2.2 rebuild advice please

teachkenpo · 06-09-2009, 02:49 PM

Hi, I am in the process of restoring one of my 66 911's. It was a shell only with many mods and repairs, and never going to be stock again so I am making it an R clone. Since it had no engine, I am planning on using a 2.2 that I obtained from a friend. He found that it had low compression in one cylinder and he pulled the pistons and determined that it needed rings. I have the rings, but have not started any work yet.

What I am looking to accomplish is to build a totally fun car/engine combination. Since I already have 2 stock 66's with standard 2.0's, I want this one to be more appropriate for the R theme I am seeking. In looking through Wayne's book, I read with interest about upgrading this engine with a 2.7 crank to make a 2.4. It led me to a few questions that I am hoping someone can answer.

1. Since replacing the crank will require opening up the case, are there any other worthwhile modifications that I can do without opening the case. My logic is that since I have never done a rebuild, maybe I should just start with the top end and see how it goes. Wayne's book makes me feel like I can do it, but it just adds more time and money.

2. If I am going to open the case and replace the crank to make it a 2.4, would you opt for an E or S profile? I understand the low end torque issues with an S profile, but S car drivers seem happy with their S motors, and I have other cars I can drive if I am feeling tamer.

3. Should I scrap the 2.2 to 2.4 rebuild and just build or buy a bigger motor?

4. How much horsepower can reasonably be achieved with the various rebuilds below (without very expensive options like twin plugging)

Rebuild the 2.2 to E specs
Rebuild the 2.2 to 2.4 E Specs
Rebuild the 2.2 to S Specs
Rebuild the 2.2 to 2.4 S specs

What is your opinion on which way to go with the rebuild.

Thank you in advance for your help and suggestions.
John

kenikh · 06-10-2009, 06:53 AM

I'll assume the motor is a T from your description. If so, going to non T cams will require new pistons, too. I'd have Supertec bore the Biral cylnders to 85mm. Boring a 2.2 case to 2.7 isn't a great idea, since these cases are a bit weak for that, but you can get away with it w/ E or milder cams. Get some 9.5:1 CR JEs, a 2.4 crank, some used Solex, E, S or Mod-S cams (I have Mod-S for sale, BTW

) and you'll get a long stroke 2.3. You will need to port your heads for anything hotter than E or for any 2.7 option, though. You'll get a fun motor with any of these.

teachkenpo · 06-10-2009, 09:11 AM

Quote:

Originally Posted by kenikh

I'll assume the motor is a T from your description. If so, going to non T cams will require new pistons, too. I'd have Supertec bore the Biral cylnders to 85mm. Boring a 2.2 case to 2.7 isn't a great idea, since these cases are a bit weak for that, but you can get away with it w/ E or milder cams. Get some 9.5:1 CR JEs, a 2.4 crank, some used Solex, E, S or Mod-S cams (I have Mod-S for sale, BTW

) and you'll get a long stroke 2.3. You will need to port your heads for anything hotter than E or for any 2.7 option, though. You'll get a fun motor with any of these.

Hi Kenick,
Thank you for your reply. I have a few questions about your ideas.
1. When you are suggesting new pistons, are you talking about 2.2 or 2.4?
2. In Wayne's book, he comes up with a 2.2 or a 2.4 displacement depending on crank choice, but in both cases he suggests 2.2 pistons. How does your suggested combination achieve 2.3?
3. If this combination yields a long stroke 2.3, is that better or more horsepower than the 2.2s or 2.4s suggestions in Wayne's book?
4. How is a Mod S cam different from an S cam? (You can PM me a price for yours)

Thanks,
John

kenikh · 06-10-2009, 10:04 AM

Quote:

Originally Posted by teachkenpo

Hi Kenick,
Thank you for your reply. I have a few questions about your ideas.
1. When you are suggesting new pistons, are you talking about 2.2 or 2.4?
2. In Wayne's book, he comes up with a 2.2 or a 2.4 displacement depending on crank choice, but in both cases he suggests 2.2 pistons. How does your suggested combination achieve 2.3?
3. If this combination yields a long stroke 2.3, is that better or more horsepower than the 2.2s or 2.4s suggestions in Wayne's book?
4. How is a Mod S cam different from an S cam? (You can PM me a price for yours)

Thanks,
John

When I suggested new pistons, I meant going with 85mm JEs, which can be used on either crank. Just make sure to tell the builder which crank you will use so they can adjust the piston domes for CR.

Both 2.2 and 2.4 use 84mm pistons. The discplacement increase is due to a 4.4mm longer stroke on the 2.4.

I misspoke - the 85mm on the short crank result in a short stroke 2.3 or a long stroke 2.5, depending on crank.

Mod-S cam makes more lift and has wider lobe centers than the S cam - it makes more HP and torque than an 'S' since it uses slightly fast ramps to open and close the valves. It is a more "modern" profile.

