time. ) then instant WOT, no matter where the throttle position is.

Drawthrough does have teh advantage of not needing a BOV and will slow the turbo based on lack of air allowed to reach the compressor wheel which can actuall be nicer for the turbo itself, but not enough of an advatage in my eyes to warrant building a drawthrough set-up.