Chamber Grooves - what do you guys think?

RoDyne · Post by **RoDyne** » Thu Feb 16, 2006 10:35 pm

For What It's Worth:

Just received April issue of Popular Hot Rodding which is the publication that sponsors the "Engine Masters Challange". Starting on page 25 is a teardown of the current winner of this years challange. The 508 cu in BBC built by Tony Bischoff and team at BES Racing Engines made 838 HP on 91 octane pump gas. On pages 26 and 28 there are clear pictures of the grooved piston with five slots, three on one squish pad, two on the spark plug side pad. (There are no grooves on the head.)

I'd say there must be something to this "groove" stuff or you wouldn't find it in this motor.

Grocerius Maximus · Post by **Grocerius Maximus** » Thu Feb 16, 2006 10:42 pm

V Remian wrote:If grooves swirling the incoming mixture are so efective-what happened to the mitubishi and honda jet valves?

Jet valves with the separate port and carb barrel were working on the stratified charge concept.

putztastics · Post by **putztastics** » Thu Feb 16, 2006 10:46 pm

automotive breath wrote: This will likely hurt more than it will help.

Are you talking about the grooves??

automotive breath · Post by **automotive breath** » Thu Feb 16, 2006 11:27 pm

putztastics wrote:Are you talking about the grooves??

Nope, I'm talking about teasing you with a trip to the south. It snowed here once, I have pictures.

automotive breath · Post by **automotive breath** » Thu Feb 16, 2006 11:54 pm

SupStk wrote:I had considered trying this modification and testing on the dyno until I read you couldn't prove it's benifits that way. Also I believe in Somender Singh's website it mentioned that the piston to head clearance had to be increased. If it was just a case of doing the heads, I'd go for it, but doing the whole engine to test by the seat of my pants..... I don't think so.

Pulling the heads and cutting the grooves is all that is required. The piston to head clearance does not need to be increased. I like to go with 10:1 compression at a minimum. The grooves have a more pronounced effect with high compression.

putztastics · Post by **putztastics** » Thu Feb 16, 2006 11:57 pm

Oh ok.

I've been to the Beaumont,TX area in Decenber, it was wonderful.

hbps1978 · Post by **hbps1978** » Fri Feb 17, 2006 12:42 am

Automotive Breath, I love the blue 1967 Camaro!

automotive breath · Post by **automotive breath** » Fri Feb 17, 2006 12:57 am

hbps1978 wrote:Automotive Breath, I love the blue 1967 Camaro!

Thanks, it's been with me for 25 years. It's a Boggie Scott built C Super Modified car from the 70's. I dumped the 4 speed and the 6.14 gears long ago.

Unkl Ian · Post by **Unkl Ian** » Fri Feb 17, 2006 1:58 am

If they can't be measured on a proper dyno,
how is anyone supposed to prove the benefits ?

I also noticed they made more than one change at a time.

SupStk wrote:I had considered trying this modification and testing on the dyno until I read you couldn't prove it's benifits that way...... I don't think so.

MadBill · Post by **MadBill** » Fri Feb 17, 2006 6:38 am

It's true, as the saying goes: "the proof of ther pudding is in the eating", i.e. track performance, but when an engine is so well developed that power increments are coming in the single digits (or even fractions, as Darrin and others could probably confirm) they cannot be individually confirmed on the strip. You have to work away at them one at a time on the dyno and hope that the cumulative effect carries over to give you an edge at the track.

67RS502 · Post by **67RS502** » Fri Feb 17, 2006 8:47 am

Joe Mendelis wrote:Is he the one that works at Faerman's?

yea he still does stuff at Faermans.

putztastics · Post by **putztastics** » Fri Feb 17, 2006 11:50 am

Grooves testing has commenced.

We are adding a sound recording of engine idle before and after to the test regime.

The absolute barometric pressure is 28.4 here now, that is way higher than normal.

It was -21 last night.

putztastics · Post by **putztastics** » Sat Feb 18, 2006 12:12 am

It must be a Chevy thing.

beth · Post by **beth** » Sat Feb 18, 2006 12:23 am

That was a long day of testing for you. Thanks so much for the effort.

beth

putztastics · Post by **putztastics** » Sat Feb 18, 2006 9:11 pm

There was a torque gain of about 3% in the 2200-3500 RPM range in the 4000-2000 WOT tests.