Any luck getting time with the CMIs bob?

Some exhaust manufactures are may be afraid of what your testing will show...

Haven't heard anything on CMI's. Engine is going back on the dyno this week.

Good deal. What drive do you run 900hp through?

LOL. Bravo XR...It gets run very easily.

Any results with the Raylar and manifolds yet?

Yep, just haven't had a chance to update the web site. With the Raylar kit and stock exhaust (turbulators removed) made 530 at the flywheel with full wet exhaust. Switching to the Dana's it made 553.7. The boat went from 63 stock to 73 with the Raylar kit and exhaust.

Wow, that's really good. That means the Dana's made about 32 hp over the stock manifolds (if not turbulator modded). With the Dana's, I believe that puts the Raylar package a little over the Merc 525 (it's around 540?) Very good!

The speed gain is what I would have predicted for that hp increase on a stepped v single bravo. It proves you're getting the performance from those new horses :cool:

Thanks for giving us real facts and numbers :D

The raylar kit with cam, roller rockers, intake, and heads? Upgraded fuel pressure via PCM? W/O the cam can one expect 540hp?

NO

Best Regards,
Ray @ Raylar

Bob, what was the A/F at max HP?

13:1 seems to be the magic number. Power started falling off if richened past about 12.8:1.

At what A/F above 13:1 did the hp start to fall off?

At a point where the EGT's get so hot that the pistons and exhaust valves will start to burn with sustained rpm and load, Hot Tip! Don't go there!

Ray @ Raylar

LOL @ Ray....Bill, It really didn't lose much if any power going leaner until you got beyond 13.5:1. As we started going richer 13:1 was the optimum point before power started falling off. You definitely want to be on the rich side of that curve.

Thanks Bob and Ray for the reminder and the information. I know I do not want to go there. It was just an idle curiosity question steming from when we leaned out my engine on the dyno and the hp plumeted.

Bob, what was the fuel pressure that generated the 13:1 on the Raylar setup?

Rage,
The following is from a post I put up some time ago. It is the best explanation on interpreting the interrelationship of AFR/Timing/EGT/BSFC, ect. I have seen.

I apologize for the long post but this is very good information that will hopefully shed some light on the subject courtesy of Larry Meaux.
BSFC and Exhaust Gas Temperature (EGT) Information ;
In the old days of dyno testing , the dyno instrumentation
back then consisted of measuring Torque and engine RPM .
The dyno "luxury options" were also the ability to measure
fuel flow and exhaust gas temperatures , now these options
are standard equipment on modern dynos.

Fuel Flow readings are used to measure how efficiently
an engine was at turning each pound of gasoline or methanol
into HorsePower , in other words , how much fuel was being
consumed per HorsePower . The resulting terminology ,
is named "BSFC" or Brake Specific Fuel Consumption .

Brake = meaning as measured on a dyno water brake

Specific = results obtained relating HorsePower to Fuel Flow

Fuel Consumption = the amount of fuel consumed in Lbs. per Hour

the BSFC equation is ;

BSFC = Fuel_Consumed / UnCorrected_Brake_HP

.450 BSFC = 225 Lbs. Fuel per Hour / 500 UnCorrected HP per Hour

Note= UnCorrected HP means the raw , uncorrected HP as measured
in the current dyno room weather conditions , and as yet
this raw HP has not been corrected to Standard Weather
Conditions (ex=29.92" Baro, 60 deg F, 0 % Rh)
or has any other corrections such as Friction Torque
or to account for inertia losses due to acceleration,
have been made to the raw dyno room HorsePower numbers .

BSFC numbers are a means by which you can judge an engine's
efficiency. Also, BSFC numbers are often looked at
as representing "Rich" or "Lean" engine conditions .
That concept is somewhat true, but not totally true or
exactly how the BSFC information should be interpreted .

