Date: 11-Sep-99 11:10 AM
Author: ephemeris
Subject: Experience with Endyn modified blower: Part 2

Okay, just keep in mind that this is preliminary...

I'm one of the people who sent Endyn (i.e. T.O.O & Nitro & co.) my Eaton / Jackson Racing supercharger for rework. When I reinstalled it, using my original 3.4 inch blower pulley, my boost at redline went from 7.5 to 9.5 PSI. An amazing gain of two PSI !

T.O.O's been on me to switch to the 3.0 inch blower pulley he supplied. I did it earlier this week and here's where I am currently:

Please note, I switched to 310 cc/minute injectors. Previously these had idled terribly for me, but that was when I was using a simple resistor in series with the TA sensor. I replaced that with pressure actuated switches (supplied by Endyn) that add resistance to the TA sensor only as boost comes on. Idle became pretty smooth albeit somewhat rich with these switches and the big injectors. So I converted the Honda fuel pressure regulator to an adjustable one and dropped my non-boosted fuel pressure by about 6 PSI. My idle is now very nice! A BIG improvement!

As to what you really want to know, I'm getting a solid 10 PSI of boost at 4000 RPMs and about 13 PSI at redline. The system is not intercooled and I run pump gas. Is this plausible? I have depended on the J&S SafeGuard knock/retard unit to protect the motor during my trials and tribulations with the blower over the last three years. This J&S is real important since the engine is definitely more knock prone than it was with the larger pulley (DUH! Physics works!) In particular, the engine has a fairly strong tendency to knock at WOT from about 3500 to 4500 RPM. On the other hand, Above 4500 RPM, it's often possible to accelerate to redline (6500) with no knocking! Since the D16's volumetric efficiency peaks somewhere in the 3500-4500 range, it's no surprise that that's where it knocks hardest since it will tend to lean out there.

Is the work Endyn did for me a "Good Thing"? Well...right now I can't wipe a silly grin off my face. On the other hand, it's not for everyone. It's definitely NOT for someone who uses pump gas and refuses to spring for the J&S knock retard unit. Let's face it, it's a miracle I can run this hard without an intercooler. But it requires some cash outlay and some use of common sense. If I tried to climb a long grade in 5th gear at 3500 RPMs while boosting without some sort of knock control...BOOM! And as always some self control is required when operating on the edge. Nonetheless, it looks pretty good to me :-)

About the car:

1991 CRX si with about 80,000 miles on it JR/Eaton/Endyn blower running 10-13 psi 3.0 inch diameter Endyn blower pulley Endyn/Thompson induction tube with K&N filter Bored throttle body from Russ Collins 1992 Honda Civic crank pulley/harmonic balancer Kamikazee exhaust manifold RS*R stainless cat back exhaust Upgraded fuel pump (Walbro via JR) 310 cc/minute RC/Lucas injectors Honda fixed fuel regulator made adjustable by B&M CommandFlo 93 Octane Amoco gasoline (no octane booster) MSD 6BTM boost retard ignition unit set to about 1 degree/psiJ&S SafeGuard knock retard unit Autometer boost and fuel pressure gauges K&N Air fuel ratio monitor (soon to be replaced with an Autometer one) Stock bottom end Quaiffe LSD CRX DX final reduction gear (a little less quick, a little better mileage) No stickers ;-)

Date: 12-Sep-99 03:57 PM
Author: ephemeris
Subject: And one more thing...

Let me be clear about this. The pull from 4500 to redline is amazing. It pushes me back in the seat and I stay there until my foot relents. It's pretty scary (in a fun way;-)

Once again my thanks to Endyn!