What I meant to demonstrate was that leaning out a fuel mixture (every combination is vastly different) can increase power. That's been known for years. Its just that with grooves, that ratio is leaner than without grooves... again, depending on the combo.

17:1 is a valid number, given that there are a few grooved combos running that exact ratio. Its simply that I believe that the grooves provide that environment and you don't. Simply disagreeing, lets leave it at that.

Ok, what is BSFC????

And while we're on lots of letters and what they mean, anyone know what the "BVD" stands for in the mens underware brand?

And just yesterday, I learned what "cow magnets" were!!! LOL (watching the history channel!)

Brake specific fuel consumption. It's a measurement of fuel flow into and out of the engine, via a return line. Measurement units are in lb's per hour of fuel per horsepower. .5 to .55 BSFC is typical on an average engine. .39 to .42 BSFC is indicative of a very efficient motor. Many, many, many variables go into a low BSFC result. Carbs have an impact, intake design is a biggie, cylinder heads, camshaft.

My involvement with the 360 Dodge testing was the groove layout and dimensions. Jessie decided on the test parameters.

Some important points to consider: The engine was not knock limited because of the fuel in use. The “after” test was run on the tune-up determined during the initial test. The modification lowered the compression ratio by increasing the chamber size by the volume of the grooves.

Looking back its likely that different results would be had if test parameters had been different. I believe the primary benefit of the modification is to reduce burn time resulting in reduced detonation tendencies. The test did not measure engine knock limitations.

The point that interest me was after the engine was delivered to the customer and it was installed in a car, it performed at 11:1 compression on pump gas with no detonation. This was a surprise to the engine builder.

Rick, Last weekend I was awarded “Sportsman of the Year” at the local race track because of my accomplishments regarding engine performance. You may be wondering what does that prove. To you maybe nothing, to me it proves that the people that know me and are involved with what I’m doing recognize my contributions to the sport.

Pulled up the specs on GM's HT383 crate motor which uses the same heads and cam as my build (decided to run the 14097395 Marine/Ramjet/HT factory roller) and has 9.1 SCR compared to my calculated 9.2. The HT383 is a 4.000" bore with a 3.85" stroke so I would say DCR might be slightly higher than mine. GM recommends this engine for light trucks using 87 Octane. I think I'm safe.........

AB,
Congratulations and keep up the good work.
Thanks
x

Thanks, The same day one of the cars I'm working with put down some impressive numbers. It's a late 80's Camaro with a 355 SBC and a T350. The weather was good and the car was working great.

60 ft. 1.299
330ft 3.997
1/8 6.258
mph 108.63
1000 ft 8.221
1/4 9.895
mph 134.22

The Engine Masters are using it.

http://www.popularhotrodding.com/te...uild/index.html

This written by another one of the top EMC teams, from another forum.

I think Buick had something like this in mind when they made heads for the 3.8/4.1 V6's.




Larry

I love reading this stuff . . .

Especially the link to the EMC stuff - couldn't believe it when I saw those grooves in the pistons.

Sure seems like someone with that kind of knowledge and dyno time would be able to tell whether or not this was worth anything. Maybe his actions have said something . . ..

Now why would they use "Ross Custom Pistons" but rossd doesn't make rings for it either? Whatever.

Hi Larry,
Nice porting! I have never seen that indention before.

GM decided to put an inclined plane in the LT1 heads during the 90s. This head has been milled removing some of the area; it is to the right of the plug. It looks like they were attempting to induce a swirl in the chamber.



hotrodf1,

This statement says it all,

“Our combo was pulled down to 1,900 RPM at WOT with an 1150 dominator with out missing a beat. No detonation at 10.5 to 1 nor 12.5 to 1 on pump premium”

The actual article mentions that they have no idea what those grooves did or did not do. There is no way you can infer they had any direct impact with the dyno results, as again it wasn't tested and verified. What you can draw a conclusion on though is the MANY other areas which contributed to that engine making power. Tight quench (.035), combustion chamber and piston designed to mirror each other, relocated plug location, attention to camshaft lobe design, intake manifold design and on and on and on. Many of those design elements were throughly tested and verified as stated in the article.

Rick,

I think you and I are talking about two different EMC entries. The quote I posted was not from the BMS team but rather from another top EMC team running grooved heads.

IMO every component of and engine that runs 12.5:1 compression on pump gas needs to be considered as part of the total package that is capable of doing something extraordinary. I'm sure the combustion chamber itself was state of the art design.


edit:
I responded too quickly, I should have realized you were responding to the quote in your post, sorry.