That's awesome Greg. I hear that one of your SC kits is now running on a GoTech!!! Nice! Sure solves the fueling problem - dyno and A/F meter hooked up will tell you right away...!
Do you have the power vs air/fuel graph print-out from the dyno on your car? Can you post it please!?
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junglejustice
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Greg,
Would moving the throttle body to the intake side of the SC reduce the whine? The whine is loudest at the air filter since it's open to the SC.
People with MAP based EFIs have a huge advantage in this respect. I think you can have the air intake on the supercharger side and not worry about the clunky AFM placement. With the throttle body on the intake side...it might even cure the boost spike.
What do you think Greg?
Would moving the throttle body to the intake side of the SC reduce the whine? The whine is loudest at the air filter since it's open to the SC.
People with MAP based EFIs have a huge advantage in this respect. I think you can have the air intake on the supercharger side and not worry about the clunky AFM placement. With the throttle body on the intake side...it might even cure the boost spike.
What do you think Greg?
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Greg Gordon
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Hi JJ,
The curve at full throttle is way rich below 4000 RPM, around 9:1, this really hurts it, I estimate it's knocking off about 20 pounds of torque. However the mixture is about right at high RPM. I will get the graph up on my site soon. I am doing a MAJOR revision to it. We could improve the mixture a little but have not bothered so far.
At part throttle the mixture is only a little rich, so during normal driving it's no big deal.
Hi Zamani. Good questions as always. Putting the throttle body on the intake side is the best way to do it. It would reduce the whine and elminate all boost spikes. However moving the throttle body is not trivial. Those buying the do it yourself kit can do it, but I will never offer that as a part of the kit. Too much risk of someone making a mistake with the linkage and having a disaster.
Actually we have greatly reduced the part throttle whine and eliminated the boost spike issue with a valve from a Porsche 993 Turbo. Think about it, most if not all turbo cars have the throttle body on the discharge side. This has greatly improved the kit, idle speed is now 750 rpm, it's quieter at full throttle, no risk of blown couplers, no uphill on/off supercharger issues, no surge when the supercharger shuts off, it's really about perfect. Quite a bit better then when you and your brother rode in it, and it was pretty good then.
The curve at full throttle is way rich below 4000 RPM, around 9:1, this really hurts it, I estimate it's knocking off about 20 pounds of torque. However the mixture is about right at high RPM. I will get the graph up on my site soon. I am doing a MAJOR revision to it. We could improve the mixture a little but have not bothered so far.
At part throttle the mixture is only a little rich, so during normal driving it's no big deal.
Hi Zamani. Good questions as always. Putting the throttle body on the intake side is the best way to do it. It would reduce the whine and elminate all boost spikes. However moving the throttle body is not trivial. Those buying the do it yourself kit can do it, but I will never offer that as a part of the kit. Too much risk of someone making a mistake with the linkage and having a disaster.
Actually we have greatly reduced the part throttle whine and eliminated the boost spike issue with a valve from a Porsche 993 Turbo. Think about it, most if not all turbo cars have the throttle body on the discharge side. This has greatly improved the kit, idle speed is now 750 rpm, it's quieter at full throttle, no risk of blown couplers, no uphill on/off supercharger issues, no surge when the supercharger shuts off, it's really about perfect. Quite a bit better then when you and your brother rode in it, and it was pretty good then.
Greg, is it possible to cure the rich mixture at low revs by fiddling with the fuel pressure reguator?
I think I read in another topic (can't find it now) that the stock FPR, using the vacum system, is leaning out the mixture as the vacum increases. Is that correct? Or is it the other way around?
Since the mixture follows a linear path (more revs less fuel) and not an erratic up and down path, maybe you can somehow modify/tune the FPR to suit the engine's needs.
Just an idea...
I think I read in another topic (can't find it now) that the stock FPR, using the vacum system, is leaning out the mixture as the vacum increases. Is that correct? Or is it the other way around?
Since the mixture follows a linear path (more revs less fuel) and not an erratic up and down path, maybe you can somehow modify/tune the FPR to suit the engine's needs.
Just an idea...
Petros. Transaxleista!
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Greg Gordon
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Hi Hippo58:
On Stock L-Jetronic the fuel pressure regulator does not really richen or lean the mixture, it just keeps fuel pressure constant by connecting it to manifold pressure on both sides of the diaphram with air pressure on one side and fuel pressure on the other. In other words the regulator sees manifold pressure from the outlet of the injectors and from the vacuum line to the top of the regulator.
Would it be possible to use an adjustabe or rising rate regulator to improve mixture? Yes it would. Will I be doing that? No, I prefer other methods and don't like to mess with fuel pressure.
On Stock L-Jetronic the fuel pressure regulator does not really richen or lean the mixture, it just keeps fuel pressure constant by connecting it to manifold pressure on both sides of the diaphram with air pressure on one side and fuel pressure on the other. In other words the regulator sees manifold pressure from the outlet of the injectors and from the vacuum line to the top of the regulator.
Would it be possible to use an adjustabe or rising rate regulator to improve mixture? Yes it would. Will I be doing that? No, I prefer other methods and don't like to mess with fuel pressure.
hi all, i own an alfa rz with a 3,0 litre V6.i bought the superchargerkit from greg and never satisfied as i am, want to make different piping.does anybody know if the inlet system of the alfa 164 with the chrome pipes is higher than the original milano inlet tract???i don't want it to hit the hood!!
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is there already a mapping available with the gotech for the sc 3,0 engine.
otherwise it maybe is easier to buy this kind of injection.but help from the suplier IS needed!!(mapping) detailing can be done by the professional carshop.
jj when mapping is available please quote me some pricing and details what i need to buy to have everything PERFECT!!
otherwise it maybe is easier to buy this kind of injection.but help from the suplier IS needed!!(mapping) detailing can be done by the professional carshop.
jj when mapping is available please quote me some pricing and details what i need to buy to have everything PERFECT!!
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junglejustice
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- Location: Granolaville, WA