Have a 440 with stage 6 heads. Porter redid the heads and they look and work awesome. Cam is Hughes cam duration is 282 intake 251 exhaust.lift is 613 intake 626 exhaust,12.7 comp, 4.56 gears, 8 inch a-1 converter. with trans-brake.Car is a consistent 1.52 60 ft times. Car will run 10.70 at 126. Need intake with better bottom end. Car is 67 Barracuda that weights 3300 lbs.mono leaf with Cal Tracs and Rancho 9 way rear and 90 10 fronts

What intake and carb are you running now?

Can you correct your cam specs for us. Don't know what you have.

Are you stating 282 Advertised for intake and 251 @ 050 for exhaust?

Rick, check those cam duration numbers again.

I don't recall if you have 1.5 or 1.6 rockers.

Aside from advancing your cam I am not sure what you can do but see what intake,carb you have.

Stage 6 and SULLENS E85 850 HOLLEY

282 AND 251 ADVERTISED. AT .050 IS 252 INT 257 EXH

Do you have, or have access to the adapter plates?

THEY ARE 1.6. BEEN GOING TO CALL YOU AND TELL YOU THANK YOU. THOSE HEADS MADE SUCH A DIFFERENCE. CAR PULLS HARD IN HIGH GEAR.

Adapter plates for?????

I thought you had the stage 6 intake for use with those heads on the RB block.
To use a "normal" intake you'll need the spacer plates.

Probably wouldn't help with the bottom end situation, but if the cam is only 252/257 @ .050, there is some power to be gained from going bigger.

Converter is 8", but what does it stall to on the brake with no chip?

I think fast is in th right track...sounds like it needs more converter.

I have no idea on the stall. I have never checked it like that. I have have stepped on the throttle with the footbrake and i think it went to around 3800.

You can check it one of two ways......(motor and trans warmed up of course):

-Engage the transbrake, floor it with no chip in the two step(if you run one).
Hold it long enough to get a good reading(like 2-3)seconds.

Or

-with the car rolling along at about 10-15mph in high gear, floor it and observe where the tac levels off.

You really want it to be at least 4500rpm for that application.

IMO, this needs to be a known quantity before any other changes are made.

i've become more impressed with my Stage 6 heads lately. mine are on a 400 block with max wedge intakes i use a Super Victor intake. in my 'cuda the engine keeps running in the 10's which is a no no because i'm not teched. the 950 carb is backed off to the point the secondaries are only just opening & the timing is reduced to 30* total & yet yesterday with brand new MT et drag radials it went 10.93 again & had me banned from the track. i guess i'm going to have to buy some more safety gear.

Stage 6 heads don't get a lot of respect but a good Friend of mine has gone lots of 9.70's at Keystone with them in his beautiful street legal duster. He did his own porting work

you can check the archives here and see where my stage VI's were. I ran the old tried and true Ultradyne NF 69 277@.050 .640 valve lift 304 duration at .020. (1.5 ratio rockers) RB based 4.15 stroke (welded and stroked I might add), LY rods, Ross pistons. Had the shift light set at 5800 and ran a string of 9.91's at Famoso before I sold it. 9" converter, but I can't recall the stall. Funny thing about that mill.... I noted for a couple years that I'd run quite well in the 1/8th, but would often get drove around on the top end in the 1/4. This was with a 4150 M1 with spacers and running a Holley 850 carb. Finally ponied up for the 4500 M1 RB intake (no spacers) and an Ebay Carb Shop 1050 dominator. Picked up like .4-.5 in the quarter and the trap rpm went from 6200 to 6900. Pulled the 4.56 gears and went with 4.10's (29.5 tall slick) and went even faster yet! That thing was a low rpm tractor engine that some how is still alive. The guy I sold it to was well informed of how wore out it was, but he ran it for a season before selling it. I understand it's still running.

Nice Duster!

My wasn't directed at you; I just threw that on here since I've got a good bit of experience w/ Stage VIs and was (am) curious where the topic goes.

FWIW, to the OP...
1. The MP Stage VI 4150 intake (RB w/o spacers) needs a LOT of work to "work", and even then has some drawbacks. It's really a poor match for your combination, especially w/ that small of a cam.

2. There is a vendor on eBarf that reproduces the MP RB intake spacers and has one (1) set left listed as of this post -> CLICK THIS

3. The "If it was mine..." answer is:
- Pull the heads, if not already off
- Get those spacers
- Have the spacers mounted to the heads & the heads' roofs raised from the top of the spacer through the intake port in a line-of-sight approach to remove the dip in the roof where the spacers match the heads
.


- Get a Victor 440 intake and do the plenum mods I've posted on here in the past (assumes you have no issue running a taller intake)
- Get a bigger cam; Hmmm... why not let Dwayne spec you a cam, too, since he just prepped your heads?

4. And what everyone else said about figuring out what your converter's stall is... But I suspect -- as long as there are no issues w/ the converter -- the current intake manifold has such a "hole" in the torque curve that it's not doing your 60-ft times any favors. You're .07 slower in the 60 and .2 slower in the 1/4 than I ran at the same MPH.

Carry on.