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View Full Version : Need help on BBC alcohol tune.ROOKIES


olds48
05-21-2008, 01:12 PM
My buddy has a FED with a port injection Ron's toilet bowl on it.We are having a hard time leaning it out.It is extremely rich.Milks the oil completely on a 2-3 minute warm-up.We run water in the block so as to have a temp reading.Takes about 2-2.5 minutes of idling to hit 140.Goes thru water box at 140,light burnout and still at 140.Kill time staging(we notify the other lane of our problem :D )and creep it up to 160-170.Make a pass(1/8 mile) and it might see 190.

468 BBc
12:1 static comp
B&M 250 Powercharger putting out 12-15 lbs of boost
Edelbrock heads
Cam is Solid roller with specs around 660 lift and 260 [email protected]
Exhaust is zoomies

Toilet is setup with a 80A pump
feed and return lines are both 6 AN and are under 4 ft long each
nozzles are 37
Pill is 80

We tried a 90 pill but line pressure dropped so bad that when we burped the throttle to check the barrel valve it would spit fuel out of the nozzle(around the sponges/air bleeds).It made no boost at any rpm in nuetral with the larger pulley and we had no problem with spitting,but were rich.Wanted to try the smaller pulley(12-15 lb boost) and figured it would help lean out the engine.That pulley would make 3 lbs boost just revving in nuetral.That is when the spitting started.We put the 80 pill back in and still spit too bad.Put big pulley back on with 90 pill and it spit.Only way that the line pressure is high enough to overcome the spitting is with an 80 pill.But then we're rich.Seems we need a nozzle change,but Ron's says to run what we got and just tune around that 80 pill and keep with the 37 nozzles.

BTW.We zoomie for #6 feels cold but plug looks consistent with the rest.Also,entire left side(cyl 1,3,5 &7)feels alot cooler than the other side.????

Thanks for any info,we are both new to alcohol.He can have it,I think I'll stick with gas :D

olds48
05-21-2008, 01:33 PM
I messed up.It would do fine,and not spit,with the big pulley and a 90 pill,but was still rich.90 pill and little pulley would spit back.How much should you adjust with the pill before giving up and trying another nozzle?When we went from the 80 to the 90 pill we picked up .03 and 5 mph but were stil way off what we had before.Car has ran a best of 5.17 at 140 mph.Were stuck in the 5.30s now. :(

OneBadGMC
05-21-2008, 09:48 PM
Barrel valve is too fat. What's the leak down set at?

olds48
05-22-2008, 08:28 AM
Barrel valve is too fat. What's the leak down set at?

I'll have to find out about the leak down.I know that the Rons system has a built in check valve on the return line,nonadjustable at 3 psi,if that is what you mean.You think it could just be in the barrel valveand not the pill and nozzles?

LuckyDawgRacing
05-22-2008, 01:03 PM
Oh boy! You're trying to tune and you aren't using a leakdown gauge, Weeeee, are you in for some fun!

olds48
05-22-2008, 05:50 PM
This is my buddies car.He has all the fancy toys,we just don't know how to read 'em :D

OneBadGMC
05-23-2008, 09:26 AM
Schooled you on carbs... Guess it's time to get schooled in mech injection.

How to leak down a BV using a 2 gauge tester:

1. Block off all injector lines & returns except for hat nozzles
2. Connect dual gauge tester to outlet of compressor
3. Set Air Compressor to read 100psi on 1st gauge
4. Connect tester to inlet of barrel valve
5. Read % on 2nd gauge

A good starting point for a blown motor is going to be 25% on a dual gauge. 75% on a single gauge tester.

Now, go buy this book: http://racecarbook.com/firs.shtml

olds48
05-23-2008, 02:25 PM
Schooled you on carbs...

:shock: :?: Thanks for the info on the leakdown!!

olds48
06-08-2008, 10:42 AM
Got the leakdown set,leaner than Ron's reccomends,but seems to be working ok.Thanks for all the info.How do ya'll run your returns?To the tank?Pump inlet-tee?What works best?Also,who makes the best crank trigger?Thanks again!!

OneBadGMC
06-08-2008, 12:05 PM
You realize that the leak down is just a base, and that you'll have to change it 2-3 times every day, right?

Start the motor, loosen the screws, fatten it up until it surges, then lean it back out just until the surging stops.

As for plumbing.... See below.

http://i204.photobucket.com/albums/bb199/onebadgmc/IMG_0762.jpg

hammertime
06-08-2008, 02:36 PM
You realize that the leak down is just a base, and that you'll have to change it 2-3 times every day, right?

Start the motor, loosen the screws, fatten it up until it surges, then lean it back out just until the surging stops.

As for plumbing.... See below.

http://i204.photobucket.com/albums/bb199/onebadgmc/IMG_0762.jpg

I've got to ask why change it 2-3 times a day ??

Once you get it set the only change you should make all year is a pill change from hot to cold or cold to hot weather ??

I run return straight to top of fuel cell, crank trigger MSD.

OneBadGMC
06-08-2008, 05:03 PM
I've got to ask why change it 2-3 times a day ??

Once you get it set the only change you should make all year is a pill change from hot to cold or cold to hot weather ??

I run return straight to top of fuel cell, crank trigger MSD.

Barrel valve leak changes with the weather, just like the main pill does.