Examples of BSFC and EGT number misconceptions are ;

1- An engine is being dyno tested , and is tuned to its best
and proper Air/Fuel Ratio , and its BSFC is recorded .
If some person were to pull off a spark plug wire during
the dyno test, the BSFC would instantly skyrocket !!!
The resulting BSFC would then be higher , and could easily
be misinterpreted as going RICH , but in reality, the
Air/Fuel Ratio would have basically remained "unchanged" !
Both an EGT temperature probe and a Oxygen or Lambda sensor
on exhaust would indicate the engine went richer also ,
but in reality an Air/Fuel Ratio meter measuring the engine's
"Consumed" A/F Ratio would have remained unchanged .

2- An engine is being dyno tested , and is tuned to its best
and proper Air/Fuel Ratio , and its BSFC is recorded .
If for some reason , the distributor came loose, and
ignition timing went retarded, the BSFC would also "skyrocket"

All it did was start burning the same correct A/F Ratio later
and was continuing to burn as it went out exhaust ports
as you were pretty much wasting it and sort
of blow-torching the EGT probes

This last example would be "doubly perplexing" to the
novice observer because the BSFC will be higher
falsely indicating the engine went "Rich" , and the EGT temps
will be very much higher , falsely indicating the engine went
"Lean" ,....both occurring at the same time and instant !!!

In reality neither the engine went "Rich" or "Lean" ,
instead the "consumed" Air/Fuel Ratio remained unchanged !

There are many more examples of EGT , BSFC, and A/F Ratio
misconceptions, but the above 2 examples are primary reasons
and sources of racer confusion .

Sometimes i've seen a few racers come to my dyno and dyno test
their engines ...we make a few pulls, and i tell them from the
computer readouts what the A/F Ratio is or what the EGT temps are;

Some racers respond by ;
1-if i tell them its rich ...they want to increase ignition timing
to change the jetting

2-if i tell them its lean, ....they want to retard ignition timing
to change the jetting

Then i ask them ;
"How can increasing or decreasing ignition timing "
magically "UNSCREW" and "REPLACE" that jet in your carb ?????

The "Consumed" A/F Ratio remained basically the same,
no matter what you do with ignition timing .

What they "perceive" as Rich or Lean moving the ignition timing ,
are the EGT temps growing hotter or colder depending upon which
way you move timing ...and the BSFC numbers getting higher
or lower depending upon which way you move ignition timing .

Moving ignition timing will NEVER unscrew and magically replace
the jet in the carb with a new jet size !

You should tune by the "Consumed" Air/Fuel Ratio readings ,
then look at EGT temps , ...then and only then use these
EGT temps as a tuning "referrence" and not as the
"Last Word" in proper engine tuning !!!
If timing is too retarded , the EGTs will be very high
for a particular A/F Ratio and Compression Ratio/ Boost psi

I go after ignition timing 1st...we keep moving ignition timing
a step at a time one way or another, to find best combo
of torque/hp...then we go back and play with jet sizes
to fine tune ...if you go after jet size 1st with wrong timing,
sometimes exhaust conditions during overlap can affect
jetting slightly , if the racer happens to have mostly
header specs on edge of being wrong , or intake specs or
overlap period on edge of being wrong for rpm range.

Then after the engine is tuned for best average torque/hp
curve,....note the EGT temps as a reference !
but only as a reference , not the final word in jetting .

I use EGT probes to tell fuel distribution and other things ,
i never use or heavily rely on EGT as A/F Ratio determination
Using the EGT probes for fuel distribution studies is
their greatest value !!!!
You can't ask some other racer what EGT is best for you .
example= no matter how well you tune a 9:1 normally
aspirated engine, its EGT's will be higher than a similar
properly tuned engine with 15:1 Compression Ratio .
....no matter what you do , the 9:1 CR engine is going to have
higher EGTs because it will waste heat out exhaust more than
a 15:1 engine, or any CR higher than the 9:1 CR reference point .

If you asked a group of racers that all had their engines
perfectly tuned and maxed out with the best possible ignition
timing curve and A/F Ratio ....
one racer might say 1350 deg F ,
another might say 1250 deg F ,
another might say 1150 deg F,
another might say 1050 deg F
.....they could all be correct and have the very same A/F Ratios
.....the varying EGTs depending primarily upon Compression Ratio,
Volumetric Efficiciency percent % , and Combustion Chamber/Piston
top design .

