Yet another weber 500 question

mgbv8 · Post by **mgbv8** » Tue Oct 02, 2007 6:55 pm

I know we have been here before.
I'm re jetting the carb weber 1404 for the new 4.6 engine.
Weber 500, blower cam (almost the same as Typhoon)

After a bit of checking, I'm going for :
086 on the primary
092 secondary
6347 rods
Silver springs.

Has anyone got this combo on at the mo? And does it work ok?
Thanks
Perry

Robrover · Post by **Robrover** » Wed Oct 03, 2007 4:26 am

That's pretty much what I'm running on my 4.6 though the rods may be different. I used the Edelbrock jetting kit to set it up on the road. However I was getting a stumble off idle which no jet/rod/spring swapping would cure so I got it checked on a dyno and guess what, the dyno operator confirmed I 'd chosen the right combination, which was unusual and a bit of a waste of money (dyno time aint cheap). The stumble was caused by mixing an Accel coil with Luminition, which the dyno failed to identify, but which I subsequently fixed myself by swapping in a standard Bosch coil.

This is with a Crane cam and big valve, very worked Buick heads. It seems to work ok, good idle, no flat spots and extremely strong mid range.

minorv8 · Post by **minorv8** » Wed Oct 03, 2007 7:03 am

Your rod choice seems quite rich, in fact 6552 is a bit rich in my engine. I believe I am running 6755 ones with Typhoon cam. I don´t remember which springs I have.

mgbv8 · Post by **mgbv8** » Wed Oct 03, 2007 9:34 am

Is your a 4.6 as well Minor?

CastleMGBV8 · Post by **CastleMGBV8** » Wed Oct 03, 2007 2:46 pm

Perry,

I think I would have a word with RPI and Real steel and see what they suggest for a 4.6 and or your nitrous kit supplier.

I think you about right on the primaries, but not sure about the secondary calibration, but if using gas you probably want to be a bit on the rich side to compensate so your 6347 might be spot on.

The base calibration is for engines in the 5.7 - 6.4L range so even those figures maybe too rich..

Kevin.

mgbv8 · Post by **mgbv8** » Wed Oct 03, 2007 8:41 pm

Thanks Kev.
I'd rather run on the rich side for nitrous use anyway.
But I'll talk to RS and RPI to see what they recommend.
Perry

minorv8 · Post by **minorv8** » Thu Oct 04, 2007 8:42 am

Is your a 4.6 as well Minor

Yep.

mgbv8 · Post by **mgbv8** » Fri Oct 05, 2007 7:22 pm

Thanks Minor
I'll try those rods as a starting point then.