Dual plane or single plane?

[roostwear]

The last project for my Advantage is a little induction work. I'm going to try adding a 2" carb spacer to the stock CJ manifold for now, but I'll be changing the intake in search of more r's. I have a Berk E with an A impeller, and my tach shows 4100 rpm. I have my doubts about that, but the pump is fresh. To the point..... for a jet, does a dual plane really make sense? I've heard 460s like to breath, and it would make sense to me that a single plane would help raise the powerband higher than a dual. Has anyone done a head-to-head (or even seat of the pants) comparison between the two?

[OMEGA_BUBBLE_JET]

I went from a edelbrock single plane to a dual plane performer RPM. I did not notice any gain in rpm on the top end but the RPM manifold had better all around driveability. I turn my engine 5300rpm with the RPM no problem. I think the RPM is best for ALL around performance. I also had a 650 holley on it last summer. Uping that to a 750 marine holley this year. Hope this helps.
Omega

[Ken F]

Had the same experience wth my 460.
After going from a single plane to a Weiand Stealth, bottom end & driveability greatly improved, top end stayed the same. Much more power out of the hole, and through mid-range.
Ken F

[roostwear]

Sounds like I wouldn't really be much better off than I am with the CJ. I have a Proform converted 4150 on the 68 I might bolt on the boat with the spacer. It's supposed to breath 830-850 cfm, and I KNOW it's a killer carb. The down side is the wife gets pissy when I start tearing apart the rides to try speed equipment on the boat............

[Squirtcha?]

I think the outcome of dual plane to single plane will depend alot on your other engine components.
If I run desktop dyno on my setup BBF 460 I show approximately 500 hp at 5500 rpm with my Weiand Stealth. By switching to the singleplane it jumps up to 520 hp. It doesn't help much if I can't spin my pump to the 5500 rpm though. Since I'm only turning 5300 rpm now, the increase wouldn't do me much good.
I was in pretty much the same boat (pun intended) as you a few years back. My basically stock Ford was turning 4400 rpm @ 62mph with an Edelbrock Torker singleplane and I made the switch to a Weiand Stealth and absolutely nothing changed. I can't even say I experienced any change in "driveability" as the others did. It ran the same rpm and the same speed as with the singleplane.
Probably the biggest benefit to you would be a pretty serious weight savings. That stock iron CJ probably weighs 60+ lbs.

[roostwear]

Squirtcha, here's my setup, and it probably wouldn't help alot changing intakes at this point. I'd probably get more out of it with D0VE or C9VE heads.
460 .040 over forged TRWs, w/ D3VE mildly ported heads. 8.5:1 comp with these heads. Comp Cams 230@.050, .530 lift 110 lc, CJ intake w/ 750 DP. I know I can pic up more with OTs, but this boat is more a cocktail cruiser than racer.
BTW, some lunatic on Banderlog came up with that name last year...... thanks!

[TopCat]

Originally posted by roostwear
Squirtcha, here's my setup, and it probably wouldn't help alot changing intakes at this point. I'd probably get more out of it with D0VE or C9VE heads.
460 .040 over forged TRWs, w/ D3VE mildly ported heads. 8.5:1 comp with these heads. Comp Cams 230@.050, .530 lift 110 lc, CJ intake w/ 750 DP. I know I can pic up more with OTs, but this boat is more a cocktail cruiser than racer.
BTW, some lunatic on Banderlog came up with that name last year...... thanks! Maybe others wont agree but with 8.5-1 it really isnt going to make much difference if you dont hav cobra jet valves porting those heads isnt going to buy you alot either Fords dont breath real well you need a bigger cam & more compression and try to find cjheads or at least hwy patrol heads it will still be skiable and alot quicker

[Blown 472]

Well there is a port mismatch between the intake and the heads. A small port stealth would work. If you do that, whatcha going to do with the iron intake??

