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Posted by: Randal Mar 22 2009, 10:16 PM

I have to send my computer to HP for repair so was cleaning out some files today.

I had forgot just how nice a proper engine can look, from the inside.

Posted by: SirAndy Mar 22 2009, 10:39 PM

They only look that nice once ...
Andy

Posted by: Randal Mar 22 2009, 10:42 PM

Oh, but what a great learning process.

Posted by: grantsfo Mar 24 2009, 02:47 PM

Like like the simplicity. Thats a great motor. Glad the top end issues have been sorted. Cant wait to hear that thing rev up to 7 grand!

Posted by: McMark Mar 24 2009, 09:00 PM

That crank is gorgeous!

Posted by: Randal Mar 24 2009, 09:08 PM

Only the crank Mark? See anything else special?

Posted by: Chris Hamilton Mar 24 2009, 09:42 PM

Does that mean I get to post mine?

Randal, are those pauter rods in your engine?

Posted by: Randal Mar 25 2009, 05:12 AM

They are SCAT rods Chris.

Posted by: grantsfo Mar 25 2009, 10:58 AM

Nice Chris, What are you building? Or has it already been built?

Posted by: Chris Hamilton Mar 25 2009, 08:03 PM

Thats the engine in cliff's 914:

http://hamiltonracing.net/photos/cliff914/santarosa/IMG_3767.JPG

It's a 2.0 rabbit-rods with what webcam calls "the ultimate street cam". Never used that cam before and I have to say for a car he's gotta drive every day it's just about perfect.

My engine is basically identical, but with a stock 914 cam, and this webcam has a lot more punch in the midrange, and the engine seems to rev a bit freer. We had the 6k chip in the rev limiter at santa rosa, but up to that it pulled nicely, whereas my car with the stock cam seemed to get kinda sluggish up to my rev limiter at 7k.

I'd love to see if someone in this area would be willing to strap his car to a dyno and see what it puts out, because it feels great.

Posted by: sww914 Mar 25 2009, 10:26 PM

One of the shops at Buttonwillow has a dyno that's not too expensive.
Chris, what's the advantage of Rabbit rods?

Posted by: J P Stein Mar 26 2009, 12:00 AM

Sometimes complex is mo better.


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Posted by: SirAndy Mar 26 2009, 12:39 AM

Sometimes not having to open the motor at all is even morer betterer ...




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Posted by: Chris Hamilton Mar 26 2009, 09:31 AM

That would be nice, I'm sure cliff would be up for it.

The rabbit rods fix the fact that the 914 didn't come with a very good rod-length ratio. The 914 engine doesn't "breathe" very well, and the increased rod-length ratio improves that.

If you want the physics explanation, you get that Work equals the dot product of the force and direction vectors.

W = F • d, which simplified for a 2-dimensional scenario becomes W = F * d * cos ( theta ). If you increase the rod length you decrease the change in angle caused by the sweep of the connecting rod and minimize the potential range of theta.

Steve, you've driven Cliff's car, right? This rod length change manifests itself in a bunch more bottom end power.

Posted by: Randal Mar 26 2009, 10:30 AM

It'd be fun to have those chains on a 4.... and overhead cams.

Posted by: J P Stein Mar 26 2009, 12:27 PM

Even better would be a five main bearing crank....just my .05.

Posted by: grantsfo Mar 26 2009, 01:31 PM

So are you increasing stroke with these rods? What size cylinders and pistons? What is stroke? Assuming you are increasing displacement and compression ratio too? It makes sense if you stroke a stock 2.0 that you would get more displacement and power.

Posted by: Chris Hamilton Mar 26 2009, 06:08 PM

Nah, rod length doesn't affect stroke, the offset of the crank journals is the only factor in determining stroke. We keep the compression low so it will run on pump gas, compression is basically the same as stock. Cylinders are iron 94mm.

Posted by: Joe Ricard Mar 26 2009, 07:35 PM

My 2098cc has Wasser Boxer rods. Longer as well, lighter and stonger with ARP equalivent rod bolts. on a lightened 71mm crank with type 1 journals 11lb flywheel the motor spins very fast. Longer duration at TDC makes more power
and will also screw you big time with an aggresive cam as the valve is opening faster than the piston is going down in the intake stroke. Well if you are using domed pistons.

