5.2 Predator block with Gen 3 heads - Which ARP head studs?

[bankyf]

Working on a 5.2 Predator build and I had purchased a set of coyote Gen 3 head studs (256-4302). While researching something else today, I came upon an article about Coastal Dyno from a few years ago in the early days of the predator mentioning that many people were damaging the predator blocks by using the wrong head stud, but of course no mention of what the proper one was.

“A lot of people have been trying to do what we are doing with these blocks and have had massive failures, 100 percent has been user error,” Sam explained. “There are several things that have to be done different on these things to make them work correctly. The block failures have mostly been from people trying to use Coyote head studs in them and cracking the water jacket etc. It’s an expensive lesson to learn so people try to blame the block, I’ve yet to have a single issue.”

I did find an old post on here with an answer (256-4302 or 256-4702), but it seems that ARP may have released some new products since then. The ARP catalog now has a listing for the 2015-2020 5.2 Vodoo (256-4303), but no mention of predator. I called ARP to find out the difference between the two and he tells me the 256-4303 is almost 2" shorter. As expected, he couldn't provide any advice for a Gen 3 head on a predator block. Is there a difference in the Vodoo head that necessitates the shorter bolt, or has ARP determined that the shorter bolts are more appropriate for the 5.2 block?

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[engineermike]

I can’t directly answer but I did install gen3 heads on a predator block using stock gen3 head bolts. They seemed to seat fine against the head. Though the motor is a spare I haven’t run so maybe they’re all cracked now…. But if it were a 2” difference I think I would have noticed.

 

[Kane]

Working on a 5.2 Predator build and I had purchased a set of coyote Gen 3 head studs (256-4302). While researching something else today, I came upon an article about Coastal Dyno from a few years ago in the early days of the predator mentioning that many people were damaging the predator blocks by using the wrong head stud, but of course no mention of what the proper one was.

“A lot of people have been trying to do what we are doing with these blocks and have had massive failures, 100 percent has been user error,” Sam explained. “There are several things that have to be done different on these things to make them work correctly. The block failures have mostly been from people trying to use Coyote head studs in them and cracking the water jacket etc. It’s an expensive lesson to learn so people try to blame the block, I’ve yet to have a single issue.”

I did find an old post on here with an answer (256-4302 or 256-4702), but it seems that ARP may have released some new products since then. The ARP catalog now has a listing for the 2015-2020 5.2 Vodoo (256-4303), but no mention of predator. I called ARP to find out the difference between the two and he tells me the 256-4303 is almost 2" shorter. As expected, he couldn't provide any advice for a Gen 3 head on a predator block. Is there a difference in the Vodoo head that necessitates the shorter bolt, or has ARP determined that the shorter bolts are more appropriate for the 5.2 block?

Did you get answers? What did you end up doing?

 

[Joshinator99]

Not sure if @AcceptableNebula knows the answer to this.

 

[AcceptableNebula]

It uses longer 187mm head bolts M-6067-M501280. They still fit thru Gen 3 heads according to my research. I will be putting that combo together in a couple months. From my research it’s 256-4303 as the 2020 GT350 block is the same as the GT500 according to MMR. They sell the studs under their own part number 350020B.

 

[bankyf]

Did you get answers? What did you end up doing?

Sold the car, sold the shortblock and sold the studs, so I never put that together. Recently bought the car back, have another 5.2 block I've been holding on to, and bought the same 256-4302 studs again. Everything I could find back at the time of the posting indicated that 256-4302 was the correct answer for coyote heads on a predator block. The studs were sold to the same person that bought the shortblock, and he never mentioned that they didn't work.

 

[80FoxCoupe]

Gen3 headstuds will work with Predator block.

 

[Kane]

Sold the car, sold the shortblock and sold the studs, so I never put that together. Recently bought the car back, have another 5.2 block I've been holding on to, and bought the same 256-4302 studs again. Everything I could find back at the time of the posting indicated that 256-4302 was the correct answer for coyote heads on a predator block. The studs were sold to the same person that bought the shortblock, and he never mentioned that they didn't work.

Interesting turning of event.. good luck & thank you!

 

[diambo4life]

Hey bro. I have a 5.2 block with Gen 1 heads here. You can use the ARP 256-4702 head studs. There's a few points you need to note during the install process though.

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