this really sucks?
03-17-2006, 06:13 AM
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this really sucks?
on 35 1998 lightning iam very unhappy with the performance after my engine upgrade this is why.
before the upgrade with 1998 tired motors one motor had 90 compression on 2 cylinders the boat ran 72.1 gps full fuel,2 people, spinning 26 hydromotives @5000 rpm wot.
the upgrade was asm, new upgraded crane cam, dart heads, msd ignition, roller rockers, cmi exhaust and a computer reflashing. cost of parts was approx 18,000.00.
heres what the performance is now(it sucks)
between 1/2 and 3/4 fuel,2 people, 26 hydromotives compression is back to 150+ on all cylinders. boat ran 74.4 gps @5000 rpm
water and wind were the same before and after.
the only thing i did not do was change the intake to get more air into the motor. do you guys think this is hindering the new heads and cam from working properly ie creating more hp?
before the upgrade with 1998 tired motors one motor had 90 compression on 2 cylinders the boat ran 72.1 gps full fuel,2 people, spinning 26 hydromotives @5000 rpm wot.
the upgrade was asm, new upgraded crane cam, dart heads, msd ignition, roller rockers, cmi exhaust and a computer reflashing. cost of parts was approx 18,000.00.
heres what the performance is now(it sucks)
between 1/2 and 3/4 fuel,2 people, 26 hydromotives compression is back to 150+ on all cylinders. boat ran 74.4 gps @5000 rpm
water and wind were the same before and after.
the only thing i did not do was change the intake to get more air into the motor. do you guys think this is hindering the new heads and cam from working properly ie creating more hp?
03-17-2006, 07:35 AM
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Re: this really sucks?
Briana
I don't se your suprise, you are spinning the same props at the same RPM ???????? and you actually gained 2mph I find that pretty impressive. Are your rev limiters set at 5000rpm?? I would first try some bigger props, more HP doesn't help if you don't push more water either by more RPMs or higher pitch prop.
Good luck either way
WILL
I don't se your suprise, you are spinning the same props at the same RPM ???????? and you actually gained 2mph I find that pretty impressive. Are your rev limiters set at 5000rpm?? I would first try some bigger props, more HP doesn't help if you don't push more water either by more RPMs or higher pitch prop.
Good luck either way
WILL
03-17-2006, 07:51 AM
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Re: this really sucks?
Originally Posted by 27Fountain
Briana
I don't se your suprise, you are spinning the same props at the same RPM ???????? and you actually gained 2mph I find that pretty impressive. Are your rev limiters set at 5000rpm?? I would first try some bigger props, more HP doesn't help if you don't push more water either by more RPMs or higher pitch prop.
Good luck either way
WILL
I don't se your suprise, you are spinning the same props at the same RPM ???????? and you actually gained 2mph I find that pretty impressive. Are your rev limiters set at 5000rpm?? I would first try some bigger props, more HP doesn't help if you don't push more water either by more RPMs or higher pitch prop.
Good luck either way
WILL
If he's running 26 hydro's from the factory then my guess is the boat came with hp 500's. That was the standard prop/engine combo from the factory for the 35 ex's. He should be able to push those to around 5300 and 80ish mph.
03-17-2006, 08:01 AM
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Re: this really sucks?
Have the motors been given a chance to "run in"? May need to run them a bit to see how they do. Also, how old was the gas and if it was new, is it the "winter formulation"?
03-17-2006, 08:01 AM
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Re: this really sucks?
So what's the story on this boat. What did the boat run before you lost compression - rpm and speed?
I'm surprised it was propped with 26 hydro's if the boat only had 502 mags. My 35 with hp 500's came with the same props.
How much HP are these motors pushing - or suppose to be pushing? What were you expecting out of them?
I'm surprised it was propped with 26 hydro's if the boat only had 502 mags. My 35 with hp 500's came with the same props.
How much HP are these motors pushing - or suppose to be pushing? What were you expecting out of them?
03-17-2006, 08:22 AM
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Re: this really sucks?
this was an upgrade package from arizona speed marine my mechanic did the work.
doesn't higher pitch ie 28 or 30 mean less rpm, i was told basic rule is 1-2 degree is approx 400 rpm loss or gain depending on the way you go.
ex 26deg 4bl @5000
28deg 4bl@4600
24deg 4bl@5400
doesn't higher pitch ie 28 or 30 mean less rpm, i was told basic rule is 1-2 degree is approx 400 rpm loss or gain depending on the way you go.
ex 26deg 4bl @5000
28deg 4bl@4600
24deg 4bl@5400
03-17-2006, 08:29 AM
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Re: this really sucks?
I take hp # gains with a grain of salt
az speed claims my set up should have brought these motors to 515 to 520 at the crank.
i was hoping to get similar performance to 35 with 500hp's which is 80ish.
what type of prop would you guys recommend?
az speed claims my set up should have brought these motors to 515 to 520 at the crank.
i was hoping to get similar performance to 35 with 500hp's which is 80ish.
what type of prop would you guys recommend?
