DP935 engine what are they made of?

[ficke]

[QUOTE=voitureltd;9213085]

Originally Posted by faapgar

.Dp was actually a styling makeover.Any engine mods came from the Kremers.There was no in house engine service other than bolting on a big intercooler. (quote)

^^^^
I have heard similar stories.

Here is the build sheet from a Kremer. It was furnished to an appraisal company for insurance coverage years ago. I recently contacted Kremer GMBH and sent a copy of this build sheet for additional details of the build for more info however I was told both Manfred and Irwin Kremer are no longer with them. As a result no further details are available.

Thanks for verifying 'Faapgar', It is neat to get info. on these tuners of the day. Although your car had some mild tuning to the heads, mods, in the way of porting and polishing and some people consider cams not a "bolt on" mod.
But that paper does show the basic stock Porsche 930 long block is what Kremer used with bolt on stuff. No twin plugging, no bigger P&C's, no bigger valves, no Carrilio rods are even splitting the case at all, pretty much stock 930 engine with bolt on stuff.
I Learn stuff every day.

[unclebilly]

I have a 77 911 Carrera 3.0 that had a DP935 body kit.

[voitureltd]

Originally Posted by sundevil64

Wow 3.2 sec for 0-60mph! That is wicked fast in any book! That would have been fun to ride I. That car with Mr. Andretti.

I think the 345 tires had something to do with it. I had to replace the 2nd gear syncros with under 10K miles on it. A neighbor/friend in New Orleans said the second owner Al Copeland ( founder of Popeyes Chicken chain) did burnouts up the street for them once in awhile, when he first got it. in 1987-88.

[voitureltd]

^^^^^^
Photos of the Porsche Kremer street 935 K2 in the before posted build sheet. Still iconic to show and fun drive a 935 style Porsche on the street. Even today you gotta have a pretty serious production machine to keep up with this 30 year old from Kremer.

[930cabman]

Originally Posted by sundevil64

wow 3.2 sec for 0-60mph! That is wicked fast in any book! That would have been fun to ride i. That car with mr. Andretti.

+1

To pull 192 mph with a 4.1 axle ratio, now thats some powa and some rpms. I guess thats why Mario was the owner. What I would give to have ridden with him in this baby back in the day.

Great find and this is a piece of history my friends.

[ficke]

Originally Posted by 930cabman

+1

To pull 192 mph with a 4.1 axle ratio, now thats some powa and some rpms. I guess thats why Mario was the owner. What I would give to have ridden with him in this baby back in the day.

Great find and this is a piece of history my friends.

Impressive indeed, about 7,000 RPM is needed to achieve 190 MPH with 410 gear ratio, and on a factory stock lower end!

Another Kremer 935 'look' car reconfirming again the bolt on hot rodding of the Kremer street cars with no internal up grades of the engine, This car did not even get different cams or the head porting.
1984 Porsche 935 Kremer G5 Street 2. One of Five!

[Pesch]

I see that the subject woke up some memories, nice to see stories coming along...
From the different feedback, it seems like DP or Kremer just put bolts-on up on most of the engines and some get some group B cams...
So it looks like they just removed the boost fuel cut off and the rev limiter to let the owners play to the limit. Reliability was not a concern as long as you could smoke any other car around even if it's only for few thousands of kilometers...

I'll know a bit more about my engine soon, the car has an epic story that I'll go more in details on a dedicated post.
But as I understood, the engine is completely overhauled, not even broken in...
Mechanic didn't went further than installing back the engine in.
Fuel head and ignition to be sorted out.
Calling the mech in a while to know if he noticed anything special.

[Pesch]

So mechanic overhauled engine around 7 years ago but didn't noticed anything special in the internals.
He doesn't remember much about what parts he put in, I'm then not sure about head stud or rod bolts...
Not sure what to do... try to start it and break it in or split the case and check all that again...

[ficke]

Originally Posted by Pesch

So mechanic overhauled engine around 7 years ago but didn't noticed anything special in the internals.
He doesn't remember much about what parts he put in, I'm then not sure about head stud or rod bolts...
Not sure what to do... try to start it and break it in or split the case and check all that again...

That is tough, for instance HP., pressure from the burning gas, does not travel through the rod bolts but RPM does put the strain on them, so do you limit the RPM's of the engine to be safe, when maybe you had ARP rod bolts all along? Or what else??
I think I would vote to split the case and know what you have. Other wise you will always question your engine limits.

[Pesch]

Better safe than sorry, yes.
I'll inspect all with borescope 1st, that will give me better idea.
I'm a bit worried about the dilavar head stud as the car looks to have been stored in a no so dry environment.

As per the mechanic, one camshaft was broken and they put a euro spec camshaft instead of Us one.
Knowing that there were no such thing as a US 930 in 1982, I don't know what was the previous camshaft (maybe group B).

He however tells a lot of stories as as per his saying, the previous owner has been once Israeli jeweler once Iranian auto body man....

Looks that I'm not going to be able to trace further the history of the car...

[Pesch]

A bit of update, looks that not everybody have the same notion of engine rebuild.
Engine looks that it has never been fired, pistons are clean but not new, valves have been ground etc.
What surprised me is that there was still some thick dirty oil in the sump plate recess (engine is otherwise dry.

However, it looks like DP were opening the engines and putting what's necessary to raise the RPM limit.
I've found some good looking light valve retainer I've never seen before, a friend of mine told me that he saw some similar ones on a RSR engine.



Unfortunately, mechanics that "overhauled" the engine changed the camshaft as one was supposedly broken (I would think more of worn lobe).

[Porsche 935]

Looks like the ones I bought from cmw racing years ago.

[faapgar]

CMW holey retainers for sure.Fred

[Pesch]

Thanks for the info on the retainers.
They are somehow rough on the holes edges, I'm going to deburr them a bit better.
Car is supposed to have been build by DP in 1985.
Would you think the retainer were available at the time?

[faapgar]

They were available then from CMW but if it was not made in Germany Kremer Brothers probably would not use it.Fred

[faapgar]

Also Happy 917 day as it is 9\17\16 for the 16 cylinder beast that was built but not raced.Fred

[81Kremer930]

We restored a 1981 Kremer 930 a few years ago, not really knowing anything about Kremer/DP etc, I did most of my research here, online, and by phone. I spoke to a couple of fellows at Kremer in 2012, and all they could do was confirm that my car was one of their builds, but that each car was done upon customer request, and they were almost all unique. My car has the 935 boost controller, k27 turbo, group b cams, but came with stock intercooler, exhaust, etc.

Upon further inspection of the car, it had three broken headstuds, bad turbo charger, two pistons had broken rings, and numerous oil leaks. A full teardown, and rebuild was in order. I had to have two studs removed with an edm(electrical discharge machine), and confirmed that the case, heads, and towers are all made of aluminum. All the heads are ported and polished, as well as the intake manifold. My car is flame-ringed, which is not all that unusual as well. The factory bottom ends of these cars are actually quite good/beefy stock. 400whp isn't out of the question with free flowing exhaust and intercooler, ball bearing turbo, and correct cis/boost adjustments.