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12/17/07
BOLT BUT
You state ARP rod bolts are to be lubed with 30 weight motor oil, is this correct? Can - should - 30 weight be used in place of the assembly lube (#100-9902 for example) sold by ARP?
Chad Labno
Miami, Florida
The GMPP rods are engineered to have their fasteners torqued or stretched using oil, but that doesn't mean Chad's rods are designed for that purpose. I believe I stated that in the article. Here is what the article copy states (and if Chad is reading this, please re-read this paragraph):
"The folks from ARP fasteners point out that if the recommended tightening specifications are based on the use of a special lubricant, the use of motor oil or other non-specified lubricant will result in insufficient pre-load. Engine oil is a good hydraulic bearing material, but it is a poor extreme pressure lubricant. If it is used on bolts, the torque required would actually increase, due to galling which makes the surfaces rougher. Essentially, the torque must be increased to compensate for the added friction induced by the non-specified lube. On a side note here, the GMPP connecting rods shown in the accompany photos have fasteners (from ARP) that are designed to be torqued or stretched using 30 wt oil. The bottom line here is, be sure to check the type of lube mandated by the rod and/or fastener manufacturer before you start crank it down."
Take care man...
Wayne Scraba
IT’S WHO YOU KNOW...
I'm an old high school buddy of Ro McGonegal. We started drag racing at Dover Dragstrip in Wingdale, NY back in 1963-64!
Jeff Ryan
Bradbury, California
That’s your problem, Jeff. McGonegal’s hard to gauge. He might even invite you to his house in Flori-duh. OK, Ryan and I had a very nice catching up conversation, but he’s a hard-core Ford guy, never had a Chevy that I know of, so what can I can I really say about Mr. Ryan?
FAIR WEATHER FRIEND
Hello,
I have several questions about your article in which you install the new HT383E in the Chevy truck.
Allow me to refer to this quote:
[quote]After about 300 break-in miles, we put the truck on Hardcore’s chassis dyno. The results showed clear gains across the board, with more horsepower and torque to the tires, but they were admittedly a little lower than we expected. At the tires, the 4WD Chevy put down 206 horses and 270 lb-ft; 14 hp and 14 lb-ft more than the baseline figures recorded before the swap. [quote]
Even adjusted for a 25% loss through the drivetrain, these #'s are low. What gives? Does the HT383E have false figures advertised? Do I read this right? 14 HP and 14 Ft-lb increase over a stock (worn out) Vortec 350?
Has there been any follow up or conversations w/ GM regarding these results? Do you know of any contacts at GM who may have some technical comment on this data?
I am very interested in buying the HT383E. However I won't purchase it if the #'s are 20-30% mis-advertised.
Thank you for your help,
Marv Springer
Mesa, Arizona
Marv,
Certainly GM wouldn’t post false power and torque readings. Could have been a very bad atmospheric day. We suggest that it was conditions during that particular period that helped squash the power output. The writer is long gone and we aren’t allowed to give GM employees’ phone numbers. We’ve seen other tests on this engine where it performed considerably better. Maybe you should offer this to a GM forum and see what gives. We know this is a suck answer but it’s all we got.
