I am thinking about tearing down my running 1.7 that I got with my 1972 914 but have since replced with a 1976 2.0 and refreshing (low dollar) it with new rings and bearings. How likely is it that I will need new cylinders and pistons and crank and cam? I am sure it is a very high mileage engine and had little compression when removed. I am thinking megaquirt for it as well. It had a single carb on it but I have a full set of 1.7 fuel injection stuff for it. Stock compression should be 8.2:1 - is this too high for turbo - without nickies. I guess I might need to get the heads refreshed (low dollar too) as well. Jim

this will probably be no help, but those parts will only need to be replaced if they are too worn and are out of spec. measurement to compare to spec can be performed by a machine shop (or root ). on the other hand, i had the p&c's of my 1.8 which had 60k on it when i got it, cleaned and measured and because they were still usable, honed, and i just put new rings on them and built it back up. so, unless you know the history of your motor (care/maintenance, etc), it's a guess.

That is not to high of compression to run a turbo. but you will have to keep the boost under 6lbs or so.

You can just stick a turbo on it and tune it.. but it wont be the most efficient...
A bigger stroke, smaller piston, (bus pistons would be cheap and low compression fyi) and properly cammed (ask jake, I dono) engine will be Better...

but you wont know exactly what you need to replace till you get in there.

Andrew

Root already volunteered to tear down my 1.7 to inspect the bits this weekend. I'm hoping most is reusable. Guess a megaquirt and an Innovate LM-1 with rpm converter is what I will need once the 1.7 and turbo gets installed into something. I plan to leave my 2.0 car as is. Thanks, Jim

Whatever you do, keep the stock 1.7 cylinders. I would recommend a custom set of JEs, bore the cylinders, match hone, and even maybe surface grind the tops to ensure all cylinders are within .0002" and have the best possible seal. Then if you go with Nickies in the future, you can still use the JEs :-). Do a 90.5 or 91mm bore. If you're so inclined, swap out the head studs too while your at it and maybe even use ceramics in the bottom end, so if a swap was in order, you could leave the bottom end alone then redo the top end. This may seem like overkill, but try to build it as good as possible so that you don't have to do it again. I would even suggest swapping out the rod bolts for ARP bolts if you plan on retaining the stock crank and rods. I would keep the compression ratio to 7.5 or 8:1, kind of like what most guys do on their turbo 930s, although they do have the benefit of aluminum cylinders. The custom pistons would get you the c/r with the optimal .040 deck. You could have the cylinders cryo'ed and the pistons coated, which will help keep the temp down and make everything last longer.

WOW - beautiful stuff on your site - beautiful.

If you ever scrap a cylinder due to a production problem - pls send it to me - I'll put it in my cubical to remind me of why I come to work every day : )

QUOTE (jimkelly @ Nov 4 2005, 10:23 AM)

WOW - beautiful stuff on your site - beautiful. If you ever scrap a cylinder due to a production problem - pls send it to me - I'll put it in my cubical to remind me of why I come to work every day : )

Charles doesn't make mistakes!

charles, your 911 was clean dude....I really liked it. Seemed to run real nice too.


someday i'll have a 911.....


b

It needs paint BAD! I'm replacing the tires though this week, along with the front shocks and outer tie rods. It got kinda wobbly on the way back. Checked out the tires and they are dated 01.77, so the flat spots I can excuse. It just amazes me how well those Michelin XZXs aged!

I can't wait till Jake and I finish my 912, it's going to be wickedly fast and should handle like a 914 (that's my ultimate goal).

QUOTE (cnavarro @ Nov 5 2005, 06:11 PM)

It needs paint BAD! I'm replacing the tires though this week, along with the front shocks and outer tie rods. It got kinda wobbly on the way back. Checked out the tires and they are dated 01.77, so the flat spots I can excuse. It just amazes me how well those Michelin XZXs aged! I can't wait till Jake and I finish my 912, it's going to be wickedly fast and should handle like a 914 (that's my ultimate goal).

i would have to assume that you are loosing the back seat and turning the engine to face the correct way then??

Rich

QUOTE (r_towle @ Nov 5 2005, 06:33 PM)

QUOTE (cnavarro @ Nov 5 2005, 06:11 PM) It needs paint BAD! I'm replacing the tires though this week, along with the front shocks and outer tie rods. It got kinda wobbly on the way back. Checked out the tires and they are dated 01.77, so the flat spots I can excuse. It just amazes me how well those Michelin XZXs aged! I can't wait till Jake and I finish my 912, it's going to be wickedly fast and should handle like a 914 (that's my ultimate goal). i would have to assume that you are loosing the back seat and turning the engine to face the correct way then?? Rich

I've seen one of those. I wish I had the pictures. Aparantly it was an ISMA (I think) mod for a while. The only problem is it involves cutting the roof. Some guys showed me pictures of one they did (and 914 related, the same guys did a /6 conversion from start to finish in one day)

Hyjack over.

LOL, no we're keeping it in the rear, but doing a hot rod 356 engine for it with my 1883cc kit. Keeping it light. It's an early SWB 66, which already handles pretty good in itself. IT also has a few Wevo updates Brad put on there when he set it up back in Sept of last year :-)

Its no run of the mill 616 engine for sure...

Len has about 40 hours of labor just in the heads at this point- It no longer uses 10mm valve stems!

200HP or bust!

I will atempt to answer your question with a question.
What are trying to acomplish?

If you want to wake up a stock 1.7 and get the best bang for the buck possible and end up with around 150 useable HP, then just freshen it up as if you were going to keep it stock. if you find parts that need to be replaced, then consider upgrading those parts. Otherwise keep it stock (and lap the cylinders to the heads). Measure everything, make sure it is all within spec, replace only what is necessary and put it back together.
Spend extra time checking all potential oil leak points. Positive intake manifold pressure tends to increase crankcase pressure a little, so that will make a small oil leak look like a very big one.

If instead you are intent on spending as much money as possible, or would like to end up paying $100 per hp, or have the idea that it makes sense to try and get 250 hp from a turbo type 4 no matter how much it costs (and really beleive you could actually do it for more than a short time), then by all means buy up as many shiny aftermarket parts you can get a hold of. It's your money.

like I tell my VW bug drag race freinds: If you replace every single part on your type 1 engine wih aftermarket, it isn't a type 1 anymore, is it?

And don't forget that camshaft is a HUGE key to the TIV perfomance!