I take it you don't own a weather station.

hammertime
06-08-2008, 05:43 PM
I've got to ask why change it 2-3 times a day ??

Once you get it set the only change you should make all year is a pill change from hot to cold or cold to hot weather ??

I run return straight to top of fuel cell, crank trigger MSD.

Barrel valve leak changes with the weather, just like the main pill does.

I take it you don't own a weather station.

I do .. mine stuff doesnt get changed at all, all year. Toilet or Terminator must be I am just lucky. I know NO one who changes the BV once they get it set where the car likes it. I dont even change the pill in my setup its good either way. Spring Weather to Hot Summer weather no change 7.55 in spring 7.55 in hot guess I got lucky. :D

OneBadGMC
06-08-2008, 06:10 PM
Rather be lucky than good anyday.

hammertime
06-08-2008, 06:13 PM
Rather be lucky than good anyday.

ahmen to that :lol:

us7race
06-09-2008, 02:15 AM
You realize that the leak down is just a base, and that you'll have to change it 2-3 times every day, right?

Start the motor, loosen the screws, fatten it up until it surges, then lean it back out just until the surging stops.

As for plumbing.... See below.

http://i204.photobucket.com/albums/bb199/onebadgmc/IMG_0762.jpg

What do you know on a High Speed Lean-out? :wink:

OneBadGMC
06-09-2008, 07:43 AM
What do you know on a High Speed Lean-out? :wink:

I know if you don't set it right, you can plan on buying new pistons. :wink:

Do you have a more specific question?

us7race
06-09-2008, 07:21 PM
My buddy has just added one and I figured I'd ask. He is going to start out with the smallest pill and go from there. His EGT's on a couple of cylinders were down to around 300 still ran 6.52 @209 in the 1/4.
I think it was a 4.19 in the 1/8 on a not the greatest track..his 60' was off from .980's to 1.0's. so Hopefully with more seat-time in the car and the high speed lean-out can go 6.40's or better..

OneBadGMC
06-09-2008, 09:44 PM
My buddy has just added one and I figured I'd ask. He is going to start out with the smallest pill and go from there. His EGT's on a couple of cylinders were down to around 300 still ran 6.52 @209 in the 1/4.
I think it was a 4.19 in the 1/8 on a not the greatest track..his 60' was off from .980's to 1.0's. so Hopefully with more seat-time in the car and the high speed lean-out can go 6.40's or better..

Try this site: http://dragracemath.jimhatleyracing.com/fuelsys.html

Should help him setup the high speed if he knows what he's looking at. :D

OneBadGMC
06-11-2008, 08:32 AM
I've got to ask why change it 2-3 times a day ??

Once you get it set the only change you should make all year is a pill change from hot to cold or cold to hot weather ??

I run return straight to top of fuel cell, crank trigger MSD.

Barrel valve leak changes with the weather, just like the main pill does.

I take it you don't own a weather station.

I do .. mine stuff doesnt get changed at all, all year. Toilet or Terminator must be I am just lucky. I know NO one who changes the BV once they get it set where the car likes it. I dont even change the pill in my setup its good either way. Spring Weather to Hot Summer weather no change 7.55 in spring 7.55 in hot guess I got lucky. :D

Just because I thought of it... Aren't you running a normally aspirated motor?

hammertime
06-11-2008, 08:52 AM
I've got to ask why change it 2-3 times a day ??

Once you get it set the only change you should make all year is a pill change from hot to cold or cold to hot weather ??

I run return straight to top of fuel cell, crank trigger MSD.

Barrel valve leak changes with the weather, just like the main pill does.

I take it you don't own a weather station.

I do .. mine stuff doesnt get changed at all, all year. Toilet or Terminator must be I am just lucky. I know NO one who changes the BV once they get it set where the car likes it. I dont even change the pill in my setup its good either way. Spring Weather to Hot Summer weather no change 7.55 in spring 7.55 in hot guess I got lucky. :D

Just because I thought of it... Aren't you running a normally aspirated motor?

http://i203.photobucket.com/albums/aa306/Dragster387b/100_1592.jpg

olds48
06-18-2008, 12:55 PM
Hey Hammertime.Those look like Moroso Super 40 wires.You like those pretty good?BTW ,thanks everyone for their help,once we got the leakdown right,everything else kinda fell in line behind it.THANKS EARL!!

hammertime
06-18-2008, 01:17 PM
Hey Hammertime.Those look like Moroso Super 40 wires.You like those pretty good?BTW ,thanks everyone for their help,once we got the leakdown right,everything else kinda fell in line behind it.THANKS EARL!!

Them are the blue spirals the step below the ultra 40's. I had the ultra 40's last year both are good wires.

suicidebomb
06-19-2008, 11:08 AM
Hey Hammertime.Those look like Moroso Super 40 wires.You like those pretty good?BTW ,thanks everyone for their help,once we got the leakdown right,everything else kinda fell in line behind it.THANKS EARL!!
You're most welcome Olds48 :D

olds48
06-19-2008, 01:11 PM
Thanks Hammer.Thanks again Earl :D

hammertime
06-19-2008, 01:13 PM
Thanks Hammer.Thanks again Earl :D

not a problem .. :D

suicidebomb
06-19-2008, 03:01 PM
Glad I could help, :D