You can dyno test the world's most perfectly tuned engine
with the most stable , most perfect A/F Ratio ,..it might have
1150 to 1250 EGT for an example .......
then dyno test this same engine at zero deg TDC ignition timing
advance under full load for a half an hour or so,
...you're going to completely melt the headers off the engine
in half an hour, thats is if it lasts that long
and doesn't 1st cycle/snowball into severe preignition
then detonation ! all the while its A/F Ratio would be perfect ,
but the EGTS will have gone thru the roof !!!
that is if you still have a roof in the dyno room
and it wasn't burnt in the fire caused by the melting headers .

Another thing you have to watch out for is
where are you placing the EGT probe??
1-at 12 o'clock or so ...
2-How far away from heads exh port flange ???
3-How deep is the EGT probe protruding into header pipe diameter ????
4-EGT probe type and response time

all these factors greatly infulence EGT temps making
it very much impossible to directly compare EGTs between racers
if no standards are set to probe placement

So basically , if you walk around the pits at a National Event
and ask the SS racers that have CR from 9 to 11:1 mostly ,
they'll tell you 1250 to 1350 EGT and maybe a few at 1450

you ask the ProStock and Comp guys with 16+:1 CR
they'll tell you 1000 to 1150 deg F
maybe some of the very large Mountain type engines
with HiCr tell you 850 to 1000 deg F EGTs

Hi Compression Ratio = Lower EGT temps
Low Compression Ratio = Higher EGT temps

Correct ignition advance(32+ to 40+ ign deg range)= Lower EGT temps

Wrong ignition advance ( below -25 or so deg range)= High EGT temps
..... burn slower and later in stroke , continuing to burn
while exhausting and if severe...cycling/snowballing into rising
coolant temperatures, preignition, then detonation.

Rich A/F Ratios = Lower EGTs (also extremly lean, misfire)

Lean A/F Ratios = Higher EGTs ..burn slower and later in stroke ,
continuing to burn while exhausting if severe...cycling/snowballing
into rising coolant temperatures, preignition, then detonation.


Some more aspects of EGT tuning ...
Example-> 4 cyl engine

Engine #1 cyl #2cyl #3 cyl #4 cyl
RPM EGT EGT EGT EGT
5000 1350 1250 1300 1325
....
....
8000 1390 1370 1390 1390

i would be worried about the
Number # 2 Cylinder out of the 4

Look at the "RATE of CHANGE" in EGT temps

Number #2 cyl starts off low , ends still lower than
others but its RATE is quicker

during a short 600 RPM/SEC dyno acceleration test
you might see engine's EGTs like above example

but if you were actually racing this same engine
in a road course or relatively long race
the number #2 cyl would grow way too hot ,
its EGT would out pace other cylinders and cause failure ???

Look at "RATE of CHANGE" !!!!
also at the lack of "RATE of CHANGE" in EGTs

I don't really remember, but it's irrelevant as a reference, since the PCM was reprogrammed anyway. We didn't go much higher than stock so I would guess around 45 PSI. No where near the 50 required with a stock PCM.

Thanks Bob. I missed the fact that the ECU had been recalibrated.

Thanks. Yes I saw your post before and archived a copy. Great info that is usually not seen.

Ray, what A/F do you recommend for your BCK103 package?

It varies with rpm and load but at WOT I like to see it at 13.0 to 13.2 EFI only. For those who are supercharged don't use these figures!!

:d

Ray, how is your price structure set up for your parts? I noticed several are priced the same even with added parts.

Not sure what you mean exactly, give me an example.

Regards,
Ray @ Raylar

BCK 101, 102, & 103 are all $6360...?

Thanks Ray.

Sorry guys, just discovered through your comments that our Webmaster made some pricing mistakes when updating the website. Our truck kits like the 101 and 102 should be shown as 3840.00 each and the 103 kit is 6360.00 as shown and the 106 kit is shown correct. Looks like I am going to be checking his website work more carefully. Just doesn't seems to be enough hours in the 7 days I work.

