[J Banning]

(I also posted this question on the "other" board)

I need some identification help here. I've got two cranks, and two complete sets of rods. I'm pretty sure that one set is from a 86-87 motor, the other set I'm not so sure about. Here goes...

Crank #1
- Pretty sure this is factory 86-87. Jives with info on gnttype.org
- Casting number - 877.
- Rolled fillets on rod & main journals.
- Number near 2nd main journal: GM9.
- .10/.10, needs to be cut.

Crank #2
- Casting number - 877.
- Rolled fillets on main journals ONLY.
- Number near 2nd main journal: GM7.
- Numbers near crank snout: 2, E25.
- .10/.10

Rod set #1
- Pretty sure this is factory 86-87. Jives with info on gnttype.org
- 2 dots on beam
- The numbers on the other side of beam: 3, 763
- Letters near rear main: D, N

Rod set #2
- I can't find any info on these rods other than 3 dot is not what came with 86-87 VIN 7 motor.
- 3 dots on beam
- The numbers on the other side of beam: 8, 873


How fast/how much HP can you make with the 877 cranks that only have the fillets on the mains? I've heard of people running 11's with some N/A cranks. How about this one in particluar?

How about the 3 dot rods? Aside from the end caps being larger on the 2 dot rods, I don't see any differences. Anyone have experience running these rods?

It sure would be nice if there was some more info online on these parts.

Thanks,
-Banning.


------------------
86 T-Type WH1
Wilmington, DE
GSCA# 4817
Web site: http://www.geocities.com/jamesbanning

11.80 @ 112.8mph w/1.57 60'

Mods:
PT51 turbo w/.63 housing, Stock intercooler, 009's, Maxeffort 16 position, ATR 3" DP w/external gate, ATR test pipe, DelTrans 200R4, Vigilante 9.5" single disk, Eaton posi, Hooiser QT Pro 28/11.50/15's

 

[Steve Wood]

according to this
http://www.gnttype.org/techarea/pictureguides/rods/rods.html

Three dots rods are older ones. The two dot rods with 763 on them are supposedly the best ones.

With regard to cranks, most of us would not use the non turbo cranks in anything we were going to run seriously. Each time we say this, tho, someone pops up and knows someone that has run tens on an n.a. crank.

I look at it as a couple of hundred dollars more as insurance against a blow up that might cost $3000. GM says the roll filleted cranks are much stronger and saw fit to put them into the turbo cars...probably figured it was good for warranty work and we were running 12-14# of boost in those days.

 

[J Banning]

Thanks for the reply Steve.

I have the factory turbo crank and rods, so I'm definately going to use them. I'm just trying to figure out what the other parts are and how far they can be reasonably pushed.

-Banning.

------------------
86 T-Type WH1
Wilmington, DE
GSCA# 4817
Web site: http://www.geocities.com/jamesbanning

11.80 @ 112.8mph w/1.57 60'

Mods:
PT51 turbo w/.63 housing, Stock intercooler, 009's, Maxeffort 16 position, ATR 3" DP w/external gate, ATR test pipe, DelTrans 200R4, Vigilante 9.5" single disk, Eaton posi, Hooiser QT Pro 28/11.50/15's

 

[Steve Wood]

As you know, some claim no problems with the na crank...I just don't think it is worth the gamble...

I wish I had had the foresight to buy a couple of the TA cross drilled cranks but...my hindsight is some of the best in the country!