I, and many others, have heard that blow through set-ups are not worth messing with. I would like some straight facts (AS SPECIFIC AS POSSIBLE) about what it took to make you happy. I built my car and could point out a million flaws with it...I am asking you guys to be critical about your set-ups. Other people saying "It won't work" just bugs me. Is it cold start, hot start, off idle (high vacuum), 0 vacuum ;boost transitioning, mixture distribution, accel pump problems....WHAT? I realize there is additional effort in tuning, and even that most Holleys (that I have seen at least) do not run the same, day to day, so.... what say you?
Thanks
Curt

My personal blow thru carb works flawless

idles and starts great, nice flat fuel curve and makes mega power.

the only complaint I have is blow thru turbo set ups are not real "snappy" because of the low air velocity off idle.

other than that..... it works good. i did have issues with my fuel regulator, but it was bad product selection on my part

that being said, any one looking for a c&s blow thru dominator....i have one for sale as i am gonna learn efi

I built my own carb using the hanger 18 mods website. I drilled my PVCR's out to 3/32nds and jetted up the secondaries and have been very surprised how well it has treated me. Under 10lbs of boost it just starts to go lean but I think a jet change will iron that out. My only complaint is right off idle and part throttle cruise the thing runs so rich it'll burn your eyes and I don't want to step down on the jet in fear of going lean before the transition to the secondaries so I've just lived with it. All in all it hasn't been the nightmare some have talked about. My car is not the most powerful boosted car out there but I think It's making around 375-400 at the wheels with a stock 318 and homebuilt carb. I have yet to take the car to the track because of transmission issues, but I've racked up 4-500 street miles with my blowthru with no issues

Mine didn't run bad at WOT, had a very nice a/f through. I only had 2 complaints with it. When trying to spool a larger turbo it was always fat at part throtle and could never get the a/f lean enough to get alot of turbo speed. And the first time you make a pass with fuel injection and get to see and use all the data from the pass, you will wonder why you ever spent money on the carb. IMHO Having both, I would never put a blow thru on anything again, just being able to change anything you want with a few key strokes is flat out awesome. In other words the carb worked great, ran good but the fuel injection is just leaps and bounds better.

I sent mine to Scott at SDCE http://www.sd-concepts.com/pages/cfHome.cfm

Thing worked right out of the box> Buddy runs a W5 headed SB at 170mph+ w/ a blow thru and 17lbs of boost no problems... seems to work just fine

Using the right parts as mentioned above is the ticket, EVEN with a six pack with 82/83 mech carbs seem to work well, I had to put dividers in the bonnet? to try to equal the flow out but so far so good. I took an older Mr Gasket al six pack scoop and welded a 1/4 plate on the bottom and simply made it a front entry setup with 4 dividers.

Just having a problem with 3k plus injectors to get a 3G hemi going.... close to 2 times the cost of carbed...
Curt

I think there's two ways to look at this situation. One: the blow thru carb does work, it just takes some finessing to get it right. It won't be as good as EFI but it will work. It's cheaper so you can get your car together and driving sooner and possibly be saving the money to get EFI going later down the road.
Two: you're wasting money on the carb that could go towards EFI.
Personally, I look at my car like a journey, not a destination. Sometimes I have to backtrack, but that's just part of the fun.

Mine works killer. Homebuilt, 650 DP. No mods to pvcr's or bleeds. I honestly believe in my case and others below 370" or so the 650 is the way to fly. Smaller venturis maybe pull harder out of the boosters? My car is jetted up 3/7 I think, (off the head, but it's been awhile, don't hold me to it, like 75/81)and has AFR's right around 12:1 at 13lbs of boost on pump 92. Made 400 to the tires with a very stock 318 and went 120 in the 1/4 at 3500 race weight.

A guy named Ira on theturboforums went like 5.80's on a 650 carb and a 355 with an ancient TV8101 single turbo.

What do you want to do with it?
A pure race carb is easy. A street/strip carb is a PITA.

A carb can only sense air velocity. It can't sense air density. You can tune well for one or the other but it's physically impossible for a carb to be tuned perfectly for both.
A good balance can be found but you really have to know what you're doing and there will always be a sacrifice.

I borrowed a Holley tuned by SDCE and it worked well. Anytime I needed more than the primaries open but less than medium boost it felt flat. There was just a hole in the tuning.
The AFB I had worked great for street use but couldn't keep up under boost. I ended up jetting the secondaries rich and running an additional injector.

Once I went EFI, I couldn't believe I fought with a carb for that long. I will not go blow through again.

If it's a street/strip car, I'd suggest doing what you can now to get you by and saving your money for a decent EFI system. You can get into them for minimal cost if you shop wisely. I bought my controller and many components used off eBag.

If you're building a drag car, have at it with the carb.

Good Morning Fellas !!!
This topic is making me SAD...
I my self is collecting all my Turbo Stuff to switch
over from a Nitrous Additive (440...30over...9to-1comp....Stealth home ported heads.....Victor intake port matched to heads....W/a Fogger sys.......in an a Body running high nines .........to a Turbo set up...
Now i read this so i'm sad....
would i improve the E.T. by swithing to a 88mm Turbo set up Intercooled air to air Blowthrow?...
Sorry to crash the topic but it has my FULL attention

A blow through is fine for a drag car. You don't need to worry about drivability concers while cruising.

You might need a cam change but the turbo will be easier on your engine than the bottle.

I agree with the whole fuel injection for the street vehicle, BUT it isn't impossible to make a carb work well. I admit that I am probably a bit more accepting of small driveability issues when it comes to my daily driver, but my procharged 71 dart is a whole bunch more driver friendly than some of my past N/A vehicles.

I have a 408 with a P600B, self ported Edelbrock heads, hydaulic flat tappet cam, intercooler, 750 quickfuel mainbodied 4150 with E85 metering blocks. It will only make 6 pounds spinning the blower to it's max rpm, but it runs 10.70s @ 127mph with 3.55s all day long. It took a while to fine tune the air bleeds to keep the wideband reading consistant for idle, cruise, and WOT...but, I kinda enjoy that part of the process. It also took some ingeuity to figure out a fuel supply sytem that would feed enough E85 to the engine through single needle and seat float bowls!

Keep in mind that I race at 8500+ feet DA, and drive it to work at 6500ft elevation. For a fairly tame 3600 pound car it is very driver friendly...instant response without any hesitation, no blubbering, and idles pretty decent at 800rpm at the stop lights.

Don't get me wrong, if somebody gave my a nice multiport fuel injection setup I would swap my carb out in a heartbeat!

It really depends on how picky you are. I like to have a car that starts up and idles right away even when it is 40* out. I like to datalog all the sensors and fuel. I like to not have any hard hot start issues when it is really hot out. Bad thing with a carb is if you set it up to run perfect hot it doesn't work perfect cold. Set it up to start and run perfect cold it is pig rich hot.

I tried to balance the drivability line with a carb and it failed badly but I am a picky [Edited by Moparts - Family Friendly Site - Keep it clean]. Even after my truck sits for over a month with EFI I just walk up to it and turn the key and it fires to life. Just doesn't happen with a carb.