Installing 6 cylinder engine

I have decided to pull the trigger and install a 911 engine in my speedster. When I was home last weekend, I took some measurements on the engines that my dad has laying around, it looks like it will fit in my FiberFab kit. Of course, I only measured the depth of the engine (the extra length that 2 cylinders add), and I didn't think to measure the height differences. I'm probably going to get a 3.0L.

I've seen pics of various size 911 engines in IM's, but has anyone done this in a pan-based speedster? Are there modifications that need to be made (i.e. fan shroud)? Please let me know.

Also, don't try to talk me out of this. Like my future wife, I know the engine will be expensive to maintain, and will add extra weight.

Yes, it can be done but plan on a lot of fabrication.

Are we to assume that you'll be installing a new transaxle to take the power that will be delivered by a 3.0 engine? If not, I'd re-think the project. If so, plan on the cost of a new transaxle and favrication of mounts, new engine mounts, total re-do of the rear suspension to accomodate the IRS, wiring, return line for the gas tank, and load of other things that will pop up when you start the project.

A 'real' smart man would build a Type IV with a DTM shroud.

I believe the 911 engine is also heavier, so your weight distribution would be worse, making the car a handfull in the curves. I believe IM resolves that by moving the whole shebang forward a couple of inches.

Adam, there are two likely points of interference on your car (that I can think of off-hand besides those mentioned above). The cooling fan assembly may hit your deck lid. That's probably your most likely contact area. The further you can put the engine toward the passenger compartment, the better this fit issue will be.

The CIS system is fairly tall and will require a return line. Line is not a big deal, but the airbox and plenum are tall. Check that too. Or go with carbs. On the 3.0 you can use 40mm webers, 40mm PMO's or even Zeniths. Don't knock the Zeniths, they are cheap because everyone thinks the webers are hugely better, but for street driving the zenith is arguably a better carb. Budget $600-$1000 for used webers, $200-$300 for used Zeniths (good condition). Use short stock manifolds or the PMO "short" manifolds.

The 3.0 engine ignition system will not trigger most tachs. Budget for that. Either a 3.0 tach or signal amplifier or have your tach redone and obviously calibrated for the six.

The 915 transmission is HUGE compared to a VW. The 901 transmission, though far less robust is somewhat smaller than the 915 and is capable of decent life behind a 3.0 as long as you don't act like a taco-brain in 1st gear. 1st gear is unsupported in a 901 transmission.

I've never seen a 911 engine in a pan based speedster. But I have seen 911 engines in VW bugs so obviously it "can" be done. By "can" I mean with skill, craftsmanship and money.

As far as maintenance goes, the older CIS systems can be somewhat troublesome to repair. They run great, and then drive people nuts when something goes wrong. Usually, people find vacuum leaks and fix them or just start swapping parts (like Warm Up Regulator) until they get it fixed. Yuck. If yours has problems, I would highly recommend swapping to carbs. The throttle response is significantly better and the troubleshooting is pretty breezy.

Also, check the headstuds (especially the lower ones closest to the flywheel) on the 3.0. You don't want to go thru this very difficult build only to find you have broken headstuds and need to rebuild the engine.

*also* budget for brake and suspension upgrades. Never hot-rod a car without doing that first.

angela

Now THAT'S what I'm talking about. Thanks, Angela. I've seen the swap into a Vanagon, but couldn't find any info on the Internet of people putting them in Beetles. Good to know it can be done.

Just my opinion------You must have your own personal and powerful reasons for wanting to do this. I "assume" that since you are not scared off by the issues involved/mentioned you must be very capable mechanically(and the fact that your Dad has these engines laying around, I'm sure you have experience to draw from).If I were looking to do this kind of upgrade I think I would trash the pan and go tubular to your specs and not try to make something else work(read;patch together). There is a person on "thesamba" that makes a tubular chassis that fit pan situations (if I remember it was somewhere between $850-$1200)that would make your life quite a bit easier. Much easier to add extar engine supports to a tube frame.
Pan based speedsters frame work in the rear is for body support not torque.Good luck with your project!!

He is in Fresno, CA but I think he is a little guy woulf could do your adaption and then slide them together as a package.
Looky here;
http://www.thesamba.com/vw/classifieds/detail.php?id=291681

Adam: You will likely have to add some reinforcement to the pan so at the same time consider using 911 suspension and brakes. It will make the car much more enjoyable to drive and give it a higher resale.

