Zotoman
Well there are only a few of us that actually run or have ran multi engine vehicles I can give ya my wisdom “Don’t do it!” It’s double the budget, double the parts, double trouble, double fun and double the pain in the ass. Dolan has built and raced doubles but he really enjoys double talk and riddles. I really think he enjoys seeing people foolish enough to try it. You are correct double engines are only 75% total increase in hp but doubles torque. After all torque is what pulls 3 mile long trains, torque is what pulls stumps, and torque is what pulls heavy streamliners with moon gearing to record speeds. Since my liner is only 27” wide it is too wide to fit onto my bike dyno and is too narrow to fit any car dyno rollers I have found yet. So exact numbers still elude me. My motors put out 360hp and 165tq in a bike chassis each. So I figure I have bout 500hp and 325tq to the rear wheels. That’s small block Chevy numbers. That’s why we had to have billet trans made cuz we were ripping them out of the cases. Than we were just ripping the motor mounts off the motors, now we just snap drive chains like shoe laces. But were getting there. Soon well have all the bugs worked out (damn wet salt)
As for your question bout 8 or 16 cylinders, 8’s fire at 45 intervals to clock another to fire at 22.5 would be possible but not really necessary. Spend your time figuring out how to make a bulletproof flexible coupler that will handle 1500 lbs of torque that wont break the cranks. I couple my motors through the output shafts. the motors sync through harmonics. It’s like a tuning fork, when these babies sing its sweeeet. I currently own that Bob George liner you saw on the dirt. It was coupled through the crank primaries. Last year Bob Mooreland and the easy rider liner’s crew chief Keith Ruxton, spent a lot of time with crank leed and timing Bobs motors. I know what there crank phase is but cant say its kind of there secret. Don Vesco’s double bike liners always had the trans cut off of the front motors and linked crank to crank. Don always had chain or belt problems due to crank speed. The Rick Vesco twin Yamaha engine liner I own has both motors coupled to the output shafts cuz the cranks run twin blowers. The Ack attach liner is coupled at the rear wheel. The front motor uses a jackshaft to transfer drive to the right side and then back to the rear wheel with a chain. The rear motor is direct to the rear wheel. Metty’s bike is crank to crank just like all Harleys and Max Lamby’s Vincent is crank to crank via come pretty awesome gear drives. Probably the best coupling I’ve ever seen. All the double Harleys, the Vincent, and Vesco’s liners ran one trans and all have had major trans problems. All these bikes double the HP and TQ but run it through ONE trans that gives it up. I run 2 trans to half the torque loads, after a few motors and a few grand we finally have the trans worked out. I also run 2 complete systems. 2 motors, 2 ignitions, 2 ecu’s, 2 turbo's, 2 waist gates. I tried linking the turbo's once, when I lost a valve in the rear motor it took out the front and rear turbo. I changed that crap right back to 2 separate systems. I have no problems shifting both motors, Jimmy Odem had a shifting problem with the linked system on the Ack liner once, but I think they straightened it out as Noonan has yet to have a repeat of the miss shifting. If your thinking strongly about car motors you should talk to Rick Vesco about Dons experiences with the twin Offy’s or Rick White about the twin Hemi’s in his dad’s 400mph liner.
Man I gotta stop now, I can go on and on ‘bout doubles but both of my typing fingers are getting tired. Maybe all this typing ‘bout double engines will get me double points!
