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Posted by: bigkensteele Feb 26 2015, 10:19 PM

Topic 1: Has anyone ever tried mounting an oil cooler under a GT lid just above the fan, and if so does it keep the temp low enough for DE events?

Topic 2: Has anyone here ever adapted motronic from a 3.2 to work on a 2.7? If so, what is involved? Which distributor? What cam? Stock low compression CIS pistons or JEs?

Topic 3: What kind of power can I get if I keep the CIS but am willing to port the heads, change cams and go to JE pistons?

Please feel free to address any or all of the above? I have a '74 2.7 core that is currently torn apart and ready to send out for machining. It already has case-savers and nikasil jugs, so I am going to stay at 2.7. I have all of the CIS parts, so that is an option for induction, but I would rather do something else (other than carbs).

I will also be running stock 6 heat exchangers and a 911 muffler.

I just can't bear the thought of rebuilding this thing and only ending up with 150 hp, so any tips would be most appreciated.

Posted by: GeorgeRud Feb 26 2015, 10:26 PM

My 2.7 has RS pistons, S cams, and Webers with an Electromotive ignition. It put out 199 hp at the wheels, so you can get power. I'd investigate getting the Bitz EFI system if you have the CIS parts. You can't do much more cam retaining the CIS.

Posted by: campbellcj Feb 27 2015, 12:00 AM

In terms of the oil cooler, if you really don't want to do a front one then I think under the rear trunk would be better than the engine compartment. Under the engine lid you'd probably not get enough airflow and you'd have the heat coming from the engine baking the cooler the whole time.

I am not an FI guy but my guess is one of the popular aftermarket setups would be easier to implement than the 3.2 Motronic. You'll need to be able to tune it.

Posted by: mepstein Feb 27 2015, 06:21 AM

I would talk to one of the really good engine builders like Henry at Supertech. http://www.supertecperformance.com Someone who has a lot of experience building these engines and can get you the power you want depending on your budget. He's pricey but a lot cheaper in the long run than building an engine that your not happy with.

Posted by: Mark Henry Feb 27 2015, 06:24 AM

Topic #1 link

http://www.914world.com/bbs2/index.php?showtopic=111936&hl=Henry++Schmidt

Posted by: JmuRiz Feb 27 2015, 11:36 AM

Re: Motronic, I don't think I've heard of anyone using the whole system. Typically people use the 3.2 intake manifold and run something like megasquirt EFI to control it. That's possible with the turbocraft transitional spacers. I think someone on the pelican parts board is doing such a project. If I had a cheal 3.2 intake manifold (prices are going up), I'd give it a try.

Posted by: bigkensteele Feb 27 2015, 12:15 PM

That is what I had in mind, and that looks like the cooler I have. Thanks, Mark!

Posted by: bigkensteele Feb 27 2015, 12:17 PM

I should call Steve Wong to see if he has ever done a chip for a smaller motor.

Posted by: Steve Feb 27 2015, 01:46 PM

A 2.7 runs a lot hotter than an aluminum 3.0 or 3.2. I would go with a front cooler or under the rear trunk with a fan and grill to protect the cooler from rocks.

Posted by: bigkensteele Feb 27 2015, 10:40 PM

I will not (nor could I) run the thermo reactors used on the 75 - 76 911 motors. The core that I have is a 74 with an 11 blade fan. I will be running either headers or six exhchangers. I am not a metallurgist, but I cannot fathom how the single variable of case material (mag. vs. alum.) could account for any significant increase in thermo-retention, especially when compared to a larger displacement motor.

Not trying to be contentious, but I need to understand how an otherwise equal engine would run hot just because it was a mag. case 2.7 vs. a alum. case 3.0 or 3.2.

Thanks to all for the input.

Posted by: gereed75 Feb 27 2015, 11:18 PM

Not an experienced expert in 911's, but thermodynamics is thermodynamics. The heat generated to make say 180 hp will basically be same no matter what the engine is made of. The difference in heat carried away by either mag or AL cases would not be significant.

Timing can make a huge difference in the amount of heat generated by aircooled motors. More advance generates higher peak combustion pressures and can actually produce less HP. If your motor runs hot in a system that otherwise should provide adequate cooling, back off the timing a bit.

I suspect the "2.7's run hot" belief comes from the era when Porsche tried the thermal reactors to meet emissions.

