TOPIC: Whats the diff from a 1500XS and a t2 Twister?

Thought they were one in the same but guess not, is it the 6 carbs? if so does the 1500Xs have 3?

Bill,
Yes, the Twister II and Twister IIx have a non power-ported block like the first edition 1400, but has (3) intake ports rather than the common (2) intake ports per cylinder.
It also has a unique crankshaft & firing order that tunes (3) cylinders to the other (3) to give better performance.
It also has a unique crankcase cover that has a set of (7) pedal 'pyrmid' style reeds (14 total) per cylinder, and (6) very large carburetors.
The carburetors are TC-3A and very similar to those carbs found on a large Force outboard motor.
They will turn 7600 RPMs for 8 hours +/- straight and were used against the Super Strangler OMC in marathon races.
The 1500xs is simply a 1500 with slightly tweeked porting and a short (15") mid-housing. It has the common style (3) carburetors.
WMK-11, WMK-14, WMK-19, and one other number I can't recall right now.
They were estimated at 165 hp and their original switchbox (A-25) did not have a rev limiter like common inline-6 switchboxes.
The 1500xs also had a unique lower unit that has its water intake holes on the underside of the gear bullet.
The T2 & T2x used a short (11-12" mid-housing) and a super Speed master lower unit (SSM)
I have one T-1, one T2x & a couple 1500xs Mercs.
The T-1 was a 1350 with unique intake ports and a very unique exhaust system, DSH & SSM.
Thom

Question for Thom, or anyone else that can answer....

What were the HP ratings(at the crank) for the Twister series of motors?

Sure would love to get my hands on one of those someday...

Thanks Thom for clearing up the confusion, lol. Great info and didn't think there were so many versions. Thanks for the pic's also they always help:) This explains how the 6 carbs fit, no reed blocks...interesting! If you have a pic of the 'pyrmid' style reeds' would be interesting to see its design

Here's some Mercury specs on the T-II and the T-II-X, can't recall where I gleaned this from but there it is. What I find interesting is that Merc doesn't state HP figures but if you look at the advertised fuel consumption for the T-II (21 GPH) and the T-II-X (23 GPH) and calculate using the Good Ol' Forumula of GPH/10=Crankshaft HP, 210HP and 230HP are some pretty incredible numbers!!!!

Couldn't say what, if any inefficiencies would have skewed those numbers but maybe one of the Old-Time Racing Guru's have dyno-run info. Definitely nasty motors and they're moving a ton more fuel-air mix thru them than a stock motor.

When the Good Dr. Thom gets his replica-racer in the water, we're gonna have to have the Hi-Test fuel truck standing by for a reload after just a few laps around the lake!!

Cheers........ed

p.s. I Googled up an interesting thread on Screamandfly:

www.screamandfly.com/showthread.php?68983-twister-2-hp