MEAT
Expert
HOW IS IT POSSIBLE TO REDUCE SQUISH BY ADDING A THICKER HEAD GASKET?
TURBO TIME
Pro
WORDS FROM CORKY BELL:
A VARIETY OF METHODS EXIST TO CHANGE A COMPRESSION RATIO, ALMOST ALL ARE UNACCEPTABLE. THE CRUX OF THE MATTER IS UPSETTING THE SQUISH VOLUME AROUND THE RIM OF THE CHAMBER. A CHAMBER IS DESIGNED SO THAT THE CHARGE IS PUSHED TOWARD ITS CENTER AS THE PISTON REACHES TOP DEAD CENTER. THIS IS POSSIBLY THE STRONGEST DETERRENT TO DETONATION DESIGNED ITO THE SYSTEM. IT IS POSSIBLE THAT MODIFYING THE SQUISH VOLUME COULD RESULT IN A 7:1 MOTOR PINGING WORSE THAN A 9:1 MOTOR WITH THE PROPER SQUISH VOLUME. APPROCHES TO LOWERING THE COMPRESSION RATIO THAT DO NOT WORK ARE THICKER HEAD GASKETS AND SHORTER CONNECTING RODS. ANOTHER RULE IS A TURBO ENGINE SHOULD NEVER BE REDUCED TO A LOW COMPRESSION SLUG, MEANING IF YOU ARE NOT DETONATING WHY DROP COMPRESSION, AN ENGINE RUNNING 15PSI ON RACE FUEL WILL SMOKE AN ENGINE RUNNING 15PSI WITH LOWER COMPRESSION ON PUMP GAS.
A VARIETY OF METHODS EXIST TO CHANGE A COMPRESSION RATIO, ALMOST ALL ARE UNACCEPTABLE. THE CRUX OF THE MATTER IS UPSETTING THE SQUISH VOLUME AROUND THE RIM OF THE CHAMBER. A CHAMBER IS DESIGNED SO THAT THE CHARGE IS PUSHED TOWARD ITS CENTER AS THE PISTON REACHES TOP DEAD CENTER. THIS IS POSSIBLY THE STRONGEST DETERRENT TO DETONATION DESIGNED ITO THE SYSTEM. IT IS POSSIBLE THAT MODIFYING THE SQUISH VOLUME COULD RESULT IN A 7:1 MOTOR PINGING WORSE THAN A 9:1 MOTOR WITH THE PROPER SQUISH VOLUME. APPROCHES TO LOWERING THE COMPRESSION RATIO THAT DO NOT WORK ARE THICKER HEAD GASKETS AND SHORTER CONNECTING RODS. ANOTHER RULE IS A TURBO ENGINE SHOULD NEVER BE REDUCED TO A LOW COMPRESSION SLUG, MEANING IF YOU ARE NOT DETONATING WHY DROP COMPRESSION, AN ENGINE RUNNING 15PSI ON RACE FUEL WILL SMOKE AN ENGINE RUNNING 15PSI WITH LOWER COMPRESSION ON PUMP GAS.
MEAT
Expert
GREAT REPLY TURBO TIME! IS THERE A BOOK A PERSON CAN BUY TO EXPLAIN THE FUNDAMENTALS OF TURBO CHARGING? YOU ANSWERED ONE OF THE MANY QUESTIONS THAT I HAVE. I WANT THE BEST THROTTLE RESPONSE AND HIGHEST HP POSSIBLE WITH PUMP GAS.IS RUNNING LOWER BOOST WITH HIGHER COMPRESSION THE ANSWER OR HI BOOST WITH LOWER COMPRESSION ?
TURBO TIME
Pro
MAXIMUM BOOST BY CORKY BELL, A FANTASTIC BOOK THAT EVERYONE INTERESTED IN TURBOS SHOULD READ.
