2.5L Twin Plug Rebuild Options

[CaryPhotography]

Hey Guys,

I'm new to the Pelican Parts forum and after seeing all sorts of great information I decided to join in to get solid information, bounce some ideas around, and get some help.


Down to business. The project I'm starting to work on is a 1970 911T which already has a fiberglass wide body kit, various performance upgrades, rear tires are a 285/40 15", and more importantly a 2.5L twin plug 13:1 compression motor with weber 40's. I also have the Bosch mechanical fuel injection system for the motor. Some 20 years ago, the motor was built by Wayne Baker of "Personalized Auto Haus" in San Diego. The motor has been seating for over 15 years either in a garage or in a storage unit and when I checked the other day, I could turn the fly wheel over by hand and oil (not water) poured out from one of the ports as I leaned the engine over. From what I'm told, that's half the battle.

The motor was pulled from the car because both work needed to be completed and the motor needed to be rebuilt. From what I'm told, this is a race motor that was detuned for street use, meaning rebuilds are generally done due to hours of use and not miles of use. The motor was functioning when it was pulled, just needed a rebuild to freshen it up.

Unfortunately, my budget is tight, VERY tight which seems dumb because tight budgets and Porsches do not go hand in hand. As much as i want to rebuild this engine back to it's original glory, my check book simply can't hand that kind of stress. The big question is: Is there a way to freshen up this motor without doing a full rebuild? Could it be as simple as replacing main bearings, seals, and pistons rings in order to get this beast running again? I don't want to but I may be forced to, put the Bosch mechanical fuel injection system up for sale in order to afford a rebuild.

The other idea I've had, sell the motor with the fuel injection system and purchase a stock 3.0L so I can get the project going sooner but I really do not want to lose these twin plug heads.

This may seem like a stupid question but... Has anyone driven a twin plug engine and how would it compare to a stock 3.0L?

[Flieger]

I am glad to see you took my suggestion (on Pelican) to join this board. Welcome.

[ibmiked]

Hi Cary,

You make no mention of numbers matching or not. Based on the apparent mountain of other work you have ahead of you, I would definitely go and find a 3.0L. In the end it will be a known quantity. Once you open that 2.5L it's worth very little until it is put back together and that could be a bill you are not prepared for. That's the kind of thing that can stall a project for years.

Good luck whatever you decide,
Mike

[Frank Beck]

First of all, was anyone hurt when the earthquake hit that garage?

2.5's and tight budgets don't mix. As a matter of fact, 911's and tight budgets are like oil and water.
Just curious what kind of $$ you are factoring in for a rebuild? Are you absolutely, positively sure it's a 2.5? If it's a race motor, forget driving it on the street; the need for race fuel and undrivability of the cams will make life miserable for you.
Call Wayne, he can probably help more than anyone regarding info about the motor. He's a great guy.

Good luck with the project!

[Bill Simmeth]

With the twin plug ignition, MFI and the hand of Wayne Baker once upon it, even condition unsure, you should be able to sell the 2.5L and wind up with a chunk towards a running 3.0L - IMO a much better route for a low-budget DIY car. And low budget 911s are still doable if you're mechanically inclined, willing to get dirty and have thick skin so you're not bothered by the peanut gallery staring down their noses at you. Plenty of people willing to help guide you here and on Pelican. Good luck with the project!

[geneulm]

When I was in college in the early 80s in San Diego, Wayne Baker was our local super-hero -- taking on the big factory IMSA teams and winning. He had a featherweight shrunken tube-frame GTU 914-4 that was insane (at least we thought so). Beat the factory Mazdas on occasion. Then he won Sebring with a well used 935 that he turned into a 934. Gave us all hope when running our new-parts-from-the-junkyard cars at the stadium autocrosses.

That engine is living history. Bone up, ask questions, take your time and fix it!

[Flieger]

Wow, I just noticed you are in Thousand Oaks. Small world.

The motor is very cool, but won't be drivable on the street with that compression ratio. It needs a rebuild anyway so if it was rebuilt with less compression and the MFI then it could be a really fun motor. But that will cost more.

The cheaper route is the 3.0 but you loose all that cool factor.

I know for me my car is just a weekend toy. Driven very little. And it had been off the road for ten years or more in various shops due mostly to lack of budget. But now it is back and most of the way to where I want it. But it will never be finished.

For me the work in progress project aspect is almost as fun as driving. But then I am a mechanical engineering student.

We will have to meet up sometime. I'm headed back to San Luis Obispo this Friday but I'll be in town for a couple more days, and usually come home for the weekend every couple of weeks.

[CaryPhotography]

Hey guys, thanks for all the great feedback.

The truth is, I'm fully aware of the tremendous amount of work I have ahead of me and I'm looking forward to it. I grew up watching my father racing various PCA events down in San Diego and hot laps through the santa monica mountains. Those memories are fueling the rebuild of this 911. The motor was built for racing by Wayne Baker and for a period of time it was posted up in his shop as a backup engine. From time to time my father made mention about it to Wayne and eventually ended up in the car you see now. The car was running when he decided to start having body work done to it and up until that point there had been quite a bit of work already done to the car in the form of performance upgrades. 15 years of seating doesn't exactly help all those seals and hoses.

I'm very hands on when it comes to my own vehicles, simply because I grew up around it (thanks dad). The garage it stocked will all sorts of tools and supplies to help aid the progression of this project. I'm fully aware that it's not going to be fixed over night and I've got at least a years worth of work ahead of me.Over the past decade I've worked in the bicycle industry as a mechanic, tech, warranty supervisor, and shop manager. I know this is different, but the underlining trend here is, I'm hands on and I like to think I'm fairly mechanically inclined. I even studied Industrial Technology at Humboldt State and Cal State LA.

Yes, the garage isn't exactly a model for organization but at the angle the picture was taken isn't exactly helping the cause. Within the past 7 years, we've switched over to building a jeep for rock crawling so a lot of the parts you see lying around are for the jeep, not the 911.


As far as numbers go... That's really of any concern because I have no intentions of selling the car. My father is the original owner and I plan on building it back up with his help so it stays in the family. We don't have the orignal motor (father blew it up), nor the original wheels, fenders, and various other parts. The end goal for this car is a street legal track car with a minimalist interior, rough looks, and a appetite for the road.

[CaryPhotography]

Wow, I just noticed you are in Thousand Oaks. Small world.

The motor is very cool, but won't be drivable on the street with that compression ratio. It needs a rebuild anyway so if it was rebuilt with less compression and the MFI then it could be a really fun motor. But that will cost more.

The cheaper route is the 3.0 but you loose all that cool factor.

I know for me my car is just a weekend toy. Driven very little. And it had been off the road for ten years or more in various shops due mostly to lack of budget. But now it is back and most of the way to where I want it. But it will never be finished.

For me the work in progress project aspect is almost as fun as driving. But then I am a mechanical engineering student.

We will have to meet up sometime. I'm headed back to San Luis Obispo this Friday but I'll be in town for a couple more days, and usually come home for the weekend every couple of weeks.

What part of Thousand Oaks are you in? I'm over by Westlake Blvd and Decker Canyon. I'd be down for meeting up if you'd like.

[Flieger]

The very end of Moorpark Road, south of the 101. My Dad and I are taking the 911 out for a drive tomorrow afternoon if you would be around then.