Chamber Grooves - what do you guys think?

[SupStk]

The only way to know for absolutly certain would be to run the car at the track, pull the heads, cut them, put them back on and run it again.

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.

[putztastics]

I'm not sure I will do this testing tomorrow, I have been called in to work sick relief tonight and don't know if I will have enough time to get it done plus get some sleep. I start nights tomorrow. Plus we are having major weather change it is supposed to be -20F tonight.

Cheer me up peoples,

This is the plan;

Two 6200-4000 wot sweeps
Two 4000-2000 wot sweeps
Two 4500-2000 partial throttle sweeps using a throttle stop

LM-1 meter logs for every test plus a record of idle speed vacuum and A/F ratio.

Groove heads.

Two 4500-2000 partial throttle sweeps using a throttle stop
Two 6200-4000 wot sweeps
Two 4000-2000 wot sweeps

LM-1 meter logs for every test plus a record of idle speed vacuum and A/F ratio.

------------------------------

The partial throttle sweep tests will be done using a throttle stop bolted to the carb, I finished it up today. It is adjustable. I'll leave the carb bolted to the intake so the throttle stop position will not be disturbed. If I do the post groove partial throttle tests first the throttle position before and after grooving should be the same.

I think I will set it for around 150 tq to simulate part throttle cruising conditions. It might be good idea to do a steady state test against the throttle stop too for the most accurate reading possible.

[automotive breath]

…Forget about the dyno, run these things down the track!...

…Cheer me up peoples, …

What would cheer up "putztastics"? This will likely hurt more than it will help. We started our spring racing season a month ago, tomorrow I will be doing just what "airflowdevelop" suggests, that is running a grooved 355 down the race track.

Here’s the offer putztastics, you make it down to Louisiana and we meet up at Larry’s shop for a 355 dyno test. When finished we bolt it in one of my Camaros for weekend at the races. Can you think of something better to do with the week of vacation you’ve been holding onto?

[Ed Wright]

Is he the one that works at Faerman's?

I don't know where he works now. He used to do heads for Dennis Faerman, the Nickens boys and others. He used to turn out some bad-azzed Buick heads. Always lots of fast Comp cars out of that town. I believe he also did David Nicken's Pro Stock Hemi stuff. Jim Bell has been "at it", and very good, for a long time.

[RoDyne]

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]

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]

This will likely hurt more than it will help.

Are you talking about the grooves??

[automotive breath]

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]

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]

Oh ok.

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

[hbps1978]

Automotive Breath, I love the blue 1967 Camaro!

[automotive breath]

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]

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.

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]

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]

Is he the one that works at Faerman's?

yea he still does stuff at Faermans.