Perfect Engine Configuration

It's been a while since I've been here but I've been very, very busy. As some of you are aware, I am a mechanical engineer during the day and a VW enthusiast during my non-work hours. Last year, I tinkered with several engines and found that the best strategy for our lightweight cars is to mimic the mechanical characteristics of the 356/912 Porsche engines while taking into consideration many other engine and performance variables.

During 2007, I built a few engines for some fellow locals and ended up with some very, very pleasant engine configurations. One individual had a stockish Type 1 1914-cc engine as it came from the replica supplier. I basically put in another cam, increased the compression, dynamically balanced all parts, redid the heads with bigger valves and had them ported and polished, and then redid the exhaust. The difference was night and day! I also did another engine using the same stroke and bore as my 912 and with a little headwork, got an even better engine. I was so happy with this last one that I am currently building one for my Speedster. Basically one can get a very nice performing "budget minded" engine under 2 Liters while keeping reliability in check. There are a lot of many other things I did but it would take a lot more delineation......

I also have a Type 4 configuration I am building that my buddy is trying to persuade met to sell to him....probably would, but this one will get my set of ceramic lifters so I most likely will keep it for later. Again, this engine is actually only a 66-mm stroke but I am doing some other things to keep in line with my strategy.

Heck, I gotta keep myself busy so I do not have time to think about other things I should not be thinking of! LOL

Tony...

Sounds like you have been busy! Full speed ahead with your projects...and keep us posted with some pics!

The 356/912 engine had 83mm pistons and a 74mm stroke for a total of 1,601 cc's. The biggest advantage that the Porsche engine had was it's heads. (and a 3 piece engine case)

VW heads can be made to flow better than Porsche heads but will never have the same exhaust note as the Porsche heads had rectangular exhaust ports.

I built a VW engine for a Baja Bug that I owned about 30+ years ago by using stock VW 85.5mm pistons and adding a 74mm crank (up from a stock 69mm crank) along with a cam, ported and polished heads, oversize valves etc etc. This increased the engine displacement from 1,584cc's to 1,699cc's. It was a very healthy engine. Another great combination that I built had 92mm pistons and a 74mm crank for a total of 1,968cc's. That too was a great engine and like the other, lasted like an Energizer Bunny.

Great info guys! Wow Larry; that's surprising after all the bad rap the 92's get.....

Tony thats very intersting i still have 2 914s here and i like to here your more detailed build plain Some time whe you can please jot it down step by step. Mod by mod. I'd be in your deat.

The thing I've been trying to do is not only replicate the displacement configuration, but also do it as economically as possible. I had a 2110-cc (with a 911 fan shroud that I designed and fabricated myself...see my pics) that I built and it was way just too scary strong in such a light vehicle and felt more like a drag rocket than a road car. Given that I also have a 1965 912 and a 1965 356 SC, I've gotten used to the Porsche feel of the pre 70's Porsches. I do love the way these two cars drive and am trying to get the same feel with my replica and I am just about there. With the 74-mm x 85.5 engine, I was able to do this along with the other mods. I want to configure another similar engine but I will once another of my buds steps up to it since I am already almost done with my engine. I am paying special attention to not only the mechanicals, but also the induction and exhaust. I am even considering designing an exhaust like the 356 or modifying one for a Type 1. The 356 mufflers do flow nicely and perform well for a stockish displacement and doing this, would not only allow a fitting system, but not hold the engine's capabilities up. I do know there are a lot of Speedsters out there with that stockish 1914-cc engine that is not well configured. Basically, they've gotten a crate engine that was refitted with 94-mm pistons and cylinders but no carburetion, exhaust, cam change or headwork to complement the bore increase.

Hey, are there any Vegas locals here that want to safely experiment with their engine? LOL

By the way, I do have my 911 fan shroud with custom oil cooler setup that I am considering selling. See my pics in the phot section (LVWOODGOD)....it worked very well and I was able, through actual engineering, to balance the cooling very well. I drove my car in the super hot Las Vegas climate and had no problems.

I'll post more later when I get a chance.....

I have chance to buy a running 912 engine . Would you get it or leave it

$1100 if I have not been fibbed to. I was made aware of it this morning. A freinds dad wants to sell it to clean out his shop..

The 912 engine stock is a great 105 HP and it can be increased with 86-mm pistons. The condition of the engine determines the price but at $1100, it is still a bargain if complete and as a core (at least).

I concur, 1100 is a good price. Is it a complete engine (distributor, carb's, linkage, flywheel???)

If it has Solex carbs, they probably need to be machined and new throttle bushings added but a pair of webers can also be used.

Just be aware that a rebuild on a 912 will easily cost $5K plus. That's what I spent in 1992 and I did most of the work myself. I had Harry Pellows do some balancing work on the flywheel/cluch and a shop did the valve job but I did the rest.

Too bad Harry is gone. He was quite a unique person, full of himself but when it came to Porsche 356/912 engines HE WAS THE MAN.....

13mm across the flats.... If you've read any of his articles, that's how he describes which wrench to use on a specific bolt

Assuming all of the internals are still within spec, the costs should be minimized. Bearings are usually the major cost but having to replace damaged or compromised parts, can be costly. 912/356 engine rebuild costs can greatly vary because of this.... Also, the aftermarket is very limited for these but there are more and more parts being made available although some are unproven but time will be their judge.

Tony, I had a very healthy 2110 in my 84IM, and I didn't think it was overpowered. Mind you, I now drive a V8 powered Mazda Miata :-)

Ron - have the best of both worlds and put the IM body on your monster Miata!!

Actually CIP has the big bore piston/cylinder set for 356/912 engines on sale; price is not bad.

Heck, with the back of my IM gone there's plenty of room for a V8 :-)

i dont know why but the price has come down to $300 >Id bet its a hotter than a smoking gun.

I did find out carbs are gone one valve cover missing and I'd bet its locked up. But its hard to say but of a core that wld be a sweet price

Barry, where is it located?