BigKen, I suggest you burn some midnight oil on the Pelican 911 rebuild board. There is much to learn there.

Posted by: Steve Feb 28 2015, 01:21 AM

That was my experience. I have also heard the same thing from other people that have owned both. My first six was a stock 74, 2.7 motor with 40 webers and headers. It over heated all the time until I installed a front oil cooler. Same car, but instead of over hauling the motor, due to the common pulled head stud problem, I bought a stock euro 3.2 instead. Same climate, same cooler, but the 3.2 ran much cooler. I loved my 2.7 with the webers. It sounded amazing versus my stock 3.2. But I love the power of the 3.2 and the DME fuel injection is for the most part trouble free.

Posted by: GeorgeRud Feb 28 2015, 02:49 PM

When new, the 2.7 liter cars had oil coolers in Europe, but Porsche figured that we didn't need them for our 55 mph speed limit.

With a front cooler, they run just fine and are a nice size for the 914-6 conversions.

Posted by: Steve Feb 28 2015, 04:44 PM

I loved my 2.7 in my 914. You can run a stock 2.0 six flywheel and clutch and bolt right up to the 914 trans without an adapter. If my motor was overhauled correctly with race wear studs and case savers, I would of kept it versus going to the 3.2.

Posted by: bigkensteele Feb 28 2015, 05:43 PM

I have to say that I got lucky in that my case already has case savers. I have no idea what the studs are, so I will probably replace those to be safe.

I also found a 2.0 flywheel on fleebay, and I failed to inspect it closely when it arrived. I looked at it months later, and it has a few teeth that will probably need to be welded up and filed, if that is even possible.

Really excited about building this motor (first timer), but time and budget won't permit it to go quickly. That is probably a good thing as it will give me more time to learn and determine what I can do about induction.

Speaking of induction, the Bitz Racing Megasuirt kit may be the way I go since I have all of the CIS parts needed, and it is somewhat plug and play. However, I think that his kit uses MS 1, which I don't believe handles spark. I would obviously prefer a solution that handles spark as well.

So much to learn!

Posted by: Steve Feb 28 2015, 06:24 PM

If you don't own it already, check out Bruce Anderson's Porsche 911 performance handbook. Tons of information on the 2.7 and other aircooled 911 motors. He has an in depth section on the 2.7 stud issue. The latest release is the best, which I think was the third edition before he passed away. RIP...

Posted by: bigkensteele Feb 28 2015, 06:31 PM

I have the second edition, and it is a treasure trove of info. I have never read it cover to cover, but I have read several sections several times. Wayne Dempsey's rebuild book is excellent as well. I would never have the courage to do the rebuild myself if it weren't for that book.

More info on the Bitz kit that I mentioned above.

http://www.bitzracing.com/index.html

Posted by: SirAndy Feb 28 2015, 06:38 PM

Here are your two choices:

- Install a front mounted cooler now.

- Fiddle with other solutions, spent time and money only to find they don't work well, then install a front mounted cooler anyways.

Posted by: bigkensteele Feb 28 2015, 07:04 PM

OK, I get it already. And that leads to my next question.

Has anyone here ever done a trombone style in the fender well?

Posted by: mepstein Feb 28 2015, 07:07 PM

914 fenders do not get pass through air like a 911. Lots of threads on different oil cooler locations but like Andy said, the front is the most effective. It's just a pain in the wallet to get it there.

Posted by: bigkensteele Feb 28 2015, 07:42 PM

Problem is that I want to run an LE dam and I don't want to cut my bumper, so getting air into it is the issue.

I am not running fog lights currently. I wonder if enough air enters the grills to be effective? It's gotta go somewhere, right?

Posted by: Mark Henry Feb 28 2015, 08:20 PM

Some one did this and said it worked well, but it's two coolers and I believe he plumbed them in parallel. Used two AN-10 mesa coolers. I can't remember who did it but it was a member here.

Posted by: wndsrfr Feb 28 2015, 08:48 PM

Mine's like his but with PMO's, same as Webers & got a bit over 200 .....here's the graph:

Posted by: JmuRiz Feb 28 2015, 09:17 PM

Most cam with CIS pistons is an SC grind or maybe a 964 grind (I've heard it should work, but don't know anyone that's tried it).

