[GTOGEORGE]

Originally Posted by twooldgoats

The pattern will depend on your blower outlet and the pattern will almost certainly be different from your old blower. That's where individual cylinder EGT's are so helpful.

Jim

It would be nice but I don’t have 8 cylinder egt also o data recorder readings.


GTO George

[Tom Vaught]

A good "state of the Art" Portable Fluke Meter (like the one from this company):
https://www.testequipmentdepot.com/f...ters/index.htm would be about $460.00


and the individual thermo-couples /wires would be $130 each so 130 X 8 = $1,040 plus = $1500 for the ability to read exhaust temps.

Weller 0053119099 0.50 mm Type K External Temperature Sensor for WCB2 Calibrator and WHP1000, WHA3000P & WHA3000V Stations

So not a cheap purchase, as you know Jim.

Just saying.

I have similar parts to the above but a few years older on the shelf but we don't use them much anymore at where I worked 5 years ago. Better stuff out there for dyno testing. Does KRE use thermo-couples in their testing, George?

Tom V.

[johnta1]

If the plugs are that bad, I'd say you are way, way too lean.
Carbs at their max jetting for alcohol use?

Alcohol is very forgiving with rich mixtures. Lean not at all. (burned plug tips, holes in pistons, etc)

With a better blower, it's probably using a ton more 'air' so needs a ton more fuel to go with it. Bigger carbs needed?

Or injection?!!

[GTOGEORGE]

Originally Posted by johnta1

If the plugs are that bad, I'd say you are way, way too lean.
Carbs at their max jetting for alcohol use?

Alcohol is very forgiving with rich mixtures. Lean not at all. (burned plug tips, holes in pistons, etc)

With a better blower, it's probably using a ton more 'air' so needs a ton more fuel to go with it. Bigger carbs needed?

Or injection?!!

218 on jet size.

George

[GTOGEORGE]

Rear plugs.

[GTOGEORGE]

Still weird that if the air mixture from the blower is pushed to the back then why aren’t my front cylinders melting plugs?


GTO George

[johnta1]

If you had injection, I'd say put bigger nozzles for those cylinders?

With carbs, jet it up more and hope for the best?

[GTOGEORGE]

looks like as of now ill be putting my other blower on for the pontiac race!



GTO George

[Tom Vaught]

Originally Posted by GTOGEORGE

So this upgrading to a high helix blower is getting to be a Chinese fire drill. I thought when I first started that it would be a direct change.....NOPE. They (TBS) have 2 versions of the high helix blower one sits 9/16” further back then mine (going to hit the distributor) and the 2nd version sits WAY forward.......seriously? Don’t know which way to go BUT it will happen! GTO George

Hope that after you swap the parts back, you get your distribution issues resolved for the Pontiac race (by using the old supercharger parts).

If that works then you have a Blower Air Distribution issue with the rear cylinders running lean, with your current manifold, I believe you posted. If the rear cylinder are getting more air, now the jetting on the carbs has to be able to add that extra fuel required to those rear cylinders.
Are you maxed out on the carb jetting?

At some point you can go up 30 jet sizes and the carb passages will not be able to flow the fuel thru the current carb DRILLED passages. THEN IT IS INJECTION TIME, as Jim and others have said.

Tom V.

[GTOGEORGE]

Well was able to talk to my Top/Dragster buddy about his combo....and mine. He came to the same conclusion that I did.........if the rotors are pushing the fuel mixture back (and they are) the back cylinder shouldn't be lean! Also he said forget about the site glass in the carbs when running a blower there a fine line with the very fuel level.....basically you want them as HIGH as possible!! After trouble shooting (im pretty good at it, being a Millwright for 43 years....i learned a lot) my fuel system the only thing it could be is my carbs float level BUT it doesn't explain why the back are lean and the front aren't.
So im putting my original 8-71 back on for the pontiac race.

GTO George

[Tom Vaught]

Based on the picture of your blower discharge and the fact that the discharge openings are forward on the manifold (both the rectangular discharge and the triangle discharge vs centered, You said the supercharger WAS designed for no distributor back there, I have a question, is your Top Dragster buddy running the exact design BDS intake manifold as you and the same supercharger exactly as you?

Otherwise you do not know.

I went to Eaton Corporation in Marshall Michigan, about 15 years ago, and we did the exact studies (that you need to know for sure), on Ford supercharged Research engines.

