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Discussion Starter #1
I dont think my boat is running the correct rpms for my setup. I have a fresh jacuzzi wj w/ an b impeller snd a 460 bored .030 with keith black dish pistons. Ported d0ve-a heads, stealth intake. Trick flow pushrods with comp roller rockersCrane 288 commander cam. 850 dp. Msd distributor with a msd box. It only turnd 45-4600 rpm max. Problem id I was turning that before when it was stock. I have swapped tachs already. What could be the problem? Camshsft timing maybe?
 

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I dont think my boat is running the correct rpms for my setup. I have a fresh jacuzzi wj w/ an b impeller snd a 460 bored .030 with keith black dish pistons. Ported d0ve-a heads, stealth intake. Trick flow pushrods with comp roller rockersCrane 288 commander cam. 850 dp. Msd distributor with a msd box. It only turnd 45-4600 rpm max. Problem id I was turning that before when it was stock. I have swapped tachs already. What could be the problem? Camshsft timing maybe?
Good chance it could be a timing issue.
 

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I dont think my boat is running the correct rpms for my setup. I have a fresh jacuzzi wj w/ an b impeller snd a 460 bored .030 with keith black dish pistons. Ported d0ve-a heads, stealth intake. Trick flow pushrods with comp roller rockersCrane 288 commander cam. 850 dp. Msd distributor with a msd box. It only turnd 45-4600 rpm max. Problem id I was turning that before when it was stock. I have swapped tachs already. What could be the problem? Camshsft timing maybe?
That would be the first thing to check for sure
Put a degree wheel on it and get your cam card out
Lot of mistakes happen on the 429-460 here
 

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Need more info!!! Hull type, weight, loader style if any?
I agree.
Lets try to be realistic here. If the timing is off due to a "replacement" timing set that has a retard built in it like most "replacement" Ford sets do, and the OP didn't use a name brand performance T set, what is the very very best super optimistic RPM gain you could expect to see if the timing was "corrected"?

Remember, MOST el cheapo replacement sets retard the timing which isn't exactly detrimental to turning RPM.
I wonder what pie in the sky RPM the OP was hoping to turn.



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I dont think my boat is running the correct rpms for my setup. I have a fresh jacuzzi wj w/ an b impeller snd a 460 bored .030 with keith black dish pistons. Ported d0ve-a heads, stealth intake. Trick flow pushrods with comp roller rockersCrane 288 commander cam. 850 dp. Msd distributor with a msd box. It only turnd 45-4600 rpm max. Problem id I was turning that before when it was stock. I have swapped tachs already. What could be the problem? Camshsft timing maybe?
What do you honestly predict this motor should make for horse power and where is it (peak HP) made (RPM) given the combination you have described and assembled ?
 

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I agree.
Lets try to be realistic here. If the timing is off due to a "replacement" timing set that has a retard built in it like most "replacement" Ford sets do, and the OP didn't use a name brand performance T set, what is the very very best super optimistic RPM gain you could expect to see if the timing was "corrected"?

Remember, MOST el cheapo replacement sets retard the timing which isn't exactly detrimental to turning RPM.
I wonder what pie in the sky RPM the OP was hoping to turn.
Well Bob, in under a half hour I could top stop the piston verify cam timing and have a TDC mark to set timing from

Its just a starting point for me. Before chasing my tail. I would verify the basics are in place first

Seen a few people f- up multi key timing chains in the past or had the dampener slip and the timing marks are off when setting the dizzy

Things that you are supposed to catch when building the motors vs assembling parts and hoping it works out
 

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I thought with Ford's you just throw some parts in a box..shake it and run what comes out?
 

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I dont think my boat is running the correct rpms for my setup. I have a fresh jacuzzi wj w/ an b impeller snd a 460 bored .030 with keith black dish pistons. Ported d0ve-a heads, stealth intake. Trick flow pushrods with comp roller rockersCrane 288 commander cam. 850 dp. Msd distributor with a msd box. It only turnd 45-4600 rpm max. Problem id I was turning that before when it was stock. I have swapped tachs already. What could be the problem? Camshsft timing maybe?
Was the pump rebuild with the engine rebuild? If it was fairly worn prior to bebuild, tightening up the pump likely countered some of the rpm increase you would have seen with the added HP.
 

