View Poll Results: GTS crank is toast... Options?
Look for a 2nd hand GTS crank
9
24.32%
Buy new from Porsche
4
10.81%
Get a Moldex crank with GTS sizing
2
5.41%
Go for a 6.2ltr stroker
22
59.46%
Voters: 37. You may not vote on this poll
GTS crank is toast...
#17
Rennlist Member
Thread Starter
Cost of a new crank from Porsche - £4500 ($6750) in stock
Cost of a welded crank by Moldex - $375 2 weeks turnaround
Cost of a Porsche reconditioned crank £1850 ($2400) lead times unknown
Cost of a Moldex GTS crank drilled like a Chevy $2750 - 14 weeks lead time
All other bearings are good with no scratches. Looks like a welding job at the moment. Moldex claim that the crank should be as good as new? I dunno... At the end of the day, it is in his interest to sell me a new crank, but he said there was no need???
Cost of a welded crank by Moldex - $375 2 weeks turnaround
Cost of a Porsche reconditioned crank £1850 ($2400) lead times unknown
Cost of a Moldex GTS crank drilled like a Chevy $2750 - 14 weeks lead time
All other bearings are good with no scratches. Looks like a welding job at the moment. Moldex claim that the crank should be as good as new? I dunno... At the end of the day, it is in his interest to sell me a new crank, but he said there was no need???
#18
Archive Gatekeeper
Rennlist Member
Rennlist Member
Does yours look about like this?
#19
Cheburator
Assuming your crank damage is scoring on bearing and the crank passes a magnaflux type inspection, you should be able to have your crank repaired as is likely the Moldex "welded" option.
Be advised that 928 cranks are flame or induction hardened. With the welding of one lobe, most crank folks recommend gas nitriding the whole crank as a means to get the surface hardness on the repaired journal. With this method, all journal need pre heat treat preperation. I would make sure any quote from a crank repair shop / person includes a magnaflux inspection, repair and post repair heat treat.
As $0.02, I have a repaired, nitrided crank in my DD BMW M5 and it's gone 20K miles since repair and is working fine. Last year, I repaired a 928S4 crank using this same method.
Best wishes which ever way you go.
Assuming your crank damage is scoring on bearing and the crank passes a magnaflux type inspection, you should be able to have your crank repaired as is likely the Moldex "welded" option.
Be advised that 928 cranks are flame or induction hardened. With the welding of one lobe, most crank folks recommend gas nitriding the whole crank as a means to get the surface hardness on the repaired journal. With this method, all journal need pre heat treat preperation. I would make sure any quote from a crank repair shop / person includes a magnaflux inspection, repair and post repair heat treat.
As $0.02, I have a repaired, nitrided crank in my DD BMW M5 and it's gone 20K miles since repair and is working fine. Last year, I repaired a 928S4 crank using this same method.
Best wishes which ever way you go.
#20
Rennlist Member
Thread Starter
#23
Shameful Thread Killer
Rennlist Member
Rennlist Member
I've used welded cranks in air cooled VWs for years. The technology is good, if the person doing the work is skilled. As with anything else, it can be screwed up too.
Note the color heat treating changes on the journal throw. After the crank journal is built up, then it is machined, then heat treated again, and final machining it should be good as new. I was going to do this for my GT crank but I found a used one for pretty reasonable.
Note the color heat treating changes on the journal throw. After the crank journal is built up, then it is machined, then heat treated again, and final machining it should be good as new. I was going to do this for my GT crank but I found a used one for pretty reasonable.
#24
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Note that Moldex ALWAYS quotes 14 weeks.....always no matter how long it really takes. They do much custom work for Detroit and when Ford wants a crank......Ford gets one The Porsche crank gets set aside
#25
Addict
Rennlist Member
Rennlist Member
i have a gts crank but i'm honestly not sure what condition it's in. it's been sitting in my garage for the last 5 years. got it with a bunch of gts parts that i picked up from my mechanic. i would be happy to have it checked for you if you tell me what needs to be checked and where might be the best place to check it.
#26
Drifting
#28
Drifting
You would be much better off to get another used engine until you decide what to do with this one.
You could help this Rennlister out and get a engine at the same time
https://rennlist.com/forums/928-foru...ercharger.html
You could help this Rennlister out and get a engine at the same time
https://rennlist.com/forums/928-foru...ercharger.html
#29
Addict
Rennlist Member
Rennlist Member
The GTS engine was one of the last ever produced by Porsche - special pistons made by Kolbenschmidt with the oil holes drilled through, special sleeves made of alusil pressed into the block and 2R rods...
Any suggestions are welcome...
Moldex seems to be the way fwd, but I need to know the costs and the lead times...
TIA
Any suggestions are welcome...
Moldex seems to be the way fwd, but I need to know the costs and the lead times...
TIA
Buy a Porsche crank......!