PICS: Ported Gen4 Viper Heads with Custom Valves and Dual Springs

[JMB Justin]

Just finished these up for Jason "seethrough", they are Gen4 Viper heads with our custom stainless 2.125 intake and 1.61 exhaust valves, dual valve springs good for .660 lift, and titanium retainers. Had very nice gains on the intake side, will be a huge improvement with his ~ custom .630 lift cam we ground for him. Exhaust had a moderate improvement, not near as much to get there as the intake side. Keep in mind that when comparing flow #'s, its like comparing dyno #'s, this bench obviously reads on the low side since the stock castings only flowed 305 cfm on the intake side, and the typical #'s I've seen are 15-20 cfm stronger than that. Notice the gains themselves, that's what really matters. The exhaust was measured without a pipe, figure another 20-30 cfm more with a pipe attached. Should be assembling this engine soon, just waiting on the block to come back from the machine shop.

 

[JMB Justin]

This package including:
New cylinder head castings
Ported/polished and gasket matched
New OEM rockers
Custom 2.125"/1.610 Stainless valves
Dual valve springs good for .660 lift
Titanium retainers
Valve seals
Pushrods
Competition valve job
Honed guides
Flat surface
Assembled and ready for install
Completely new top end minus intake/valve covers/fuel rails/headers/gaskets (All available through JMB as well)
Priced at $5299

BTW I checked the flow #s on some mildly worked ported Striker R Race heads we have here and they flowed less on the intake side until .650 lift and are 25+ cfm shy on the exhaust everywhere. Gen4 heads are an awesome bang for the buck!

Justin

 

[Stanimal]

God I hope this is still offered as a package in a few months. Can't wait to see the dyno results

 

[JMB Justin]

As long as affordable castings are available, these will still be available. These are going on a high compression twin turbo ethanol burning monster! There will be dyno results but not NA

 

[ViperPete]

I wonder how different Gen V heads are. Have you gotten your hands on any Justin?

Beautiful work by the way.

 

[seethrough]

Thanks for posting Justin. The available cores seem to be disappearing rapidly. I only see 3 left from the place I purchased these from. Here is the link if anyone if interested. New Dodge Viper Cylinder Head Bare 08 09 10 Mopar | eBay

One thing I noticed when I first got these is that one head had the combustion chamber CNCed and one head was raw. I exchanged the raw one but there is a chance that the remaining heads are raw.

 

[JMB Justin]

I wonder how different Gen V heads are. Have you gotten your hands on any Justin?

Beautiful work by the way.

They are the same

 

[JMB Justin]

Thanks for posting Justin. The available cores seem to be disappearing rapidly. I only see 3 left from the place I purchased these from. Here is the link if anyone if interested. New Dodge Viper Cylinder Head Bare 08 09 10 Mopar | eBay

One thing I noticed when I first got these is that one head had the combustion chamber CNCed and one head was raw. I exchanged the raw one but there is a chance that the remaining heads are raw.

Thanks for the opportunity Jason!

 

[seethrough]

Thanks for the opportunity Jason!

No problem Justin - glad to have someone close with the experience/skills to do this build. I'm looking forward to seeing where this thing ends up on your "wall of fame" signature.

 

[JMB Justin]

That will definitely happen, it's going to make insane numbers!

 

[stealth78]

Justin, How much would this cost if it were a turn-key conversion on a Gen 3? Is there any way to do this with the Gen 3 single throttle body or would it have to go the route of twins?

 

[JMB Justin]

With a ported intake (with Gen3 TB), valve covers, fuel rails, headers, tune, camshaft, gaskets, install, etc. You are around $13k. Should make an easy 600+ WHP, likely 625+ on 93 octane, depending on camshaft selection.
Justin

 

[stealth78]

With a ported intake (with Gen3 TB), valve covers, fuel rails, headers, tune, camshaft, gaskets, install, etc. You are around $13k. Should make an easy 600+ WHP, likely 625+ on 93 octane, depending on camshaft selection.
Justin

And in all seriousness, how much for a forged short block that would support this much HP plus a 150 shot? (Price just for short block, spray would be added later on)

 

[JMB Justin]

Engine pricing is here:

JMB Upgraded Viper Shortblock / Longblock Package - JMB Performance and Powdercoat

 

[stealth78]

Thank you sir!!! Not that my opinion matters but I feel as if that is perfectly priced! :rock:

 

[JMB Justin]

Thanks!