BBC thoughts

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statsystems
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Re: BBC thoughts

Post by statsystems » Wed Aug 16, 2017 6:41 pm

MadBill wrote:
statsystems wrote:...The exception would be the cross ram. I love those things. If I could find one that I wouldn't have to send my wife into whoredom to afford I'd do another one. They take some work, but they will work.
Like this?
David Vizard and others say that stock, the dual plenum designs like mine here (previously converted to Lucas timed MFI), have terrible distribution/resonance issues, hence I'll fabricate a much larger balance duct for A-B testing when I get my 498" BBC together.

DSCN2256.JPG
I don't recognize that intake. The intakes I used all had removable tops.

That's pretty cool right there. I'm trying to remember if the 302 chev CR had a removable top. Been years since I've seen one.

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Re: BBC thoughts

Post by prairiehotrodder » Wed Aug 16, 2017 6:57 pm

The Word of God is quick and powerfull
www.therocketshop.blogspot.com

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Re: BBC thoughts

Post by F-BIRD'88 » Wed Aug 16, 2017 8:40 pm

prairiehotrodder wrote:Hey F-bird
where do you live?


https://www.kijiji.ca/v-view-details.ht ... stSource=b

Dam, Brockville Ontario is far away, way on the other side of Lake Ontario from me. (A 5 hour drive...

But give 'em a call or email. It's big, but not heavy to ship to you....
ya struck gold...

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Re: BBC thoughts

Post by MadBill » Wed Aug 16, 2017 10:21 pm

statsystems wrote:
MadBill wrote:
statsystems wrote:...The exception would be the cross ram. I love those things. If I could find one that I wouldn't have to send my wife into whoredom to afford I'd do another one. They take some work, but they will work.
Like this?
David Vizard and others say that stock, the dual plenum designs like mine here (previously converted to Lucas timed MFI), have terrible distribution/resonance issues, hence I'll fabricate a much larger balance duct for A-B testing when I get my 498" BBC together.

DSCN2256.JPG
statsystems wrote: I don't recognize that intake. The intakes I used all had removable tops.
That's pretty cool right there. I'm trying to remember if the 302 chev CR had a removable top. Been years since I've seen one.
The name's been ground off; I keep meaning to track it down; I think it might be an Edelbrock XC96.

The GM factory cross ram was two piece, with a single plenum. I put one on my 1970-1/2 Z28; ran awesome!
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.

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Re: BBC thoughts

Post by F-BIRD'88 » Fri Aug 25, 2017 4:17 pm

Did you inquire on that Victor Ram yet?

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Re: BBC thoughts

Post by bigjoe1 » Fri Aug 25, 2017 4:32 pm

When I put a T Ram on an engine similar to yours, it PICKED UP ALMOST 100 HORSEPOWER- The minimum you could get would be between 50 to 70 MORE HORSEPOWER



JOE SHERMAN RACING

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Re: BBC thoughts

Post by prairiehotrodder » Fri Aug 25, 2017 5:06 pm

F-bird - The guy in brockville won't ship it to me. I've emailed him 3 times. He also won't give me his phone number. I found a Weiand one as well but not having any luck on it either.

I also talked to John Dickey at AED and he will build me 750 tunnel ram carbs for $699 each. At first he quoted $999 for ones that had a bunch of CNC work on them but I think the cheaper ones will meet my needs. I am not in a hurry because the season is almost over here and it will be a winter project. I hate overpaying on freight and exchange rate so i'll just wait for the right deal. I may by a TR used but i'll buy new carbs.

I hope to make it to the track one more time and test my latest changes
- electric fan
- electric water pump
- advanced cam to 103 ICL
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Re: BBC thoughts

Post by F-BIRD'88 » Fri Aug 25, 2017 6:09 pm

I don't see the value in overpaying for the specialized/boutique branded carbs

that you WILL HAVE TO tune for your car anyway.

You will save a bundle by building and tuning your own custom carbs yourself

Then spend the money on Dyno tuning. You will come out way ahead perf wise
and spend less money.

For your street/strip purpose car consider using 2 Holley/Demon Street Demon 750 carbs
on a T ram. That you can dial in yourself....

I have a friend here that has been running 2x Eddy 750 AFB's on his t rammed Big Block Mopar
(that makes well over 750HP) Has not touched the carbs in 12 YEARS.

These were dyno tested and tuned against very well sorted out Holley tunnel ram carbs
on the dyno. The holleys while they did make a bit more power, DID NOT make enough more power to justify the BIG DIFFERENCE in cost..

This car runs a very low 9sec et and would run a 8 sec ET if it had the right transmission.
He is the opposite of you his car needs a 2 speed Powerglide but he likes his all Mopar 727 3 speed trans. (has to launch it in 2nd gear)(#2300 ish car)
I saved him a ton of money on the AFB carb choice advise and the dyno and track and street testing proved it. If you don't like AFB's try the "Street Demon" carbs.

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Re: BBC thoughts

Post by F-BIRD'88 » Fri Aug 25, 2017 6:12 pm

Will be interesting to see the track ET effect of getting rid of the engine driven fan and Water pump and having moved the camshaft.

