Finally!!! Something to Show on my Project
 

Sometimes I feel very academic since most of my contributions to the Pelican board are ideas rather then finished projects. It seems that most people get their cars fully restored in the time that it takes me to -- well get my P&C's! So here they are!
http://forums.pelicanparts.com/uploa...1126369689.jpg

Ta DA!!! http://www.pelicanparts.com/support/...ool_shades.gif

I just got my refurb'd cylinders back from EBS yesterday with my new set of 11:1, 85mm, 66 mm stroke, coated JE pistons Unfortunately 1 of the top fins on one of the cylinders broke off. Anyone have any experience if this will be show stopper or not? I'm using iron cylinders for cost and longevity reasons since this is my version 1.0 engine which is intended for my first couple of seasons of driver's schools, regionals and if I'm lucky and fast enough -- one or two nationals. I just hope that I'll be able to fill the tank with race gas by then!!!

If everything goes according to plan, by next spring I'll have the engine and gearbox built up to SCCA E-Prod specs. The only things left to get before I start assembly are...

* Maneflux and Balance the crank assembly
* Get the heads done and coated
* Engine rebuild gasket kit.
* An "M" gear. (preferably a trade rather then cash!)

These next acquasitions should go faster since the investments are less then new pistons.

SmileWavy

11:1? You going dual plug?

Race fuel. The GCR prohibits twin plugs and mandates 110 octane for E-Prod cars.

AHA; somehow missed that this was a race motor/

Are you sure? The GCR says any ignition may be used and allows machining heads.

Verrrrrrrry Interrrresting! It used to be on the spec line (I think), but in the 2005 GCR the spec line for the 911's in E-Prod is now empty. For comparison, the GT rules specifically allow it though in GT2, don't mention it in GT3, but prohibit twin plugging on the 914-6's in GT3. It looks like hap-hazard rules again.

Then again, Page 8 of the PCS, paragraph K2 allows any ignition system or component, "as long as there are no functional modifications of the engine required for their use". Drilling an extra hole in the head may constitute a "functional modification".

I'll have to think about this.

John , I most definately have a M gear. I though I sold you one previously? or was that an X?

anyhoo Im currently working in Burlington, Vermont.. Ill be traveling back to LI for the weekends, so shoot me a email on friday, and remind me to look through my box-o-gears

John, Maybe you can call someone at SCCA for clarification on the twin plug thing. I saw the 'functional' notation also.

That's a bummer on the fin. Maybe, being that aluminum is a great conductor of heat, the head will heat sink off any additional heat from that area of the cylinder.

I rebuilt a 2.4T a ways back that broke a couple of fins in shipping as well. Same place as yours. It happens if the cylinders aren't seperated by dividers in shipping. They sometimes overlap and when UPS drops the box :) the fins snap off.

I'm sure the motor will be great when it's done. I don't think anyone has researched more than you before doing a rebuild. Look forward to the results.

yeah, but he says his cylinders are iron, not as good of a heat conductor...

Some years back a friend lost a Solo national podium position because he had a twin plugged a 914-6 engine, even though he had removed the ignition for the second set of plugs, had no wires attached to them, etc.

Despite this being a non-functional modification (he used the second plugs in PCA events), he fell afoul of the the "no added material" rule - the non-working plugs. The holes, I guess were OK, under a rule allowing removal of material. But not plugging them back up.

That was then, and I haven't perused the GCRs for this question like you have, though I do know that in at least GT2 twin plugs are now allowed (were not back then - they were trying to keep out the 2.8RSR heads I think, and went about it in a roundabout way). But if they are not specifically allowed, one can argue that "any ignition" does not necessarily mean you can do some serious machining. Optical sensors, maybe crankfire, MSD, etc, yes. Those are bolt-on items. So something in there could bite you.

Walt Fricke

Thanks for the input. Given the mandated fuel (Only the 110 stuff meets the chemical composition that the SCCA checks for), I think that I'm going to keep with the single plug strategy for version 1.0 of the engine. I've got a second set of heads which will be fully done up for version 1.1 and if I chose at that time I can have them drilled or not depending on what I learn between now and then.

I think that the extra stability of the Iron cylinders will be a benefit, especially since the required carbs (40 mm's with 34 mm chokes) will most likely limit me to something in the neighborhood of 210 +/- HP. So it's not like this engine will be making huge amounts of heat like a Turbo. I'm also going down the thermal coating path to try to keep the heat issues contained. I'll have to see how that cylinder runs (plug inspection, EGT's, etc) after I get the engine built. Before I race it, I fully expect the engine to be dialed in on a chassis dyno, plus a couple of Driver's Schools and maybe a test day. So I really won't be "whipping the ponies" until the engine's got at least a few hundred miles on it.

I don't know if there would be an advantage to this since I don't know all the differences between the two, but the spec line only says IDA carbs, meaning you can use 46s rather than 40s if you want. Someone who knows more than me would have to say whether it's worth it or not. Just wanted to point it out though.

I guess it wasn't obvious what I was saying. I'm aware that the cylinders are made of iron. The heads, however, are made of aluminum. His cylinder has a broken fin at the top of the cylinder where it meets the head. If the cylinder is hotter than the head then the head will soak up some of the heat from the cylinder.

Of course valves generate a large portion of the heat in motors so it's entirely possible that the head might not soak up any additional heat at all.

Whatever the case, when you look at it percentage wise, I doubt that much cooling is lost from that missing piece.

Duh, very sorry, reading comprehension error on my part. I re-read it and your original post makes sense.

Given that I'm limited to a maximum of 34 mm venturi in the carbs, I don't think that there will be any great performance increase by switching from 40's to 46's, but there will be a big performance loss in my wallet!

Yeah John, I think you're right given the max venturi size. I only mentioned the 46's because I knew Porsche used them on the 2.0 R and 906 engines but they probably weren't restricted in venturi size.

It should be a fun project for you. It's nice to see more Porsches in SCCA Club Racing.

This year E-Prod has 50 cars registered for the Run Off's! :eek: By far the largest class. The majority are Mazda Mietas and RX7's. I think that there will only be 2 Porsche's, both 914's. A 914-4 2.0 and a 914-6 from Eric Madson.

By the time that I get done with mine they'll most likely be back to struggling for 15 cars. Don't hold your breath waiting for me to finish, you'll pass out... :rolleyes:

Down here in Florida SCCA races, I have yet to race against any other car in GT-2 BUT a Porsche.