Regards,

Ray @ Raylar

Ah...thx for clearing that up. A little better on the wallet now ;-)

Use aircraft paint stripper and you'll need to use a wire wheel over the welds. You can buy a metal polish kit at Lowes. I did mine after Ray set me up with his 203 cam and ecu change and turbulators pulled too.

http://www.stingrayboats.com/MySting...230sx_2483.jpg

DPA, what all did you install and how does it perform?

Hard to tell. It was the 375HP 496 and I was loaded good with the whole family and full fuel. I installed Raylar's 450HP cam kit and stage 2 ECM recal. Pulled the turbulators. The best this boat did was 73 on speedo by the prev owner. I got about 2 MPH better and running at 5100 RPM. Ray told me to run at 5200. I think once we get the over rich condition solved (sooty transom) and a average load I could see a few more MPH. I may need a prop change if I run 1/2 fuel and two people. I just need to talk to Ray now. :(

FYI: Raylar testing update
 

Got this from Bob today. He should have the original link updated w/the info soon but here's a preview. Go to: www.fullthrottlemarine.com and click on High Performance Projects for the full story.
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"We’re back. Several months have passed and we’ve completed the Raylar install and testing. Sorry it’s taken so long. Just too much work and not enough time. As this article is directed at results, I’ll save the details of the install for another time. The instructions were thorough and it went together without a hitch. Now it’s back to the dyno to see what we accomplished. The one caveat to the project is that we sent the PCM to Whipple for their stage 2 programming. They tweak the fuel mixture, raise the rev limiter and adjust the spark timing to be much more aggressive. This requires a 120 degree thermostat and 91 octane fuel. We installed the stock exhaust manifolds, with turbulators removed for our initial tests. We made several pulls, tweaking the fuel pressure up and down to get a feel for what air fuel ratio worked best. It made best power at 13:1 air fuel ratio. More than a few points either direction and the power started falling off. Off course this is what Ray had already told us, but being hard headed we had to see for ourselves. The numbers? 530 HP at 5400 RPM. We’ve already established that the turbulators cost us 8 HP, so I didn’t see a need to revisit that. Keep in mind that Raylar’s testing was done without water mixing with the exhaust, whereas these tests had complete wet exhaust. This would certainly account for some HP loss as compared to his testing. Next we bolt on the Dana exhaust manifolds. Again we make several pulls to adjust the A/F ratio and arrive back at the 13:1 number. This time we get 553 HP at 5400 RPM. Very nice numbers and right in line with the manufactures claims. Let’s see what it does in the boat. This time the test conditions were the same altitude as before, about 10 degrees warmer air temperature and smooth water. We were able to consistently get 72 mph with a best of 72.8. Cruise A/F ratio is a bit lean so we were forced to raise the fuel pressure a couple of pounds to bring that in line for now. We’ll send the PCM back to Whipple for some fine tuning in the fall. In summary, with the Raylar kit, Stage 2 programming and Dana exhaust we picked up 9 mph. As a comparison, these numbers are slightly better than what that boat will run with a Merc 525 EFI under the same conditions."
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He also mentioned that one of his Raylar customers recently had an opportunity to race an identical boat to his, except it had the Merc 525 EFI engine. They ran dead even for about 5 miles.

Here's a link to the entire article... http://fullthrottlemarine.com/496%20...%20Article.htm

Brake fluid takes paint off.

Bob,

When you tested the Nordic "S" exhaust routing versus straight out exhaust routing, did you happen to have the IMCO corner exhaust tips with internal flappers installed that Nordic uses with the "S" setup?

Are the Raylar setup hp numbers from flywheel or prop shaft?

Thanks,

Bill

No, I didn't have the Imco tips installed, they were straight tips.

Raylars numbers are at the flywheel.

Bob

Excellent addition to an already excellent test program to clarify the effects of various components on hp.

Great info!

Bob, this is great information! I have a 31 foot Scarab II with twin 555ci / 700 HP / NA / TRS setup. If this was your setup, what exhaust would you use, Danna, IMCO, Lightening, CMI, or KE? I need to purchase two sets next week and you would obviously have more non bias knowledge then 99.9%. Any suggestions would be just as helpful as your awesome testing. Thank you for educating me.