I'll second that.
kip
Pro
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bender unit,,,, high boost and 92 octane fuel does not mix, again the installer suggested that reg gas with octane booster would be just fine,,,, it was for the first 100 feet,,, than POW !!@_$95_)@(*)&(^$$ and out of the cloud of white smoke of burning atifreeze rolled the warrior to a dead stop..
snowy1
TY 4 Stroke Guru
so if I understand this right if you want the most power you can and don,t mind spending the money on race fuel we should leave our motors stock and run the best fuel we can get now how much boost can we run with strait race fuel on a stock motor at 10,000 ft. and are the blown head gaskets from excess pressure cuased by boost or from detenation, I don,t plan on ever running strait pump fuel
kip
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with two years racing 13-14 lbs ob boost with 112 octane at 1000feet, no problems..... headgasket problems seem to occur at or near 18lbs..... now at your altitude, i have no, repeat no experience ... yet i would believe you could get by with 4-7 points less octane..... on the bender stage III turbo, Terry had mega problems, at 15-18lbs again no problems.... when pushed to 22lbs.... problems,, leakage of fluid outside the engine... I would check with the Mountain tubo guys to see the ocatane they require ...
snowy1
TY 4 Stroke Guru
I don,t plan on going over 15lbs I am running 50/50 vp110 and 92 octane right now at 10 to 12lbs over that I will run strait we are losing almost 5lbs of atmispheric pressure at 10,000 ft. which I would think if you ran 10lbs of boost at sea level plus the atmospheric pressure 14.7= 24.7 total psi of air pressure so at 10,000 we should be able to run close to 15lbs boost just to equal what they run at sea level at 10lbs. any thoughts on this.
TURBO TIME
Pro
15 PSI WITH STRAIGHT VP110= NO PROBLEM, I HAVE BEEN RUNNING 12-14 PSI + NOS ON SUNOCO 110 AT 8-9000 FT FOR 2 YEARS WITH NO PROBLEMS AT ALL.
snowy1
TY 4 Stroke Guru
TURBO TIME: is that with the stock motor no head gasket if so thats the kind of info. I am looking for thanks.
kip
Pro
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turbo time... which n20 system do you have ? I just bought a boondockers, yet am confused as to how the system can add or contribute to the presure signal to the carb when it is tied into the pieto presure line...
TURBO TIME
Pro
SNOWY, THAT IS ON A BOX STOCK MOTOR.
KIP, YOU ARE RIGHT, ONCE BOOST PRESSURE OVERCOMES THE PRESSURE FROM THE NOZZLES THEY WONT BE CONTRIBUTING TO RICHEN THE CARBS, ALSO UNLESS YOU INSTALL VAC. CHECK VALVES INTO THE SIGNAL LINES THE SIGNAL FROM THE PITOT TUBE WILL BE BLED OUT OF THE NOZZLES AND WILL RESULT IN A LEAN CONDITION, THE SIGNAL FROM THE NOZZLES DOES CONTRIBUTE UNTIL BOOST IS REACHED FOR USE OUT OF THE HOLE, IF YOU WISH TO USE IT WIDE OPEN JUST RICHEN THE MAINS 2-3 STEPS FOR THE 40HP SHOT, THIS SETUP STILL SHOWS PLENTY RICH ON THE O2 GAUGE FROM A DEAD STOP TO WIDE OPEN WHEN USING NOS ALL THE WAY THROUGH.
KIP, YOU ARE RIGHT, ONCE BOOST PRESSURE OVERCOMES THE PRESSURE FROM THE NOZZLES THEY WONT BE CONTRIBUTING TO RICHEN THE CARBS, ALSO UNLESS YOU INSTALL VAC. CHECK VALVES INTO THE SIGNAL LINES THE SIGNAL FROM THE PITOT TUBE WILL BE BLED OUT OF THE NOZZLES AND WILL RESULT IN A LEAN CONDITION, THE SIGNAL FROM THE NOZZLES DOES CONTRIBUTE UNTIL BOOST IS REACHED FOR USE OUT OF THE HOLE, IF YOU WISH TO USE IT WIDE OPEN JUST RICHEN THE MAINS 2-3 STEPS FOR THE 40HP SHOT, THIS SETUP STILL SHOWS PLENTY RICH ON THE O2 GAUGE FROM A DEAD STOP TO WIDE OPEN WHEN USING NOS ALL THE WAY THROUGH.
MEAT
Expert
Just wondering how much boost / hp difference between front and rear mount turbo ? Does the under hood heat make that much of a difference in performance?
snowy1
TY 4 Stroke Guru
thanks for the info guys its a great help snowing hard here now hopefully it will let up enough tomarrow to go for a ride,
