Rfd 24-b Bb3 380 casting

quote:

Originally posted by gxp7903:
Well here's an update. I ended up going with a 632 steel block, guessing about 1880-1900lbs. same heads and cam as the 582.
first day out, brand new tires, 3000 ft air on a green track went best of 4.58 149, 7.26 180.9(only 1/4 runs ive made)
Next time out nothing changed on the car other than oil, 400 ft air maybe 50*, it did not like the first carb, went 4.62 popping a little. I switched carbs and added the biggest jet I had. went 4.58 again. the air went to 800ft next pass and it went a 4.56 150. So I need more jet for the good air. The following week it went 4.55 150. The conv is going to almost 6600, I still have other convs I can try, among other things.
So far I am happy with the results, out of the box on alky going 4.50s.

GXP, are you injected or carb? What size converterAnd who's?

carb. 9" Abruzzi conv in it right now. Only have about 35 passes so far with this engine. I have a couple hughs I want to try, and im going to try another one from marco.

you guys running 615s are you able to run a single alcohol carb with these engines?

Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

quote:

Originally posted by gxp7903:
Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

That sounds about right as far as ET goes. What carbs did you try?

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:
Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

That sounds about right as far as ET goes. What carbs did you try?

Alky: APD and BLP. BLP was the primary carb.
Gas: CFM

quote:

Originally posted by gxp7903:

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:
Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

That sounds about right as far as ET goes. What carbs did you try?

Alky: APD and BLP. BLP was the primary carb.
Gas: CFM

What size carbs? How did you like the apd vs blp?

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:
Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

That sounds about right as far as ET goes. What carbs did you try?

Alky: APD and BLP. BLP was the primary carb.
Gas: CFM

What size carbs? How did you like the apd vs blp?

All three were 1250s. All three were consistent. Hard to say that BLP was more consistent than APD, but I liked the BLP better all around.
BUT when the air got real good, the APD was 04 slower over the BLP. They were both tried on the same 40* day at about 200 ft corrected.
Other wise on an average day up to a real hot day, they were within couple thou of each other.

quote:

Originally posted by gxp7903:

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:

quote:

Originally posted by racerdude2054:

quote:

Originally posted by gxp7903:
Well after a whole season, I have tried a whole lot.
about 7 converters from 5 manufactures. Some shift points with different converters.
Little bubbas with beadlocks to Big bubbas non beadlocks, those ran the exact same on multiple occasions.
3 carbs, one being gas. I ran gas on a Friday, then back to alky Saturday, same track identical air, saw no difference.
I am now running 4.52-4.55 about all the time everywhere. Best Et to date is a 4.49(took 22lbs off the car).
I have even sprayed this thing for Q32s, 3 different converters, best of 4.39 on the bottle.

That sounds about right as far as ET goes. What carbs did you try?

Alky: APD and BLP. BLP was the primary carb.
Gas: CFM

What size carbs? How did you like the apd vs blp?

All three were 1250s. All three were consistent. Hard to say that BLP was more consistent than APD, but I liked the BLP better all around.
BUT when the air got real good, the APD was 04 slower over the BLP. They were both tried on the same 40* day at about 200 ft corrected.
Other wise on an average day up to a real hot day, they were within couple thou of each other.

Thanks for the info. You may want to try a 1450 gas, dont think you will see a night a day difference, but may be worth a try if you get the opportunity

We have a 632 HH motor with a 1450 that has ran a best of 4.53

who's carb is the 1450? have you tried a 1250, is so what was difference?
what does yours weigh?

quote:

Originally posted by gxp7903:
who's carb is the 1450? have you tried a 1250, is so what was difference?
what does yours weigh?

The 1450 is an APD, we have tried different types of gas with no difference in ET

We have not tried a 1250, we ran it on alcohol injection for a long time when we decided to switch to gas, the 1450 is what PAR recommended for us so it’s what we went with. We were not displeased with it at all so we have not tried anything else

Car and driver weigh around 1930

QUOTE]

The 1450 is an APD, we have tried different types of gas with no difference in ET

We have not tried a 1250, we ran it on alcohol injection for a long time when we decided to switch to gas, the 1450 is what PAR recommended for us so it’s what we went with. We were not displeased with it at all so we have not tried anything else

Car and driver weigh around 1930[/QUOTE]

I managed to get a couple apd carbs over the winter. One is gas 2.25 throttle bore Elite carb. The other 2.25 alky carb. There was basically no difference, with either lol.
and the alky carb shows a little of the same result as the billet 1250 carb I had last year- it slows up a little as the air gets good.

On a side note I went 7.17 @ 186 on the long track on alky when I made my TD lic runs. I was pretty happy with that.

Can you provide cam spec's?

quote:

Originally posted by Triple Nickel:
Can you provide cam spec's?

He never listed the cam, but it was from a 582, as were the heads, So it is probably not the optimum. It is a 632 now with a 582 cam and heads , and it runs pretty well, but a 380 cc runner head will never feed a 632 enough to run much past 72-7400. You could fake it some with a lot of intake duration, if the exhaust flow was decent. A 632 conventional head could stand upwards of 288-290 if not more.

quote:

Originally posted by Bad News:

quote:

Originally posted by Triple Nickel:
Can you provide cam spec's?

He never listed the cam, but it was from a 582, as were the heads, So it is probably not the optimum. It is a 632 now with a 582 cam and heads , and it runs pretty well, but a 380 cc runner head will never feed a 632 enough to run much past 72-7400. You could fake it some with a lot of intake duration, if the exhaust flow was decent. A 632 conventional head could stand upwards of 288-290 if not more.

I don't know the cam specs particularly, but I know it's pretty big.. and the heads are just based off of the Brodix BB3 Xtra 380 casting from what I understand, and could be a bit bigger than the actual brodix head..

The head just started at a 380 casting. I got the heads with the intentions of going bigger inchs. So bigger valve than stock, along with runners. The cam is not the same anymore as the 582 had, although not much different. the cam is 282/298 .900/.833. Probably not as much intake duration as you expected.
As far as spinning past 7400, when I had the looser converter in it(6750) I shifted it at 7600 and it was real close in et, about 01 slower, to current set up. so I think it spins just fine past 7400. How much more does it really need spun. Most basic bracket motors top out 7200-7300. So why twist it.
On the hose with only a 200 jet in it I shift it at 7600 with a little tighter nitrous converter and fell to about 6800, it went 4.35 159. Nitrous hits are on alky to.

Pm sent D...

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This message has been edited. Last edited by: 67TSCHEVY2,

quote:

Trophy

Would there be much et difference in the two engine combinations on Alky?