Main girdle swaps

[spyderdrifter]

I'm going to be looking at a 6 bolt short block on Friday, as a replacement on my Spyder since I spun a bearing and the 7 bolt is now a very effective paper weight. I've been thinking about this for a long time, and have never found an answer. Can the 7 bolt main girdle be put on the 6 bt in place of the mini girdle caps? If not, why? My last 2g had a 6 bolt, but I didn't have a 7 bolt main girdle to test it out.

 

[ronnievermilion]

NO for a few reason.

1. The 7 bolts use a thrust washer bearing and the 6 bolts do not.

2. 6 bolt rods are thicker then 7 bolt rods so things are not going to line up their either!

Get a Kiggly Racing main gridle. Main Girdle - Kiggly Racing Parts for DSM and EVO

and some ARP main studs and you will have a strong main!

 

[Black95awd]

I'm going to be looking at a 6 bolt short block on Friday, as a replacement on my Spyder since I spun a bearing and the 7 bolt is now a very effective paper weight. I've been thinking about this for a long time, and have never found an answer. Can the 7 bolt main girdle be put on the 6 bt in place of the mini girdle caps? If not, why? My last 2g had a 6 bolt, but I didn't have a 7 bolt main girdle to test it out.

Probably with some excessive machining it could fit, however it's not worth the dicking around to attempt. Kiggly or Magnus main girdle.

NO for a few reason.

1. The 7 bolts use a thrust washer bearing and the 6 bolts do not.
-6 bolt and 7 bolt both have thrust bearings (as do most engines) They need to be there to locate the crankshaft in the block. "Crankwalk" is really just a thrust bearing failure. What you are thinking is probably the late 98-99 and Evo style with the split thrust design that does use 5 identical main bearings with 2 separate washers for thrust while the 6 bolt thru early 98 blocks use a single piece thrust bearing.

2. 6 bolt rods are thicker then 7 bolt rods so things are not going to line up their either!
-Rods are not in question here, mains are. however IIRC the main journals are a little different.

Get a Kiggly Racing main gridle. Main Girdle - Kiggly Racing Parts for DSM and EVO
-I like this or the Magnus unit. Both reputable names.

and some ARP main studs and you will have a strong main!
-If you use ARP (or any other) main studs be sure to have your block align honed to be sure the torque on the studs did not distort your main bores.

Please see in red, not trying to flame you, just trying to keep facts straight.