DonT

Let's get right to the meat of the subject ---


FYI ---

1987 Porsche 928 S4
automatic transmission
70,400 miles
only mods -
Tim Murphy Supercharger Kit
RMB

The 'before run' had a spike
The spike was removed from 1 of the printed outputs
The SC runs were made with 7 pounds of boost
ALL dyno runs were made in 3rd

----------------------------------------------



The 'before' & 'after' compairson

DonT

Am I happy?

You bet your A$$

jorj7

Don,

Looks good. Only 7 psi boost at the dyno, was there any
problems?

I want to get mine on the dyno again when I get the boost
up to 8 psi. This weekend I'm taking off the s/c and i/c so
I can smog the car, then next weekend I'm planning on
putting on a new belt (thanks Tim). My before runs are
similar to yours (251-263 hp on 2 different dynos on 3 different
days).

DonT

George -

No problems. I made an adjustment before the dyno run and didn't retension the SC belt enough.

The guys at the speed shop couldn't believe the HP increase!!!! Also, lots of compliments on the SC install.

I'm waiting to see your results.

Lagavulin

Excellent; welcome to the MURF928 32v SuperShark Club!

How are you liking all the extra power? (..stupid question, I know)

atb

Don,

Did you not have the kick down disconnected? Where's the first half of the graph?

Normy

AWESOME!

-It occurs to me that all or almost all of the Murphinzed 928's are black...

N!

Old & New

Errr...

*Almost*

mspiegle

Looks pretty clean and good power increase. Is that your filter sucking in hot air? Maybe more power can be had...

DonT

and I thought the 928 was fast before. It's great having all the horses 'underfoot'.

Thanks for the welcome...

SharkSkin

Don, the upper parts of those charts look great. What do you suppose accounts for the Yugo-like power at <3600RPM?

slate blue

I was thinking the reason the early s4 does so well supercharged is that it has lower compression than the late models. From 1990 on. The comp ratio was increased similar for the GT. Early cars have 9.4 versus 10 for the late cars and the GT.

DonT

You're right - I didn't have the kick down disconnected - because I didn't know (and apparently the dyno operator didn't know either) that it should be disconnected.

Here's what the graph looked like when (I guess that's what happened) the kick down switch activated.

DonT

I also have a dyno run (made on a Mustang Dyno) from the last Frenzy in Northern Virginia. I strongly considered using that run versus the run with the spike. I didn't want to mix runs from different dyno manufacturers - Mustang & DynoJet.

The Mustang dyno run is included for your viewing pleasure.

John Krawczyk

Too cool. Now you need some Big Reds. (so i can buy your S4's).