i rcently ugraded my combo,cam and heads.est. 600 plus hp.it flashes at 3500.with the previos combo it would,nt drag the motor down much and you had to push on the gas to get it moving. but now when it goes into gear i have to be on the brakes and the motor boggs down.not to the point of stalling but when i take my foot off the brake it takes off.its a 9 1/2 in a rb.could i need a looser vert or should i look at another cause?its a street strip application.

Street strip combos need a converter based on how much you want to favor the street or strip. Do you want it to approach lockup early for street? Or are you willing to tolerate a loose converter to go fast? The more stall you have up to about 85 % of your shift point rpm, the faster you will go. I made gains going to 6400/6600 flash with a 7100 shift point. I make within 5 hp of max at 6300 rpm. Obviously, you probably don't want to push it that far. But getting the motor up over peak torque into where the motor is close to peak hp is going to net you more hp to the tires ON AVERAGE , which yields best ET. So pick your own characteristics and have fun!

i think it would be nice to have a diesel auto with the lock up converter to adapt to a bigblock or put the parts in a rb case if they kept them similar.
i talked to someone and the old non overdrive diesel was a 727. if that had lockup then maybe that could work if lockup higher stall converters are not as much as going lenco or g force pull speed.

my lupo flashes at 5400 to 5600.i do not drive it on the street but i have friends that do with converters around 5000 flash or a tad higher with 4" small blocks and they seem to not complane.

The diesel 727 never got a lockup converter and the diesel OD trans didn't get lockup until '94. The diesel lockup converter is larger in diameter and I don't think it would fit in any BB adapter bellhousing (like the Ultrabell).

Is it a different trans. The pump press might be alot higher. I've seen a big difference in stall depending on the pump pressure.

same tranny and vert.