[Jake W]

I was running a single Offey Tunnel Ram last year.And now I went to a Victor intake with a SB 2 inch spacer REX 1/4 in plate (for fule block and cable holder)and 1 inch NX nitrous spacer.so I guess I will have 3 and 1/4 in spacer under the carb.What do you guys think that will do?
Jake:D

[Squirtcha?]

Originally posted by roostwear
BTW, some lunatic on Banderlog came up with that name last year...... thanks!
Hey I resemble that lunatic thing. I ran your numbers on desktop dyno and it looks like the two biggest improvements would be to cut the impeller down to a point where you could run at 5000 rpm as that's where your peak horsepower is. It would get you a useable 50 hp over what you've got now at 4100 rpm. Headers would net you another 50 hp at that same 5000 rpm, but I understand wanting to keep it a cruiser.
With mine an additional 100 hp gets me about 7 mph with an increase of 350 rpm.
Then again, that motor will last you forever running at 4100 rpm and that's a really good thing.

[TopCat]

Originally posted by Jake W
I was running a single Offey Tunnel Ram last year.And now I went to a Victor intake with a SB 2 inch spacer REX 1/4 in plate (for fule block and cable holder)and 1 inch NX nitrous spacer.so I guess I will have 3 and 1/4 in spacer under the carb.What do you guys think that will do?
Jake:D I think you'll go faster

[roostwear]

Looks like there's only one thing to do...... N2O. perfect for 8.5:1 compression.

[TopCat]

Originally posted by roostwear
Looks like there's only one thing to do...... N2O. perfect for 8.5:1 compression. well that would be one way but with 8.5:1 a turbo would work wonders dont you think

[sleekster]

i run a tunnel ram with 2 450 holley's on my bbc and love it no hesitation when i stand on it and top end no problem, my theory is the 450's restrict air flow enough to provide velocity fo rthe intake charge at lower speeds, hence the drivability. it currently makes 475 hp 502 torque, the desktop dyno was way off, it estimated 600 hp.

[beached 1]

I'd say it depends on the manifold..
the Torker is a POS, IMO (acronyms goine wild)
comparing something like a Torker with the Wieand stealth isn't a fair comparison if you ask me....but I digress
Since most jets don't really start moving till after 3k rpms I chose to go with a single plane. I would have liked to have gone with the Victor Jr, but hood constraints and I would have to port my D0VE heads to a SCJ config, made me go with the Offy Port-O sonic (mid rise). I was using the Wieand (dual plane) stealth and saw pretty good results, but if you look at the Desk top Dyno, after 3k the single plane leaves the dual behind in HP..
Just my .02$

[Squirtcha?]

Originally posted by beached 1
I'd say it depends on the manifold..
the Torker is a POS, IMO (acronyms goine wild)
comparing something like a Torker with the Wieand stealth isn't a fair comparison if you ask me....but I digress
Since most jets don't really start moving till after 3k rpms I chose to go with a single plane. I would have liked to have gone with the Victor Jr, but hood constraints and I would have to port my D0VE heads to a SCJ config, made me go with the Offy Port-O sonic (mid rise). I was using the Wieand (dual plane) stealth and saw pretty good results, but if you look at the Desk top Dyno, after 3k the single plane leaves the dual behind in HP..
Just my .02$
While I agree that the Torker is a POS, it just goes ta show ya that it depends on the rest of your build. Sorta the point I was trying ta make. On my stock BBF I saw no difference between the POS Torker and probably the best dual plane there is for a BBF, the Weiand Stealth. One thing's for sure, there is a pretty big differential between the two (dualplane/singleplane notwithstanding) and I got no gains or losses. It was exactly the same with both intakes. Guaranteed if I put that old Torker on my motor (after the rebuild) you would definitely feel a difference between the two now.
Also agree that the only time my motor runs at less than 3000 rpm is when idling in a nowake, or pulling my kids skiing, neither of which really matter in the big picture.
Wrestled real hard with the Victor jr. and Weiand Stealth thing. I was buying new heads anyway and had trouble figuring out which way ta go. As it turns out, it was all for naught as I'm in the process of changing over to a TR with 660's anyway.

