Possible Engine Builds

[keith951]

Alright here is my situation.

I have an 88 Turbo S that was wet sleeved to 2.7L.. The #2 cylinder has slight scoring. I am going to drop the pan soon and see what went on.. I believe the skirt on the piston got bent and messed up the sylinder wall.. It is not a deep enough score to be from a broken ring or something of that nature.

I have been toying around with different ideas of what to put in this car.. It has double adjustable konis front and rear.. widband 02.. ect ect.. so the brakes and suspension are ready to handle to power.

I also have a spare 968 engine laying around.. so know I have alot of different options to play with.

Here are my different ideas

1.) Just keep it like it is.. hone the cylinder and assuming the pistons are damaged.. Call JE and either order another set or send one in and have it matched. (Would probably be expensive to have one piston made)

2.) Take the 3.0L crank out of the 968.. put it in the 2.7L block to make a 3.0L Stroker.

3.) Take the 3.0L block.. source a 2.7L NA head.. make a 3.0L turbo and buy some lower compression pistons.

What do you guys think the best bet would be.. I could make some money back selling the spare heads (2.5L turbo S head and the 16v 968 vario cam head) if I go with option number 3.

Also.. with option 1.. I could just sell the whole 968 engine whole and there would be my money for the pistons and other stuff I need.

If I go with option 2.. i Probably will have trouble selling the rest of the 968 engine stuff.. and I guess I could dump the turbo S head for some spending money.

If I go with option 3.. Im going to want to buy a bigger turbo (Currently have the 26/8, 55 lbs injectors, ect ect.

Would I be able to use the stock 3.0L rods with this? and what kind of pistons are the best ones to start looking at?

Also, which option would be the most cost efficent, put out the most power, ect ect.

Any one that has alot of knowledge on the topic, please chime in and let me know what the best route to take would be.

Thanks,
Keith

[TNT25169]

I've heard you can't use a 3.0L crankshaft in a 2.7 L block. Something about clearences and damage to the crank. I've been trying to get a clear answer on this for some time now. I will post an email I got from a group on yahoo. I have a 2.7L block and I know where to get a 3L crank for under $1000 so I'm mulling over options as well.

[keith951]

I talked to someone at lindsey racing and they said it will work.. and the 2.7L block with the 3.0L crank will give you a 3.0L stroker.. just going to need a set of 3.0L pistons.. And you can get a ser from J&E for like 699.99 from lindsey racing..

Any one else want to chime in on what they think?

TNT keep me updated on what you find.

Thanks,
Keith

[TNT25169]

Here is the email:

"The 3.0L crankshaft is specifically machined for the "linerless" siamesed cylinder casing of the S2 motor only. Throwing it into am 8V 1989 M44/7 engine may cause piston slap, as the tolerances of the 3.0L crank are slightly off the reciprocating range of the 8V block. Not only that- it will also grind the rod bearings inside their journals, therby making it toast(we've already tried it, in 1990). Your best bet is to keep the existing 2.7L crankshaft, and stroke-up displacement, using the the shorter-throw Pauter, or Carillo connecting rods, with the recessed-crown, forged turbo pistons. The good news is the 968 pistons can also be used with the shorter rods, if you want to widen the bore closer to 3.0."

I'm still not sure what to make of it. I have a feeling you have to use the whole bottom end from a 3.0L and the '89 2.7L head. That is the only thing that makes sense to me because the flow channels align and you wouldn't have to worry about crank interference. Throwning a 3.0L crank in the 2.7L block seems too easy but still....no one seems to have a clear answer.

[armandodiaz]

I think the problem with interchanging the block/crank are the stock connecting rods are too thick. You will need aftermarket rods rougly $1200