Thanks for your comment. Normally for supercharged applications there is a throttle body before the supercharger. However I wanted to maintain the sharp responsiveness of individual throttle bodies . A turbo flowing air into a positive displacement supercharger is not restricted by the supercharger but there is restriction if a supercharger flows into a turbo. The key to my setup is having a large bypass or blow off valve after both the s/c and turbo so that all boost is dumped whenever it's not required. I have just copied the lancia S4 set up but I am dumping boost to atmosphere rather than feeding it back in pre s/c. You also have to have a soft (1 or 2 psi) spring in the blow off valve to allow boost to escape in part throttle (cruise) conditions.
I forgot to also reply to your statement that no, there isn’t a throttle body in front of the supercharger. I have kept the original throttle bodies (1 per cylinder ) and the original 16v manifold for the responsiveness. So ... like this.. air filter...compressor....a/w intercooler... waterinjection and into supercharger...blow off valve....second a/w intercooler ....second water injection...original manifold....original throttle bodies per cylinder into engine. Phew !
Well done. Love it. Only thing that didn't make sence was air path from turbo to super charger. On an eaton fitted to say a BMW Mini Cooper S R53 you have a throttle body before the supercharger inlet. So in your cars case it should be turbo outlet to water to air. Through water to air into throttle body before the super charger. Super charger outlet to water to air then in to the air manifold.
well.... you need forged pistons and you need to lower the static compression from factory standard 9.8 or 10"1 ? down to something lower like 9.3 . This depends on what fuel /boost you want. 98 octane or E90 Ethanol. In twin charged state you could stay with current compression and ethanol fuel as long as the tune is good. Water injection helps alot. The crank is standard. I had some near side inlet porting done to both heads for better flow. What's imperative is that you precisely measure your head volume from one head to the next to ensure that each head produces the same burn characteristics otherwise mismatched air fuel ratios under load conditions will happen and one head will run lean and then BOOM detonation. The gearbox has a 20mm? aluminium sump plate instead of the standard pressed steel sump. The clutch is an aftermarket VW 8" single disc Kennedy stage 3 drag clutch. The engine will produce probably 420 HP at 7000 but whats the point... the tyres break free at 4000. The secret is probably the pulse effect after the exhaust ports which is what the PD supercharger provides and probably the way I welded up the turbo manifold. I am proud of the fact that I can keep the original throttle bodies and keep the responsiveness they provide. I also have a turbine backpressure to inlet ratio of 1.2:1 so the COMBINATION of the supercharger and the turbine housing size work very well.
Thanks for your comment. Normally for supercharged applications there is a throttle body before the supercharger. However I wanted to maintain the sharp responsiveness of individual throttle bodies . A turbo flowing air into a positive displacement supercharger is not restricted by the supercharger but there is restriction if a supercharger flows into a turbo. The key to my setup is having a large bypass or blow off valve after both the s/c and turbo so that all boost is dumped whenever it's not required. I have just copied the lancia S4 set up but I am dumping boost to atmosphere rather than feeding it back in pre s/c. You also have to have a soft (1 or 2 psi) spring in the blow off valve to allow boost to escape in part throttle (cruise) conditions.
I forgot to also reply to your statement that no, there isn’t a throttle body in front of the supercharger. I have kept the original throttle bodies (1 per cylinder ) and the original 16v manifold for the responsiveness. So ... like this.. air filter...compressor....a/w intercooler... waterinjection and into supercharger...blow off valve....second a/w intercooler ....second water injection...original manifold....original throttle bodies per cylinder into engine. Phew !
Well done. Love it. Only thing that didn't make sence was air path from turbo to super charger. On an eaton fitted to say a BMW Mini Cooper S R53 you have a throttle body before the supercharger inlet. So in your cars case it should be turbo outlet to water to air. Through water to air into throttle body before the super charger. Super charger outlet to water to air then in to the air manifold.
I’m looking to build one like this off an 8v engine. What would it cost to get this done in a shop?
Hi, this build is nuts. im building a 33 and i want ot ask about the internals of the engine ¿are they stock?¿how good the engine stand the power?
well.... you need forged pistons and you need to lower the static compression from factory standard 9.8 or 10"1 ? down to something lower like 9.3 . This depends on what fuel /boost you want. 98 octane or E90 Ethanol. In twin charged state you could stay with current compression and ethanol fuel as long as the tune is good. Water injection helps alot. The crank is standard. I had some near side inlet porting done to both heads for better flow. What's imperative is that you precisely measure your head volume from one head to the next to ensure that each head produces the same burn characteristics otherwise mismatched air fuel ratios under load conditions will happen and one head will run lean and then BOOM detonation.
The gearbox has a 20mm? aluminium sump plate instead of the standard pressed steel sump. The clutch is an aftermarket VW 8" single disc Kennedy stage 3 drag clutch. The engine will produce probably 420 HP at 7000 but whats the point... the tyres break free at 4000. The secret is probably the pulse effect after the exhaust ports which is what the PD supercharger provides and probably the way I welded up the turbo manifold. I am proud of the fact that I can keep the original throttle bodies and keep the responsiveness they provide. I also have a turbine backpressure to inlet ratio of 1.2:1 so the COMBINATION of the supercharger and the turbine housing size work very well.