[beached 1]

Originally posted by Squirtcha?
As it turns out, it was all for naught as I'm in the process of changing over to a TR with 660's anyway.
A real single plane, Nice! Please post your gains when you do. It sounds like we have similar engine builds (Mine w/o NOS though) and I like to dream about running a TR as well. The way BBF int ports are spaced apart, it seems like they should olny be run with duals..
I was running a Speed Demon 750 dp with a Wieand Stealth last summer and was pretty happy with it. For this summer I'm switching to the Offy mentioned above and a HP950 from TPC Racing (Hotcrusader). I know it's not a fair compairison without running the old carb. so, I was thinking of running the Demon around the lake just to see what the diff the Offy would make. If I do, Ill post the results.

[beached 1]

Originally posted by beached 1
A real single plane, Nice! Please post your gains when you do. It sounds like we have similar engine builds (Mine w/o NOS though) and I like to dream about running a TR as well. The way BBF int ports are spaced apart, it seems like they should olny be run with duals..
I was running a Speed Demon 750 dp with a Wieand Stealth last summer and was pretty happy with it. For this summer I'm switching to the Offy mentioned above and a HP950 from TPC Racing (Hotcrusader). I know it's not a fair compairison without running the old carb. so, I was thinking of running the Demon around the lake once just to see what the diff the Offy would make. If I do, Ill post the results.

[Squirtcha?]

Please post your gains when you do.
Sure will Beached. I know that DTD is far from accurate in most cases, but it shows a gain of approx. 50 hp. I figure that will equate to 3 mph or so. We'll see.
I'd be real interested to see the results if you run the old carb on the new intake.
I'm running a Holley 850 dp on my Weiand. I've been real happy with it and probably never woulda changed it, if I hadn't gotten such a good deal on the TR and carbs. Just couldn't resist though. I'm keeping the old setup. Not sure what the two carb setup is going to do to my fuel consumption yet, and it's going to be an expensive summer as it is. If it's too bad, I'll switch it back for the cost of some intake gaskets.

[Jet City]

I was using the Wieand (dual plane) stealth and saw pretty good results, but if you look at the Desk top Dyno, after 3k the single plane leaves the dual behind in HP..
Just my .02$ [/B][/QUOTE]
There are several areas of Desktop Dyno that are really lacking, as you stated the Stealth would probably crush the old Torker in reality (I think it outguns the Torker 2 as well), these modern dual planes are a far cry from their predessors, they pull hard to 6500 rpm and are usually in the hunt with the best single planes up to that point, I would think this would be favorable for the typical jetboat that cannot acheive more than about 5000 rpm's. I have the Stealth and like very well (with a 800 DP), if for no other reason than never again having to pull that boat anchor CJ manifold off again (its under the bench were it belongs) its worth the $165. I paid for it. I think you'd be real happy with the Stealth, Edelbrock RPM or the Victor 4150 (they never made a Victor JR for BBF). There is a guy on the BBF forum who uses a Stealth with a 4500 adaptor and a 1050 Dominator that runs low 10's in a 3200lb car, which indicates he's making a little over 600 hp (ported D3 heads too!), I thought that was a good testamony to the Stealth's potential.
Dan,
I hope you give a full report once you try your new Tunnelram, I just bought some 660's myself, should be really fun to monkey with!

[roostwear]

I ran the 8012 Stealth on my Tahiti, and liked it. I may pick up a little putting one on this motor, but my goal is to change to D0VE heads. Not for the breathing, but to pick up a point in compression. With the heads and intake, I would probably hit the wall with the logs, so going any further would be a waste. I just have to keep telling myself it's just an old open bow with an E pump......

[cal perf 19]

I went from the weiand single tunnel ram to the stealth and there was quite a difference between the the two with the TR I could never get the plugs to color correctly. with the stealth I picked up a whole bunch of bottom/midrange but didn't notice any top end change. If you go to the single plane you will have to cut the impeller for sure. If your interested I have the motorsport single plane for sale. Check Real Jet boats.com under jetters parts for the listing.
Hope this helps BK