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Discussion Starter #13
It is a 21 omega open bow with fresh jacuzzi wj. No loader.has Pd. Ride plate. Also the timing set is a cloyes double roller with 3 keyways set. Just seems off. Alot of money in the motor with no gains. Expected hp is 450ish. Btw I am running logs.
 

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Discussion Starter #14
Pump was rebuilt during the rebuild. I am looking for 5100 rpms ish. Is my setup capable of this? If not I believe my cam is the limiter. What do u guys recommend
 

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Pump was rebuilt during the rebuild. I am looking for 5100 rpms ish. Is my setup capable of this? If not I believe my cam is the limiter. What do u guys recommend
If the engine you built is capable of making an honest 450 HP at 5k then your clearly down on power as you suspect , could be a simple tuning issue ,think you indicated the pistons are dished may be the wrong cam choice for the compression ? do you recall what the compression ratio ended up ? might have missed it but did you degree the cam ? for reference sake a production 460 marine motor in the 70s made around 320 HP , according to your 4500/4600 rpms your currently making around 350 HP (Jacuzzi B will develop much like a Berkeley A)

rpm hp
4400 304.77 363.65
4500 326.03 380.36
4600 348.25 397.46
4700 371.46 414.93
4800 395.68 432.77
4900 420.92 450.99
5000 447.23 469.59

BTW not sure what your cam card says but this is what I found
LIFT

Intake-522

Exhaust-530

ADV DURATION
Intake-288
EXHAUST-292

RPM RANGE
2500-5500
 

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Pump was rebuilt during the rebuild. I am looking for 5100 rpms ish. Is my setup capable of this? If not I believe my cam is the limiter. What do u guys recommend
I think that you are on the right track with the cam being the limiting factor if your timing set-up is correct. I think your cam should be above 600 lift to get more performance, but you should talk to one of the cam guys here on the boards for best recommendations. You might even think about after the cam change, going bigger on the carb.

You need to let that big dog eat.

Also, with 4600 as your max RPM in a tight pump, I would bet you picked up MPH from before the rebuild.
 

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Another thought, if you degreed the cam correctly, what do you have the timing set at? I would think that 36* would be a good starting point.

Buy the way, BigSteve did have a good point on checking the multi index key.
 

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What is the static compression of the mill?

Why such a small cam? Remember, it's just a shiny air pump.

Check the simple stuff first. CAM TIMING..


And if you rebuilt the pump while the engine was out then you have no control to base RPM from accurately.

Did you happen to GPS the boat before all the work? And after?

The pump is more than likely absorbing more power than before.
 

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5100 w/logs

I think that you are on the right track with the cam being the limiting factor if your timing set-up is correct. I think your cam should be above 600 lift to get more performance, but you should talk to one of the cam guys here on the boards for best recommendations. You might even think about after the cam change, going bigger on the carb.

You need to let that big dog eat.

Also, with 4600 as your max RPM in a tight pump, I would bet you picked up MPH from before the rebuild.
Bigger??? I would suggest SMALLER, maybe 750 and jet it for correct a/f ratio... You can feed a big dog all day, but that same dog needs to shit, and shitting through log exhaust could create some heavy duty constipation.... There is no way that combination needs that 850 carb....
Ray
 

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Discussion Starter #20
I can say this much. The boat pulls 58 diverter slightly up letting it air out but porpouses like a mother. Diverter down is 51. Max timing is 32. Initial 14. Timing chain set on the circle on cloyes. Ive pkayed with distributor timing and jetting, spacers and no spscers. Its at its max. As for prior max speed I cannot compare as it had a c impeller and now has a b jaccuzzi. I wanna get this squared away though so I csn figure out the shitty ride. Thinkin a shoe next
 
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