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Re: BBC thoughts

Post by prairiehotrodder » Fri Aug 25, 2017 11:33 pm

ok if i did buy a couple edelbrock 750's (#1407) where would i start as a baseline ? Like what needs to be done to them for a TR application?
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Re: BBC thoughts

Post by F-BIRD'88 » Fri Aug 25, 2017 11:53 pm

Start with the stock default jets and rods. The power piston step up springs may need to be changed so it can idle (in gear). Install a weaker tension step up spring spring. These carbs do not like a lot of fuel pressure. 5.5 psi is great.

I asked my friend all long time ago what he ended up with for jetting on his 2x 1407 eddies after engine dyno testing.
He did not remember specificly but said it was not a big radical change.
Then when installed in the car and on the street thru his 4 mufflers he find tuned the
primary metering rods a bit leaner from the dyno jetting for when the motor is fully warmed up.
Using a Innovate wide band ...

All he did was remove the 2 choke flaps on his. You can start with yours installed.
Even 2 borrowed 600 eddies will prove the point if you don't want to invest yet.
Avoid the 500's if max power is the goal. There is nothing wrong with them. They just won;t make as much power as the larger ones.
2X 800 Edelbrocks are NOT too big on that motor.

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Re: BBC thoughts

Post by F-BIRD'88 » Sat Aug 26, 2017 12:00 am

You are a welder so you could build - fabricate the 2x4 carb adapter to run the 2 carbs on your current single 4 bbl intake to see the effect,, before investing. You will get the idea and get a handle on 2x4 carb tuning.
(And have some fun too. ) Got 2 carbs kicking around?

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Re: BBC thoughts

Post by prairiehotrodder » Sat Aug 26, 2017 12:04 am

don't tempt me.

i have about 10 Q-jets. I can't get motivated to do anything with them.

I think i'll keep moving in the TR direction and keep my eyes open over the winter.
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Re: BBC thoughts

Post by F-BIRD'88 » Sat Aug 26, 2017 1:10 am

"10 Q Jets" ha hha you're all set... ;-) You only need 2 of them and you'll have a ton of spare metering rods and jets which you can customize those yourself to get a "range" of jets and sec rods to try out.
Picture 2 Qjets mounted back to back on a 2x4 carb adapter on your super Vic...

On the Qjets (2X4) it will all be about the dialing in of the secondary metering rods and hangers
for best WOT. power jetting... All that is done from the top... on them...
These carbs also do not like a lot of fuel pressure.

Beyond the WOT jetting (Secondary rods and hangers selection)
The low speed and "drive" is all in the primary jets and rods and the adjsutable "APT"

But then.... you fine tune tweek it all by making use of the PCV valve ports on the carbs to
create a adjustable air bleed(s) "idle eze" to both tweek the idle and it also tweeks the whole fuel curve
ALSO.... (much like tweeking the emulsions and HSAB's in a holley, except easy and basic, just +/- the bleed rate of the PCV as needed)... The carbs don;t know or care if the PCV is actually hooked to the valve cover or not... When you get it all finalized the 2 SUDO PCV hoses with restriction hook up to the air cleaner.
(Can be nice braided lines) Its your lil secret as to what they actually do...

this is what lets you get the primary throttle blades in correct idle position at idle on the 2 Qjet carbs
for the right idle rpm and the correct throttle opening at idle with the 2 Q jet carbs.

If you have another ///any V8 ///mule test motor/car on hand you can do 90% if the initial setup of the 2 carbs on a 2x4 adapter , first.... then move it to your 540BBC for final dial in tuning.

If you just don't like it, stick the 2x Qjets back on the shop shelf and give the 2x4 carb adapter to the wife to use as a flower pot....
You can try/set up the carbs first, mounted inline.... then try them mounted back to back for effect....

You can make up a prototype////test 2x4 carb adapter out of thick sheet metal and a few aluminum or wood carb spacers. I'd make it about 3.5" tall.... plenty of transition slope in the adapter....

You can still do the tunnel ram too....
You could end up with 2x Qjets + 2X Edelbrock AFB's and 2x home built custom Holley 750 HP carbs
all set up for on a tunnel ram (or the 2x4 adapter) AND STILL have less money invested than if you just bought 2x $699 tunnel ram carbs.

ALL these will work real well once dialed in... And it will keep you plenty busy in the shop all winter
playing with it.

if you can dip a carb metering rod into a lil pot of HOT melted solder and file it to size you can make your own custom carb metering rods for test/tuning.... (dip the hot metering rod tip in soldering flux first then dip it in the solder to build up the tip diameter)(file to size)
You only need a "range" of 4 to 5 pairs of secondary metering rods for each Qjet.
and say 4 sec hangers You make them too.

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Re: BBC thoughts

Post by F-BIRD'88 » Sat Aug 26, 2017 1:32 am

If you make up your own custom made drop base dual quad air cleaner and carb scoop assembly the drop type custom air cleaner base will cover up the 2 carbs on the motor and no one will be able to tell they are 2 Q jet carbs or 2x edelbrocks or 2x 750HP (Built by PrairieHotrodder Carbs inc) Holleys

Paint the fiberglass areo "shaker" carb scoop the same colour as the car.

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