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Author Topic: Race Head Upgrade for the Standard Bullet Head  (Read 604 times)


  • Grand Gearhead
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  • World leaders in performance/racing Bullets
Race Head Upgrade for the Standard Bullet Head
« on: October 03, 2013, 11:14:01 am »
We have had this under development for quite a while now, but it is reaching the final stages, and it is going to production this month.

Basically, we are making a conversion system which will put a shaft rocker system like the Big Head has, on to the standard Bullet head. Then we are adding our high ratio roller rockers to it, along with the longer valves and beehive springs and titanium retainers which are similar to our Fireball valve parts, and adding our hi-port modification for more flow.  The port will flow in excess of 240 cfm @ 28" water column of vacuum on the flow bench. This is about the same as a Corvette flows thru each of its intake ports. It's intended for a racing or high rpm application, so there was not much attention to retaining copious low rpm torque. This is a high speed head mod. Lower end torque with this head is still decent, but the regular Fireball is already available for those who want that. This is for the high rpm guys.
Intake port photo attached below.

This will use steel racing pushrods that are non-adjustable, because the adjusters are being moved to the rocker arms. The pushrods will need to be much stronger than the stock items for this application, so we re-designed that part to sustain what this head modification is going to give.

The roller rocker system will be very similar to the one we offer for the Big Head, with similar ratio and features.
Since I don't have the finished standard head here to photograph, I attached a photo of the Big Head roller rocker system, to show what the roller rockers look like.

We are doing this to top off our line-up. We have a great street head with the Fireball, and now we are going to offer a racing head for the ones who want it all, and are willing to accept the responsibility of maintaining an engine in this high state of tune.
This will complement our Big Head Hi-port Roller Rocker modification, by doing approximately the same job for the people who don't have the Big Head. So, everybody use the heads that they already have, if they want to do this conversion/upgrade. As with our Big Head job, the potential for this will also be more than 50hp with a fully prepared engine that makes the most of the flow and features we provided.

We already have 4 heads here in the shop that are getting this upgrade, so we will be seeing and hearing results pretty soon!
« Last Edit: October 03, 2013, 11:25:52 am by ace.cafe »


  • Grand Gearhead
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Re: Race Head Upgrade for the Standard Bullet Head
« Reply #1 on: October 03, 2013, 12:29:27 pm »
I like it. I can see a future project.  ERC
2-57 Apaches, 2-57 Trailblazers, 60 Chief, 65 Interceptor, 2004 Bullet, 612 Bullet chopped.

High On Octane

  • Grand Gearhead
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Re: Race Head Upgrade for the Standard Bullet Head
« Reply #2 on: October 03, 2013, 08:42:54 pm »
That's awesome!  Race it up baby!     :D

Scottie J used to own bikes.  Now he just lurks around in the dark.