Cross bolted main cap questions

Posted By: '72CudaRacer

Cross bolted main cap questions - 01/31/14 04:48 AM

I am freshing up a friends 540 ci RB engine that has a after market Mopar block with cross bolted main caps, like a Hemi does. I've never done one of these and I need to know the proper procedure for torqueing the main caps. I'm guessing that I need to install all bolts to a light torque, then torque the main studs completely, then torque the side bolts last? If this is correct, what should the torque values be? I'm assuming the side bolts need some sort of sealer on the the washer to block surface to prevent oil leaks. What works best there?
Thanks,

Brian

Posted By: moparman89

Re: Cross bolted main cap questions - 01/31/14 04:57 AM

25 ft/lb on the cross bolts, never used a sealer. The cross bolt really have no effect on the roundness/diameter of the housing bore.

Posted By: Cab_Burge

Re: Cross bolted main cap questions - 01/31/14 05:44 AM

I've never done a Mopar brand Wedge four bolt main block but I would probaly use the same specs on the side bolts as the stock street Hemi, as long as there 3/8 diameter also

Best bet would be to call the Mopar Tech line and see, if there still open and answering the phone lines

if they have the recommended specs and procedures

I've done a couple of the World Wedge and one hemi block and 45 ft lbs comnes into my mind for the side bolts torque specs, but there not the Mopar brand either

Posted By: WadeMetzinger

Re: Cross bolted main cap questions - 01/31/14 06:00 AM

On my Mega block I used 100 on the mains and 40 on the side bolts with oil. But the key is whatever the machine shop that alight honed the mains but you may not know that, I have them or I stamp the torque specs on the pan rail)Torquing the mains first. I use a little silicon on the side bolt washers just to be safe from leaks.

Posted By: dvw

Re: Cross bolted main cap questions - 01/31/14 01:14 PM

Quote:

On my Mega block I used 100 on the mains and 40 on the side bolts with oil. But the key is whatever the machine shop that alight honed the mains but you may not know that, I have them or I stamp the torque specs on the pan rail)Torquing the mains first. I use a little silicon on the side bolt washers just to be safe from leaks.

I used these specs also. And since I was there when we were line honing it. I decided to remove the side bolts and remeasure when we done. It did make a small difference whether the side bolts were installed. Mine is an older Mopar Mega Block.
Doug

Posted By: '72CudaRacer

Re: Cross bolted main cap questions - 02/01/14 05:34 AM

Quote:

Quote:

On my Mega block I used 100 on the mains and 40 on the side bolts with oil. But the key is whatever the machine shop that alight honed the mains but you may not know that, I have them or I stamp the torque specs on the pan rail)Torquing the mains first. I use a little silicon on the side bolt washers just to be safe from leaks.

I used these specs also. And since I was there when we were line honing it. I decided to remove the side bolts and remeasure when we done. It did make a small difference whether the side bolts were installed. Mine is an older Mopar Mega Block.
Doug

Thanks for the info guys. I believe this is also a old mega block. It is massive in some areas (lifter bore area for one). If I treat this like a Hemi, my old book says 100 ft-lb on cap bolts and 45 ft-lb on tie bolts, however, it doesn't tell me the procedure to use. I think I'll be fine.

Thanks,
Brian

Posted By: rickseeman

Re: Cross bolted main cap questions - 02/04/14 04:53 PM

Torque all the main cap bolts first, then the side bolts.

Posted By: Cab_Burge

Re: Cross bolted main cap questions - 02/04/14 07:52 PM

Quote:

Torque all the main cap bolts first, then the side bolts.

Thats the way I do it on all of them including the aluminum KB blocks with four side bolts

Posted By: Mopar-Al

Re: Cross bolted main cap questions - 02/04/14 09:58 PM

My IndyMaxx aluminum block is stamped on the pan rail saying 80 top 70 side

Posted By: dvw

Re: Cross bolted main cap questions - 02/05/14 01:37 AM

Quote:

Torque all the main cap bolts first, then the side bolts.

I agree. Brian mine is an old Mega block also.
Doug