Engine number identification in 914-6 GT Tribute

jhynesrockmtn · 01-22-2021, 06:15 AM

I have a 914-6 GT tribute built originally for time trial and autox in CA. The engine was reportedly built by Gary Dielacher's shop. The engine serial number on the fan housing was either ground off or I thought this was maybe a blank case. There is no type number in that area either.

The car had set for many years with reportedly less than 10 hours on the motor. I redid the fuel system, rebuilt the webers, fired it up and it ran great. It's now out of the car to do valve adjust and some other maintenance/inspection.

I did find an engine number near the pressure sender toward the rear. Is this normal?

The engine casting number is 901.101.102.2R.

It has 6 bolt holes on both the upper and lower valve covers.

From other threads I'm assuming this originally was a 1970 S engine? Is that correct?

jpnovak · 01-22-2021, 06:30 AM

That is an original 914-6 magnesium engine case. The serial number is stamped next to the oil breather on a 914-6 - Not by the fan support web.

jhynesrockmtn · 01-22-2021, 06:44 AM

Quote:

Originally Posted by jpnovak

That is an original 914-6 magnesium engine case. The serial number is stamped next to the oil breather on a 914-6 - Not by the fan support web.

Thanks for the information. I had not expected that based on some notes I took when speaking to the person who developed the car. He is a tech at Don Wise's shop in Campbell, CA. I'll try and reach out to him again. He told me the car was built using a factory donor 914-6 but I assumed he was referring to the dash and some other bits as my notes on the engine indicated the last motor he installed was built to 2.4 S spec. from a 911 engine built by GD racing.

Joe Bob · Joe Bob's Garage

They switched engine number locations on 914 installs due to the mid engine configuration.

BTW there is a big difference between 6 installs in the 1970 model year and race model. The 914/2.0 only had 100hp versus the 130 the 911 had that year. The race versions were 2.4-2.7 if I recall.

Joe Bob · Joe Bob's Garage

The VIN# is also different. 914/4 start with 47 then a single digit for the model year. 914 for the original/6. The ignition switch was also on the left.

Matt Monson · 01-22-2021, 06:59 AM

Quote:

Originally Posted by jhynesrockmtn

Thanks for the information. I had not expected that based on some notes I took when speaking to the person who developed the car. He is a tech at Don Wise's shop in Campbell, CA. I'll try and reach out to him again. He told me the car was built using a factory donor 914-6 but I assumed he was referring to the dash and some other bits as my notes on the engine indicated the last motor he installed was built to 2.4 S spec. from a 911 engine built by GD racing.

It was very common to build 2l engines up to 2.4l back then for racing. All it took was a set of P&Cs and some cams and there you go. You probably have a numbers matching car there.

Joe Bob · Joe Bob's Garage

Not to mention counterweighted crankshaft.

jhynesrockmtn · 01-22-2021, 07:52 AM

Quote:

Originally Posted by Matt Monson

It was very common to build 2l engines up to 2.4l back then for racing. All it took was a set of P&Cs and some cams and there you go. You probably have a numbers matching car there.

Thanks everyone. It is a 73 4 cyl chassis. That was clear at the time I bought it. I spoke to the guy who developed the car, along with Don Wise who serviced it for the folks I bought it from. The builder is a tech who works for Don. He explained that he had developed this car through several iterations over the years ending up with this GT tribute with the Jagermeister livery that he ran at autox and time trial events with the Loma Prieta Region PCA. He sourced parts from a factory 6 including the dash, engine mount, trans shifter and some other bits back when they weren't worth big money. My notes had indicated the motor was built up from a 68L case but that could have just been the motor before this one. It's cool it has a factory 914-6 engine actually. I've got a retired Porsche tech helping me with going through the car. It had sat for several years so it was quite satisfying to hear it run for the 1st time.

Joe Bob · Joe Bob's Garage

My 70 conversion. Used a 3.0. Side shifter trans with LSD.

Joe Bob · Joe Bob's Garage

jhynesrockmtn · 01-22-2021, 09:17 AM

Quote:

Originally Posted by Joe Bob

My 70 conversion. Used a 3.0. Side shifter trans with LSD.

I'd love to see some photos, they don't seem to have posted.

This car is a 901 side shifter so I'm assuming it is the transmission from the donor chassis.

Chris Foley is building me his shift linkage kit and I'll be installing a rennshifter. I've driven the car a bit after I got it running and it shifted fine but we'll be looking at the clutch, etc. while the engine and trans are out of the car. The firewall shift rod bushing is shot so that will be replaced with the Tangerine unit.

Knowing it's a 914-6 engine is helpful when ordering parts and for the spec sheet for my race club. I had been searching for 911 engine number information and didn't realize the /6 motors had the stamping where this one is. So helpful!

djpateman · 01-22-2021, 10:04 AM

So the engine is a Euro version type 901/36 from a 70 914/6. Look for the trans serial # on the rib along the bottom of the trans case. Get a photo of it if you can. Just beware of slipping oil from the breather on the top of the case. Most likely it will not have the original gear set, but you would have to tear it apart to find out. That would at least tell you what it was set up for.

jhynesrockmtn · 01-22-2021, 11:17 AM

Quote:

Originally Posted by djpateman

So the engine is a Euro version type 901/36 from a 70 914/6. Look for the trans serial # on the rib along the bottom of the trans case. Get a photo of it if you can. Just beware of slipping oil from the breather on the top of the case. Most likely it will not have the original gear set, but you would have to tear it apart to find out. That would at least tell you what it was set up for.

I'll get that number. It may take a few days. I appreciate the suggestion and the information. I am now curious whether he modified the trans out of the factory 6 to be a side shifter or used the trans from the 4 cylinder car.

Joe Bob · Joe Bob's Garage

The 914:6 had a taller final drive but was still a tail shifter. The number can be dragged off by speed bumps.

Joe Bob · Joe Bob's Garage

jhynesrockmtn · 01-24-2021, 06:28 AM

Quote:

Originally Posted by Joe Bob

Great looking car!

jhynesrockmtn · 01-24-2021, 06:37 AM

Quick update. I ended up connecting with the long time owner of the car yesterday and he was very gracious with taking time to fill in some blanks. He bought the 914-6 case and Dielacher's shop built it up. This was his description;

The case is from a European 914-6. ('70?) I never saw that car. I just bought the case used. The motor mount, steering column and other 914-6 original parts came from my ex-bosses car Ken Mack who used to own Sportech in Campbell CA. The dashboard (metal) was bought new from Porsche. The webers came from Gary's shop. 2.4 S with 2.2 S pistons and S cams. The 2.4 litre and the 2.2 litre are the same bore so mixing the higher compression 2.2 pistons with the 2.4 crankshaft (larger stroke) was a nice combination. Maybe 10.5:1 ?

He confirmed the trans is either the 901 from this chassis or from a 74, stock gearing. Clutch is stock early 911 and new at the time this motor was put in the car.

He had so many combinations of motors in this car over the years my notes were a bit confused and missing some information. He confirmed the motor has very few hours on it. Break in and maybe 2 time trial and autox events.

djpateman · 01-24-2021, 12:36 PM

The transmission # will tell you what base they used. The 914/4 transmission used the widest range of gears from A to ZD. None of the 911 or 914/6 used higher than ZA gear for fifth.