Blackmax/xr2 electrics

Dan · 04-08-2005, 08:04 PM

Spoke to Greg at GB Watersports today (as recomended ) trying to see what options I have to get a bit more out of the 150. He has suggested trying to get hold of a bust up XR2 and swapping the electrics (and other bits)over as in the XR2 its 16 (amps/olhms cant remember what he said now) as in the blackmax they are 40. Is this relatively simple to do then, do I just swap the corisponding components over?

Captain Chaos · 04-08-2005, 08:07 PM

i would have thought so. and its amps. The theory being that your drawing less power from the powerhead to run all the auxilieries (which in ap21 is next to feck-all anyway) and allowing more of it to rotate ya prop.

Dan · 04-08-2005, 08:10 PM

Even I can do that then!!!

Cheers Captain

JamesM · 04-08-2005, 08:18 PM

Chaos is correct ish because if the battery is fully charged and your not taking much current from the system (i.e trimming up and using tabs and powerlifts all at the same time) then the demand on the charging circuit will be less than 16amps anyway. So whether you have a 16 amp capable charging circuit or a 40 amp capable charging circuit if the demand is say 8 amps then the losses will be the same with either. However the 40amp setup is alot heavier than the 16 amp setup and therefore less rotating mass means lower losses so more power output. Also when you rev the motor the crank flexes at the top due to the weight of the flywheel and stator, with a 40 amp setup its not advisable to rev your motor much past 6000rpm. With the lighter 16 amp setup you can rev to over 7000rpm even more if you get the ally flywheel from a 2.5 260.

JamesM · 04-08-2005, 08:24 PM

All that being said with the porting on a 150 I would have thought the power would tail off fairly quick after 6000rpm I might be wrong though. The porting on a 200 is good for upto about 7000rpm. Also 7000rpm is the upper limit for the cast pistons that are used in the non race motors.

Dan · 04-08-2005, 08:34 PM

Cheers gents. I`ll make some calls tomorrow.

Taz · 04-08-2005, 08:41 PM

Quote:

Originally posted by Dan
Even I can do that then!!!

Cheers Captain

Ut oh somethings gonna blow up!

MrRob · 04-08-2005, 08:45 PM

Hey Johnny. I was told the Rev limit of my promax was 6800rpm. (told this by mutznuts who i bought it from) If I changed it from a 40amp to a 16amp + fitted a MAD EFI light weight flywheel how much higher would I be able to rev?

Taz · 04-08-2005, 09:23 PM

Quote:

Originally posted by MrRob
Hey Johnny. I was told the Rev limit of my promax was 6800rpm. (told this by mutznuts who i bought it from) If I changed it from a 40amp to a 16amp + fitted a MAD EFI light weight flywheel how much higher would I be able to rev?

Ut oh not mutznutz

JamesM · 04-08-2005, 09:26 PM

Dunno. I dont know whats in a promax. Is it defo a 40 amp on that one.

Dan · 04-08-2005, 09:32 PM

Quote:

Originally posted by Taz
Ut oh somethings gonna blow up!

Talking of me busting things, hows your cavitation plate!!

Dean21 · 04-08-2005, 09:42 PM

Taz · 04-08-2005, 09:52 PM

Quote:

Originally posted by Dean21

Thats right dean dont even go there.
My cavitation plate was due to a act of god

Dean21 · 04-08-2005, 09:55 PM

Quote:

Originally posted by Taz
Thats right dean dont even go there.
My cavitation plate was due to a act of god

I wasnt planing on goinin there but...
expensive thngs these acts of god

TheMutzNuts · 04-08-2005, 09:56 PM

Quote:

Originally posted by MrRob
Hey Johnny. I was told the Rev limit of my promax was 6800rpm. (told this by mutznuts who i bought it from) If I changed it from a 40amp to a 16amp + fitted a MAD EFI light weight flywheel how much higher would I be able to rev?

dude u got a 16 amp stator!if your going to rev it its advisable to remove the oil injection, at higher rpm they sometimes fail to deliver enough oil.
you could get a brucato ecu which has a 15k rpm limit and you can also alter the fuel curv from in the boat.
you can also get a mad efi which would give it some extra horses.
the 225 promax is the same block as the 260 efi but with smaller ports,lower revlimiter and oil injection,all these things can be modified to the same spec as the 2.5efi and past if thats the way you want to go.
JBD,Roofer Jon correct me if any of this is incorrect

Taz · 04-08-2005, 09:58 PM

I know one minute you driving along and bang there goes your engine ask burty and roofer it reallyu hurts your wallet

Burty · 04-08-2005, 10:42 PM

Quote:

Originally posted by Dan
Even I can do that then!!!

Cheers Captain

You still need to remove the flywhell which aint easy!

Taz · 05-08-2005, 08:02 PM

Flywheel puller comes in handy there!