416" on the dyno

[rmchrgr]

The intake is another issue with most not flowing what the head flows , theyre corks...

The previous RHS-headed version of my motor had a gasket-matched Holley Strip Dominator. In my estimation the issue with that particular intake is volume as the runners and plenum are both smaller than optimal for displacements over 400 c.i. They were designed in the late '70s before stroked small blocks became popular. Gasket matching it probably didn't do much of anything save for bell mouthing the port entry about 2" into the runner. So yeah, I'd say that it was probably a cork. A regular Edelbrock Victor 340 would have been a much better choice even without doing much of anything to it.

That first version of the engine made peak power at 6,000rpm and it fell off a cliff right after. What it did well though was make a ton of torque. The curve was flat from 4,000-5,500. It didn't go below 450ft lbs. throughout that range which is big-block territory. The cam in it was not small by any stretch - 251/259 @ .050" so that wasn't holding it back.

About 12 years ago, I had a Mopar .528" cam in my old W2 340 engine that would rev to 7,200+. That engine had heavy TRW pistons, way less cam duration and lift and the old W2 heads flowed less air but that combo went 1,200 rpm higher than the 416". That was a fun engine but it made zero torque and needed 4.30 gears at a minimum.

I believe that's just an inherent property of 4" crank combos whether they have enough head flow or not because they are square or under square. That architecture just seems to favor low rpm torque over high-rpm peak power. The current 600+hp version of my 416" has both the head flow and a decent size cam but it still makes big torque over 5,000 rpm and the revs. only top out around 6,500. I agree that whatever the displacement, getting a 4" crank combo to rev over 7,000rpm is going to make it a race-only piece. Right now I'd say mine is on the edge of street driving.

3.79" stroke engines are great in their own way but they probably don't make the same kind of torque a 4" stroke engine would. The majority of people on here like me are building street/strip type engines and torque is king on the street so you can see why the 4" stroke caught on. Getting easy big block power and torque out of small block is just a no-brainer.

I have an old Mopar 3.79" crank (340 journal) collecting dust that I'd like to use some day. In one of my other 340 blocks it would make 394" which is probably about right for the RHS heads. I'd rev the piss out of it!

 

[MOPAROFFICIAL]

The previous RHS-headed version of my motor had a gasket-matched Holley Strip Dominator. In my estimation the issue with that particular intake is volume as the runners and plenum are both smaller than optimal for displacements over 400 c.i. They were designed in the late '70s before stroked small blocks became popular. Gasket matching it probably didn't do much of anything save for bell mouthing the port entry about 2" into the runner. So yeah, I'd say that it was probably a cork. A regular Edelbrock Victor 340 would have been a much better choice even without doing much of anything to it.

That first version of the engine made peak power at 6,000rpm and it fell off a cliff right after. What it did well though was make a ton of torque. The curve was flat from 4,000-5,500. It didn't go below 450ft lbs. throughout that range which is big-block territory. The cam in it was not small by any stretch - 251/259 @ .050" so that wasn't holding it back.

About 12 years ago, I had a Mopar .528" cam in my old W2 340 engine that would rev to 7,200+. That engine had heavy TRW pistons, way less cam duration and lift and the old W2 heads flowed less air but that combo went 1,200 rpm higher than the 416". That was a fun engine but it made zero torque and needed 4.30 gears at a minimum.

I believe that's just an inherent property of 4" crank combos whether they have enough head flow or not because they are square or under square. That architecture just seems to favor low rpm torque over high-rpm peak power. The current 600+hp version of my 416" has both the head flow and a decent size cam but it still makes big torque over 5,000 rpm and the revs. only top out around 6,500. I agree that whatever the displacement, getting a 4" crank combo to rev over 7,000rpm is going to make it a race-only piece. Right now I'd say mine is on the edge of street driving.

3.79" stroke engines are great in their own way but they probably don't make the same kind of torque a 4" stroke engine would. The majority of people on here like me are building street/strip type engines and torque is king on the street so you can see why the 4" stroke caught on. Getting easy big block power and torque out of small block is just a no-brainer.

I have an old Mopar 3.79" crank (340 journal) collecting dust that I'd like to use some day. In one of my other 340 blocks it would make 394" which is probably about right for the RHS heads. I'd rev the piss out of it!

The holley strip dominator is in the 240 cfm territory, so there's your answer.

