Main Girdle on a 351w stroker

[BenBaron]

Hi all,

I need some advice on main girdles, will a 302 girdle fit a 351w? and do people think they are worth the money?

Also what about clearance for a stroker is there any issues there?

cheers
Ben

[blykins]

I don't think they will fit Ben. I can't really tell you why...but they always sell them separately. If you have a 2-bolt block, yes they most definitely worth the money. Supposedly, it gives the block more bottom end strength than a 4-bolt main block. If you can picture it in your mind, it makes a big torque box out of the bottom end by connecting all the main caps. The result is that you couldn't budge one main cap without deflecting the other 4. Very stout.

Most main girdles come clearanced for stroker rods. Mine did. I ordered one from Ford Performance Solutions....it's .400" 4340 steel....and unlike others, it includes the loop around the oil pump. Some that I have seen just cut this out altogether, or not even include the front cap. It also comes with ARP fasteners....I'd go with studs. From an engineering standpoint, studs are stronger, because they have no head....i.e. no place for stress concentrations to gather. All of the stress goes into tension on the stud itself.

You can get a good one ready to bolt on (including fasteners) for under $200.

[BenBaron]

Much appriciate the advice,
I already have arp studs, do they need to be longer than the normal ones or will they do?

cheers

Ben

[blykins]

They need to be longer...by almost 1/2" to clear the girdle....and then even longer if you plan to use a crank scraper or windage tray.

[Curt C.]

Whether you need it or not would depend on the power level / RPM limit. Most 351W street engines will live easily with 450 - 500 HP and RPM's below 6000 rpm. They look cool though

[BenBaron]

Thanx guys,

bugger about the arp studs Ive got, looks liek they will be going on ebay if I decide to go for a girdle then ....

anybody know what the product code is for the arp studs that I would need?

cheers

ben

[blykins]

You can order them straight from ARP by just giving them the length you need. I guess you could figure the length of the standard stud plus the thickness of the girdle plus the thickness of the nut.

If you don't have the girdle, the studs usually come with them.

[brainsboy]

One thing to consider is what year 351w block you have. a 1975 to 1990 block is going to need a girdle before a 1969 to 1973block. IMO to be safe I would use one on 69-73blocks if your over 500hp and use one on 75-90 blocks if over 400hp.

[blykins]

If it's not a 4-bolt main block.....I think I would just go ahead and bolt one on. $179 is cheap insurance compared to slinging a rod through the oil pan.

[Mr.Fixit]

Shop I worked in we built plenty of +500 HP windsors and waranteed them, and never had a bottom end failure*, and we never used a main cap girdle. 2-bolt blocks, ARP studs, 7000 rpm.

*that would have been prevented by a girdle