My cams are for sale here:
FS: New Mod-S Cams (DC40, GE40)

teachkenpo · 06-10-2009, 12:10 PM

Hi Kenik,
I think I understand now. With 84mm pistons you get 2.2 or 2.4 depending on Crank. With 85mm pistons you get 2.3 or 2.5 depending on crank. With a S or Mod S cam, what kind of horsepower is attainable with these setups? Also, I saw that your cam was set up for mfi. I only have 40 webers, would your cam still work?
Thanks,
John

kenikh · 06-10-2009, 12:40 PM

Quote:

Originally Posted by teachkenpo

Hi Kenik,
I think I understand now. With 84mm pistons you get 2.2 or 2.4 depending on Crank. With 85mm pistons you get 2.3 or 2.5 depending on crank. With a S or Mod S cam, what kind of horsepower is attainable with these setups? Also, I saw that your cam was set up for mfi. I only have 40 webers, would your cam still work?
Thanks,
John

Yes, MFI cams work fine with carbs; you just need to run the MFI cam housing seal or cut off the MFI mounting boss. The seal is easy to install. The cams profile itself is 100% identical.

A long stroke 2.5 on 'S' cams should make about 215HP (195HP, 2.3L) at the crank on 9.5:1 compression and single plugs. A Mod-S should make more torque thorughout the powerband and 5-10% more peak HP.

teachkenpo · 06-10-2009, 01:05 PM

Quote:

Originally Posted by kenikh

A long stroke 2.5 on 'S' cams should make about 215HP (195HP, 2.3L) at the crank on 9.5:1 compression and single plugs. A Mod-S should make more torque thorughout the powerband and 5-10% more peak HP.

Now that sounds like the kind of power that will make a SWB car come alive! I have a call into Henry at Supertec to find out about the cylinder boring and other machining. I have called JE about the pistons, and I will make a decision about the cam. I guess I am on the lookout for a good crank now. Thanks for your suggestions.
John

kenikh · 06-10-2009, 01:10 PM

Henry has a great relationship with JE and they are right down the road from him. I'd work through him to get the set matched. I also have a nice set of 85mm JEs that I bought from Henry a few years ago (new), so I have experience in this area, but the CR doesn't meet your needs since they would require twin plugs.

Dan Morton · Dan Morton's Garage

If you are going to do mods, I would suggest you open the case so you can check the bearings, crank, case, etc. I would be hesitant to do mods otherwise since you really don't know the condition of those parts. Once you open the case, you can factor in $1,500 for parts just to put it back together (bearings, gasket kit, etc.) Add any machining that would be needed. Then add the cost of your mods. If you do it yourself a rebuild could run $4-5k before you buy P's&C's. Bottom line, it's expensive so plan your rebuild right.

I am just finishing a total rebuild on a 2.0 and was able to re-use the P's&C's (2.8rsr), crank, cams, etc. I sent all parts out to be machined and heads reuilt. The total cost just for maching was over $3k! I think I'm in around $4,500 at least.

I also had my 2.2 engine rebuilt a few years ago with new 2.2S Mahle pistons, E cams, and it was about $10k with labor. The power is nice but you would probably want more for an R.

IMHO I would think with the cost of rebuilding the car, you may want to just get this engine re-ringed and then plan the big rebuild later.

teachkenpo · 06-11-2009, 09:22 PM

Hi Dan,
I really appreciate your candid assessment regarding rebuild cost. I have been tempted to just put the rings in and run the engine for now and do something bigger later. Then I think that when this car is finally done, I want it to be something special. I am looking at this car as a test bed to see what I am capable of. If the project goes well, I will rebuild/restore the other three 66 coupes to more original condition. I am driving 2 of them already, but they should eventually all be redone from the ground-up.
Unlike the other 3, the 66R is going to be a mongrel. It won't even be close to stock, so I feel like I can do something wild with it and not feel guilty for bastardizing it.

Lets face it, half the fun of these cars is in the planning and the dreaming. The other half is in the driving. I am trying to get my fill of both.

John

Dan Morton · Dan Morton's Garage

John, it sounds like you have a lot of fun projects! It's great to have three early 911's for sure. I'm like you, I want to drive and enjoy. My '68 should have the engine back in this weekend so I can finally drive it after several months of being torn apart. Then of course I will move to the front half of the car to rebuild the suspension. Then one of these days I'll put it back to it's orginal condition (strip the RSR flares).

Good luck with your project. I'll be curious to see if the new rings works out well enough. BTW, I have 3.0 case, crank, cams, rebuilt heads, plus the gasket kit, raceware hardware, and some other bits that I may end up selling if you're interested in building on a 3.0.

-Dan

teachkenpo · 06-13-2009, 10:06 PM

Hi Dan,
I have not made a decision which way to go with the rebuild yet. I keep getting distracted by other more urgent projects with my other cars. There always seems to be something breaking down. I may have to pull a transmission and do a rebuild. Another project I have never done before. Not what I want to work on right now.

I still have another car without an engine, so pm me with the specifics on your 3.0. Also, please post some pictures of your car once you get it running. I never get tired of seeing those SWB cars.
John