I have the CIS and a good set of webers and sc grind cams, not sure what route I'll take yet.
A 200+ hp engine would be awesome, just need to see about $$ and what my existing parts condition.

Posted by: bigkensteele Feb 28 2015, 11:16 PM

I have a set of the Crane GE60 equivalents, but Bruce Anderson says that they are too much for a 2.7, so I am leaning toward a 964 grind. I am budgeting for 9.5:1 JE pistons rather than running the stock 8.5:1 CIS units. I did get lucky because my jugs are nikasil, so hopefully all they will need is a nice hone.

My hope is that if I bump up the compression to 9.5:1 with JEs and swap in 964 cams, I can get somewhere around 200hp with the Bitz MS kit and keep heat with the new Stoddard exchangers.

While I am in there, I will probably do the oil bypass mod if I can find a new pump. I may even try porting the heads with my Dremel. They are currently 32/32.

I can't find any local machine shop that I am comfortable with, so all of this is probably going to be sent to Ollies in AZ, unless someone can recommend an east coast shop.

Thanks,
Ken

Posted by: Van914 Mar 1 2015, 09:15 AM

Ken,
You can run a front cooler without changing the bumper. I just cut the LE spoiler to get air to the cooler. Never had a problem with temp. At the track with my 3.0ltr. I used a fiberglass reproduction shroud to direct air down through the trunk floor.
Van

Posted by: Steve Mar 1 2015, 09:22 AM

I plan on doing the same thing with my chrome bumper.
Getty design sells the shroud. You can also see pictures of it in my blog.
http://www.gettydesign.com/914_bodywork.php#gtoil
I am running a mocal thermostat. I would also recommend a fan under the shroud if you plan on driving it on the street and get stuck in grid lock traffic. Otherwise for the track and open freeway, it will never overheat with the above setup. Patrick Motorsports sells a cooler that fits in there perfect. You could also use a Mazda RX7 cooler, but you will have to cut the shroud a bit to make it fit. I'm running the Patrick cooler with standard steel braided line down the rocker panel like the GT cars,

Posted by: SLITS Mar 1 2015, 10:28 AM

Jim Lamonica did it on his 3.6. I believe his log on is "six" here or on Club Narp.

Posted by: campbellcj Mar 1 2015, 11:41 AM

I cut a notch out of an LE spoiler as well. I use different spoilers on the track, but this one has seemed fine on the street. Bear in mind that just adding the cooler also adds a lot of oil capacity and a lot of surface area in lines and t-tstat. That helps too.

Posted by: gereed75 Mar 1 2015, 11:59 AM

I recomend Craig Garret (Cgarr on Pelican board). He just did an excellent job on a set of heads for me. Ported 32 out to 36. He also does case savers and the bypass mod but he does not do line boring.

At the very least, talk with him about your heads. He is very reasonable, does great work and is relatively quick and is very easy to deal with. At his prices, I would not screw around trying to do the ports yourself unless you are looking for the experience.

Posted by: GeorgeRud Mar 1 2015, 04:40 PM

Ollie's should be a great choice. Since mine had been previously rebuilt many years ago, I sent the long block to Henry at Supertec in Fallbrook, CA to do the last one. Couldn't be happier with the rebuild and the turnaround time. Not cheap, but you get what you pay for (see Motormeister).

Posted by: JmuRiz Mar 1 2015, 06:51 PM

FYI when pricing out a 2.45 for my brother, Henry's prices didn't seem too bad compared to others. If I didn't have a local guy to check mine out, I'd probably send it over to him.

Posted by: bigkensteele Mar 2 2015, 06:57 PM

Thanks to all for the responses. I was looking for more seat of the pants and personal experience opinions/data than what I have found in the Anderson and Dempsey books, and you guys have provided that.

My vision is a bit more clear. Leaning toward the Bitz MegaSquirt kit with a custom air box, trying out the GE60 cams that I have with JE 9.5:1 pistons and having the heads ported a bit. This should put me close to my 200 hp goal without spending stupid money. I am still thinking that the external cooler is going somewhere in the back of the car and finding out at the first DE or AX if that is going to work.

One more question - I am not sure that I want to weld an O2 sensor bung(s) into the new heat exchangers that I plan on buying. Would a bung or bungs in the muffler work?