Posted by: grantsfo Mar 27 2009, 08:43 AM

Oh assumed you were doing something differnt with crank. So just compression is being increased. What kind of compression? How long are these rods?

Posted by: Randal Mar 27 2009, 09:25 AM

Have you heard any recent progress on those guys in Europe doing the overhead cam 4?

Posted by: J P Stein Mar 28 2009, 08:43 AM

I dunno of which set of heads you're speaking.

I do know that every few years someone comes up with a set of 4 valve air cooled heads be they T-4 or 911 .......and then fades into the background noise.

Thus far, no one has made them work.....including Porsche. The issue has always been heat or, more accurately, cooling the heads. One could probably get them to work for something like drag racing, but it seems highly unlikely for anything else.

Posted by: Randal Mar 28 2009, 09:29 AM

Wasn't it these guys <www.bugat5speed.de > that were building an entire engine, or maybe someone else in Europe.

I saw some videos of either these guys or someone else in Europe running autox in a bug with an OVHD cam engine (very fast), but I will have to look for it again.

Posted by: sixnotfour Mar 28 2009, 01:50 PM

yummy


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Posted by: J P Stein Mar 28 2009, 02:07 PM

$weet.
$tout case.

Posted by: Randal Mar 30 2009, 07:08 PM

Where is ADV Performance?

Posted by: grantsfo Mar 31 2009, 11:57 AM

Appears to be in Germany. Based on fact that the company has a url reserved in Germany. Here is a blog on that motor, but it hasnt been updated since Feb 2008.

http://adv-performance.blogspot.com/

ADV-performance has an email address: info@ADV-Performance.de

Posted by: grantsfo Mar 31 2009, 04:59 PM

Woof Woof. Found him.

http://66.163.168.225/babelfish/translate_url_content?.intl=us&lp=de_en&trurl=http%3a%2f%2fwww.bug-talk.de%2fforum%2fviewtopic.php%3ft%3d14405%26sid%3d172337c487dd81b53d781dbf2011344b

If I read right thats a 2.5 liter with goal of 250 HP.

Posted by: Randal Apr 1 2009, 09:24 AM

Still looking for that site with the autox videos. Some really fast VW's with (I think) 4 cam engines. Somewhere in Europe.

Posted by: grantsfo Apr 1 2009, 10:47 AM

Search using "kaefer cup". Some of those cars use the crazy home built 4 cams.

http://www.youtube.com/watch?v=6NCnnbsXA-w

Posted by: Randal Apr 1 2009, 11:04 AM

Why thank you Grant. Great search there.

Here is one of the ones I was looking for:

http://www.youtube.com/watch?v=RASRVfQrxXY

Tough course to remember hey?

There is another one, that I found on a website that had this same car, except with a new engine, maybe the OVHD I'm thinking, on a course that had lot of building, kind of like Alameda. They were racing around these buildings on access roads. And the VW was very quick.

Posted by: Randal Apr 1 2009, 11:06 AM

Bingo: http://www.youtube.com/watch?v=CbTpTaODCfQ&NR=1

Looks like a fun course, except for all the stuff that you could hit spinnig out. I mean those curbs are dangerous and the trees!

web site: http://www.aichlseder.info/d_index.htm

Posted by: grantsfo Apr 1 2009, 02:04 PM

Oh my. These guys kick our butts on the T4 coolness factor. that car is over the top. Have to figure out how to get that tranny on a 914! That Bug is exactly what I'd want in a 914 with a T4.

Posted by: Randal Apr 2 2009, 05:32 PM

I've email the aichlseder guys to ask what they have developed.

Posted by: SirAndy Apr 3 2009, 10:10 AM

Keep us posted!

Posted by: McMark Apr 3 2009, 07:21 PM

I had some thoughts on OHC Type 4. Or more specifically, UHC (under head cam). The holes that the pushrod tubes run though gets cut off and a cam box goes in. I would still use rockers, just like the Porsche six. Camshaft would be replaced with a chain drive.

It's on my R&D list, behind the stock cable shifter setup and the bolt in boxster transmission swap.

Posted by: Randal Apr 4 2009, 11:07 AM

What a shifter that actually works, in all conditions? Oh boy I want one of those.

My lockout device works great to eliminate first or reverse shifts once you get going, but I'd prefer a cable shifter that did the same.

Hitting first from 4th (downsifting at high speed) is interesting, especially at Infineon going into 7 or 11.