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Discussion Starter · #1 ·
I am converting over to F.I. this year and going to run a Mean street EFI. My question is, I have a Victor JR right now, would I benefit any from going to a dual plane, such as an Edelbrock RPM Air Gap or non Air Gap? I am changing to 3.42's which should get my RPM's down below 2000 on the highway, and to me it would seem it would work better with the dual plane. The trans is a 700R4 with a 3200 rpm lockup converter. Thanks!
 

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might have issues with dual plane

i have Victor jr-o efi manifold in my mpfi BBC and runs perfect and i do most of my driving in 2000-3000rmp area
 

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Discussion Starter · #3 ·
Not sure if that has to do with it being an LS engine or not, but most of these I have seen are running dual plane intakes. The Victor Jr is rated at 3500-8000 RPM, so I was thinking that a dual plane might work better? But if the single plane will work just fine, I will stick with it. I have seen the Performer RPM air gap mainfolds at swap meets for around 150 quite a few times.
 

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Single plane, less curves = less fuel fallout.

With no need to worry about carb signal, the dual plane loses its advantage with injection.
 

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I'd use what you have solely because you already have it...but my Weiand Stealth dual plane works great from idle to 6500 and anywhere in between.

Worked great with the Fitech and works great with the Holley Sniper now...They're both annular discharge, like most carbs, so not sure why some people insist they don't work on a small block or big block, like that LS video supposedly shows.
 

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Discussion Starter · #6 ·
this is great news! The extra money that I save from the intake will buy me my tank and fuel pump. That is if I bought the intake new. Going to run a Tanks Inc 18 gal tank and the EFI Fuel pump. Hoping to go on the Hot Rod Power Tour for a day or two this year! Thanks everyone for your help!

Anyone know what kind of mileage I would gain over my annular booster 850 Holley DP? Getting right at 8-9 mpg running 65-70 mph and at 2700 rpm or so. That is on a long trip. I have a 3.90 now, but I am converting to 3.42's with the lock up 700R4 converter, I should have my RPMs right at 2000. Should make for a much better driving car.
 

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I would definitely bet on better driveability, but even though mine seems to be better on gas, judging by how often I add it, I have 2 things working against me...

1. My odometer doesn't work.
2. The car runs so good, it's EXTREMELY hard to not do "acceleration testing" multiple times during each drive... :wink2:

I went from a Quick Fuel SS-830, to the Fitech GO-Efi4, to the Holley Sniper, so have had quite a few different "feels" to my setup...

Doubtful I'll ever buy another carburetor. :thumbsup:
 

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this is great news! The extra money that I save from the intake will buy me my tank and fuel pump. That is if I bought the intake new. Going to run a Tanks Inc 18 gal tank and the EFI Fuel pump. Hoping to go on the Hot Rod Power Tour for a day or two this year! Thanks everyone for your help!

Anyone know what kind of mileage I would gain over my annular booster 850 Holley DP? Getting right at 8-9 mpg running 65-70 mph and at 2700 rpm or so. That is on a long trip. I have a 3.90 now, but I am converting to 3.42's with the lock up 700R4 converter, I should have my RPMs right at 2000. Should make for a much better driving car.
Don't expect LS numbers. You will get better mileage though. When you are getting 8-9 MPG, a 20% increase in mileage is only 1.6 to 1.8 MPG. You should do better than that though with the gearing change. Maybe you can push it to a 50% increase over 8 MPG and get 12 MPG. :wink2:

In my case, the mileage got better, but I had to input different AFR numbers to make that happen. Drive time also makes a difference. My car really runs well now, but it took at least 1500 miles and a lot of different driving conditions. It's really just starting to show a noticeable improvement in gas mileage after 3 months. Still I'm talking small numbers, like 2-3 MPG better driving the speed limit.
 

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I am converting over to F.I. this year and going to run a Mean street EFI. My question is, I have a Victor JR right now, would I benefit any from going to a dual plane, such as an Edelbrock RPM Air Gap or non Air Gap? I am changing to 3.42's which should get my RPM's down below 2000 on the highway, and to me it would seem it would work better with the dual plane. The trans is a 700R4 with a 3200 rpm lockup converter. Thanks!
I have a setup a little similar to yours (496 cu.in. Edelbrock Victor Jr. 454R intake manifold, 700R4 trans. with lockup and 3:73 gears) and I also plan to convert it to fuel injection. I intend to keep the same intake manifold (single plane) which I think is best recommended for F.I. The only change to the car other than swapping the carburetor for the throttle body will be to add a fuel return line and an in-tank pump….but if you ask me, I'd say to keep the intake manifold you already have, you'll be fine with it. :yes:

Good luck,

Claude. ;)
 

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Discussion Starter · #10 ·
well my thinking is that going to an EFI should be a bit more efficient, but getting my rpms down 800 rpm or so, would give me a bit more efficiency hopefully as well.
 
