my new motor

[bajabob 718]

wt do you think?????:bigear:

[MarylandMark]

I think I need glasses but the graph looks like it looks good!

[Griff]

I've got a 24inch monitor and can't hardly read chit on it

[jhenrie]

The motor may be good to go but buy a new camera.

[Rookie]

wt do you think?????:bigear:

Did you redo your....I think a 540?

[bajabob 718]

sorry about the picture i try to make bigger it is not working for me. rookie yes i redone the 540 and made it a lot better

[Trim'd Up]

What were the peak numbers? I guess my eyes aren't good enough.

[bajabob 718]

i hope this come out better

[bajabob 718]

here my motor on the dyno trying the spacers that go under the carb . they do work

[jeffswav]

Did they check that with wideband or narrowband O2? Looks a little lean at spots. I have mine at 12.5 in the higher RPM range. Are you planning on running it at peak RPM? 6100 RPM is pretty high for a Bravo Drive. Even if you only run 5500 RPM that is still really good power. How does it Idle? I used RMbuilder for my cam and I was blown away by the power and drivabillity.

[bajabob 718]

jeff i am not shore on the band use . i am prop my boat at 5500rpm . rmbuilder is a real nice guy he no alot about cams i talk to him i got good info from him . how did your motor come out

[jeffswav]

jeff i am not shore on the band use . i am prop my boat at 5500rpm . rmbuilder is a real nice guy he no alot about cams i talk to him i got good info from him . how did your motor come out

I have a 489 stroker with large ovals heads and Holley MPI with wideband O2. When I switched from the (performance) flat tappet cam to the Roller I gained 5MPH and better idle. I used the Isky springs and Moral lifters. Bob said to expect 500HP, I think I was about 450 before the cam swap. I think I gained at least 50HP. He set my cam up to make peak power at 5400 RPM. I tried a few props after the upgrade. I could pull a 21 pitch prop over 5600 RPM, the 23 pitch will pull 5400 RPM and my labbed 25 pitch pulls 5000 with the best speed of 70MPH. I am raising the x dim up 3" this winter. My propshaft is 8" below now that will raise it to 5".

[bajabob 718]

jeff that great70mph . my old motor .i did 66.6 gps 71on dream speedo. now with this 540 i am over 80mph i can t wait for summer .

[Geronimo36]

Don't mean to bear bad news or pick on the setup but the cam seems too big to me. Torque peaked at 5300 rpms, that's very high for a boat engine, even naturally aspirated...

Anyone else?

[jeffswav]

Don't mean to bear bad news or pick on the setup but the cam seems too big to me. Torque peaked at 5300 rpms, that's very high for a boat engine, even naturally aspirated...

Anyone else?

I agree, you want your peak HP at about 5500 not at 6100. If it were mine I would get a cam from Bob. I went through all of this before, cut your losses on the cam and get one that works best in your RPM range. Just my .02 cents.

[Geronimo36]

Peak torque is usually 1000 rpms lower than your peak HP and you want to get you PK tq about 1k lower than your target RPM range. If you plan to run the engine at 5500 rpms and pk torque is at 5300 you're going to be loading the engine which could cause detonation and possibly some blown bravo drives.

[JFM]

Good to see ya got the motor back together again. Hope that it is better for you this time.

[Rookie]

If you plan to run the engine at 5500 rpms and pk torque is at 5300 you're going to be loading the engine which could cause detonation

I have to agree with Geronimo, you will be loading the engine pretty hard. I saw twin 496's (stroked 454) die an early life cause the guy propped it at or just below peak torque. The engine was losing power, after tear down the engine looked like it had 500 hard hours on it.

I would prop it to 5800-5900 it will be a lot easier on the engine in the long run.

Your dyno sheet looks almost identical to my dyno sheet, you seem to be on the low side for torque on a 540. What heads are you running and any work to them?

[Raylar]

I would agree with others here, that cam you have in that engine seems to be to big on the top end and running that setup at 5500rpms will be so to speak lugging the engine that far below the HP peak. The peak toque should be down around 4300 to 4500 rpms, not at 5500rpms. The duration numbers must be really large on this cam and I suspect some potential reversion issues at a decent idle rpm??

Good Luck with your engine project.

Best Regards,
Ray @ Raylar

[Pismo10]

Seems a little more automotive.