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V8bug
05-05-2006, 04:29 AM
I have a 283 sbc around 9.5:1 cr with a summit 1103 cam, 214/224 .442/.465.
It has a tpi intake and megasquirt controlling fuel and ignition. I got the car to idle inbetween 900-1000rpm, any lower and it gets unstable and stalls.

when I drop the car into any gear the rpms drop to around 500rpm and the engine stumbles for about 4 seconds and dies. To get it to run in gear I either have to raise the idle to about 1200rpm (but then it makes violent clunk when shifted into gear) or I have to catch the engine before it dies and keep on the gas.

This is no way to have my car operating. I have thought about changing the cam and decided against that. The torque converter in there now is a summit
SUM-G2700 that they say has a flash stall of 1700 rpm, and a stall between 1500-1900, feels like a stocker though?
should I buy a converter with more stall? summit sells one with a flash of 2000 and a stall between 1800-2200 i think.

The car in question is a 71' vw bug with a ford 9" and 2.75 gears, can't weigh more than 2500 lbs

any help would be great!!

V8bug
05-05-2006, 05:00 AM
Oh yeah forgot, desktop dyno says about 300hp @5500
and 329ft-lb @4000

sounds a little much to me but jsut to give you an idea of the power band I guess.

This car is going to be a street machine too

V8bug
05-06-2006, 06:31 AM
I have the engine tuned as good as it is going to get and I am still having problems with the transmission. th350 with a summit converter flash stall 1700rpm.

With the engine idling at a 1000rpm or so I drop it into any gear and it drops to 500rpm and dies. If I quickly get on the gas, I can keep it from stalling but the rear tires start spining!! I mean I was dragging my front tires down the garge in reverse and almost ripped the door off to keep it running. Oh yeah and it is spinning the tires right around 1000rpm! I mean stall speed my a$$ this thing is hooking up right away. It reminds of a baretta I had when the torque converter control solinoid went bad and the converter locked up, except my trans is a none lock up.

other problem with this trans is that when I put it into drive it takes a second or two until it engages and stalls the engine. The shifter linkage might not be adjusted perfect though?
Also I bought this trans for a $100 from a buddy's friend who said it was good. I have done nothing to it.

any ideas/suggestions anything would be great!

Steve Chryssos
05-07-2006, 04:17 AM
Very strange and interesting condition if it is somehow related to stall speed. As far as I can decipher from your posts your converter's stall speed is 1000 rpm and yeah, that is too low. While rated stall speed varies with application, I do not see your 1500-1900 converter stalling that low.

I would be looking at your fuel injection's load sensor before diving into a new converter (i.e. MAP sensor)--Especially since you can't get the engine to idle below 900rpm. The converter MIGHT be tugging on the engine at 1000 rpm OR a fuel injection problem MIGHT be preventing the engine from generating sufficient power required to oppose the load generated by your drivetrain. If you have some sort of load sensor issue, it might not reveal itself at idle (out of gear) since there is no load on the engine. So double check the load sensor or the relationship between the load sensor and the TPS sensor. My money is on the fuel injection.