Suggestions Wanted for 2.0 Mods

[BBausser]

I'm going to put some $ and time into getting more umph from my 67 Normale. Starting with a running but long dormant orginal sand cast aluminum stock engine with 47K miles on it. Was thinking of switching to a 3.2 but decided to keep matching numbers. My goals are power, reliability, and low maintenance. Thumbed through Bruce Andersons book and have some ideas but wanted to bounce it off the board. Currently thinking of going to 2.5, crank fired dual plug, PMO's 44's, front oil cooler, better breathing and a E cam. Any ideas from anyone? Keeping the 901 and narrow body. Thanks,

Bill

[kenikh]

Don't bore the case. You can go to 87.5mm bore (Nickies required), with a 66mm stroke you get a short stroke 2.4 on the stock spigot bore. With Mod-S cams and 36mm ports, 10.5:1 CR and twin plugs on carbs, this motor will absolutely scream.

[chris_seven]

I would change the heads to avoid the plug shrouding of the 2.0 litre design.

I think I would use EFI instead of carbs as this will give a better power band and allow better driveability.

I would certainy use short stroke to give power at higher rpm if you plan to stick with 901 transmission as high torque may damage the box.

[304065]

Bill,

The below link currently represents everything I know about 2,0 liter engine modifications.

http://forums.pelicanparts.com/tags.php?tag=901%2F05

Starting with the bottom link, "suggestions for warmed over 901/05"-- you can see I began with the identical thought process. Eventually I came around to ONLY the following modifications:

1) Bore to 81
2) Custom JE 9,5 pistons
3) Dougherty Supercup on 102 lobe center cams
4) Oil bypass mod and piston squirters
5) SC oil pump
6) Updated 930 chain tensioners, idlers & sprockets.

This should be good, with SSI exhaust, for a mild power and torque increase (I'm thinking around 150) and yet has the advantage of being completely original-appearing in all respects.

The big problem with hop-up mods for an early 2,0 is the requirement of increased oil cooling. The factory went to external coolers with the 170HP 1969 911E, that should give you an idea of their view of the limitations of the original loop.

Good luck!

[Mudi]

I agree with kenikh. Don't bore that case... 2.4 with good healthy compression would be really fun..

[jaudette3]

A previous owner made some modifications to the original aluminum case engine in my '67 that I haven't seen anyone else do. The mods were done by a race engine builder by the name of John Bunin of Werkstatt of Vista, California. Modifications included:

o New RS 2.7 pistons and cylinders
o Two 2.7 engines were purchased to find a perfect crank and rods.
o 930 cams
o 40mm Webers built to 42mm - since replaced by 40mm PMOs
o Billet aluminum pressure plate (EBS Stage 1)
0 215mm clutch disc
o Radiator style oil cooler

The engine is fantastic: immediate response, no stumbles, virutally no oil consumption, torque everywhere, still pulling strong at 7100 redline - and bomber reliable. The PO told me that his goal was to build an engine that delivered over 200HP and that would be long lived. It's dyno'd at 220, so that part was accomplished. As to long lived, I'm still working on that. The car has been run hard at Portland International Raceway, Oregon Raceway Park, Infineon and various back-country roads and so far so good.

Cheers,
JohnA

[ajwans]

Cross drill that crank if you're planning on revving it lots. Enlarge
the centre main bearing oiling hole to ensure a good flow of oil into
the cross drilled oiling hole and out onto the centre rod journals.

Use the cam oil line flow restrictors to increase the supply to the
bottom end.

andy

[Will 1967]

Any particular reason why not bore the case? (pretty cheap and more hp for $)

[BBausser]

Thanks for all the suggestions. I'm overwhelmed with all the possibilities that a little 2.0 has to offer. Now the fun begins in deciding what to do, see how my budget will allow what I can do and then get it done. Special thanks to John for the exhaustive play by play on the "Bird". Shooting for being on the road by the end of the month. Will keep you all posted.

Bill

[Flunder]

Why not a Burns Bros distributor instead of crank fire - nice to keep the period-correct look.