 

[polyjohn]

Wowsers, that is the best 340-smallblock video I have ever seen.
Gonna be doing my 416 next year so I'm hoping for 500hp/500lbsft.

That's NINE seconds all day long in my book.
We ran 10.40 with an all iron 440 and 550hp.

Best thread on this site in many a moon.
BRILLIANT STUFF...

 

[rmchrgr]

Thank you! I agree that getting power like this out of a standard port head and a very basic overall combo is a pretty big accomplishment. It certainly boosts my confidence in whatever meager engine building skills I possess. Now I just have to do it again to prove it wasn't a fluke!

Pretty sure this engine will get the car in the 9s at some point but it won't happen right away. Frankly, I've never been that quick so it's not like I'm going to jump in the car and run that number. A lot that has to happen in between the dyno and running a certain ET. I am happy it has the potential on paper but realistically it will be a while before I can claim it's a 9 second deal. Like pittsburghracer used to drill into everyone's head "we don't race dynos!" Too many variables to factor in besides the HP numbers at the crank.

I'm aware that some of things beyond the engine that are in the car now may be less than optimal but I'm not going to change anything else before I get some seat time. The current version of the engine is the culmination of the 2nd full re-do of the car from 10 years ago when it was going 12.0s @ 110mph. Everything in the car is new so it's going to take some time to sort it all out.

This Wallace Racing calculator says the car will go in the 9s which gives me something to shoot for. I've seen several people say this particular calculator is pretty accurate. For what it's worth, it spit out the exact rpm at the stripe that I would be aiming for, 6,600. If it is right, 135 mph is hauling the mail but a 1.38 60ft time is not likely going to happen without some serious testing and tuning.

 

[B3422w5]

Thank you! I agree that getting power like this out of a standard port head and a very basic overall combo is a pretty big accomplishment. It certainly boosts my confidence in whatever meager engine building skills I possess. Now I just have to do it again to prove it wasn't a fluke!

Pretty sure this engine will get the car in the 9s at some point but it won't happen right away. Frankly, I've never been that quick so it's not like I'm going to jump in the car and run that number. A lot that has to happen in between the dyno and running a certain ET. I am happy it has the potential on paper but realistically it will be a while before I can claim it's a 9 second deal. Like pittsburghracer used to drill into everyone's head "we don't race dynos!" Too many variables to factor in besides the HP numbers at the crank.

I'm aware that some of things beyond the engine that are in the car now may be less than optimal but I'm not going to change anything else before I get some seat time. The current version of the engine is the culmination of the 2nd full re-do of the car from 10 years ago when it was going 12.0s @ 110mph. Everything in the car is new so it's going to take some time to sort it all out.

This Wallace Racing calculator says the car will go in the 9s which gives me something to shoot for. I've seen several people say this particular calculator is pretty accurate. For what it's worth, it spit out the exact rpm at the stripe that I would be aiming for, 6,600. If it is right, 135 mph is hauling the mail but a 1.38 60ft time is not likely going to happen without some serious testing and tuning.
View attachment 1716474821

Way better info than that calculator are that there are a number of us out there already doing what your in the middle of doing, so it isn’t much guesswork to know what the car should run, with even middling chassis, convertor setups.

 

[HuntedDuckV351]

What CC were your heads? I think mine are 72 CC from Rod but im going with dome pistons.

 

[rmchrgr]

Way better info than that calculator are that there are a number of us out there already doing what your in the middle of doing, so it isn’t much guesswork to know what the car should run, with even middling chassis, convertor setups.

OK, I'll take your word for it!

Apologies if I posted all this already but the chassis is as follows; QA1 front end, (saved 18lbs. over the stock stuff) FMVB 904 with 6 front and 5 rear clutches (no low gear set though, probably don't need it), old-school square tube frame connectors, 6 point cro-mo roll bar, (for now) Caltracs with their adjustable shocks, 28" drag radial, 4.10 gear. As I mentioned to you converter is a 9 1/2" 4,500 which after calling them direct Dynamic says should be OK.

Figure I'd start the launch process at 1,500 and go from there. My last set of brakes wouldn't hold at the car over 1,200 and the 60fts were usually in the 1.7s which are commensurate with the 12.0 ET. Like I said, getting this car to go 1.4 in the 60 will be a fairly monumental achievement. Once I get some time slips I'll probably be looking into getting some decent shocks.

