m42racer

Reading all this gives me comfort that what I am having done is not a waste of time. As a further alternative, the engine I am having built is based upon a 2.5L engine only. I decided to stay with the 2.5L engine as the parts are going to be available to all, and the most common engine size is still the 2.5L. I'm told, we will have performance worth staying at this size.

I asked today some of the weights of the stock parts. The stock Rod weighs in at at wopping 800+ grams and the Piston with Rings Pin and Clips comes in at over 700 grams. With a total weight of over 1500 grams, its doesn't take much to understand why the balance shafts are in there and why these engines rev slow and are limited.

The stock Rods are 150.00mm long C to C, and the Piston comp height of over 40.00 mm with a 24.00 mm pin with thick wall to boot, gives this engine an appearance of a tractor. If performance that has been stated can be had, think of what can be had when some up to the minute engineering is applied.

I am been sworn to secrecy about my spec's, but as soon as everything is finished, everything will be available. I can tell you that weight has been a major factor in design, along with Piston speed and the dwell time to help with the scavanging.

The Cylinder head was also looked at and the stock 2.5L Turbo head selected offering the ability to add larger Valves, and lower the shrouding. The volume has increased, but the Piston Volume and a slightly larger bore has kept the compression ratio up there.

The one thing I can say is the Exhaust ports are a huge limiter to flow. They do not flow anywhere close to where they need to flow. The ceramic lining has been removed, ports reshaped, and the ceramic re applied. The need for a junk head is required to re apply the ceramic, then destruct it to see if it sticks as it should. We will see.

Progress is becoming faster on this project, now that the EFI system and testing is done and finished. Hope to have a finsihed block to show off very soon.

Russ Murphy

m42racer,
Please do keep us aprised. Using the 2.5 head and block is a great thing. I plead ignorant to engine component masses. Are there 800g piston/combos out there, or are the weight savings liable to be 10-15g? I'm not trying to get you to spill the beans about particulars, just wondering what the potential savings range is liable to be.

Pauerman

M42,

Are you saying that you're getting pistons made that will be compatible with the Alusil cylinder walls?

In regards to connecting rod weight - isn't there a weight savings over stock when upgrading up to rods such as Carillo, Pauter etc..? Will your setup offer greater weight savings?

Also, piston speed - knife edging the crank and using a lightweight flywheel can help with this.... will your buildup include these upgrades or will it be based on a stock format?

If rod length (shorter) will be used to speed things up, doesn't rod angle become an issue once bigger hp/tq figures are made?

I don't mean to pry, so please answer only the questions that you can

Vic

TurboTim

We have the intake and the exhaust manifold required for the 16 valve turbo conversion along with all the other parts.

http://boards.rennlist.com/upload/968turbo001.jpg
http://boards.rennlist.com/upload/968turbointake001.jpg
http://boards.rennlist.com/upload/968header001.jpg

m42racer

To answer these questions, I have started another post, so that the oringinal post can be addressed.