Old brodix -10 heads on a 406 keep them or buy new??
 

Hay what do you guys think, new heads or keep the old??? It just wont run like I think it should. here is wat the motor has. the heads are old -10 spread port brodix heads flowed buy rons racing, 2.10 in 1.60ex (intake gaskets felpro 1206). the cam is a lunati 276/284 at .050, .640/645. victor e itake ported to the heads, flat top pistons witha .014 deck, .039 gasket, heads have 60cc chambers, 850 carb, powerglide trans with brake, 5100 stall converter. the car is 8" tire 2700# vega (with me). 26" tall tire with a 373 gear. the car run 11.20's @ 118 to 124. bad short time of 1.7's (not spinning). I have used 3 dif converters this one is made for the car. I have used a rpm airgap. I think the car should run in the mid 10's. It feels like a dog.
More info . I had the converter make to stall with my combo at 5100rmp on the brake. I told the guy it should make about 500hp. the convert stalls at 5150 on the brake. Am I off here?????? I dont know what else to try. Thanks Billy C

TRY A 28 INCH TALL REAR TIRE AND A 4.56 GEAR,I THINK THE 3.73 IS TO SMALL.
JUST MY 2 CENTS WORTH....

Gear change and a looser converter would help it 5500ish 8"

I was thinking it could use a little more gear but I cant get a bigger tire under it. I have in the past changed gears up and down and it has never made that much diff. I have had many race cars but always bbc , as fast as 8.06@170mph. this has me stumped. Thanks bill c

I have had a 5600 stall converter and a 4300 converter in it. Ran 11.20,s with both. I would think if the gears were to high it would mph much higher. Thanks Billyc

That car is way off, i'm thinking also it should run 10.50's. I can only go by comparison, my friend Jimmy Smith, ran 6.80's crosses to a 10.80, with a 355 flat top, @ 3,000lbs, i ran 10.80's with a 406" @ 3250lbs, both of use have 60's in the mid 1.40's and we both run .625's to .640's lift cams with 106 l/S installed at 102* i have Brodix T1's and he has the old pro top line heads.
He now runs alcohol and can run 10.50's / 6.50's, i now run alcohol with a 377" and have run 6.52 and 10.59 @ 125 mph.
I think that's the same cam that Jimmy has in his car if it's has the 106 lobe seperation.
I'm asumming you have 1 3/4" or 1 7/8" headers, also i looked up the gear ratio with your tires. If you run 124mph, @ 7,000rpm's you need a 4.37 gear, at 118 you need 4.59 gear. It almost sounds like the cam is off, did you degree it in? because it doesn't have the bottom end torque it should have.
I also have a set of old Brodix 10's RP-FP heads and they flow 314 CFM at .700 lift. i have run them yet but i have them on the 434" motor that's going in my Malibu.
I don't know exactly what's wrong but something for sure is not right, but i'll bet the problem can be found.

JMO

Zip.

Yes the cam has the 106 lsa degreed in at 0. the headers are 1 3/4" I had a nother cam in this thing also 102 lsa. set 4 advanced and at 0. with .630 lift. I know if i did set it at 2 advanced it would not make that much up. I also have had the whole motor apart this summer and everything in a new fresh block. No change. I am about to sell it and go back to a stock head 454 and it will run faster. I would think this thing should run good with these heads. one of my buddies had the same heads on his 80 glass body race truck same motor ran high 9,s all motor and low 9,s with N20. Thanks for the help Bill C

The only difference i see between the motors that Jimmy and i have to your motor is the compression ratio, with my 406" i had 12.5 to 1 with the track1's and Jimmy has 52 CC heads with flat tops, so his compression is probably close to 12 to 1. The 377" i have in the car is 14 to 1.
Don't know but compression might wake it up, that would be the cheapest way that i can see, around $500.00. If you have some scales you can match the pistons to the weight of the one's you have in the car without having to rebalance the crank/ whole engine.

Your heads are almost the same as i have except i have 58 CC chambers and 2.140 intakes, which will make my 434" about 15.5 to 1, but it's will be on alcohol stacks. I surely hope i don't get surprised with them (heads)
not working good. I am running a much bigger 4/7 swap cam in it.

Zip.

How are you finding the actual stall ?

What brand conv's and size ?

I agree with Zip, more compression ought to wake it up a bunch.

Just curious since you didnt mention it >How much total timing are you running?

Dont be afraid to crank it on up there to the 39/40 mark with good fuel, that will give it more off the line grunt, something desparately needing.

Once again as Zip suggested the cam could be killing it.
Advancing it a couple degrees will improve torque down low.


As a comparrison : The boys 89 GT mustang (heavier) with a 351W and a small hydralic flat tappet cam and a few other mild mods sixties foots in 170's, mind you this car has a stock converter, nine inch slicks and 373's.
Best 1/8 ET has been in the mid 7.40's

With more compression/ cam timing and a steeper gear (456/488) - you should easily see mid 10's.

Goodluck and let is know how it goes, Cp