Not totally sure on the weight yet but hoping/believe it is in fact under 3,000 without me (195). No heater, radio, back seat, one Kirkey aluminum seat, fiberglass hood, aluminum rad, aluminum bumper brackets (by JB Mopars in MI.), lighter Wilwood brakes in front, yada yada. If/when I have to go to a cage I'll start looking into ways to compensate for the extra weight. Has a full 3" exhaiust too which is heavy. I decided against turn downs and the full tubing keeps some weight in the back.

Yes, those are real Fenton Gyros. I need to swap the wheel studs for shorter ones, don't need 2" sticking out of the lug nuts. Also have a set of slightly taller M/T radial front runners that I need to put on.

 

[rmchrgr]

What CC were your heads? I think mine are 72 CC from Rod but im going with dome pistons.

That's the one thing I didn't measure but I'm thinking they are more like 68cc? The pistons I have are flat top with a -5.6cc dish and are true zero deck with a .0039" head gasket. Rod asked me what the cylinder pressure is but we didn't check that on the dyno. I'll do it when it's in the car but I'm betting it's 200 psi. or more.

 

[B3422w5]

That's the one thing I didn't measure but I'm thinking they are more like 68cc? The pistons I have are flat top with a -5.6cc dish and are true zero deck with a .0039" head gasket. Rod asked me what the cylinder pressure is but we didn't check that on the dyno. I'll do it when it's in the car but I'm betting it's 200 psi. or more.

I had mine cut to 61cc but not sure how they came, that was enough to raise it to 12.3 ish compression. Just had Rod have them skinned before I got them. I want the extra squeeze and like running 110. I want to say they are around 68cc, but won’t swear to that.
I have zero deck flat tops ( icons) with the dinosaur ring packs.
My cylinder pressure is currently 180-185, I should have put new rings in it when I had it apart, but didn’t.

 

[rmchrgr]

I figured 68cc chamber which puts my combination of parts at 11.3:1. If they are in fact at 72cc then I'm only at 10.8:1 compression which I doubt would have been enough to make that same power. Maybe 200psi is a little optimistic if you have over 12:1 and 185 psi.

No fancy metric ring pack for me either, just standard Total Seal file fit. I don't remember the gaps but they are 'within spec'.

 

[HuntedDuckV351]

I figured 68cc chamber which puts my combination of parts at 11.3:1. If they are in fact at 72cc then I'm only at 10.8:1 compression which I doubt would have been enough to make that same power. Maybe 200psi is a little optimistic if you have over 12:1 and 185 psi.

No fancy metric ring pack for me either, just standard Total Seal file fit. I don't remember the gaps but they are 'within spec'.

Still made really good power. I asked Rod for a bigger CC head because of the dome pistons. Wanted 12.5ish compression. When I stated the project I had different idea and was going to shoot for 13.5-14.0 compression but with the bloomer heads i figured i didn't need all that. Mine are wiesco domestic with .043 ring pack and gas ported with .927 pins.

 

[B3422w5]

I figured 68cc chamber which puts my combination of parts at 11.3:1. If they are in fact at 72cc then I'm only at 10.8:1 compression which I doubt would have been enough to make that same power. Maybe 200psi is a little optimistic if you have over 12:1 and 185 psi.

No fancy metric ring pack for me either, just standard Total Seal file fit. I don't remember the gaps but they are 'within spec'.

I think my 185 is a byproduct of reusing rings I shouldn’t have. Now have some blowby I didn’t have before, that I hope a pan evac setup will help with.

 

[rmchrgr]

A vacuum pump will be better and will even make power but they are way more expensive.

 

[HuntedDuckV351]

What intake gasket did you use?

 

[rmchrgr]

Superformance. No one makes a gasket with this size opening so you have to cut them or they overhang into the ports by a bunch. This was not an easy job, very tedious and time consuming. Make sure you buy an extra set of gaskets, I trashed one. I remember Don/B3422W5 telling me he didn't get involved with this type of thing on his motor and I can see why. I don't recommend it either but I couldn't live with the overhang.

Here's the final fit looking through the intake plenum. I like to think my efforts had a positive effect on performance but I have no way to quantify that.

 

[tjpatte]

Wow, not much room left on the top of that one port, very nice work Sir! I would be unbelievably happy with the results of that build.

