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Aftermarket 426 hemi blocks

Posted By: CuDa572

Aftermarket 426 hemi blocks - 03/03/14 05:19 AM

Hey guys! How much horse power can the mopar performance production street hemi blocks handle?
Posted By: Mopar_Rich

Re: Aftermarket 426 hemi blocks - 03/03/14 06:23 AM

Depends on several things. Unfilled, without a stud girdle, I'd say in the 600 HP area. I have seen several RB blocks fail in race applications in heavy cars at 700 HP. A stud girdle helps a lot, as does filling the block to the freeze plugs. I have several friends running 750 HP with girdles in fully prepped blocks.

Mega blocks are the way to go unless it's a matching numbers thing.
Posted By: Cab_Burge

Re: Aftermarket 426 hemi blocks - 03/03/14 09:05 AM

Quote:

Hey guys! How much horse power can the mopar performance production street hemi blocks handle?


I've made around 800 HP N/A with them (Mopar replacement Hemi block) with no bad results, the key is it a race motor or a street and strip motor and who is driving and tuning it I have one with a blower on it making over 900 HP on pump gas with 7 lbs of boost running on the streets now, not sure how many miles are on it as of now It is in the car on the cover of the Feb. 2014 Mopar Action magazine. BTW, it is a 484 C.I. motor, not what the mag writer wrote
Posted By: Mopar_Rich

Re: Aftermarket 426 hemi blocks - 03/03/14 05:16 PM

Maybe I should actually READ the subject of these posts before I stick my foot in my mouth and respond. My above response was for an RB wedge block with no crossbolted mains. The subject was clear - "aftermarket HEMI blocks" - I just missed it. I notice that happening more and more as I get older. It sucks!

Anyway, I totally agree with Cab_Burge
Posted By: Dragula

Re: Aftermarket 426 hemi blocks - 03/03/14 06:13 PM

Quote:

Maybe I should actually READ the subject of these posts before I stick my foot in my mouth and respond. My above response was for an RB wedge block with no crossbolted mains. The subject was clear - "aftermarket HEMI blocks" - I just missed it. I notice that happening more and more as I get older. It sucks!

Anyway, I totally agree with Cab_Burge





Rich,

I digress a little here. Are you migrating your site this winter? I might be interested in upgrading to the sportsman from my Classic depending on the way racing looks this year.

Back to blocks, an OEM Hemi block was ok up to 700-800hp, but oiling was somthing you had to make some changes for and I cracked a main cap and switched to Pro Gram Billets on the stocker...On the after market ones there is a lot more material in them in all the right spots and all the caps are cross bolted..Good for well into the +1000hp range...
Posted By: Mopar_Rich

Re: Aftermarket 426 hemi blocks - 03/03/14 07:49 PM

Quote:


Rich,

I digress a little here. Are you migrating your site this winter? I might be interested in upgrading to the sportsman from my Classic depending on the way racing looks this year.





What do you mean by "migrating my site"? I'm redoing the web site - yes, because customers want e-commerce. That is potentially problematic, because I feel it's a better idea to talk things over before placing orders. But I'll try to help that process with the site.
Posted By: racingblues1426

Re: Aftermarket 426 hemi blocks - 03/03/14 11:29 PM

I bought a standard mopar block. New, never touched. I raced it for 3 years as a 472.(666 hp) It ran and performed perfectly. Then I made it a 478--15.75c.r. 800in lift cam-Mopar cross ram intake/2 830 cfm carbs- Mopar perf. alum. heads, mopar crank,eagle rods in a 3000 lb b body. It made 836 hp on a dyno. Raced it 4 years,changed rod bearings every year and mains once. Sold it to a racer in Penn. and he is still racing it today. Maybe it was the Brad penn oil but never had any problems besides going through mopar starters until i bought a real starter. I never filled the block, added any trick things to make it last.
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