A cheap Fix??

[Eat-um-up]

as ive posted before, i just lost my 2.0 un my 914. My 1.7 that used to be in the car just got old and tired. I should be able to re ring it and be okay. however i have 1.8 heads on a hydrolic 2.0. the 1.7 head i can't get to stop leaking. would i be able to just bolt the 1.8 heads from my 2.0 right on the 1.7? or would the boring out so those heads would fit the hydrolic 2.0 make that not a wise idea?. by the way, the 1.7 has manual lifters

[Dave at Pelican Parts]

The 1.8 and 2.0 heads will slop around on the 1.7 cylinders. The sealing area is too large.

The hydraulic/solid lifter thing isn't really an issue with the heads.

--DD

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Pelican Parts 914 Tech Support

A few pics of my car: http://www.pelicanparts.com/gallery/Dave_Darling

[Eat-um-up]

Originally posted by Dave_Darling:
The 1.8 and 2.0 heads will slop around on the 1.7 cylinders. The sealing area is too large.

so then i would be better off boring out the case and makeing a 2.0 out of it then. What is the diffrence beteesn a 1.8L and a 1.7L anyway? are the crank and cam diffent?

[JP Noonan]

Cases aren't bored out until you get to 105mm pistons and cylinders. All T-4 motors have the same "spigot" hole size. This is the hole the cylinder fits into. 1.7L and 1.8L used identical cranks and rods, the cylinder bore diameter is different (90mm vs.93mm) and the outer cylinder head side sealing area is different (1-2mm difference, not sure). So you 'can' bore out the 1.7L heads to accept either 1.8L or 2.0L pistons, but it is faulse economy to weld and cut 1.8 or 2.0L heads to fit 1.7L cylinders.

Problem is the 1.7L heads have small valves. Best bet is to either stick to a stock 1.7L (80 hp) or rebuild the 2.0L bottom end, use 914 2.0L P/C's (1.8L P/c's won't work with a 2.0L crank because the wrist pin is in the wrong location), and the 1.8L heads (914 2.0L heads would be better, but cost money).

Stay FAR away from 2.0L bus pistons and heads. The pistons are dished, and the heads have smaller valves than the 914 1.7L. A stock 2.0L bus only made 67hp.

P.S.......
\BUY TOM WILSON'S BOOK!!!!!
It tells you everythinh you even wanted to know..



[This message has been edited by JP Noonan (edited 07-28-2001).]

[Eat-um-up]

thanks! I just want to use the 1.7 block becouse the # are all original. but i did fin where i can get rebuilt 2.0w/carbs for $1000. and a 2.4 w/carbs for S1800

[jabez]

Now that we are talking about heads, I am a former Ford racer, who has always believed that engines are just piston type compressors and the larger the valves the more you can compress. I am doing the standard rebuild that you guys seem to like, 1.8 case with 2.0 crank and rods with 96mm pistons. I had the bright idea to put 48mm intake and 38mm exhaust valves into my old 1.8 heads. Any comments, complaints or warnings?

[Dave at Pelican Parts]

The only comment is that you don't want to get the valves too big, or you wind up without enough "meat" around them for good durability. Also, if the edges of the valves (particularly the intake valve) are too close to the cylinder wall, the air flow coming in gets very odd and you can hurt flow over a slightly smaller valve.

I do not know where "too big" is in either of these cases.

Remember that larger valves will help total flow, but will tend to drop the velocity of the air going in. This will tend to be good for high RPM power, and not so good for low RPM torque.

--DD

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Pelican Parts 914 Tech Support

A few pics of my car: http://www.pelicanparts.com/gallery/Dave_Darling

[jabez]

Thanks Dave - speaking of velocity, I have read on this BBS and other Teener publications that if porting is done on a 914 head, that it should not be exactly slick, that a little roughness is better to keep the velocity in check. I believe Brian Yamamoto talked about this in the book "How to Restore the 914". Comments from the "Collective Brain Trust"?

[rmcelroy]

So a reasonable motor-might be 914 case w/2.0 rods/crank, (2.0 96mm bus pistons-to use with 1.8L 914 stock head) and a cam w/duration of 270 and 402 lift?

To produce good low to mid tourqe.

I'll get there Steve.

[Dave at Pelican Parts]

On porting heads: I can see the theory behind leaving the surface rough, but I don't know what the actual practical difference is on a 914 engine.

On Steve's proposed 2.0 motor: The Bus pistons are awfully low compression. 914 pistons would be better. You could probably do even better with custom jobs ($$$$!!!!) if you knew more about how these motors worked than I do.

--DD

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Pelican Parts 914 Tech Support

A few pics of my car: http://www.pelicanparts.com/gallery/Dave_Darling

[DDS]

On porting:

I was told, intake rough to better mix fuel/air and exhaust smooooooth to help it get gone.

Is Jake Raby still around? He'll know for sure.

[jabez]

Steve - on the 96mm cylinders and pistons, since our buddies at PP didn't have them, I had to go to my next best supplier, European Motorsports. The fin castings on the cylinders are nice and clean, and the flat top pistons are VERY nice. They also supplied EMPI shims for the cylinder deck height as well as rings and wrist pins (less clips).

[Conrad W Peden]

I havent seen it mentioned but..

The cranks between a 2.0 and 1.7 are different. The 1.7 is 66mm stroke and the 2.0 is 71mm stroke.

So if you dont already know, a 1.7 crank will not work with 2.0 pistons and cyls.

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CWP/VIR
72 914 L20E in rusto.
73 914 L20E 2.0L in resto.
http://members.rennlist.com/a914lover

[This message has been edited by Conrad W Peden (edited 07-30-2001).]