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JusticeForPhat · 10-15-2003, 03:45 PM

I have some experience in this department, though the turbo Honda F3 I helped build ended up in a small car not a bike.

First thing first, your stock compression ratio is way too high to run any significant boost. On the F3 we had Arias make us some custom pistons to lower the ratio to 9:1. This is the ideal way to do it but its pricey as hell. With my orginization's discount it was still like 600 bucks. You could go the route of a thicker head gasket but it is no where near as consistant as the pistons.

Next thing: the stock head doesnt like 15 PSI pushing on the valves. You need to respring and reshim all the valves. This is a pain in the ass, since you need to surface grind all the shims to spec. Overall not too bad but time consuming as hell. You also might want to consider a better cam at this point.

Next: engine management. An F3 is carbed with computer controlled spark. This all got ripped out and got replaced with a Haltech E6A engine computer to control spark and fuel. We designed our own intake and fuel delivery system to take advantage to this. This requires that you get the bike on a dyno though to tune it, as there are no existing maps for this configuration. With your GSX-R you might be able to get away with a piggyback computer though to do the tuning, and a good 02 sensor.

Next: Exhaust. You need to make an exhaust header with the appropriate mounting flanges for the turbo, and that will fit in your bike.

Next: Turbo. We used an Aerodyne variable geometry turbo that was mapped for our application. Garret hybrids are very popular for bikes though.

We used a small intercooler with custom endtanks, however I see very few bikes with intercoolers. Some use water injection though to various degrees of sucess. You also will want to beef up the clutch. We went with a carbon kevlar unit that held up pretty well.

Overall the turbo bike is kind of a neat project. Due to regulation of our sanctioning body we need to use a 20 mm restrictor so we made only 115 horsepower and I think 75 ft-lbs of torque. Unrestricted I have seen numbers as high as 200 horses on 104 octane. Some Hayabusa's have broken 400 horses with the correct setups. Goes from 0- greasy spot on the pavement in about 2 seconds.

Your a little far away but there is a shop in South Philly where I get my parts from whose sole business is turbo-ing drag bikes. I'll see if his webpage is up.

10-15-2003, 03:45 PM	#7 (permalink)
JusticeForPhat Crazy Location: Philly	I have some experience in this department, though the turbo Honda F3 I helped build ended up in a small car not a bike. First thing first, your stock compression ratio is way too high to run any significant boost. On the F3 we had Arias make us some custom pistons to lower the ratio to 9:1. This is the ideal way to do it but its pricey as hell. With my orginization's discount it was still like 600 bucks. You could go the route of a thicker head gasket but it is no where near as consistant as the pistons. Next thing: the stock head doesnt like 15 PSI pushing on the valves. You need to respring and reshim all the valves. This is a pain in the ass, since you need to surface grind all the shims to spec. Overall not too bad but time consuming as hell. You also might want to consider a better cam at this point. Next: engine management. An F3 is carbed with computer controlled spark. This all got ripped out and got replaced with a Haltech E6A engine computer to control spark and fuel. We designed our own intake and fuel delivery system to take advantage to this. This requires that you get the bike on a dyno though to tune it, as there are no existing maps for this configuration. With your GSX-R you might be able to get away with a piggyback computer though to do the tuning, and a good 02 sensor. Next: Exhaust. You need to make an exhaust header with the appropriate mounting flanges for the turbo, and that will fit in your bike. Next: Turbo. We used an Aerodyne variable geometry turbo that was mapped for our application. Garret hybrids are very popular for bikes though. We used a small intercooler with custom endtanks, however I see very few bikes with intercoolers. Some use water injection though to various degrees of sucess. You also will want to beef up the clutch. We went with a carbon kevlar unit that held up pretty well. Overall the turbo bike is kind of a neat project. Due to regulation of our sanctioning body we need to use a 20 mm restrictor so we made only 115 horsepower and I think 75 ft-lbs of torque. Unrestricted I have seen numbers as high as 200 horses on 104 octane. Some Hayabusa's have broken 400 horses with the correct setups. Goes from 0- greasy spot on the pavement in about 2 seconds. Your a little far away but there is a shop in South Philly where I get my parts from whose sole business is turbo-ing drag bikes. I'll see if his webpage is up.