Off the shelf Cam- Dyno results
 

Here are my dyno results from today, Let's have some fun- I'll tell you everything but the cam spec....can you guess?
This build met all my desired results for the 45 Excalibur, looking forward to sea trial.
GM Gen VI Block
4.530b x 4.250s
Callies Crank
Eagle Rod
JE shelf piston
Dart 308 as cast head with high quality valve job
Victor JR
Custom QF 850ish carb
1'' 4 hole
GM roller lifters
XX Hyd Roller Cam
Whistled out to 9:1
[ATTACH=CONFIG]556453[/ATTACH][ATTACH=CONFIG]556455[/ATTACH]

Looks good to me! Man I love my "custom recipe" even more now... Good job!

Close to 741 specs?

close to 731.

These are 548s?

When do they go in the boat? Have a 45 also.

that is the bore&stroke to make 548.

ok sonic30ss,spill the beans.

Im thinking 741 crane myself. Or close to it.

Dart 308 irons and shelf cam, with prob quite a bit less lift, spanked you right in the azz :poopoo:

Ok- Comp version of 525 efi cam.
Happy motor
https://youtu.be/NNnPRrlXK34

Granted was with dyno headers, but still stout, hopefully reliable power.
No race fuel either Shell 93 out of the pump with 32 degrees timing

Shooting for next week, have to hang transom assemblies and finish odds and ends in the bildge this weekend

So what is the actual Comp Cams part number?

01-446-11 pn
XM289HR-14 Grind #

Winner, winner. !!!!!

Lol correct!

PS SB thanks for the tip on the sp vs dp debate! No problem building torque in this build ��

235/243 .610/.627 114 LSA cam.

http://news.compperformance.com/wp-c...I-Camshaft.pdf


Nice combo. Should work well in that big 45 Wellcraft. Excellent torque. Should live a long time , as the lift is reasonable. No .680 lift needed to make the power,and I'm sure the valve spring pressures are reasonable as well.

I really feel that subject matter is not a debate. Some things are just what they are.

Are those A/F ratio's from wideband ? Appears so. If they are , looks like one side of carb could stand a little more fuel.

Good luck with the boat - looks like the engine part went well.

That is a nice flat torque curve.

The debate I referred to was in my head, after I looked at the facts, it was over

Yes there are 8 widebands you are looking at cyl 3&4, that run was without air filter, installing it cost 2 hp but also evened out the a/f

Great, on all 3 subects.

What flame arrestor are you using ?

Hey Joe how are those Bravo Threes going to like all that torque ? Send me some pics of the boat when it's done I would like to see the transformation. John

Agreed I wanted to keep lift at a "reasonable" level. I spent many many hours agonizing over cam selection. I reviewed as many dyno charts as I could get my hands on, asked for recommendations from a bunch of suppliers. One thing stood out on every one of the dyno pulls was a torque dip sometimes as much as 500 rpm wide right where I didn't want it in the 3000-3700 range. Granted they aren't huge losses but, with what I'm trying to accomplish with this heavy boat, I could not afford to loose anything in that range.
Could it be something off in the combos, yes but I surmised it might be low airspeed caused by opening intake valve too fast, too early or too high, reducing air speed and not filling the cylinders completely until air speed picked back up at higher rpm.

I don't post much but read A LOT and your posts about cams made me think very carefully about cam selection

Yea I know! Sent a text to my drive guy yesterday apologizing in advance lol
But we did find out that they are not std BIII, they are one of the Xs. We ordered new upper seals based on drive SN on engine plate and they were too small. So they've been replaced at some point and internally they look great....fingers crossed need to get thru this season

Sometimes that torque dip is just a result of the dyno catching up with the motor.

Other times it is caused by exhaust tuning resonances.

Some times it is caused by the cam.....but wider LSA like yours tends to keep this away. Results in flatter torque curve...well, almost a flat line. Good ? Well, that depends on what you call good and always up for a debate. I wish I knew how to make graphs as I could much easier show what 'bad is bad, good is good, bad is actually good, and so on and so forth." LOL. BTW: the terms bad and good is when torque curves are critiqued heavily. Not something we worry about in a massive beast going thru / on the water.

What are you going to do on the exhuast side? Still out the side, or try to go out the transom. What kind of speed are you getting now? I have 2 spare bravos 3s now. So time to up the power also

[QUOTE=SB;4450253]Great, on all 3 subects.

What flame arrestor are you using ?[/QUOTE

Duh I said air cleaner...K&N flame arrestor 14x4

Come on, I was informed 700 was easy on my combo! NOT

You have nothing to worry about, great job! I wish I had some of this info when I built by engines... I am the first person ever probably looking forward to refresh time to change it all. Go Bob! Thx for nothing

SB- It was explained to me that on a computer controlled dyno; programmed to pull a certain rpm/sec, the computer sees the torque dip and releases the water brake to allow engine to continue on the preprogrammed pull rate. So in essence when you see the dip not only are you getting a reduction in the torque output of the engine, but also the dyno is "helping" the engine by reducing the load to stay on track.

I was running 51 @ 4950 wot/cruise 40 @ 4000 with 30p props 540", 502 mpi intakes, worn out main bearings, scored cranks and several valves not sealing.

I looked at going out the transom but just not enough height above water to make it work so I "fixed" the stock water lift mufflers ;)

[ATTACH=CONFIG]556462[/ATTACH][ATTACH=CONFIG]556463[/ATTACH]

If GM roller lifters work with this size cam, why are guys spending more than 2x's the money on Morel and Johnson lifters in this kind of build? I get it on big dollar full out high RPM builds, but this is normal guy stuff and I'm curious why more don't use the GM lifter?

Marketing

Thanks for the info. I thought I was crazy with my slip numbers, but there identical to yours. I have a hard time believing that it was supposed to run 53 stock new.

[QUOTE=Aqua Banshee;4450333]Thanks for the info. I thought I was crazy with my slip numbers, but there identical to yours. I have a hard time believing that it was supposed to run 53 stock new.[/a
Agreed no idea how they claim 53 with 415 horse per side seems impossible.

Thanks for sharing your results. Kinda narrows down what mine should be at now that I swapped heads. Damn near identical builds.

More power for us "Whale" drivers never hurts:daz:

What cam was in your 540s? Have you run the exhuast with the mods yet? Sorry for the high jack.

Crane 168791
Not yet but I'm expecting it to flow a bit better than stock

You need a couple of Parvey motors.Lol. Just kidding.

Nice respectable build especially considering out of the box 308's. Job well done. Awesome torque all the way through. Thumbs to you. Now just curious as to your decision with your cam choice over the 741 being so close yet different? More than like the peak rpm/hp. Regardless great choice.

Did you end up more? Less? Or about what you aiming for?