camarof41_383

iTrader: (7)

I have a super victor intake on my carbed 408LS and the outer cylinders 1,7, 2, 8, always run much richer than the inner ones 3, 5, 4, 6. If I idle for awhile the spark plugs in the outer cylinders tend to start to turn black and the inner ones still look good. If I drive the car and make a high rpm blast then shut the car off shortly after the spark plugs tend to look more even but the inner cylinders always look leaner. I've had other single plane intakes that were very similar on SBC's and they didn't have such a disparity between cylinders. Just wondering if I've got a problem or if its normal for this intake?

james41

If you look at the super victor or even the victor Jr. for the LS motors, their runner on the outer cylinders are way longer than the inside cylinders.I was always told that runner length can have an effect on fuel/air suspension as well as A/F ratio.On the first gen chevy small blocks the runners are not quite so different in length.Just for your info a few of my friends locally had problems with Ford single plane intakes years ago that were very similar to what you describe.I even got a 750 DP holley carb that was barely used for a really cheap set of rusty Blackjack headers that I bought at a yard sale for 5 bucks for it.The guy had fuel distribution problems similar to yours on his ford and after a jet change and minor tuning it ran great for me for years on my sbchevy.

xpndbl3

iTrader: (23)

can't read plugs unless you pop in a fresh set, make a pull, shut off and read them, after that they're "driver" plugs only, not good to read anymore

james41

I agree about the right way to read a set of plugs,But you can't help but wonder if the discrepancy in runner length is enough to cause fuel distribution issues.I don't mean to knock edelbrock manifolds as the previous post I wrote I didn't mention that I was running a 1st gen chevy sb victor junior.Also it had been modified per specs reccomended by Joe Sherman.Most of you guys forty or so may have heard of him as in the late 80's-early 90's he was ducking traditional engine building knowledge and making sick horsepower out of sb chevys,but he did so by viewing the whole as a system.

bad67ls

iTrader: (2)

i just did my plugs and same issue. ls2 with vic jr. the carb pad isnt machined flat, and i am starting to wonder if i am pulling air at some runners too. ive heard of people getting vic jr's and the grooves for the orings at the runners are deeper on one bank than the other.


i am ready to throw this piece of **** in the garbage. what a joke edelbrock has become.

and for those that dont know, this is after getting 2 intakes boxed wrong. right number on the box, wrong intake in it.

speedtigger

iTrader: (16)

Look at the design of a single plane intake. These type of problems are inevitable with that type of runner volume variation.

bad67ls

iTrader: (2)

i never had a problem like this with my old 23* vic jr on my 357...

speedtigger

iTrader: (16)

You also had siamese intake ports too. That diminishes the cylinder to cylinder port volume variation.

VIPERSLYR

I'm also having the same problem with my fathers ls1 coupe we have the gm performance carb intake and the passenger side plugs are always rich and the drivers side run nice and clean any ideas how to fix this problem

james41

I live in the same town that Brodix has their main office as well as their manufacturing facility and after working on some of their intakes a few years back I asked questions about the purpose and uses of their turtles.If you don't know what I'm talking about it is a small cast aluminum fixture that is placed in the bottom of the plenum and epoxied there to help with fuel distibution problems.All single plane intakes have some problem with this to some degree.I learned from working with brodix that there are some tricks to getting them to flow more equally to all cy;inders.A tapered 4 hole spacer is said to help some.You also may have a small air leak on one side of the intake as a prior poster on here had issues with o-ring groove depths.Try the easiest and cheapest fix first .