mustangman36578

what is the difference between 6 bolt and 8 bolt crankshafts? is the 8 bolt a lot stronger than a 6 bolt? im rebuilding a cobra motor and im looking to get around 400 hp would it be safe to use the 6 bolt crank from my GT motor or should i invest in an 8 bolt cobra crank?

im building this engine on a budget so any where i can sve money helps

uberstang1

The cobra cranks are forged.

redbullitt

if you are justgoing for 400 the 6 boltshould be fine. Any more power though, and it would be a good idea to go ahead and do it. Its one of those things you may as well do while you are in there. Also, i think forged cranks come is 6 bolt too. get ahold of a cobra crank if you wanna save money, no need to go aftermarket or priceyfor what you are shooting for.

Eagle2000GT

The engine builders I've talked to say only the '03/04 Cobra motorsare the only ones withforged cranks (as well as rods and pistons). Other Cobra motors have cast cranks. But then again they assure me that he Mach 1 with a manual transmission has a forged crank and a Mach 1 with an automatic has a cast crank. To me, that defies all logic.

Mark99GT

All 96+ cobras have a forged crank. They're correct about the Mach's...

oxfordgt

Find a new engine builder.
All cobras have 8 bolt forged cranks. 96-00 windsor GTshave 8 bolt cast cranks and 01-04 romeo GTs have 6 bolt cast cranks. Cast cranks are good up to 650 hp reguardless of bolt count and the cobra cranks which only came in 8 bolt are good for 1000+. I'm not positive but I'm pretty sure that any of the 90s 4v motors had forged cranks ie Mark VIII

lizzyfan

Crank is the last to go anyway!

FDNYBullitt

If you are 100% sure that you are never gonna go for that 600HP mark( alot of guys say they won't but once the bug bites you ???) then the cast crank will be fine, and its a bit lighter.As stated above the bolt count has nothing to do with it. I would get a set of ARP main studs though, just a little insurance, good luck.