Turbo Carb setups

tjnavyblue

Well-known member
Could everyone with a running turbo blow-through carb application take a moment and list:

1.Size (cfm) and brand of carb
2.Modifications done to carb (drilled metering block, etc.)
3.The engine setup this carb is on
4.Size of jets used
5.Altitude you typically drive at
6.Anything else you think would be good to know if someone were to duplicate your carb setup.

Many of you have discussed your setup in other threads, but I thought it'd be nice to have a condensed thread that documented blow-through carb setups that are currently running.
 
tjnavyblue":28vcgi12 said:
Could everyone with a running turbo blow-through carb application take a moment and list:

1.Size (cfm) and brand of carb
2.Modifications done to carb (drilled metering block, etc.)
3.The engine setup this carb is on
4.Size of jets used
5.Altitude you typically drive at
6.Anything else you think would be good to know if someone were to duplicate your carb setup.

Many of you have discussed your setup in other threads, but I thought it'd be nice to have a condensed thread that documented blow-through carb setups that are currently running.

1.) Carter YF from a '77 300. 210 CFM (I think?)
2.) Choke removed, fabricated solid float, various ports plugged w/ JB weld.
3.) Stock 200
4.) Jet currently drilled out to .125
5.) Couple hundred feet
6.) Seems to work ok, but haven't tried to quantify fuel mileage. I needed to replace the 10-32 screws that hold the aircleaner stud w/ 1/4-20 as they pulled out under boost. Fabricated float made it especially sensative to fuel pressure.
 
Off the top of my head....
1. 450cfm Holley. (although we'll be swapping in a 600DP from time to time)
2. enlarged PVCRs, vent tube extensions, removed choke horn, center hung floats.
3. 250cid, unported alum. head/intake, custom cam, forged pistons, stock bottom end otherwise.
4. 68 primaries/ 86 secondaries. (this changes frequently!)
5. 65 feet below sealevel at WOT! :shock: But around 4500-5500 density altitude here in Tucson.
6. We're running E85. So the jetting won't be close for gas. Right now the PV is a 8.5, but with the new cam I'll be able to increase this up to 10.5 or so.

Later,
Will
 
1. Holley 2300 350cfm rated at 3"Hg (it is actually 248cfm at 1.5"Hg).

2. www.hangar18fabrication.com/blowthru.html

3. stock 200, 0.040" over bore, 1.6 ratio rockers, stock cam, direct mount carb, 1.75 SS intake/1.43 SS exhaust valves, mild port/polish, 3 angle job, stock exhaust manifold "j-piped" into Garrett T3 "super 60", Walbro GLS 392 inline pump w/ aeromotive bypass regulator, etc...

4. jet# 66, iab's 0.075", hsab's 0.034", Quick fuel adjustable metering block w/ ifr's 0.028", PV 8.5, pvcr's 0.055", drilled a 0.094" hole in each throttle blade center towards t-slot, 8" extended vent tube in float bowl vent, top emulsion port blocked due to above fuel level in float bowl all other 6 are at 0.028", removed blow-out protection and jb-weld shut and re-routed vacuum signal into PV chamber via a mod'd timed-vacuum port.

5. sea level.

6. get ready for some R&D. There are so many things I have done in the past 3 years it is hard to recall and too much to list. I have a folder w/ @ 5" of all my notes on paper of my successes and failures. You are welcome to come by and read it...really. That will get you started in the right direction. As a suggestion, do not think one of these combos will work on another engine, each is specific to that engine.

Good luck,
Kirk

7. no lag
8. from idle to 5,500rpms
9. average of 10-12mpg, if into boost a lot @ 6mpg
 
350 holley with solid float milled choke.
stock 1978 shortblock with a 65 head.
stock cam
1.6 ratio roller rockers.
Clifford billet adaptor
GM intank pump (and tank) with aeromotive regulator (bypass style)
driven mostly at 500ft.

I haven't had the bowl off in over a year (nor has it relly been driven in that time) so not sure of my jetting....I think around a 60 though. electric pump and regulator made a HUGE difference over trying to use a referenced stock pump.
 
Could everyone post their horsepower (if known) as well as the characteristics of their engine (lag, rpm range, crusing mpg's)
 
Hmmm....
The last time we chassis dyno'd it we got 323hp and 502ft/lbs at the tires.
The 502ft/lbs. is debatable due to the torque converter, but even at 4000 rpm we were still over 400ft/lbs.

Fuel mileage.....Kelly consumes about 1 gallon per 1/4mile pass. This includes driving to the staging lanes, and driving back to the pits.
For street mileage we're in the 12-15 range I'd guess. I've never checked it. Again we're running E85 so our fuel usage is about 30% greater than normal.

Not much lag to speak of, at least not with the new cam. The big cam had quite a bit of lag though!
As for RPM range....I'd say 2500 up to at least 6500. We've never been that high, but it's still pulling very strong at 6200.
Will
 
450 CFM Holley 64 primaries 78 secondaries, .086" drilled Power valve circuit,
offset ground stock crank to 4.125"
Manley rods CP pistons, 8 to 1 comp.
Modified stock iron head, 62-1 Turbo @ 10 lbs boost
345HP 390ft lbs at the wheels
Just my opion but the 450 mech sec. Holley is junk for turbo app. no matter what you do, you'll have lean cylinders, use a 2 barrel, Nascar style 390 with acc. pumps on both sides, or EFI
 
Horsepower? More than stock, less than Will & Kelly?

As for characteristics - being a boosted stock engine, it basically feels just like a stock engine, except 50% more power at any given point. No noticeable lag or anything.

I am still way in the tuning and development phase tho.
 
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