Sboxin

Well, it is done --- for now anyway -- off to the track at Chuckwalla ,CA Nov. 30 -- looking forward to it!!

We have finished with the 1992 964 engine rebuild and installation into my Son's 1978 911 SC race car.

The following Pelican Engine build thread has the photos and end result Dyno graphs.

http://forums.pelicanparts.com/911-e...pproach-2.html


The 964 engine has so far proven to be a very good engine.
We towed the car to California to Sergio Nardi's shop - Game-Face Motorsports in La Habra
-- where Steve Wong worked for 5 hours on the Dyno Tune (we had an issue with the throttle cable
adjusting nut coming loose and changing the WOT switch activation).
Steve spends a lot of time smoothing the A/F ratio -- there were 28 Dyno runs total.

The bottom line is 270 RWHP and 250+ RWT with JE 102MM 12.5 CR pistons,
Webcams 20/21 cams, custom headers and stock 964 intake.

Don Jackson Enterprises in Phoenix is the engine builder and conversion
into the 1978 911 SC race car (we took out a perfectly good 3.2L engine).
Thanks to engine builder Roland for his efforts and patience with this Dad always asking
questions to learn as much as I can about Porsche engines/cars (never too
old to learn something new). DJ Jackson provided the primary Porsche technical guidance
thru this whole project and coordinated the many details
it takes to complete a project like this --- A BIG Thanks DJ !!!

Thanks to EBS in Reno for their technical help on the pistons and reconditioned cylinders.

Thanks to Steve W and all of you for your input and help!!

This process takes a lot of patience ......

Regards,

Sboxin

Well.........latest report on engine after running hard at weekend track event

Two things:

1) When the valve rocker arms were removed for oil leak sealing pitting was found;
they need to be reconditioned
Note: this was about the only part not refreshed or replaced

2) We need more cooling (as several had mentioned earlier- we were just waiting
to see how much more we needed) as temps went to 250F when engine was pressed
to 7K RPM during race conditions - it would cool back to 210F when shifting at 6200.
Two front fender coolers will be added to the 26" front center cooler.

My son is happy with the new engine and the increase in power...
Photo at Chuckwalla Valley Raceway - Desert Center, CA (middle of nowhere - but great track)

Regards,

Sboxin

Well . . .

When you put a more powerful engine (270RWHP-255RWT) into your Porsche with a 915 gearbox
the next thing you need to do is rebuild the gearbox - - we broke a pinion gear
tooth and wedged it into the 5/R gear change lever - - that's better than catching
in a gear set. So we dropped the engine/trans and took the trans to CMS in Lake
Havasu, AZ for a really good rebuild with many new parts - it has been 3 years
since the last rebuild - it was due - they did an excellent job. We also added a trans
cooler with pump and filter (work done by Kent Porter shop - Precision- in Gilbert, AZ). Also, pics
of the inside the car with the cooler located behind the driver seat on the shelf, NACA duct and hose in the quarter window.

Steve Weiner Rennsport Systems was absolutely right about adding more engine cooling
-- the added 2 Carrera fender
oil coolers needed more air flow in our warm May and June temps. So, we opened
the headlight buckets, expanded the turn signal openings and added aluminum
panels to act as air ducts through the oil coolers (copied idea from others on the
forums -- air flow is really important)
Thanks to the Don Jackson shop in Phoenix and Roland for mounting and plumbing the coolers - -
we also changed the front center cooler to a Setrab oil cooler from Elephant Racing.
The 911 headlight rock guards make for a nice touch too.

The results are that the trans now works perfect and the engine used in race
conditions and 100F air temp runs at 210F. I am hoping this is the "end of the story".
Oh, and my son scored 4 more Hoosier R6 race tires in 2 events. The NASA
organization changed the classing during our 964 engine build - so we just
bumped the horsepower and weight up to reach the top of the class - ST3/TT3.

Thanks to all who post on this and other Porsche forums for valuable
information and experiences.

Cross reference to Pelican post:
http://forums.pelicanparts.com/911-e...-approach.html

Regards,

Matt Romanowski

You should think about measuring trans temps, especially if you have a LSD. You would be very surprised at how hot it can run. You might want a fan inline with the air hoses for the cooler.

Sboxin

Matt,

Thanks . . .

We are learning about how to manage the bigger hotter engine and more power . . .

We have a transmission temp sensor incorporated into the bottom
CMS shift lever cover plate in the first photo where you can see the white wire.
A dash gauge provides the temps for turning on or off the manual cooler pump switch.
For 2 track days - May and June - the temps stayed at 180F - used the
pump/cooler in May but not needed in June - difference was actual on track
time and very different track layouts - May = race on long hilly 4000'
elevation -- June = short track @ 800' elev. 20 minute time trials.
We only run one long race a year - either 1 or 3 hour, but we will be watching the oil and trans temps very closely.

We did learn that race transmissions absolutely need a periodic rebuild - -
CMS did an excellent job rebuilding this 915 gearbox - Thanks to Shawn.
The GT diff was rebuilt and what a difference that makes too. They replaced the diff side plate with a CMS machined product that incorporated the Turbo
diff larger bearing also. We might be good to go for another 2 years . . . and
maybe longer because of our reduced track schedule this year and next.

Regards,

Photo of June track day in Phoenix early morning - done by 10AM . . .

Matt Romanowski

I missed to wire for the sender. Logging our trans temps (901 behind a stock 3 liter) it's very surprising how hot things can get. We run a cooler with a fan on it and with that setup, we're staying around 225F.

Sboxin

IMHO the trans stays cooler if it is in front of the engine = 911
rather than behind = 914 , Boxster

Our friend with a track 914-6 ran a trans cooler in the rear with a fan on all
the time - worked fine - but had a lot of heat from engine and exhaust.

Regards,

Matt Romanowski

It gets hot back there, but not that bad. Air temps from the rear trunk area on a lap at NHMS.