Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Porsche 911 Technical Forum (http://forums.pelicanparts.com/porsche-911-technical-forum/)
-   -   What kind of engine do I have? (http://forums.pelicanparts.com/porsche-911-technical-forum/529135-what-kind-engine-do-i-have.html)

daepp 03-04-2010 03:26 PM

I had no idea there were 4-cam 8's.

I have been mesmerized about the 4-cams for years. I can't believe that there are still quite a few people/companies that still know how to rebuild them! Thank God (and thank Fuhrman!)

jkarolyi 03-04-2010 03:38 PM

*subscribed* Great commentary as usual Grady!

Nine17 03-04-2010 03:43 PM

Grady is the only one one who "got" the Forbidden Planet reference... I hope that there really is a motor out there and that it winds up in hands which can appreciate its Werner von Braun (or maybe Rube Goldberg) complexity...

sc_rufctr 03-04-2010 04:05 PM

I'm getting very excited about this thread...

Maybe the thread of the year... Or decade!

More pictures please please please... :)

sc_rufctr 03-04-2010 04:09 PM

Quote:

Originally Posted by Grady Clay (Post 5218129)
...

The issue was complexity vs. simplicity.

Inside the 692 (and the others) are 18 gears. There are eight bevel-gear
pairs (similar to a transmission ring & pinion) that must be first adjusted
for backlash and contact pattern. Only then can you start adjusting to get
the eight cams individually in time. Some of the timing adjustments require
disturbing the backlash and contact pattern settings...

Has anyone written a DYI on this? ;-)

It sounds like about 8 hours work for a pro! :eek:

Rrrockhound 03-04-2010 04:26 PM

Quote:

Originally Posted by sc_rufctr (Post 5218218)
Has anyone written a DYI on this? ;-)

It sounds like about 8 hours work for a pro! :eek:

According to Dean Batchelor's Buyer's Guide (quoting Fuhrmann, page 60, 2nd edition):

"These first four-cam engines took a skilled man 120 hours to assemble a complete engine, and the timing alone could take eight hours -- sometimes fifteen if tolerances weren't just right."

Grady Clay 03-04-2010 04:27 PM

Quote:

Originally Posted by sc_rufctr (Post 5218218)
It sounds like about 8 hours work for a pro! :eek:

More like 40-60 hours if you have a lot of experience, new cam drive bearings and all the shims.
Then there is the 20-30 to finally assemble the engine, re-checking everything.
That is on top of a normal rebuild and valve job.

Best,
Grady

sc_rufctr 03-04-2010 04:35 PM

Quote:

Originally Posted by Grady Clay (Post 5218252)
More like 40-60 hours if you have a lot of experience, new cam drive bearings and all the shims.
Then there is the 20-30 to finally assemble the engine, re-checking everything.
That is on top of a normal rebuild and valve job.

Best,
Grady

I'm feeling very humble right now... (in a good way) ;)

pplkook 03-04-2010 04:46 PM

How many Abarth GTs were produced? How many were brought to the US?

All healthy and realistic skepticism aside, just wrap your head around the potentially long odds of some one ending up with an Abarth GT engine and not know what it is, especially in the sates, and especially in Colorado (so close to Grady and he doesn't know about it)....

If this is true, I feel sorry for you Uber, you should have bought PowerBall lottery tickets and with your luck you would have won! Rather than burn it up on a 100k Porsche engine!!

The only way this could get better is if Uber really needs the money for some heart wrenching personal reason, and lucking into this motor changes his life.

If Uber doesn't contact Grady directly/privately with all the information that has been asked in the next day or so - understandable to be vague as to not get barraged by hacks, just like lottery winners - then I say it was a fun ride, but alas another hoax.

-Jack

Hotwatermusic 03-04-2010 04:57 PM

Quote:

Originally Posted by Rrrockhound (Post 5218251)
According to Dean Batchelor's Buyer's Guide (quoting Fuhrmann, page 60, 2nd edition):

"These first four-cam engines took a skilled man 120 hours to assemble a complete engine, and the timing alone could take eight hours -- sometimes fifteen if tolerances weren't just right."

Damn all that work for 135Hp?! A 1960 Ferrari 250 had about 275. But that's a V12 for ya.

Grady Clay 03-04-2010 05:36 PM

Jack,

It may very well turn out that I do know the engine. Forty years ago, I probably knew them
all. At least I may have raced against it. It is even possible I owned it at one time. I think
I owned 38 but it may have been into the 40s. Unfortunately I don’t have records.

Clearly it isn’t just ‘out of an Abarth Carrera’ as it is configured for mid-engine as in a
Spyder. The Abarth Carreras were all rear-engine cars, built on 356B(T5) Porsche chassis.

Of course it is possibly out of an Abarth originally, although there were more 692/3A
engines (50+) than there were Abarth Carreras (20).

From what I can see, uber’s pictures and posts says it has some serious updates.
Those Weber 46IDAs were ’64 904 and the spacers were ’65 904 ‘improvements’.
I’ll bet it has an interesting history. It certainly has had a long one.

Once we get more information, I’ll email Jurgen Barth and see if he can pester someone
at the Factory to trace the engine from that direction.

Best,
Grady

sc_rufctr 03-04-2010 05:43 PM

Quote:

Originally Posted by Grady Clay (Post 5218370)
....

Once we get more information, I’ll email Jurgen Barth and see if he can pester someone
at the Factory to trace the engine from that direction.

Best,
Grady

An email address for Jurgen Barth!!! :eek: Does he check it daily?

Care to share?... ;) haha

Grady Clay 03-04-2010 05:59 PM

"Does he check it daily?"

Certainally not for MY emails.
I do owe him some 904 numbers.

Best,
Grady

FrinkFrog 03-04-2010 06:24 PM

Grady, I just have to say you are the best.

Kirk

Nine17 03-04-2010 06:45 PM

A good case has been made that wherever that motor is today, forty-five years ago it was in a 904 Carrera GTS. As for Barth, I've met him; we have mutual friends. He opens e-mail from knowledgable people like Mr. Clay who are keeping the flame alive.

Nostril Cheese 03-04-2010 08:05 PM

Grady,

Are the flywheels on the ends of the cams simply to balance cam rotation or do they drive any ancillary components? If I understand correctly, the early engines ran the distributors off the ends of the cams?

Flieger 03-04-2010 08:17 PM

The early engines drove the distributors on the ends of the cams but they found there was too much vibration there which was messing up ignition timing. That is why they switched to the V drive off the crankshaft. This vibration (torsional, I believe) was found to be excessive for proper valve timing as well so the flywheels were fitted to smooth the running.

ths911 03-04-2010 09:09 PM

if nothing else, this has been a great engine history lesson.

thanks.

HarryD 03-04-2010 09:18 PM

Wow, some story. At this point I would hope that Uber and Grady have some private conversation and hopefully a meet up. I just want to see the end report.

Grady Clay 03-05-2010 05:45 AM

It is the real deal as advertised.

uber, myself and Bill Doyle corresponded yesterday.

There will be more information coming although probably not as fast as the Forum would like.

We all should be embarrassed by the reception given uber. Healthy skepticism is OK, nourish behavior and off-color references are not.



I will continue with 692 information. This is a great subject to understand the progression of 4-cam engines. As we saw above, the 692 was both a progression and simultaneously used with the 547.

The 692 lead directly to the Carrera 2, Carrera 2 GT and the 904 2-liter 587s.

The 8-cylinders are of parallel interest. They were for F1, the 908 and one even ended up in a Factory 914 in the mid ‘70s.

Please add more information and images.

Best,
Grady


All times are GMT -8. The time now is 03:33 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.