B1 AND B1MC

What flow numbers and hp are you guys making with these heads

They are good heads and I used both versions. They flow 410-430 intake side with B1 originals and make around 1000-1040 HP on 540 and up CI engines. The B1/MC's flow 440-455 intake side, and should make around 1040-1100 with the right combo and 572 or more CI. Compression should be 14.5-1 or more for the higher HP. If you want the mack daddy power, go Predator and don't fool around. They are capable of over 1200HP with flow #'s over 500 CFM.

Will be a bit of a squeeze in an AP Ian!

Those numbers are a little conservative, if the engine is built right. But yes, 1000+ hp is pretty common for B1 heads, either version.

LOL not for the ap it all ready has to much power for the old girl,this is going in a centura drag car.the b1mc we have are all over the place in port sizes etc.the flow seams crap for port and valve of that size, they had been ported by a guru in the states but the engine is down on power.

That is what i would expect to see 1000 plus this made 890 hp 775 ft lbs 432 cfm@800 with a 2.4 intake valve 272@800 on ex 1.780

Come get mine. If I don’t get busy on it soon it won’t make it out AGAIN this year

None of the flow numbers or HP#s matters. What matters is ET and MPH at what weight? As far as conservative, again I've had several of them starting at 470 CI to 572CI. I know what mine were capable of. I had a 1870# dragster with B1/MC's that went 7.25@183. I'm going to bet it made around 1070-1080 HP. The more HP you make, the converter you use is paramount to your success in using it properly. JMO Ask Al about his 525 CI B1/MC.

She should go alright and run some 7 s

I think hp and flow do matter when it comes to building a engine and trying to get the most out of it with comp and cam.but at the end of the day it is what it is and will make what it makes, then correct you need to have converter and gears right too and set the car up right to have et and mph from that power level

One of the last things I worry about is flow. The shape of the curve is important, as are other things. Flow is at the bottom of my list of importance.

If you are going to build a 1200 hp engine aspirated with a head that flows 350 cfm it is not going to happen but if your just going to build a 600 hp engine with 350 cfm heads it is going to be less important

Flow bench numbers matter so LITTLE that most of the top notch shops don't even bother giving that information, that's how much it matters. Ask Slawko what a given head he has done flows....As for HP potential depends on how much coin ya wanna spend. IMO an HONEST 1000hp out of a B1 original is not gonna be EASY to do. But absolutely it can be done. As for an MC MAYBE you can squeeze 1100 out of one if you spend enough money. Flow numbers really don't mean near as much as most people think. Hell if it was all about flow numbers my Predator would make 1300+ EASY..Unfortunately it don't work that way

I think what Tom is getting at his HP numbers on dynos and head flow numbers off of whomevers bench mean VERY LITTLE. Times slips, MPH and vehicle weight will TELL you how much power is being made. Regardless of what the dyno or flowbench states.

Just for giggles my 525" B1MC eventually went 171mph in a 2975lb car. So I will let you all tell me what kind of power it made. Our last B1 original in the kids dragster went 7.51 at 181 in Salt Lake at 8000' DA in a 1850lb dragster. We never got to run it all out anywhere else as my kid is only licensed to go 7.50. We did go 7.34 in Fontana with 14 degrees of timing pulled the entire run and using a small 2" 1050...Again you all can tell me what it made

100% true. The flow bench has its place and I think it's still a valuable tool. But it's still just a tool. There is so much more information you can get from a flow bench that aren't flow numbers it's silly.

Again, flow numbers are about the last thing I look at.

Well, all of you "PRO" racers might not think much about flow numbers, but from the end of the retail chain, that's all the info that is usually given to the final customer/consumer. It might not be the final answer to the HP question, but it will let you know if you are at least working with a decent head or not. Considering what B1's look like when purchased new, I would like to know what kind of numbers a given head makes once the ports are hogged out. Another thing would be to know consistency across all ports. Maybe highest numbers aren't that important, but knowing that all ports are done the same IS critical for performance. And for the money spent, I would want to see my heads flow close to the higher end, rather than the lower end of the spectrum. And yes, I would like to see mid lift numbers as good as possible, too.

I am retired at this point but, back in the day when I made a cyl head have better flow #'s ,99% of the time the car was faster, this has worked for me since the 80's, also the HP increase showed up on our old Gopower Dyno, I will say technology has passed me up but what I have done in the past has kicked butt on the track.

On heads I port flow numbers tell me what ET’s to expect and airspeed numbers tell me if there is more cfm on the table and where to go after it. My ears tell me turbulence and also when I see the cfm numbers backing up. Address one area and slow it down and check speeds again and you may be able to pick up more by attacking another area. I used to love flow testing

Take two identical sets of heads, both flowing 420cfm on the same bench. One done the old school way of a large by huge retangualr port opening, the other done with a more modern approach, taller, narrower port. There can be a LARGE HP potential between these two designs, yet both will pass the same amount of air. All I am saying is it aint ALL about a flow number. There is a lot more to making power than that. Just like a dyno its a tool, nothing more and they vary from place to place.

BTW I am no "PRO" racer, but I have spent many nights in Holiday Inns. Ive just fortunate enough to be around some very smart people near the top of the food chain in the sport and listen, watch and learn. Oh yeah having said all that I have a set of very nice CFE ported B1 Originals that need a home. Changed directions and don't need them now..

[color:#FF0000][/color]


Wallace=1212fwhp. ////Moroso less.

I have 2 drag cars,1-500 ci /400,1-440,both big roller ,both has originals,both in lite weight darts,cant get them to run no faster than,6.20s in 1/8.i had a 440 that had b-1 mc heads,it ran 5.70s,my indy 440-1 and indy sr heads ran better,plus weight less,b-1 are very heavy heads

Are you really saying that your -1 and SR heads made more power than B1/MC's? If so, something was very wrong.

I've dyno a bunch of different motors, street and strip as well as race only, all of them made better power with better heads
I tested two different sets of heads on two of my motors, one set of SR with M.W. ports that flowed 350 CFM at .700 on the intake side, one set of CNC ported 440-1 that flowed 370 CFM @ .700 on the intakes, both heads had 76.0 CC chambers. The SR made 727 HP on my 518 C.I. pump gas motor, the 440-1 made 775 HP using the same intake, carb, camshaft, ignition timing and pump gas.
The 526 C.I. bracket motor made 775 HP at 7000 RPM with the SR heads and it made 845 HP with the 440-1
I built one 543 C.I. B1 headed bracket motor and it made 920 HP on a different dyno in Boise, ID. Those heads flowed right at 420 CFM at .700,.800 and .900, the lift at the valves was.720
More air on most Mopar V8 = more HP usually

I hate to say this but if you had a big block mopar with B1 heads on it in a lite weight Dart and it only ran 6.20's I wouldn't tell anyone. I would put that info in the vault and lock it up. LOL. My buddy's Duster runs 5.80's with Edelbrock heads.