Would you change anything in this combo? 509 SC Carb
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Would you change anything in this combo? 509 SC Carb
Is there anything you would change right away in this combo to get it more reliable, more HP, better fuel efficiency etc?
The engine is as follows:
Block: Merlin II 509ci
Crank: Callies
Rods: Manley H-Beam
Pistons: JE blower pistons (757F)
Comp: 8-8.5 according to engine builder
Cam: UltraDyne mechanical flat tappet (J3854)
272º/282º Seat duration
238º/248º @ .050"
146º/155º @ .200"
.550"/570" lift valve
.3233"/.3353" lift lobe
114 LSA
15 16 (lobe master #)
Heads: GM 188 Cast iron 118cc open chamber, 325cc intake volume
Head gaskets: FelPro Wire-Loc
Valves: 1.88/2.25
Rockers: Jesel Comp Series 1.7
Intake: Blower intake
Blower: BDS 8-71
Boost: ~5psi
Carbs: 2x Holley 9022 800cfm
Ignition: Mercruiser Thunderbolt 4
Exhaust: Mercruiser/GIL Hi Performance
According to engine builder (MDG Performance) it dynoed at 720-740HP@5600-5700rpm on 91 octane.
Will be switching to and adding:
Exhaust: Stainless Marine Gen III with 5" dry tails
Intercooler: Superchiller
Boost: 8psi
Cam: Hyd roller by RMBuilder
Bigger thermostatic oil cooler
The engine is as follows:
Block: Merlin II 509ci
Crank: Callies
Rods: Manley H-Beam
Pistons: JE blower pistons (757F)
Comp: 8-8.5 according to engine builder
Cam: UltraDyne mechanical flat tappet (J3854)
272º/282º Seat duration
238º/248º @ .050"
146º/155º @ .200"
.550"/570" lift valve
.3233"/.3353" lift lobe
114 LSA
15 16 (lobe master #)
Heads: GM 188 Cast iron 118cc open chamber, 325cc intake volume
Head gaskets: FelPro Wire-Loc
Valves: 1.88/2.25
Rockers: Jesel Comp Series 1.7
Intake: Blower intake
Blower: BDS 8-71
Boost: ~5psi
Carbs: 2x Holley 9022 800cfm
Ignition: Mercruiser Thunderbolt 4
Exhaust: Mercruiser/GIL Hi Performance
According to engine builder (MDG Performance) it dynoed at 720-740HP@5600-5700rpm on 91 octane.
Will be switching to and adding:
Exhaust: Stainless Marine Gen III with 5" dry tails
Intercooler: Superchiller
Boost: 8psi
Cam: Hyd roller by RMBuilder
Bigger thermostatic oil cooler
Last edited by tomas_wallin; 05-03-2007 at 03:58 AM.
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Re: Would you change anything in this combo? 509 SC Carb
Go with a slightly larger cam. I run a 598/610 crane 731 roller in my 509's and at 8 psi I am at 765 hp and over 825 torque
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Re: Would you change anything in this combo? 509 SC Carb
Get yourself an intercooler and a Crane marine ignition.When you say Mercruiser ignition,what do you mean?
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Re: Would you change anything in this combo? 509 SC Carb
I mean a Merc Thunderbolt 4.
Last edited by tomas_wallin; 01-29-2007 at 06:07 AM.
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Re: Would you change anything in this combo? 509 SC Carb
Of course an ignition will help.If you are using a Thunderbolt style your timing is set for a carbed engine.Can you imagine having a multiple spark ignition that you can set the same timing curve of the 600sc Merc, 800sc,525sc,900 sc and a heap of others with the turn of a switch.It also has a boost retard function and rev limiter built in.It comes in one box and is plug in to your existing harness.But best of all shipping doesn't cost you a fortune like it does me.Summit racing have them.They are about $291.Almost free.
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Re: Would you change anything in this combo? 509 SC Carb
Dave has been doing this for many years, I would not change anything, leave it set up as he gave it to you. He spent the time tuning it on a Dyno, so if you change it, you have lost that. I know he sets up his engines on the conservitive side but they live.