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well my thinking is that going to an EFI should be a bit more efficient, but getting my rpms down 800 rpm or so, would give me a bit more efficiency hopefully as well.
Just make sure your cam and timing advance will like being locked up at 2k.
My sons Malibu had a 200r4 with 3.42's and a 28" tire.
You had to be doing at least 65 to lock it up.

Now I'm on the other side with 4.30's.
I have my controller set to lock at 55 and I'm somewhere around 2400 which may not sound good to you but is a huge difference to me.
According to my controller's TPS, my son said I was at 2% throttle at 55.
It picks right up with very little throttle input locked and will unlock at anything more then 35% throttle.
 

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Just make sure your cam and timing advance will like being locked up at 2k.
My sons Malibu had a 200r4 with 3.42's and a 28" tire.
You had to be doing at least 65 to lock it up.

Now I'm on the other side with 4.30's.
I have my controller set to lock at 55 and I'm somewhere around 2400 which may not sound good to you but is a huge difference to me.
According to my controller's TPS, my son said I was at 2% throttle at 55.
It picks right up with very little throttle input locked and will unlock at anything more then 35% throttle.
What controller are you using?

My 700R4 lockup/unlock is on a manual toggle, because my TCI vacuum switch setup was pooh. I may fix that this summer with a better vacuum switch, but I digress.

I can put my trans into lockup at 50 if I want to and it'll putt right along with low throttle input. RPMs are around 1600 at 50 in lockup. Large throttle input response at low RPMs is rough on the motor and trans unless it is unlocked, so I don't do it. I generally don't use lockup unless going 65 and there is free flowing traffic in front of me. Big throttle input at 65 and 2000 RPM is not that great. My motor with the FiTech would rather be at around 2600 RPM in lockup before I give it larger throttle input, but I'm running around 77 MPH at that point, and the cops don't appreciate it.

Oddly, my motor made better power cruising at low RPMs in lockup with the carburetor, but I was running a 670cfm single pumper vacuum secondary Holley. The throttle body is 1000cfm, and all four throttle blades open at once. Lot o air to deal with if the motor isn't wound up.

Anyway, that's my long winded way of saying, yeah the motor might not respond well at low RPM in lockup.
 

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Discussion Starter · #13 ·
Maybe i will just add the FItech and see what happens. My cruise rpms are 2600-2800 with the 3.90's. I have no controller. My lockup is all cable driven.
 

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Maybe i will just add the FItech and see what happens. My cruise rpms are 2600-2800 with the 3.90's. I have no controller. My lockup is all cable driven.
I did not know that was possible. Live and learn. I thought the torque converter lockup in a 700R4 had to be engaged electrically. Mine does.

If your lockup works and unlocks quick when you press on the go pedal, it'll work with the higher rear end gears. Mine won't unlock unless I toggle it off, so I've experienced the worst case lugging scenario when cruising slow and forgetting to unlock it when I want to go. If I unlock it, it goes like it should. Although as I said not quite a strong as the smaller vacuum secondaries carburetor.
 

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Discussion Starter · #15 ·
I did not know that was possible. Live and learn. I thought the torque converter lockup in a 700R4 had to be engaged electrically. Mine does.

If your lockup works and unlocks quick when you press on the go pedal, it'll work with the higher rear end gears. Mine won't unlock unless I toggle it off, so I've experienced the worst case lugging scenario when cruising slow and forgetting to unlock it when I want to go. If I unlock it, it goes like it should. Although as I said not quite a strong as the smaller vacuum secondaries carburetor.
Yeah. Mine has the conversion kit in it, so everything is controlled by the throttle valve cable. It does disengage immediately, so maybe a 3.42 with my setup won't hurt anything.
 

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Yeah. Mine has the conversion kit in it, so everything is controlled by the throttle valve cable. It does disengage immediately, so maybe a 3.42 with my setup won't hurt anything.
It'll work then.

Good luck with the FiTech throttle body. It's a good product. Only real downside is you might have to do some minor tuning and the connection to the handheld is fragile and goofy.
 

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My controller is a compushift 1.
Great pruduct. Even if its 13yrs old! I still get support from the engineer who designed it!
I just mentioned it because of possible detonation while in lock up. That's all.
That controller sounds good. I checked into it, but it looks like I might not be able to use one. I have a constant pressure valve body, and would need to install a TPS. I don't see how the TV cable could be installed with their TPS sensor. Looks like it would interfere, and generally be in the way. I might be able to tap into the TPS on the FiTech. Something to think about.

Fortunately my motor won't detonate lugged on 110 degree days with Arco regular in it. low compression, big combustion chambers, aluminum heads. ;)
 
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