A few of us racers are building Porsche 944 engines this winter and have had some minor machine work done to the crankshafts...The shop that did the work said that they do not want us to use synthetics because they foam and that the best oil is Pennzoil Racing 25w50. Now I have been using both Redline and Brad Penn oils and have had terrific UOA's and am not about to switch but I'd like to get the boards response to these statements and opinions from the machinist.
Engine machine shop oil recommendations??
- Thread starter oliver88
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Well we all know mechanics and machinist's are Lubrication engineers and all around experts! I know some probably are but very few and far between.
I would use the best synthetic oil I can get my hands on that is in the viscosity range for your engine. Which I would assume is x-40 or x-50wt.
Foaming IMO is more a formulation issue. Regardless of it being syn or dino.
I would use the best synthetic oil I can get my hands on that is in the viscosity range for your engine. Which I would assume is x-40 or x-50wt.
Foaming IMO is more a formulation issue. Regardless of it being syn or dino.
If I took advice from my machinist I would be running a cheap 5w-30 dino in my turbo v-8
Some of these guys know their stuff but many are old school and no little to nothing about oil. Synthetics foaming??? Redline and many of the other syns have zero issue with foaming so not sure where they are getting that info. Its wrong.
Use what the engine is designed for i have a machine shop and tell everyone to use the oil that the original engine builder recommends
25w50 is on the heavy side.. Some of those older engines like the thicker stuff but there are lighter alternatives.. Im one of the ones that like a thinner oil unless there is a problem with leaks, bearing noise,or burning oil
25w50 is on the heavy side.. Some of those older engines like the thicker stuff but there are lighter alternatives.. Im one of the ones that like a thinner oil unless there is a problem with leaks, bearing noise,or burning oil
Originally Posted By: crazyoildude
Use what the engine is designed for i have a machine shop and tell everyone to use the oil that the original engine builder recommends
25w50 is on the heavy side.. Some of those older engines like the thicker stuff but there are lighter alternatives.. Im one of the ones that like a thinner oil unless there is a problem with leaks, bearing noise,or burning oil
That's generally good advice, unless the machine shop also is convinced they know more about clearances than the factory and is building engines with big clearances. I would be suspicious of the shop that gave the bogus oil advice and at the least find out what clearances they run in their engines.
Use what the engine is designed for i have a machine shop and tell everyone to use the oil that the original engine builder recommends
25w50 is on the heavy side.. Some of those older engines like the thicker stuff but there are lighter alternatives.. Im one of the ones that like a thinner oil unless there is a problem with leaks, bearing noise,or burning oil
That's generally good advice, unless the machine shop also is convinced they know more about clearances than the factory and is building engines with big clearances. I would be suspicious of the shop that gave the bogus oil advice and at the least find out what clearances they run in their engines.
I don't know if it is the right weight for your application, but for racing applications the Pennzoil Racing 25W-50 is a very good product.
Ask them for their sources and reasons for this strong statement.
Not just their opinion, but the reason why.
You could help them, after the initial pride and resistance wears off.
Not just their opinion, but the reason why.
You could help them, after the initial pride and resistance wears off.
Originally Posted By: oliver88
Johnny, I have not seen much on the 25w50 Pennzoil...do you have any info??
http://www.epc.shell.com/Docs/GPCDOC_X_cbe_24855_key_140003211539_20090625220_8.pdf
Johnny, I have not seen much on the 25w50 Pennzoil...do you have any info??
http://www.epc.shell.com/Docs/GPCDOC_X_cbe_24855_key_140003211539_20090625220_8.pdf
if they were setting those cranks to a big clearance then that would explain the recommendation.
Make sure thr fillet is proper per Porsche and well done. Magnuflux for cracks, then nitride and the rest is not an issue...... I would use Brad Penn since you have them on hand for their Break-In SAE 30. After the initial run in as long as non-solid assembly lubes where used like Redline's assembly lube I would make sure the timing was set properly and then take her on the road. I would do some 2 and third gear WOT pulls up to the speed limit for the road you are on then let the engine break to 1/2 that speed and re-do that about 13 times.......I would hit the high way to get the temp. stable and and vary the RPM's from low to high then back to the garage for an oil change.
This is why I use things like Redline Assembly lube and stoped useing Moly EP grease. Moly EP grease has solids in it that plug up the filter and require you to change the oil and filter after hte 20 minute run in which is a waste of good break in oil.
Oh and even with say redline assembly lube still prime the engine if you can. Also always use assbly lube on the oil pump. I have sen a lot of scored pumps in my life time.
Oh and for those that do not understand why engine breaking is almost a must for good break-in it lifts the rings up out of their seat and allows them to move.It ensures that when you get on it again you have good ring seal at all times dureing the WOT and the engine braking....It helps to properly seat the rings faster.This prevents high speed glazing from ever becomeing an issue dureing break-in. THis is especialy true withhigh tension rings but even under cut rings ie low tension can benifit from it.
This is why I use things like Redline Assembly lube and stoped useing Moly EP grease. Moly EP grease has solids in it that plug up the filter and require you to change the oil and filter after hte 20 minute run in which is a waste of good break in oil.
