When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Wanted to share my latest build with you guys. I have a plethora of **** laying around and I had enough stuff to put together an LS3. Stock block, crank, and cylinder head castings with a used set of h-beam rods. Really the only thing new that I bought for this was a camshaft, pistons, and rings. Most everything else I had laying around. Did a few tricks with the short block to free up some power, and worked on the heads a good bit. Cut down and regrooved some titanium valves for the heads and put 7/16 stud mount rockers in them. Worked on the super victor a good bit to get it right. I put a vacuum pump on it but ended up having to run the engine without it hooked up. My goal was 750hp at 8000rpm. Finally got it buttoned up and on the dyno today. Here are the results
Most impressive for sure. I was impressed when Barrett made 650 HP with his stock bottom end LQ4 and L92 heads. Amazing what another 1000 RPMs can do. Makes me want to call Callies right now.
I see the dyno numbers bounced around quite a bit. Did it really have a torque peak of 6600 RPM? How much valve spring does this engine have on it?
Last edited by speedtigger; 02-01-2015 at 06:38 AM.
I don't remember valve length, I'd have to go back and look at my notes. I did the valves last year sometime. They are a little longer than stock length. It's been a project that I've been messing with in my spare time. Gross valve lift is just under .800" after lash.
Yeah it's a solid roller with hand ported 823 heads that had a nitrous exhaust runner.
interesting. we're using the 5364 rectangle casting and seeing some really nice numbers from hand porting. i'm building a stock bottom end and head 6.0 with super vic as well; so all of this is very very promising. my cam is well over 700 lift, but not 800 territory
The heads went 365 cfm. Cam was 272/288 @ .050", just under .800" gross lift. 1150 dominator carb and q16 fuel. The fluctuation in numbers was the load on the dyno. Had to turn the dyno out more because we didn't anticipate the engine to make that kind of power. Started out with a 950 4150 carb and picked up about 30hp switching to the 1150.
Last edited by WE TODD DID; 02-01-2015 at 10:33 PM.
Fourth column is observed (net)hp without any correction. Doesn't include the friction factor (borexstroke), or weather conditions. STP is standard temperature and pressure. Second column is corrected (gross)hp.
No I'm pretty sure I can get them to flow more, but they won't run any better on this engine. Flow numbers are a by product of a correctly sized runner for the given engine displacement and desired peak rpm. I could make these runners bigger, flow more, and slow the air speed down as a result, and it will lose power. When I put a cylinder head on the flow bench, I use it as a tool not to necessarily see how much it flows, but to listen to the port, making sure it isn't turbulent or start backing up. I can also change the entry radius on the intake runner on the flow bench and make the air do a lot of different ****. Just like the exhaust, if I stick a pipe on the end of the runner, it'll usually pick up about 25cfm depending on the port. There is a lot of manipulation in the cylinder head market in regards to flow numbers.
I'll give you an example of flow numbers. I can take a standard "ported" exhaust port with an 89% throat, and I can take the same port and open the throat to 92% and it will lose cfm, but it will run faster. With a smaller throat, you can get a nicer short turn radius and "flow" better, but it won't run as fast as the big throat.
Last edited by WE TODD DID; 02-04-2015 at 10:13 PM.
01-31-2015, 06:37 PM
Stock cube LS3 build 
