Thoughts on some different engine configurations

[Danimal16]

Can a 2.5 liter short stroke be built with a later 3.0 or 3.2 liter aluminum case?
From reading the thread this would be the 66 mm counter weighted crank with the early 2.0 rods.

[kenikh]

Originally Posted by Danimal16

Can a 2.5 liter short stroke be built with a later 3.0 or 3.2 liter aluminum case?
From reading the thread this would be the 66 mm counter weighted crank with the early 2.0 rods.

This is only possible with the custom crank built by Supertec; the OEM 66mm crank will not work. The early crank will not fit the later case.

[Danimal16]

Originally Posted by kenikh

This is only possible with the custom crank built by Supertec; the OEM 66mm crank will not work. The early crank will not fit the later case.

Thanks. I am learning about all of this. Is there a quick engine built on the 7R case. The search for parts begins.

[rswannabe]

Originally Posted by Danimal16

Thanks. I am learning about all of this. Is there a quick engine built on the 7R case. The search for parts begins.

Define what you mean by "quick". You can building anything from a 2.0 to a 2.9 on a 7R case. You can do short stroke (66mm crank) or long stroke (70.4mm crank). Possibly the easiest to find parts for would be a 2.7 RS spec motor with carbs in stead of MFI.

[kenikh]

The quickest, easiest, cheapest motor you can build goes like this:

70.4mm crank (dime a dozen)
84mm pistons from a 2.2E
Solex cams
SC oil pump

All of these parts are dirt cheap used in good shape and makes a nice high compression, eminently fun motor. You could find the parts quick, assemble it quick and have fun quick for far less than most combos.

[911 tweaks]

Kenik... can you elaborate a bit further on what else to do with your suggestion ??
I presume mfi for induction since you recommended using "E" heads ?? OR plug the holes & run carbs ?? (mfi ain't cheap so am I missing something here ??)
Lastly, what about timing (6 or 12 plug dizzy or something else ?? ) & exhaust to use ??

If one were to make this set up, what ballpark hp are we talking ??

...I think I am about to drop some coin here...

Thanks for your input here!!
Bob

[911 tweaks]

woops... sorry I missed that you recommend 84mm pistons from the 2.2E... so what does this mean for heads ??
Thanks again!
Bob

[kenikh]

Originally Posted by 911 tweaks

Kenik... can you elaborate a bit further on what else to do with your suggestion ??
I presume mfi for induction since you recommended using "E" heads ?? OR plug the holes & run carbs ?? (mfi ain't cheap so am I missing something here ??)
Lastly, what about timing (6 or 12 plug dizzy or something else ?? ) & exhaust to use ??

If one were to make this set up, what ballpark hp are we talking ??

...I think I am about to drop some coin here...

Thanks for your input here!!
Bob

Plug the holes and use carbs. Single plug dizzy is perfectly OK for this config, as CR is still only around 9.5:1. My guess is HP would be around 175 with a fat torque band. Use any 2.2 or 2.4 small port head (T or E is fine with this config).

[dipso]

Originally Posted by Danimal16

Thanks. I am learning about all of this. Is there a quick engine built on the 7R case. The search for parts begins.

Dan, This might help.
1975 2.7S with Carbs HP?