Ok, lets try this another way that won't violate the rules I have a turbo 400 behind a chevy 350 in my 58 apache the problem is im 'turning 3500rpm at 40 mph with 3.55 rear gears and a 2200 rpm stall converter with 26 in tires, Tach has been changed to rule that out and rear gearset has been verified Trans hits all 3 gears perfect, truck runs perfect and smooth, trans guy says converter converter guy says trans. Trans has been rebuilt and problem still persists Any thoughts
Sumthin's very off..! Are you sure of each thing - 1. Gear ratio ? You say it's been verified, how ? Actually seen the numbers stamped on the ring gear (or counted the teeth). Turning the driveshaft and watching the tires DOES NOT count. 2. "Advertised" converterter stall ? Have you actually run the engine up to verify the brake stall speed, (brakes on pedal on the floor) ? Note, make sure the engine is warm. 3. Speedometer "actually" correct ? I know, the feeling at 40mph is different from 65 or 70mph...but..!? 4. Tire size...metric dimension or...? Sorry, had to say it..! Still... There's no magic here. All verifiable info. I doubt the trans. is slipping. It would be pretty obvious, and would probably surge some amount. Also would change hitting the gas hard, the rpm would go up before the truck moved much faster. Mike
Yes gearing is accurate would have to be 6.10 gearing to turn that many rpm, speed has been checked by gps several times, and is accurate And tires with a tape measure are 26.25 in tall Tach has also been checked and is within 50 rpm of my friends $1000 digital tach
There is no surging and it will put you back in the seat with only moderate throttle input, Trust me ive 'gone through this thing head to toe and im as confused as they come
if everything is right, then it's working fine. There really isn't much we can do without driving the car (truck) to see what's going on....
When I had the crazy loose converter in my truck, it really winged the tach going up a hill and if you lightened up on the gas pedal at say 45mph if would finally catch up to the converter and the rpms would drop. Now of course if you gave the gas it would try stalling and flash the rpms much higher. Did you jack it up and make sure you don't have a wheel bearing or brake that is to tight, or possibly the back side or top of tire rubbing on something causing drag ?
Have checked bearings and brakes I'm thinking tct I'm going to swap it tonight but its an fti converter so not junk
That's my plan I'm putting in an AutoZone special stock converter tonight I would just think that a bad converter would feel like a Slipping transmission
I have ran a few 400's and have always used a stock converter. I usually run about a 29 inch tall tire and have not had rpm problems to date? Mine have been in relatively light 32 Fords.
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