Bad 502 pump gas Piece by Mesa
 

Guys we've been busier than a one armed paper hanger around the shop but here is a project you guys will enjoy one of our friends and fellow racers contacted us about taking his new 502 and doing what ever we could to make the most power on pump gas we felt confortable with. I started by saying I would dyno the existing engine to start and I felt we could make around 640 hp on pump gas. The dyno started at 540 hp we took the engine completely apart decked teh block to get the piston to head we wanted balanced the assembly reconded the rods with arp bolts . I had Cam Motion grind me a solid roller with tight lash profile for the heads we were using which Brodix supplied for us . We had the heads cnc ported with some changes from our original MB850na head installed a Brodix intake with an 8082 holley which we tuned here. We started the engine and made the first pull the power was way off we started looking and the distributor hold down clamp had colapsed and the dist. moved set the timing and after it was done we had made 698 hp and over 600ft lbs everywhere I call the customer and told him were we were and I was going to come in on Sat. and finish it up when I was done I made 738 hp and the torque curve was flat as a board. The boats speed is up and the customer happy. Pump gas under 11.00:1 comp. Sincerely Laz
P.S. this is the most power I've been able to make with a 502 Std bore.

Re: Bad 502 pump gas Piece by Mesa
 

A couple more pics

Re: Bad 502 pump gas Piece by Mesa
 

What rpm for 738hp?

Re: Bad 502 pump gas Piece by Mesa
 

6500 rpm

Re: Bad 502 pump gas Piece by Mesa
 

Which heads did you run Laz, and were they cnc'd by the factory or a private shop.

Re: Bad 502 pump gas Piece by Mesa
 

I have a private individual who does some of our cnc work we've worke together since the 80's back when it was all hand done these were finished at 346-348 cc intake runners and flowed right at 405 cfm with a 2.300 valve . They have a trailing boss that goes all the way into the top of the valve guide which we hadn't done before and we've seen 35 ft lbs over our other cnc programs I feel it's one of the best ports we've made until now.

Re: Bad 502 pump gas Piece by Mesa
 

Post the dyno sheet, please.