Mopar Muscle Association UK

Great looking car

i dont know if there are any six pack tuning experts on here - but i would i thought you could change the power valves ( i guess the outboard carbs have a power valve?) and put a lighter spring in the diaphragm ?

No power valves or enrichment devices in the outboards and that is the set up's Achilles heel.

You get the legendary "Stumble" as you have just opened up 2 x 500 cfm carbs and not added any fuel with them.

The engine soon overcomes this, but it is always noticeable if you floor it hard.

hey folks, thanks again for the positive comments. well i've done the cam and the car is much better,
even on these very cold mornings ,two stabs of the throttle and it fires up straight away and ticks over on its own,
set the six pack and kickdown up as stock, it runs and drives great, have an air leak on the rear carb , but will sort that soon,
now its not a multi feet dance to stop, having to blip the throttle to stop it from stalling while slowing down in neutral .
the brakes could be better, but now i've 17 inches of vacuum at idle instead of 4.5 I can put power brakes on,
that's next weeks project, need a bit of heat in my garage first,,

also have to sort out the colour of my engine, had the correct shade mixed for the valley gasket and new rocker boxes, but completely the wrong colour for the rest of the engine, oh well something else to deal with,

hemi472 wrote:Great looking car

i dont know if there are any six pack tuning experts on here - but i would i thought you could change the power valves ( i guess the outboard carbs have a power valve?) and put a lighter spring in the diaphragm ?

the middle carb does all the normal work, but its basically an eco-carb and does not like low vacuum

there are ways round it with different base plates etc, but to be honest it was not fun round town and did about 3 to the gallon!!!!

it sounds fantastic now as well

Pete wrote:No power valves or enrichment devices in the outboards and that is the set up's Achilles heel.

You get the legendary "Stumble" as you have just opened up 2 x 500 cfm carbs and not added any fuel with them.

The engine soon overcomes this, but it is always noticeable if you floor it hard.

That's part of the charm of a Six-Pack Pete. The little 'stumble' then it's like getting hit around the head with a baseball bat. It's fabulous, it's what makes the Six-Pack special, - more exiting sometimes than flooring the more progressive 2 x 4's on a Hemi.

Yea six pack set up's are just a poor design, I guess it was down to cost. if the outboards had accellerator pumps and the carbs were canted or mounted sideways it could have been a tuners dream, rather than the compromise it is.

Sweet looking car. Very menacing.

been meaning to add a few more pics...

Is DaveR not around any more?



I don't remember the Challenger having any stumble.

Dave isn't a member these days Sandy. His carbs were heavily modified in the States, very skilled work. I did look to replicate the modifications when I was tuning Jems Belvedere but decided I had neither the equipment nor the watchmaker level of skill required.

Hi Blue,

I didn't realise Dave wasn't a member any more.

Yes, Linda took the carbs and manifold across to the U.S. on a plane and brought them back on her return after the work had been done.

The Challenger did go well (not as well as a V6 Buick of course, but not bad for a Mopar )

All the best
Sandy

hi folks,

finally got round to fitting the new servo, master cylinder and bias valve, my car at some stage it had been fitted with discs on the front but still had the original drum / drum bias valve, but had been updated with a disc / drum manual master cylinder.

the brakes were never great , in fact my old roadrunner with drums all round stopped better ... LOL

anyway I did my research and found the bias valve of a '78 Cordoba had all the correct fittings to suit my car that had a drum / drum bias valve, it fitted with little problem, other than the headers being a pain in the arse to work round,

the master cylinder / servo combo fitted very well with new firewall gaskets etc, had the correct rod and fittings and was adjusted perfectly to drop straight in, just had to make the lines from bias valve to master cylinder,

a very straight forward job after bleeding, and checking the adjustment on the rear shoes,

I cant believe how much of a difference it has made, the car now drives more like a modern car, very little effort needed to stop, and has made it more of a joy to drive,

nice one Jay

heres a few under side pics..










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