OMC reed test results (non race)

[racer]

First a little about the engine used for the test, it is a 183 cubic inch production based engine basically built to ODBA pro carb rules minus compression and a modified intake. It was tested with 155 psi compression and untouched intake manifolds, reed cages were lapped for inproved seal. Stock factory ignition except for a race flywheel. Mid section used was stock except for water routing needed for dyno use.

Dyno is a superflow with windyn data, room is about 12X18. Exhaust is thru a large muffler (city req.) and water supply from a 10K gallon tank, I thus can control water feed in volume and pressure to the engine cooling. Air parameters for the test were very close.

A base line beyond test parameters was established before the high compression heads and modified intake were removed, in this trim it made 400.5 horsepower after testing was complete it was retested to verify condition of engine and it made 399.4. After each reed test compression and leakdown were performed and they remained very consistent. If a test was done on a different day, the previous test was rerun to verify accuracy, no change more than .5 horsepower was noted.

Tests were run using 110 race fuel and 40 to 1 oil. Tests were controlled to the best of my ability including engine temp, I am including one run at a lower temp so you can see the difference it makes. All reeds were cycled thru different rpm ranges to verify reed durability, then a minimum of three pulls were performed.

First reeds tested stock prodution steel reeds with stops.
Peak torque 286.9 @5800
Average from 6000 to 7500
Torque 264.6 HP 338.8 Pounds fuel hour 197.7 BSFC .606
Average from 6500 to 7500
Torque 258.8 HP 343.6 Fuel 191.2 BSFC .577
Engine temp 128 degrees Horsepower fall off from peak to 7500 -19.6HP
EGT 1090

Second reeds Boysen 166 no stops
Peak torque 298.3 @5500/5800
Average from 6000 to 7500
Torque 275.2 HP 352.8 Fuel 212.7 BSFC .625
Average from 6500 to 7500
Torque 269.1 HP 358.2 Fuel 207.2 BSFC .599
Engine temp 129 degrees HP fall off peak to 7500 -4.2HP EGT 1070

Third Chris Carson .022 yellow with stops at 128 degree temp
Peak torque 283.2 @5600
Average from 6000 to 7500
Torque 264.1 HP 338.5 Fuel 196.6 BSFC .603
Average from 6500 to 7500
Torque 258.9 HP 344.5 Fuel 196.6 BSFC .592
Fall off 14.8 Hp EGT 1090

Same reeds at 119 temp
Peak torque 288.2 @5700
6000 to 7500
Torque 267.7 HP 343.2 Fuel 191.8 BSFC .577
6500 to 7500
Torque 262.4 HP 349.3 Fuel 192.4 BSFC .569
Fall off Peak to 7500 -11.6 EGT 1090
So you can see temp also effects these engines

Fourth TDR .022 white with stops
Peak torque 291.2 @5600
Average from 6000 to 7500
Torque 267.8 HP 343.2 Fuel 202 BSFC .615
Average 6500 to 7500
Torque 261.9 HP 348.4 Fuel 198 BSFC .591
Engine temp 126
Fall off peak to 7500 -7.8 EGT 1090

Of note,
All averages done by the computor, accel rate same for all and controlled by the computor at 600 rpm gain per second
All reeds in tack after test but Boysen had a few slightly open, causing a slight spit on restart
Best idle quality and starting Carson and TDR
Loudest intake noise Boysen

I am going to try and test thinner race type reeds on cut cages once I get some time including some sent that did not meet this tests parameters, one already tested. The above are reeds that should live well in every day use. Pictures to follow in a few days.

I would like to thank both Tony and Chris for their participation in this test. Total time involved 16 Hours two guys, fuel burned to much.

[jphii]

Great info Al, and much appreciated.

[lokinutz]

Excellent test, thanks again Al.

[baja200merk]

Great info, thanks for your time!

I cant wait to hear about the cut cages.

[400hpV8johnrude]

Verry interesting thanks again for publishing the results

[Instigator]

Total time involved 16 Hours two guys, fuel burned to much.

Always knew to do this test properlly/accurately would not be easy or cheap.

Al, how about the TDR's @ 112 ?

Thank you very much Al. Copied and saved info going into the "Bible".

[Dave S]

From the black side..... Thanks for the info. I use what reeds come wit the motor .

[HStream1]

Thank you very Much for your Time, Efforts, Out of Pocket and sharing with us.

[mrcrsr]

thanks for taking the time, its interesting to see that the boyessens made more power, but they didn't last, how about testing w/ no stops on the other reeds?

[michael_m]

thanks for taking the time and exspence into helping us with helpful info.Also would the CARSON or TDR reeds made the same power as the boyessens if they had the stops taken off them as u did with the boyessens was that the reason they possiably started to fail because they didnt have stops?

[xb03fs]

Kinda confirms what the what you read about on read all the time boyesons are great for a day and then they go downhill fast. TDR and Carson are a little better better than stock and built to last.

I guess you can't go wrong with TDR or Carson and they are better than stock, safer for your motor, and outlast the Boyesons

As I am sure you will hear a thousand times, THANK YOU FOR the time taken.

Now we have a HP test and a torque test to look at

[Jay Smith]

Just my opinion, Thanks Al and Noah you guys are the BEST !!!! I've ALWAYS contended that MY main objective is to have a reed that makes average or comparative HP BUT most important it MUST LIVE to the second round in HIGH RPM drag racing and or a COMPLETE SEASON ( S ) for my recreational boater customers. IMO this test confirms that my choice over the years hasn't been wrong nor will I change the reeds I install thats been living and winning season after season for me and my satisfied customers ... Thanks again Al and Noah for all your man hours and out of pocket money to do these tests, its been informative and an education .... Jay

[racer]

Thanks for the kind words, I enjoyed doing this test and learning as well. The Boysens were run with out stops as that is how they reccomend to use them, Chris and Tony asked to run stops. I have marked stops to see if the reeds hit them and not been able to see any marks, I have run Boysens with/ with out and not seen any change.

[ChrisCarsonMarine]

Thanks Al for interrupting your very busy skedual to perform tests to help us all understand our motors better.Information gathered by an experianced builder/racer,using state of the art equipment,in a controlled environment is undisputabe,and enlightening.We at CCMS are thankful to have had our reeds involved,and are looking forward to sending you our race and drag reeds,if you choose to test Hi-performance reeds in the future.
Sincerely
Chris Carson & CCMS

[Markus]

Al, thanks a lot!