I need help bad!!

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Very good place to start, the basics!!! is it solid lifter or hydraulic cam? if hydraulic loossening them up will help low end also you may need to shim the rocker arm shafts if you dont have adjustable rockers
Jonnylightening said:
Were gunna try the valves. Sounds kinda like a shotgun when at idle and gets alil worse when revved
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waggin said:
if it has a solid lifter cam .022 on intakes and .026 on exhaust valves will wake her up......Just sayin :)
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at least 18 and 20 like mine....12 ,it might be grinding that thing every time it runs....
 
273 said:
Is it a new carb, freshly rebuilt or been sitting around?

and 850 ain't too big for your engine.
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IMO 850's way too big for what he's got and the rpm range it needs to run in even if it was set up perfectly. Is the M1 a single plane? Is the air door adjusted properly on that carb (Thunder AVS?)? If there's not enough airspeed when the throttle is cracked and the secondary air door is too lose it will stumble bad.
If a normal head gasket was run and estimating the chamber size around 81ccs(probably larger than that...) I'm coming up with around 9.1:1 assuming the deck height was blueprinted to 9.98. Normally they are much taller than that. So if the deck had a clean up cut it's still probably closer to 8.5:1 than 9. If the heads were not milled a bit and nailhead valves used, the chamber size is probably larger than 81 (they ussually start around 84-85) which would lower it even more. So it's all a mismatch. It will be hard ti tune with the parts you have, and if you really want it to wake up lower down the cam will need, and the carb may need to be replaced.
 
Didi you degree the cam? random 4 degrees may be putting that way off. Check your valves as recommended. If it still stumbles, check your chain/cam timing and degree your cam.
 
I'm with Moper. 850 is too big. Whether that's your problem is another thing, but it sure ain't helpin.
 
The easy way to tell if the carbs to big how many inches of vacuum does your engine have at WOT more than 1.5 the carbs too small if less than your given up some drive ability and low end torque for more top end not biggest deal in a race car you don't want to see less than 1" of vacuum. All 2 barrels are rated at 3" and 4 barrels are rated at 1.5" so a six pack is less than a thousand cfms at 1.5" of vacuum.
 
Just curious get her all setup and working good?
 
Big thanks for the help guys finally got a chance to post. Had her out and got 3 hooks in so far. After swapping out the 750 eddy(w/spacer) to my 670 holley (w/o spacer) it really woke her up. I might try the 750 again w/o the spacer just to see if the spacer was causing the problem. I found out that the mounting ears were alittle rounded where they should have been flush. I'm not sure but just thinking that maybe it was leaking alittle vacuum. However for being my 2nd motor build (1st BB) I couldn't be any more proud.
 
That cam doesn't sound right at ALL. You say "235 @.050 and 264 advertised". That's not enough advertised duration to equal [email protected]. Something's up with that.
 
the intake valve should be set around 24 thou and the exhaust at about 28 thou i bet it will at least rev quicker
 
I had same problem had a worked 360 with 484a cam put a 536 cam in and lost all bottom end turns out converter is to tight I dunno what u have I would try a 3000 stall
 
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