Originally Posted By: Lifeguard
Originally Posted By: tlowe #1716
To help clear up some stuff.
The lumps have been proven to make more power.
So do valve enlargements and larger cams.
A 292 engine with stock cam and head was ran, then was tested again with only a lump added. Basically no change in power was recorded.
Once a larger valve was used, the power went up.

Another test was done with the 1.94 valved head to remove the lump. The power went down. This confirmed the lump really does add power with larger valves.

All the 250 and 292 Dyno tests were performed by me.

Here is a page from my website that shows some dyno runs performed on the 292.
http://www.12bolt.com/65279inline-cylinder-head-flow65279.html


Yeah, that's what I remembered. Adding lumps and valves together gives the power.


You don't have to also add bigger valves with the lumps, a bigger cam also made more power with lumps and stock valves by adding more cam as well according to the dyno results, 31 HP more to be exact. Sure adding bigger valves can too but so did just adding a bigger cam with the lumps.

Even though there isn't much cubic inch difference between the 230 and the 250, it still isn't going to have the low end torque and power you will get with a 250 regardless of the mods you do. The stroke difference makes a huge difference in smaller engines.


Class III CNC Machinist/Programmer