Heres an article on putting the 901 into a VW beetle. As you can see, even with a 4 cylinder engine, that car needed cutting and welding. But the point its, it has been done. Putting the six in is the next part of your adventure. By the way, the 901 is also much lighter than the 915.

http://www.aircooled.net/gnrlsite/resource/articles/porsche5spdconv.htm

Also, Kennedy Engineered Products (KEP) has a 901 to 3.0 conversion flywheel and clutch. Straight off the shelf and pretty affordable. Works with no problems. You can pull a 901 from an early 914. Later 914's were side shifters, stay away from them. The 901 also, obviously, came in early 911's. But you can often pick up the rear shifting 901 from a 914 pretty darn cheap. The ring and pinion flips easily for your rear engined application.

That chassis fab suggestion above could be REAL sweet!

Now lets talk about lopping some weight off the assend of your car. Make sure your battery is in the front as far forward as possible. Lighten everything you can in the back. Lose the A/C and the CIS if possible. Go with a high-torque starter (they weigh like 7 or 8 lbs less than the 911 starter). Think light. Push the engine/transmission as far forward as possible within your axle configuration. The CV's you choose will effect how much angulation you can put into the axle. Type 1 CV's only like a few degrees. We have type 1 cv's in our 911 spyder, but very little angle to the axle. 11,000 miles, so far so good. But the 930 CV's allow a huge amount of angle. Every quarter inch counts. Even if that means cutting a big old fatty hump into your floor pan for the tailshaft. Make it so!

Also got to fab up the dry sump system. Another suggestion: In 1972 Porsche put the oil tank AHEAD of the rear axle. You filled the car's oil from the right side. Do one step better. Put the oil tank in the FRONT of the car. You are going to have a couple of gallons of oil up there and the weight of the tank. This should help your weight distribution. The 3.0 oil pump will have no issue with this configuration. Use big lines, -12 minimum. Don't put the wrong size fittings on the custom tank like we did and have to redo them (DOH!)

angela

I already have a 901 tranny installed, so that part is taken care of. I would probably do the brake and suspension upgrade before the engine. There has been a dearth of 911 engines (and Porsche engines in general) on the Internet in recent months, and prices have gone way up, so I'll hold off until they come back down. Or, I'll just talk my dad into selling me an engine instead of putting it on eBay.

Would a standard rear disc conversion be okay, or would I have to go with the full "big brake" upgrade? I'm sure it really depends on how I'm driving the car. I'm much less concerned about the work required to do the brake upgrade than the suspension. I'm pretty much clueless as to what should be done for the suspension. It's an IRS setup now (via 1969?).

Adam,

I have a CMC (same as the Fiberfab) with a 911 6-cyl and 901 trans. The engine is just the 2.0L, but it

AWESOME Robert!!! We have a saying in our shade-tree garage "couple a beers and a sawzall, it'll fit"!!! More pics Robert, that car is really cool and an MFI 2.0 is a neat engine (and very very light).

Did you know that your engine weighs just 12 pounds more than the 4-cam four cylinder used in the spyder and the carrera 356?

angela

How about checking out the extra two inches (or so) of extra length that you need to get the driveshaft in and out of the flywheel? Engine length might fit once it is installed, but can you "get it in"?

That's not a bad idea, if you can make the room. On a 911, you remove the engine and transmission together. Makes for real interesting conversations when you realize you've slid the clutch fork BETWEEN the throwout bearing and the pressure plate instead of into the bearing...

You only discover this after you put the axles in, the oil tubes on, wiring etc.... Go ahead, ask me how I know this...

angela

Why don't you just go turbo? Have you priced a valve job on that motor? How about clutches and tune ups?

I know this sounds ridiculous, but I think a 6 cylinder would be easier to fit than a turbo... I only form that opinion based on turbo kits that I've seen on beetles where the rear deck needs to be removed. do they make a kit that would fit in a speedster?

plus, i think i'd need to "beef up" the vw engine before i did that.

...and the sweet sound that little six will make will be music to your ears. I'm sorry, but a turbo VW just does not make the same sounds. The little 911 six wound right up sounds like a sports car should..IMHO. VW's usually sound like a beetle...not that that's a bad thing. I guess it comes down to what you like

This is a bit off topic but anyone know the differences between 901 transaxles? My car has a 901 in it but 1st gear synchro is gone. I have another 5 sp 901 trans but this one was a factory option on my old 912. The 912 transaxle is out, cleaned up and polished. I was thinking of putting the new synchros in it then replacing the 901 in the car with this 912 901 but what are the differences in gears and would it be suitable? Both are stock from what I can tell...

Brian

Brian - hope you can read these. They are the charts for all the years and all the gears of 901 in 911 and 912.
angela