He built a big inch SB for a friend and it was a giant pile of cr@p. My friend got lured by the engine master thing and was absolutely hosed. It was like 13K+ IIRC. The machine work was HORRID.

Bryce Mulvey ("Dr. J") appears to be part of of Steve Dulcich's "Good Old Boy" network and seems to get lots of magazine coverage as a result. That's disappointing if the quality of the work fails to meet the hype...

The interesting thing about intake manifolds and ports is that any given intake valve is SHUT roughly 2/3rds of the time...that's why it takes ~ 4 times the amount of gross airflow through a runner to net 1/4 of that amount into the cylinders.

After 30 years I've got a semi grasp on reflective wave tuning, intake pulses and how cylinder sizes and valve timing effects a few different manifolds and maybe a bit more about the tuning effects of different runner lengths... but that's about all...just a grasp. Most of what we know about what's going on inside an intake plenum is still "cause and effect" results.

The technical portion of this thread reminded me of a PM I'd received from another member about a year and a half ago when a similar discussion was going on. The source said they didn't bother to post this since it would have probably just resulted in a ... This has been scrubbed of a few things, but the majority of the pertinent information remains.

"I'm not a huge believer of intakes being overly restrictive to flow #'s. Case in point I had a motor running in a customers car that had a set of heads that flowed ~375 on my bench. We ran it at track on same day with 2 different intakes, One flowed around 330 max per runner on my bench, the other in the low 360's. Car ran virtually identical ET's with both intakes. I took the 330 cfm manifold which was pretty much just a port matched deal, & reworked it so it would flow ~370 per runner. Back on car... ran same as before when it was 330 cfm runners.

I've done a bunch of testing of intakes bolted to heads on the bench & never found any power playing with that stuff. You'll never bolt a manifold on & have the head stay same or pick up flow, unless the short turn in head is screwed up, in which case the manifold being bolted on may help slow airspeed down enough to keep ST stable & then #'s will go up. It doesn't matter how good the manifold is, the head will lose airflow with a manifold bolted on. It's a restriction, plain & simple even if it doesn't LOOK like one.

I'm not saying you can't make gains or even decent gains with working a manifold, I'm just saying I wouldn't get caught up in flow #'s. If the runner CSA/taper & plenum volume is correct for the head CSA/volume & engine size & intended RPM range, it will run good and make good power."

I am running stage 3 CNC ported victor 440 standard ports heads from hughes. I have used a super victor manifold ootb and then sent it to dave for a full CNC port while using race gas. I really didn't see any E.T. gain until i switched to methanol in which i gained a half second. hope that helped answer you question if anybody has done that..

From what I've seen on the dyno, a really bad intake will cost a bunch of power. A really good intake will add a slight amount of power.

Most modern intakes are fairly good right out of the box but there is always some room for improvement.

FWIW (not much ), I figured it's time to "lock and load" the Makita and get back to on my M1 before I drop any more $$$ on buying another intake. (Yes, I know that's really a SawZall, but I don't see a die grinder emoticon in the options available.)

I was giving it the last night and still think it should do the job OK, even though it's going to take a good bit of work to open it up to match those CNC Victor's. I suspect the hardest thing is going to be making sure there's enough CSA through the length of each runner, since the M1 has some rather significant taper between the plenum and the head.

Brad,

Why not try the 337? the as delevered ports are nowhere near MW, in fact the ported SD I ran on my 508 had bigger ports at the head mating surface. I can measure them when I get home but I think they're really close to what your heads are but the runners are way bigger from the plenum than the RB M1.

I was worried the 337's ports would be MW sized at their entry in the plenum and kill off too much velocity for a 440. That's one of the drawbacks to that Stage VI intake that Roger Helgesen did for me... ran really strong from torque peak up to HP peak, but had a big dip in the curve below the torque peak because the runners were really too big for a 440, IMO. I haven't seen a 337 up close to be able to measure the runners, so I'm taking a s.w.a.g. that the same thing would apply.

Wow... deja vu all over again: An Old 337 Thread

Oh yeah, well I think your answer is the 440-2D with a port match and a bit of lower plenum massage.

Mine's already full blown maxie or I'd let you try it, bringing the lower plenum flows in line with the uppers is probably worth at least 20 hp and I know it outflows an M1 or a Victor. I guess some people think you can have too much torque but if you get more down low and as much or more up high, I think you go faster. You can try the 337, I haven't touched it so you're welcome to port match it to yours...mine needs to go full MW anyway so you'll be doing me a favor

I guess if i'm being honest I've been having a small block 'affair' for the past year or so, I'll go back eventually though I always do!

I do have a Indy dual plane that has been port matched that I could sell you. I'm sure I'll be able to buy it back in a year when you decide to go a different way! The UPS guy is making money running parts back and forth between us.

Andy,

Do you think you could modify a 2D on a bridgeport to fit a 4500 by milling the existing flange/base? (i.e., without having to weld a new raised flange on top?). Looks to me like there's enough meat there to work with.

at >360cfm average flow per runner (fully ported)it outflows most singles, what holds it back is obviously a dual plane needs a bigger cfm carb to make up for the lack of an open plenum (where all 4 barrels can feed one runner). The only 4150 option that's much bigger than what I got (~1040cfm per Patrick at P-S)is the 1 barrel SV1 and I don't know how that could work on a dual plane.

Brad, I verified the 337's runners at 1.3 x 2.4 at the flange and the taper is very similar to the Stage VI RB one you sold me.

Mildly ported I don't see anything (short of a nitrous shot) that's going to out-torque the 2D from the basement to ~4500 on a 440, above it I would think it could easily keep up with a ported M1 or victor, and with more torque the vert is gonna pull harder so (as long as you hook the extra grunt to the ground) the 2d should work awesomely.

Thanks for the info on the 337. I'll have to see how things go w/ the M1 before I pick up any other intakes.

Update: I hid from everyone after putting the kids to bed last night and spent a couple of hours opening up the RB M1's runners to better match the CNC Victors.

Good News #1: I completed the heavy carving work for one bank's runners. There is still some surface finishing to do, but the major grinding work is done on that side.

Bad News #1: I found out the hard way that one roof could have used more weld at the corner of the outside wall, since I broke through in one spot and will need to get it welded again (or find somebody w/ some Belzona I can get a "sample" amount just to plug the hole).

Bad News #2: Jeez, it's been a long time since I did any serious head or intake grinding... my technique sucks! I was using some aggressive cutters because of the amount of material that needed to be removed and my own work would leave me pretty disappointed if I'd paid somebody else and gotten the same results. I may be able to clean up some of it, but it definitely reminded me of my part-time amateur porter status.

did you lube the cutters wd40 or atf

Brad...Did you take any pics?

I have a couple of different cutting lubricants I use, although IMO nothing does a great job w/ the open-flute aluminum-style cutters. I couldn't find my Mondello cutting fluid last night, though.

Pictures? Oh, I suppose I should take some. The biggest would probably come from doing side-by-side pics w/ the unmodified RB M1 I have, too. The one I'm working on now has had a LOT of mods from the plenum area on down over the years.

I don't have any pics,Brad...But Jimmy took quite a bit of material out of my M-1... No grinder smiley!!