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Rob's GTS engine pull

 
Old 09-30-2015, 08:36 PM
  #196  
Rob Edwards
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Yes, Mark, one could do all of that, but if you stopped to read any of my reasoning for repairing the original block, you would recognize that anything other than using the original block is not the goal here.
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Old 10-01-2015, 06:32 AM
  #197  
Strosek Ultra
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Originally Posted by Rob Edwards View Post
Hi Ake- Actually we're going to sleeve all 8 cylinders, run eight new aluminum pistons that match all GTS dimensions (except weight) with stock R2 rods, the repaired stock crank and cams, and Greg's latest take on breather improvements. Goal is to have a correct-looking GTS motor without the oil consumption or pretzel rods, so I can make the GTS 'whole' at some point.

Am beginning to get bad ideas about a stroker transplant into an early body where I'm unencumbered by wanting to still be able to return everything to stock. Modding a 5-speed GTS just doesn't seem like such a good idea anymore, and I need a new project.

In the meantime I spent the weekend measuring Anderson's pile of cams, so made some progress on the new Zombie motor too.
Well Rob, sleeving all eight cylinders sounds much better to me but more expensive for you. For my two engines I have been told to bore and Nicasil or to put in steel sleeves Nicasiled but I am going to go the good old way with CI sleeves mostly because I can do the complete work in house.
In order to be able to put up the engine block in the mill for machining I am in the process of fabricating a jig similar as shown in the picture. The knee mill I have is very sturdy but not high enough for the machining of a V8 block tipped on the side. Have acquired a riser block which will rise the top of the machine by eight inches. http://www.ryanbrownracing.com/Bill_Jones_Page_10.html
I have also made a large boring bar able to bore well over six inches in diameter. The micrometer carbide tool holder is a precision instrument made in Germany and quite expensive.
Love to see the results of your measurements of the Anderson┤s pile of cams.
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Old 10-01-2015, 06:40 AM
  #198  
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Originally Posted by Strosek Ultra View Post
Fred, I was going to put a GTS crank into a S4 block but as you remember I sold the crank to Houssam in Saudi Arabia. Now it will be a 3.75" stroker crank with 104mm pistons under some special ported 2V heads. I have not checked very carefully but if there is an interference between the the rotating assembly and the block it cannot be very much, not more than it can be cleaned out using the die grinder.
The major design fault with the 928 engine block is that the oil drains also have to act as pressure equalizer between the crankcase and the heads. Best is to add some chimneys inside the V for the pressure equalization making the oil drains to work as they are intended to do. Check out the Ford Modular engine block which is very well designed in this respect.
┼ke
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┼ke

Interesting how the kind of things that have been talked about and implemented on custom 928's are implemented in this Ford motor that looks very nicely put together. Interesting how they are close to 100bhp/litre and the windage tray is integral with the sump. It will be interesting to see if Rob goes for a totally stock build or seeks to implement some of the corrective measures that you mention.

The thing that has puzzled me for some years now is exactly what Porsche were aware of when they designed and built our motors. I cannot believe these problems were not known of. Couple that with weak R1 rods, pistons with suspect oil draining capabilities, inability to drain oil in high G corners/high revs etc etc. Too many motors have [apparently] grenaded on the very autobahns they were designed for.

Not sure I would be bound by compliance to stock specs if my motor was at this stage of rebuild but I can understand the logic.

Rob's a pretty savvy chap and doubtless he will make the right decisions. If he does put this motor back in his GTS I am sure I could be persuaded to take his stroker motor off his hands to clear some space in his garage- indeed I would probably do so free of charge!

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Old 10-01-2015, 07:08 AM
  #199  
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The riser block weight 60 Kgs or 133 lbs, nothing you throw in under the top if the machine without effort.
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Old 10-01-2015, 07:54 AM
  #200  
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Originally Posted by FredR View Post
┼ke

Interesting how the kind of things that have been talked about and implemented on custom 928's are implemented in this Ford motor that looks very nicely put together. Interesting how they are close to 100bhp/litre and the windage tray is integral with the sump. It will be interesting to see if Rob goes for a totally stock build or seeks to implement some of the corrective measures that you mention.

The thing that has puzzled me for some years now is exactly what Porsche were aware of when they designed and built our motors. I cannot believe these problems were not known of. Couple that with weak R1 rods, pistons with suspect oil draining capabilities, inability to drain oil in high G corners/high revs etc etc. Too many motors have [apparently] grenaded on the very autobahns they were designed for.

Not sure I would be bound by compliance to stock specs if my motor was at this stage of rebuild but I can understand the logic.

Rob's a pretty savvy chap and doubtless he will make the right decisions. If he does put this motor back in his GTS I am sure I could be persuaded to take his stroker motor off his hands to clear some space in his garage- indeed I would probably do so free of charge!

Rgds

Fred
Fred, the old 2V engines have no ventilation at the heads only at the crankcase. Think the problems started with the 4V engines having ventilation at both the crankcase and the valve covers. Seems the crankcase ventilation at certain conditions gets overwhelmed making the high pressure gases go up the oil drains preventing the oil drain to function properly and the heads will get filled with oil, well you know the problem.
I have checked out more engines with cam belt drive (chain drive engines do have a large cavity where the chain is running also acting as a pressure equalizer) and I have found devices (chimney) for pressure equalization like the large tube going from the crankcase to the head on this BMW engine.
Yes, from pictures I can see Rob┤s garage is pretty much full with all kind of stuff. It must be a relief for him if you can help him clear some of the stuff out like a large engine.
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Old 10-01-2015, 03:01 PM
  #201  
mark kibort
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Originally Posted by Rob Edwards View Post
Yes, Mark, one could do all of that, but if you stopped to read any of my reasoning for repairing the original block, you would recognize that anything other than using the original block is not the goal here.
yes, more than understood. and i respect the desire to preserve the OE portion of the car, for the most part. Just wondering if anyone has used the S4 block and different piston packages to fix the inherent oil burning issues.
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