A 2.2L Upgrade Build - Questions

scootermcrad · 05-17-2023, 11:48 AM

Hey everyone!

I have a 2.2L 1970T motor that I have acquired. I have been reading and thinking through some potential build options to suit the needs of what will just be a street car with the occasional track day or two, just for fun. I have the recommended books and from that have come across the ol' 2.5L long stroke recipe that seems like a good fit for this engine. I even have a 70.4mm crankshaft that came with my car when I bought it, as an added bonus. I've run across a few well documented builds here, that further reinforce the idea. I have a handful of questions, though...

My cases are 2/3R cases, which of course are not the most ideal cases, but are what I have and it still seems many of 2.5L builds have been done with the obvious upgrades and case work. One of the things I wonder about is a boost in compression and twin-plugging. The recipe in "the book" shows the build as pretty high compression, but not twin-plugged. which surprised me. It was right at or close to 10:1. (need to look again) I'm comfortable with the idea of twin-plugging the motor and possibly even trying to achieve 10.3-10.5 ish. Am I asking for too much from the 2/3R cases? I'm assuming it would be worth adding piston squirters, as well? (however that is accomplished)

This brings me to cylinder questions. There's obviously a lot of topics covering P&C's and what brands are ideal and which are now sort of questionable. I was trying to find some information on using factory STOCK cylinders and boring them and just buying good quality pistons to achieve what the recipe needs, but I can't seem to find the threads or information on the pros and cons of doing this and if it's worth messing with. If I remember, there were some that could not be machined, (or shouldn't) If someone could enlighten me on that subject, or point me to some threads on the topic, I would appreciate it. Or if you want to tell me, "that's a dumb idea, just buy a P&C set from XYZ and move on", that's okay too. I'm always just trying to be resourceful. These engines aren't getting any cheaper to build, as we all know.

An additional pipe dream idea I was thinking about, sort of for fun, and WAY out in left field compared to a "simple" 2.5L build, was to potentially build a tribute to Alan Hamilton's single turbo engine that was run in the mid-engined Queensland 911 (around 1975). It used a 66mm crank, 83mm cylinders, lower compression, etc. I'm trying to keep the flavor of an early era build (pre-1975) and this sort of intrigues me, since Porsche hadn't come out with the 930 yet. I'm guessing I would have to have a 7R case to do something like this. I'm assuming a 2/3R case set would be too weak for a build with forced induction and not worth making any major modifications to, for this kind of build. Would that be a fair assumption? That would also become an injected motor (most likely EFI and not a Bosch MFI), so would I also need to run a different head than the 2.2L T heads?

Here's the Hamilton engine, for some eye candy. Pretty neat!

Thanks for any insight and chatter. And I apologize if I've missed the obvious answers. I promise I searched for them. I was kind of surprised I didn't turn up more. I know I've seen some of these discussions. I just couldn't seem to find them in a search.

scootermcrad · 05-17-2023, 03:54 PM

Doing a little more research on the Hamilton 2.1 Turbo motor, this was either one of the four 1974 2.1 RSR motors, or it was built to the same specs. Definitely fascinating! The questions still remain regarding building a 2.1 (or even a 2.5l) turbo, though. 2/3R cases for a foundation possible??

Also, I tripped over a discussion regarding cylinders and it seems using 86mm Biral type cylinders might be the only option for boring and would only want to go to 86.7mm to achieve 2.5L (2.492). But are these cylinders easy to come by or even worth boring?

crater64 · 05-18-2023, 06:37 PM

Quote:

Originally Posted by scootermcrad

Also, I tripped over a discussion regarding cylinders and it seems using 86mm Biral type cylinders might be the only option for boring and would only want to go to 86.7mm to achieve 2.5L (2.492). But are these cylinders easy to come by or even worth boring?

I'm currently in the process of having built a 2380cc motor using 87.5mm Nickies with my stock 66mm crank and rods. The Nickies are a slip fit in my 2.2T case. I'm also going twin plug as I bought the Nickies with 10.5:1 JE pistons as a package from LN Engineering.

Uwon · Uwon's Garage

Following, got a ‘71 2.2T motor …..
Johan

scootermcrad · 05-19-2023, 03:07 AM

Quote:

Originally Posted by crater64

I'm currently in the process of having built a 2380cc motor using 87.5mm Nickies with my stock 66mm crank and rods. The Nickies are a slip fit in my 2.2T case. I'm also going twin plug as I bought the Nickies with 10.5:1 JE pistons as a package from LN Engineering.

That's sounds like an exciting build! Is there a build thread for this?

scootermcrad · 05-19-2023, 03:17 AM

I'm feeling it's safe to say that 2/3R mag cases should never be considered for a boosted build, so I'll simplify the discussion a bit.

* Can I recycle 2.4L Biral cylinders and have them bored to 86.7mm and is it worth the trouble, if so?
* What about installing oil (piston) squirters in a 2/3R case set? Recommended? Suggestions?

scootermcrad · 05-19-2023, 03:23 AM

I'm feeling it's safe to say that 2/3R mag cases should never be considered for a boosted build, so I'll simplify the discussion a bit.

* Can I recycle 2.4L Biral cylinders and have them bored to 86.7mm and is it worth the trouble, if so?
* What about installing oil (piston) squirters in a 2/3R case set? Recommended? Suggestions?

crater64 · 05-19-2023, 03:24 AM

Quote:

Originally Posted by scootermcrad

That's sounds like an exciting build! Is there a build thread for this?

