JimConner

This is true. The rod weight isn't really a big consideration. Just look at the weight of the rod vs the piston, I bet the piston weighs 4x as much. Also, as BRAAP said, the big end of the rod is mostly considered part of the crank, and the small end is considered part of the piston. Also, a lighter piston will let the engine accelerate faster, which will make the car faster but won't necessarily show up on the dyno.

I would avoid popup pistons as they are heavy. Usually, "Keith Black" means HEAVY around 500g. I would look for dish top or flat top. (Then use a small CC head or mill the head) How about this: JE 181920 4.03 with 1.425 CH. It is a 383 piston with 5.7 rod. You'll use a 6.0 rod of course.. For $100 you can have a machine shop deck the pistons 0.020 (plenty left for strength etc). The piston will then be lighter than its original 424 g weight. http://www.flatlanderracing.com/jepistonchevys305.html And same deal, just a bit heavier at 489g: http://www.probeindustries.com/ProductDetails.asp?ProductCode=12336&Show=TechSpecs Here are some moleculite at a mere 376g: http://www.probeindustries.com/ProductDetails.asp?ProductCode=14105&Show=TechSpecs With a 58cc head that is about 10.5 to 1. Those are all for a conventional 23 degree head. Oh also.. don't forget to make sure the piston matches the rod as far as full floating vs press fit. I don't know which those factory rods are, but usually press-fit..

I don't see how you can consider rods without thinking about pistons. You need to match the compression height of the piston to the crank and rods and deck height. You could get the rod you "want" and then have to get custom pistons because of the compression height needed.

You should contact Jay Allen at http://camshaftinnovations.com for the cam.. $400 for a billet roller, and I am sure he could alter the firing order. Tell him EXACTLY what you are looking to do, and he will spec out the cam for you and grind it. He is also a wealth of information on ALL things engine-related and will give you lots of advice on your build. A cam/spring/retainer/locks package will probably run around $600 or 650, though obviously he would be the one to ask for a definitive answer. I would just fill out a build sheet, email it to him, and wait for an answer. (He is very busy apparently).

Then grind it down to a 1.88 Honda rod journal for 3.12 stroke! I'm just sayin'... You could maybe even destroke the crank and then bush the rod journal or use oversize (thick) bearings. Also, whichever journal you use, try to make sure it's not just a 2.1 rod forging with less material taken out of the journal area. Some small journal 2.0 rods are heavier than 2.1 rods for that reason.. Know what I mean? EDIT: Also, what are you using for a harmonic damper? Sure, it will be zero balance. But aren't the available dampers "tuned" for a standard V8? Or will they work just fine on a flat crank?

Another thing I thought of.. According to what I've read, the Ferrari F355 V8 has a 3.03 stroke and NO balance shafts. The Ferrari F430 V8 has a 3.19 stroke and DOES use balance shafts (3.62 bore). http://www.ls1tech.com/forums/8976152-post22.html Given your 3.24 stroke, you may need balance shafts. Of course, the F430 redline is 8500 and yours will be significantly less, which should help. This may be a "trial and error" kind of thing. Rev it up and see how much it shakes! Anyway, now to the point of my post. If your journal size is 2.10 you should be able to offset grind it down to a 2.0 journal for a 3.14 stroke, and use small journal rods. Grinding the crank should cost about $250. A side benefit is the reduced weight of the crank and rods.

It would be a CRYING shame to put heavy "el cheapo" pistons on this work of art! Though I have never used them, I hear the hypereutectic pistions are lighter than forged, and should easily be strong enough for what you are doing. I would simply look for the lightest piston I could find. Using a long rod should help you with that by allowing the piston to be shorter. I would not worry about the oil ring being in the pin, I would just go for the lightest/shortest piston I could find. Just make sure the wrist pin centerline doesn't come out the bottom of the bore at BDC.. Also, what's the size of those throttle bodies?

Never mind the pictures.. I want details!! :) Where'd you get it and how much? What's the story behind it? What bore size are you going with? Maybe some SB2 heads? EDIT: Oh I almost forgot... WHAT DOES IT WEIGH??!!

I'll ask the obvious question. How much for ten cranks instead of just one? I wonder what they would do it for, now that the economy is in the tank.

Welcome to the board paulmer! Where is that GT40 thread you were looking at? Also, just my personal opinion, as far as a 4.0 liter V8, the Toyota 1UZ-FE is a great motor, and likely easier to find parts and cheaper to maintain.. Or are you saying the BMW motor has a flat plane crank? :)

..... Having said that, the X-pipe is just a second best option to 180 degree headers. There is NO difference between a flat plane crank and just using 180 degree headers on a dual plane crank. OK well there are differences in the balance and weight which will allow a flat plane to rev quicker.. Anyway power production with an X-pipe has been shown to be within a fraction of a percent off from 180 headers. There used to be a bunch of good articles at drgas.com but I don't see them now. But I would be willing to bet that other factors play a very important role in the sound: -- 5-valve design and the progressive nature of the valves (they open the outer valves first i think) -- engine size of 3.5 liters -- rotating assembly weight (or lack thereof) -- camshaft specifications (overlap, etc) http://ferrarichat.com/forum/showpost.php?p=36869&postcount=18 -- compression ratio -- short exhaust length, and muffler configuration: http://www.ferraricars.org/ferrari-f355/drivetrain.html Ideally you need to match all those parameters, but my feel is that with the flat plane crank or 180 headers, AND a small engine size of 3.5 liters, you would be 80% there.. Check this out: http://www.youtube.com/watch?v=LLqflRvUgKc I realize the idle is choppy, but listen when it is under load. If the engine were smaller, I bet it would sound similar to an F355. This is looking more and more like you should just get that F355 engine and be done with it Rather than spend $5k on something that is not quite right, why not spend twice that and get the real thing? Then figure around 2k per year for maintenance and upkeep, doing the work yourself. http://www.ferrarichat.com/forum/showthread.php?t=198430

This pic is just for 3 months from now when eBay deletes the listing and the image goes away.. OK I am offering the guy 6k

http://cgi.ebay.com/ebaymotors/Ferrari-355-engine-F355-V8-3-5L-only-8-000-Miles_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem3599c345e3QQitemZ230212978147QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories heck I am tempted to hit "buy it now" !! edit: looks like an unusual header design too: http://cgi.ebay.com/ebaymotors/Ferrari-355-OEM-exhaust-manifolds-headers-F355-Tubi_W0QQitemZ150365835613QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item230280915d&_trksid=p4506.c0.m245

1. The Ferrari engine is much smaller than an American V8. F355 is 3.5 liters compared to typical American V8 of 5 to 7 liters. 2. Ferrari F355 has 5 valves per cylinder.. I think an X-pipe gets you 90% there.. Then make a small engine. Also, a short exhaust system helps. Perhaps a side exit behind the front wheel? Listen to this GT40.. 180 degree headers plus short exhaust system equals exotic sound. I think it sounds a bit like a deeper version of the F355: http://www.youtube.com/watch?v=Hcb3zHZuEUU I would be willing to bet that the intake system is a factor, too. Try an ITB system and it will look good and perform well in addition to sounding good. Here is a large engine with just the X-pipe and some spintech mufflers: Do this in a 3.5 liter engine and bingo! Come to think of it.. I wonder if it isn't the engine size, but rather the exhaust pipe size... smaller engines tend to have smaller pipes. food for thought..

So what was the result?