intake plenum divider
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From: wilson,nc,usa
intake plenum divider
I think I have asked thiis before but Im asking again. I have a 454 LS7 crate in my 66. It has a 65 396-425 hp intake on it . The divider has been milled out all the way to the bottom. If I have the divider welded back in will I be able to "feel" a bottom end torqe improvment, or would it be a waste of time.
These motors are strong above 3500 RPM....Im just looking for a little more on the bottom.
JEff
These motors are strong above 3500 RPM....Im just looking for a little more on the bottom.
JEff
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From: Taylor Michigan
Re: intake plenum divider (six-T-six)
Hello, I`m not Jeff, but I run a true LS7 crate engine in one of my other toys, a 68 SS 396 Camaro. I am using a stock L88 intake. {open Plenum} 850 double pump carb. Large Hooker comp headers into Walker race 3 in. bullet mufflers, 4.56 gear, 1975 HEI ignition, manual shift turbo 400 and 3500 stall converter and trans cooler. Stock Camaro radiator, starter, fuel, steering, oil and water pumps. With 9 in. slicks it procuced on a basically stock LS7, 11.42 at 119 mph and NO cage right out of the box. They told me to go home or slow it down to 12.0. :lol: I recently placed some Dart Aluminum heads on it to cure those heavy iron heads and take some weight off. Approximately 70 lbs. If it was in a Vette, it should run quicker than in the Camaro. Nothing trick about the setup, it just runs great using 100 avaition gas. 7 miles to the gallon however. :cheers: :lol:
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St. Jude Donor '03 & '05
Re: intake plenum divider (Ironcross)
Awesome! :cool: I am running a crate LS-7 with a single plane Torker with a 850 dbl pumper. Headman headers to side pipes with MSD distributor and ignition, 4.11 gears. I think I'm going to go to bigger headers and better sidepipes next.
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From: wilson,nc,usa
Re: intake plenum divider (six-T-six)
Im running stock LS7 with a 850 DP holley,355 gears,headmons into fact sidepipes. Im also running repo bias ply redline tires that do nothing for traction. Are you guys running the LS7 cam? How does your combo run six-t-six?
Jeff
Jeff
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St. Jude Donor '03 & '05
Re: intake plenum divider (jeff batchelor)
It's kind of subjective I guess, but it ran great to me. Lumpier idle and less torque down low than my hydraulic cam 427 but the 4.11 gears kept it higher in the RPM range. I am using the LS7 cam. This combo was my daily driver for three years. :D I used 94 octane pump gas, retarded the timing and lashed it looser and it was fine. Only thing that I've had to do was replace some blown head gaskets. Like you, I had a traction problem with 225/75-R15 tires. :D
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From: Southwest MI
Re: intake plenum divider (jeff batchelor)
i agree, the factory L-72 divider will give you more below 3500. i did some testing on my own, starting with the L-72 intake, then a notched plenum L-72 (both with a 850 DP), then the 2nd design L-88 intake (with a 855 stagger jetted carb with the air flow tabs, no choke). i ended up going with the L-88, it equals the L-72 at ~4000 with a 468, but makes significantly more power 4500-7000. i haven't learned to post pics here but if you guys want to see my intakes i'll email them to you (i mailed them to you Jeff). actually, i think the notched plenum divider is really a good compromise (the stock L-72 intake is a little restrictive for 454+" in the upper RPM ranges)..... but i'm setting up for max perf 4500-7000 so the L-88 intake is just what the Dr. ordered, for me that is :-)
PS: and really, killing a little power down low will help HP BB's launch on C-2 size tires. i've learned some of the guys running in those "stock muscle car" classes, with f70's, cut the dividers out just for that reason..... pulling harder up top is an added bonus.
[Modified by 66427-450, 6:36 PM 4/10/2004]
PS: and really, killing a little power down low will help HP BB's launch on C-2 size tires. i've learned some of the guys running in those "stock muscle car" classes, with f70's, cut the dividers out just for that reason..... pulling harder up top is an added bonus.
[Modified by 66427-450, 6:36 PM 4/10/2004]
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From: wilson,nc,usa
Re: intake plenum divider (66427-450)
Thanks for the info and pics 66427. Yea ive been reading in Hot Rod about the guys cutting the divider out of there intakes in the muscle car drags. Im just looking for a little more throttle responce for street driving since I dont drag race my car.
Jeff
Jeff
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From: Taylor Michigan
Re: intake plenum divider (66427-450)
One significant fact about the L72 and L88 intakes are that they are both dual plane manifolds. No bottom end is sacrificed with either one. It`s just as you suggested [66427-450] that the L88 works better at the higher HP and RPMs with the open plenum. It is very tough for a aftermarket intake to be any better for most all around usage. :thumbs:
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From: Clayton NC
Re: intake plenum divider (Ironcross)
"Im also running repo bias ply redline tires that do nothing for traction. "
That's the understatement of the year... :lol: :lol: Jeff can't wait to see if I have a traction problem... So when we going to pull the motor man and put some more go fast goodies in... I'd hate to see my lil mouse run away from that Rat.... :eek: :D :cool: Dave..
That's the understatement of the year... :lol: :lol: Jeff can't wait to see if I have a traction problem... So when we going to pull the motor man and put some more go fast goodies in... I'd hate to see my lil mouse run away from that Rat.... :eek: :D :cool: Dave..
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From: Southwest MI
Re: intake plenum divider (jeff batchelor)
........ Im just looking for a little more throttle responce for street driving since I dont drag race my car.
Jeff
Jeff
:)