This is a kinda build thread but it was more me trying to figure out whether I could get away with using my Zeniths. Instead I went with Weber 40s and was able to sell the Zeniths to someone who was restoring yet another 2.2T to stock.

Zenith jetting recommendations, 2.4SS

Henry Schmidt · Henry Schmidt's Garage

A 2.5 liter long stroke we built for a 914-6 street car.

CUSTOM BUILT TO 2.5 PERFORMANCE SPECS (210+ HP)
87.5 mm 9.5 TO 1 COMPRESSION CP PISTONS (thermal & dry film coated)
BESPOKE BIRAL CYLINDERS (Supertec)
2.4 /7R ENGINE CASE
2.4/2.7 CRANKSHAFT 70.4 mm stroke
DRC BILLET CAM SHAFTS DC30 (mod Solex)
BIG PORT 911 2.7 CYLINDER HEADS (36MM)
SUPERTEC HEAD STUDS
AASCO VALVE SPRINGS
TITANIUM VALVE RETAINER
*MAIN BEARINGS (FACTORY)
*ROD BEARINGS (CLEVITE)
*INTERMIDIATE SHAFT BEARINGS
CARRERA OIL PUMP (Supertec flow modification)
COMP TIMING CHAINS AND RAMPS
SUPERTEC TENSIONER ARMS
930 TURBO CHAIN TENSIONERS
MaxSpeed FORGED CHROMOLY H BEAM RODS
*RECONDITION ROCKERS AND SHAFTS
COMPLETE ENGINE BALANCE
COMPLETE VALVE JOB W SILICON / BRONZE GUIDES
36 MM INTAKE PORTS 35MM EXHAUST
CUSTOM MACHINE TURBO VALVE COVERS
* DRY FILM [CT1] COATING

Henry Schmidt · Henry Schmidt's Garage

Continuing the mid-engine turbo theme, this is a 2.5 liter short stroke engine I built for a club racer back in the late 80s. The case was an aluminum 2.0 with stock crank, 90mm RS pistons/cylinders and Carrillo rods. It used 2.7 heads and a custom built 930 CIS with fan cooled inter-cooler.
It made 345 on street gas with 1.0 bar of boost.

scootermcrad · 05-19-2023, 07:00 AM

Quote:

Originally Posted by crater64

This is a kinda build thread but it was more me trying to figure out whether I could get away with using my Zeniths. Instead I went with Weber 40s and was able to sell the Zeniths to someone who was restoring yet another 2.2T to stock.

Zenith jetting recommendations, 2.4SS

Lots of great work here! Thank you for sharing!

I have a nice matched pair of Zeniths and have been looking at modifications for them, also. A buddy of mine with a shop in Germany has been doing some successful builds with updated venturis and has been giving me some pointers. I'm going to start with them and see how they do. If I don't like them, someone will get a nice rebuilt set and I'll find another option. Webers, or maybe even explore EFI/ITB's of some sort, if I can get them to look right. I'm really trying to keep the car visually pre-1975, and newer EFI/ITB's might be a step too far. Drivability might be amazing though, which would trump everything else. I'll cross that bridge when I come to it. This is a pretty long term build.

Thanks again for sharing.

scootermcrad · 07:16 AM

Quote:

Originally Posted by Henry Schmidt

A 2.5 liter long stroke we built for a 914-6 street car.

CUSTOM BUILT TO 2.5 PERFORMANCE SPECS (210+ HP)
87.5 mm 9.5 TO 1 COMPRESSION CP PISTONS (thermal & dry film coated)
BESPOKE BIRAL CYLINDERS (Supertec)
2.4 /7R ENGINE CASE
2.4/2.7 CRANKSHAFT 70.4 mm stroke
DRC BILLET CAM SHAFTS DC30 (mod Solex)
BIG PORT 911 2.7 CYLINDER HEADS (36MM)
SUPERTEC HEAD STUDS
AASCO VALVE SPRINGS
TITANIUM VALVE RETAINER
*MAIN BEARINGS (FACTORY)
*ROD BEARINGS (CLEVITE)
*INTERMIDIATE SHAFT BEARINGS
CARRERA OIL PUMP (Supertec flow modification)
COMP TIMING CHAINS AND RAMPS
SUPERTEC TENSIONER ARMS
930 TURBO CHAIN TENSIONERS
MaxSpeed FORGED CHROMOLY H BEAM RODS
*RECONDITION ROCKERS AND SHAFTS
COMPLETE ENGINE BALANCE
COMPLETE VALVE JOB W SILICON / BRONZE GUIDES
36 MM INTAKE PORTS 35MM EXHAUST
CUSTOM MACHINE TURBO VALVE COVERS
* DRY FILM [CT1] COATING

Henry, that's a beaut!! Thanks for the break down, also! I appreciate that!

I know you've been busy building a lot of stuff (full barn!!). The motor you shared is built on a 7R case, and assume it already had the piston squirters. What can you tell me about installing squirters in a 2R or 3R case? It looks like the location bosses are actually there, but not drilled. Is this worth doing?

Also, have you built this same recipe with more CR and twin plug? I noticed PMS sells a Mahle 2.5L kit with an advertised CR of 10.5:1.

Thank you for sharing!