 

[B3422w5]

I just used the 1213 Felpro intake gaskets. There is indeed some overhang, but I talked to several people about it and they all said it wasn’t at all a big deal.
That said, the ports are friggin tall

 

[HuntedDuckV351]

Yes those are some tall ports. I will get a couple sets of those gaskets. I have both a new super victor and a victor 340. The Victor 340 has been ported by Pittsburgh racer a few years ago. Thanks for the info. What did you paint the inside of your motor with?

 

[rmchrgr]

Yep! The ports on the BPEs are 2.5” tall x almost 1.2x” wide. I talked to Rod about it specifically and he said oh yeah, you definitely gotta cut the gaskets. You can argue for or against it but it wasn’t a question for me. I probably wouldn’t have bothered with the intake so much if I didn’t care about the overhang.

Fel Pro 1213 and most other intake gaskets are 2.27” x 1.16”. There might be some out there that are 2.3” tall but I wouldn’t bother finding those because you’d still have to cut them and it’s easier to work with more material.

The lifter valley is painted with GE Glyptal. It’s normally used to seal the insides of larger electric motors. I’ve used it on a few engines, I like it. It’s supposed to help oil drainback but again, not sure how you’d quantify that. If you want to go the extra mile you can also coat the inside of the timing chain area and the underside of the valley where the main webbing is.

Some people won’t use it because there are stories out there of it peeling off but that would be because it was put on a dirty or contaminated surface. Success with Glyptal is all in the prep. Clean, clean, clean and then clean again.

 

[rmchrgr]

I know Don uses a Victor and he seems to do OK with it but after destroying mine trying to port match it to the heads it became obvious to me that you “need” the Super Victor. The SV has more material on top and the angle of the runners matches up much better. Put them both on and you will see for yourself.

That was another thing Rod confirmed to me directly. He even goes “oh yeah, I thought you knew you needed a Super Victor”! I was like uhhhh no, but thanks for telling me after the fact Bud!

BTW, the newer Super Victor has the port injection bosses cast in and though I didn’t have one to mock up I would bet that those will need to be ground down a bunch if you actually want to install valve covers. My SV is the older one without those and it still required a bunch of grinding. That’s both on the intake side and the valve cover rail. Creating clearance for valve covers is typical with any 'high rise' intake though.

Note the boss at the base of the runner is ground away and also how much you have to take off the valve cover lips to make them fit. Some points required grinding beyond the lip into the rail surface. You can use valve cover spacers for this issue but I chose not to.

Sometimes you gotta do stupid crap like this since no one including Mopar Performance has cared about making life easy for small block Mopar guys since forever.

 

[rmchrgr]

I will admit that I am proud of this intake. I started a thread about it last year, you can read about all my trials and tribulations with it if you're so inclined. Member @Plymouth 65 sold it to me. (thanks Ken). I believe it was originally gasket matched by Hughes some time ago which per Don could very well mean that Vic Bloomer did it when he worked there. I felt bad about grinding on it, it was very nicely done. Red paint is obviously gone.

 

[HuntedDuckV351]

Yeah my super victor has the bosses on it. I planed on getting the spacers for the valve covers. I will try both and see. I would like mine to run in the middle 6.30s in the 1/8th. Easier to slow down to 6.40 so I don't have to get my license and chassis certified.

 

[HuntedDuckV351]

Did you have to grind any of the pushrod tunnel? I bought 1 each 1.5 and 1.6 hughes rockers to see how they fit plus I run 1.5 harland sharp and my kid has the 1.5 pro comps.

 

[B3422w5]

Yeah my super victor has the bosses on it. I planed on getting the spacers for the valve covers. I will try both and see. I would like mine to run in the middle 6.30s in the 1/8th. Easier to slow down to 6.40 so I don't have to get my license and chassis certified.

You’re not going to have absolutely any problems running that kind of number at all. Aren’t you around 3000 pounds sitting at the line!

 

[B3422w5]

Probably goes against the grain a little bit, but personally, I don’t think a well done Victor is giving up much power to speak of compared to a super Victor, on these types of motors. I don’t think they have been tested back to back at a track that I know of
My Victor is very nicely ported, and unless the super Victor is done to the same level of care, they can actually be duds.
That plenum is friggin huge on the super. I would love do a direct swap and look at both time slips, I don’t suspect there would be enough difference to raise an eyebrow.
This is my intake after it was done