Just saying, everyone has an opinion (without data) and the Thermocouples and data logger would give you the answer vs an opinion immediately. One piece of DATA is worth 1000 Opinions, my boss used to say. I am done with this one.

Tom V.

[GTOGEORGE]

Go Home!


GTO George

[GTOGEORGE]

After removing the intake I really didn't find anything.......MAYBE I had a couple of bolts that were bottoming out, ill remeasure them later to be sure.



GTO George

[Stan Weiss]

Originally Posted by GTOGEORGE

Well was able to talk to my Top/Dragster buddy about his combo....and mine. He came to the same conclusion that I did.........if the rotors are pushing the fuel mixture back (and they are) the back cylinder shouldn't be lean! Also he said forget about the site glass in the carbs when running a blower there a fine line with the very fuel level.....basically you want them as HIGH as possible!! After trouble shooting (im pretty good at it, being a Millwright for 43 years....i learned a lot) my fuel system the only thing it could be is my carbs float level BUT it doesn't explain why the back are lean and the front aren't.
So im putting my original 8-71 back on for the pontiac race.

GTO George

If the air and fuel stay together yes, but if the air wants to move more than the fuel does to the back then no.

Stan

[GTOGEORGE]

Originally Posted by Stan Weiss

If the air and fuel stay together yes, but if the air wants to move more than the fuel does to the back then no.

Stan

If


GTO George

[Stan Weiss]

Originally Posted by GTOGEORGE

Well was able to talk to my Top/Dragster buddy about his combo....and mine. He came to the same conclusion that I did.........if the rotors are pushing the fuel mixture back (and they are) the back cylinder shouldn't be lean! Also he said forget about the site glass in the carbs when running a blower there a fine line with the very fuel level.....basically you want them as HIGH as possible!! After trouble shooting (im pretty good at it, being a Millwright for 43 years....i learned a lot) my fuel system the only thing it could be is my carbs float level BUT it doesn't explain why the back are lean and the front aren't.
So im putting my original 8-71 back on for the pontiac race.

GTO George

If

Stan

[GTOGEORGE]

Originally Posted by Stan Weiss

If the air and fuel stay together yes, but if the air wants to move more than the fuel does to the back then no.

Stan

Not likely but interesting!


GTO George

[GTOGEORGE]

As im getting my engine/car back together for the Pontiac race nothing has stood out as a cause, except for some tuning which is what i first thought. The not getting the floats really high I think could be the real cause....supercharger engines need a lot of fuel specially alcohol engines. I had my carbs redone (last year) at APD so they can flow a lot of fuel....its the tuning part and that takes time........1/4 mile hits. Hopefully I can learn a few more things at Norwalk with the old blower on. All these tracks are running sissy 1/8 mile stuff its hard to get REAL Data......I miss 1/4 mile racing! I didn't get enough hits last time at Norwalk to trouble shoot the issue although I did rule out a few things.


GTO George

[GTOGEORGE]

Funny story about carbs and Roots Blowers......A friend of mine has a Roots Blower BB Chevy Dragster that runs Top/Dragster (Very Fast) any ways he at one time took the jets out of his carbs (2 - APD Alcohol Dominators) and he couldn't tell the differences........pretty funny!! Also adjusting the floats on them he said to put a piece of tape over the site glass window and raise the floats until they are pouring in the engine then start backing them off a little at a time when they stop then leave them at that........blower engines need a lot of fuel! True Story!


GTO George

[twooldgoats]

George,
It's so much easier and more accurate with mechanical injection that has hat and port injectors. I can tune my engine for any track and any weather with a few jet changes. I know you've made a big commitment to carbs, but maybe you're at the limit. You're making a ton of power to move such a heavy car into the sevens. I just think there comes a time.........

I bought my Birdcatcher on eBay used and spent chump change for a rebuild kit---new O-rings mostly.


You might check with Steve Barcak. I think he has put port injectors on a BDS manifold. I think a bigger manifold is better, but a BDS can probably be made to work with some ingenuity.

Jim

Originally Posted by GTOGEORGE

Funny story about carbs and Roots Blowers......A friend of mine has a Roots Blower BB Chevy Dragster that runs Top/Dragster (Very Fast) any ways he at one time took the jets out of his carbs (2 - APD Alcohol Dominators) and he couldn't tell the differences........pretty funny!! Also adjusting the floats on them he said to put a piece of tape over the site glass window and raise the floats until they are pouring in the engine then start backing them off a little at a time when they stop then leave them at that........blower engines need a lot of fuel! True Story!


GTO George