Oh and even with say redline assembly lube still prime the engine if you can. Also always use assbly lube on the oil pump. I have sen a lot of scored pumps in my life time.
Oh and for those that do not understand why engine breaking is almost a must for good break-in it lifts the rings up out of their seat and allows them to move.It ensures that when you get on it again you have good ring seal at all times dureing the WOT and the engine braking....It helps to properly seat the rings faster.This prevents high speed glazing from ever becomeing an issue dureing break-in. THis is especialy true withhigh tension rings but even under cut rings ie low tension can benifit from it.
Their is no reason to run a Porsche 944 on 20W50 at all! IN fact Redline 5W30 or 10W40 would be more then good. If I recall properly the Redline 5W30 has an HTHS of 3.8 so just under 4 and if you where going to race this around a track then I would go Redline 10W40 which has a higher HTHS then any dino 20W50 on this planet! If this was an air cooled Porsche 911 Turbo I could see the 20W50 recomendation but for a 944 it makes no sense at all. I mean even the old VW's often run 20W50 but that is true of almost all old school air cooled engines due to lose clearances when cold compared to when hot. Oil consumption is not an issue in the 944 like it was in the older 911 Turbo engines. Today few people would run 20W50 dino int heir modern Porsche 911 Turbo and would think you made to consider it with such great synthetics like Redline 5W50,M1 15W50-non-EP version, and all the great 5W40 and 0W40 products.
In fact that 944 would probably do well on M1 0W40 after the intial break-in.
In fact that 944 would probably do well on M1 0W40 after the intial break-in.
I certainly would not feel like I was running too thin of an oil if I dropped down a grade while using synthetic. I can attest to the moly plugging things up.
We rebuild them to oem like new.. Sometimes you get a real oldie and then i sometimes tell the customer to use a different oil.. Some real old ones used to recommend 30 wt. i say in most cases use a 10w30 because back in the 50's and 60's they did not have the great oils we have today but for the most part i use what the car manufacturer calls for when the engine was new..
Some high performance shops want the customer to use a very thick oil others want the thin stuff.. Who is rite and who is wrong is questionable we build them to stock and do very little custom high performance engines..
I think if it were mine i would use a 5w40 syn maybe a 0w40 in the winter.. 25w50 is heavy...
Some high performance shops want the customer to use a very thick oil others want the thin stuff.. Who is rite and who is wrong is questionable we build them to stock and do very little custom high performance engines..
I think if it were mine i would use a 5w40 syn maybe a 0w40 in the winter.. 25w50 is heavy...
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If you just want to putter around or even rapid hwy cruising and are living in a cold climate, then go for a low visc oil. But for any old flat tappet motor especially one that sees hot weather, lots of traffic or any track work you're crazy to use a low W synthetic oil. Many many cases of spun bearings have been on cars which have blindly been using e.g. M1 0w/40. Not to mention all the premature engine wear.
Lots of bench experts on this site who I guess don't have experience with Porsche flat tappet motors?
Look to this thread for in the field experience. Prepare to be educated by pros like Charles Navarro and Steve Weiner with true field experience:
http://forums.pelicanparts.com/porsche-9...j4-sm-oils.html
Lots of bench experts on this site who I guess don't have experience with Porsche flat tappet motors?
Look to this thread for in the field experience. Prepare to be educated by pros like Charles Navarro and Steve Weiner with true field experience:
http://forums.pelicanparts.com/porsche-9...j4-sm-oils.html
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Originally Posted By: SHARKYTOOTH
If you just want to putter around or even rapid hwy cruising and are living in a cold climate, then go for a low visc oil. But for any old flat tappet motor especially one that sees hot weather, lots of traffic or any track work you're crazy to use a low W synthetic oil. Many many cases of spun bearings have been on cars which have blindly been using e.g. M1 0w/40. Not to mention all the premature engine wear.
Lots of bench experts on this site who I guess don't have experience with Porsche flat tappet motors?
Look to this thread for in the field experience. Prepare to be educated by pros like Charles Navarro and Steve Weiner with true field experience:
http://forums.pelicanparts.com/porsche-9...j4-sm-oils.html
You are very new to this site so statements like "Prepare to be educated" or "crazy" or "blindly using" or "bench experts on this site" may not set well with many members at BITOG. Just some advise. Welcome to BITOG!!
If you just want to putter around or even rapid hwy cruising and are living in a cold climate, then go for a low visc oil. But for any old flat tappet motor especially one that sees hot weather, lots of traffic or any track work you're crazy to use a low W synthetic oil. Many many cases of spun bearings have been on cars which have blindly been using e.g. M1 0w/40. Not to mention all the premature engine wear.
Lots of bench experts on this site who I guess don't have experience with Porsche flat tappet motors?
Look to this thread for in the field experience. Prepare to be educated by pros like Charles Navarro and Steve Weiner with true field experience:
http://forums.pelicanparts.com/porsche-9...j4-sm-oils.html
You are very new to this site so statements like "Prepare to be educated" or "crazy" or "blindly using" or "bench experts on this site" may not set well with many members at BITOG. Just some advise. Welcome to BITOG!!
I think your statement of excellent UOAs makes an excellent statement. Unless you have opened up the crankshaft to bearing clearances, use the oil that gave you the good UOAs. JMO. Ed
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