HP500 rebuild...what next?
#1
Thread Starter
FIERCE ALLEGIANCE
Joined: Jun 2003
Posts: 1,207
Likes: 0
From: West palm Beach, FL & SML VA
Here's where we're at: Rebuilding both Gen 6, HP500 motors with a new set of Dart Iron Eagle 308cc heads (Inconel Valves) Crane Cam 168731 (copper). Already has a new Dart Intake on both. The only 2 areas needing attention is Carbs (so far just stock Holly 800, jets supposedly replaced from size 70 to size 80 but this doesn't make sense) and Exhaust so far just stock GILS with a weird NRS exhaust tube.
The question is...what's next?
I have not replaced the original ignition and figured a new MSD (6M-2, MSD8560 & Soft Touch Rev Control 8768) was next for this. Won't this be necessary in order to get everything synced up correctly and to increase the rev limiter?
The Holly 800 I'd like to just keep but didn't know what problems I'm going to face or if a 900-950+ was necessary.
And as for the GIL, I know my choices is GIL or CMI and would prefer CMI, but I'd like to just get on the water this year and look at a winter project for exhaust. I'd like to have silent choice but do not want reversion. I'm not counting ponies just want the most out of a reliable set up. OSO has been great source of information... keep it coming.
The question is...what's next?
I have not replaced the original ignition and figured a new MSD (6M-2, MSD8560 & Soft Touch Rev Control 8768) was next for this. Won't this be necessary in order to get everything synced up correctly and to increase the rev limiter?
The Holly 800 I'd like to just keep but didn't know what problems I'm going to face or if a 900-950+ was necessary.
And as for the GIL, I know my choices is GIL or CMI and would prefer CMI, but I'd like to just get on the water this year and look at a winter project for exhaust. I'd like to have silent choice but do not want reversion. I'm not counting ponies just want the most out of a reliable set up. OSO has been great source of information... keep it coming.
#5
Registered
Joined: Oct 2000
Posts: 532
Likes: 0
From: Fells Point MD
I kept my Tbolt and switched to the V6 module and MSD rev limiter. No sweat, runs to 5800 and I still have the V8 module in the boat if something fails. Just need to change timing.
#7
The 800 should be plenty of carb. As for jet sizing, stock jets are not 70's and jetting is staggered. Here are the stock jet sizes.
Pimaries--port-81, starb-75
Secondaries--port-89, starb-93
Pimaries--port-81, starb-75
Secondaries--port-89, starb-93
#8
Go to the Crane 741 cam. The 731 is smaller than some of the HP cams. The new HP 525 cam has the same lobes as a 741 except it is ground with a 114 lsa instead of a 112 lsa.
#9
Thread Starter
FIERCE ALLEGIANCE
Joined: Jun 2003
Posts: 1,207
Likes: 0
From: West palm Beach, FL & SML VA
Originally Posted by PatriYacht
Go to the Crane 741 cam. The 731 is smaller than some of the HP cams. The new HP 525 cam has the same lobes as a 741 except it is ground with a 114 lsa instead of a 112 lsa.
#10
They changed the part no. I'm not sure what it is now. Do a search or maybe someone can chime in. Or use the new 525 cam. Again the part no has been listed here before, have to try a search.



