New 440 build issues
- Thread starter chermik1999
- Start date
Im at .101 primary and .110 sec.
Maybe change carb jets and rods back to factory, that it was calibrated to have correct AFR at sea level and work your way down, according to elevation. There is probably a recommendation in the book. It's not about getting alot of fuel, but the correct mixture of air and gas into the engine. Extreme changes rarely work. It would be easier with a dual plane intake manifold.
Ya was at factory yesterday and same thing. Still wanting more fuel WOT. I'm OK to make the change. With low vacuum, I doubt I can get this tuned right.
The initial 18 AFR is probably the accelerator pump not delivering a big enough shot. See what squirter you have and step up to a bigger one. If the rod isn’t on the inside hole nearest the pump you can move it to that to get a bigger shot, but it will be of less duration and that’s why a bigger shooter is a better approach.
The low vacuum issue is manifold vacuum which primarily affects idle and initial transition circuits. Once you are in the throttle and the engine is sucking air the carb secondary and primary circuits are pulled in and they operate off of Venturi vacuum which is more a function of carb throat size, rpm, engine size, and air velocity in the throats. So this shouldn’t affect your tuning out that lean condition under full throttle.
No no. That's when I mash the pedal. Initial at idle is around 13.6-14.1. Light throttle and cruising around 12.8- 13.2
K..just checked again after moving to fartherest hole on pump. No stumble now.
13-13.4 ish idle. When I try a brake stand to say 3k, pulls nice like loads of power. Problem is when I'm on the road and mash it, it goes lean and power loss. Wanted to go round 3000 then after that slowly dies.
Like a cammed engine with 2.76 gears. No nothing out of the hole. Rolling say 40mph, hit it and pulls hard but seems wants more something. Weird....I'll put the brawler back and see what I get.
I didn't have an AFR before with it. Now I can see what's going on a bit.
Thanks a bunch for the support..all of ya'll out there...
gtxrt
Well-Known Member
is the transmission kicking down to a lower gear at wot ? were the heads ported for the 2.14 1.81 valves in the 516 heads ? heads could be a big problem if not done right even done right with the bigger valves and porting it has to hurt torque. the 800 AVS2 won't be causing you these problems unless the floats are out of spec. did you check the floats ?
As someone said, maybe it's installed retarded? Who installs without degreeing? I'm upset.....well I'll swap cams. But gonna degree this one first just to see.
Yes...KD works. I was wrong. They're 906 heads and yes we're ported some and large valves.
Floats as per the book..7/16"
Actually now I have the number. Are 346 heads 79cc.
gtxrt
Well-Known Member
there are open chamber heads they can't be 79cc can they ?
gtxrt
Well-Known Member
a new cam would be good with high lift and less duration @.50 the 509 was [email protected]. it will get your cylinder pressure higher and more torque. plus knowing it's degree in. sometimes the timing chain and gears are messed up.
Closed chamber...
Ya bad cam all around for this. Like was saying, not doing 4.10 and 4500tc...nope
gtxrt
Well-Known Member
am confused the 346 was made from 1971-1973 and are opened chambered.
gtxrt
Well-Known Member
not sure the cam is your only problem. 509 should turn on at 3500-3800 rpms. if i read right your running a 3500 rpm converter with 3.23 gears that's not good.
Yuup...ur right ans correct. And 3500 stall wont.kick in that high either cause the torque curve on engine is meased. Not good.
Matter of fact when I do a off line launch it only runs to 3000...cam just won't work. Maybe 20 hrs so will try to sell it and lifters...lol.
My engine guy knew that. But that's why he's sending the new cam etc...just more work for me. But appreciate his support all things considered.
But I'm his defense, he was getting advice from a race engine builder that built my tranny. He wasn't listening.....lol
Similar threads
