How much power?

[Tomas Wallin]

Hi all,

Anyone have an estimate on how much power/torque and rpm my rotating assy would take?



The engine specs:
Block: Merlin II 509ci
Crank: Callies 4" stroke
Rods: Manley H-Beam
Pistons: JE blower pistons (757F) 4.5" Bore
Piston rings: Total seal TNT gapless top
Cam: Marine Kinetics Hyd roller
242º/250º @ .050" / .646"/646" lift valve / 112LSA
Wot RPM: 5800rpm
Heads: GM 188 ported chambers (ARP studs)
Head gaskets: FelPro MLS
C/R: 8.3
Valves: 1.88/2.25
Valve Springs: ISKY 8205PLUS
Rockers: Jesel Comp Series 1.7
Intake: BDS Blower intake
Intercooler: Superchiller
Blower: BDS 8-71
Boost: 8PSI (6.1% overdrive)
Carbs: 2x Holley 9022 800cfm
Jetting: 74/89 2.5PV Boost referenced (for the moment)
Ignition: MSD 6
Distributor: MSD 84891 Crab cap
Exhaust: Stainless Marine Gen III with 4.5" dry tails
Fuel: 93octane
Fuel system: Pickup tube ID: 5/8" / AN-10 from PU to A-1000 pump / AN-8 to fuel regulator / AN-8 to the fuel block and hard tubes to the carbs / AN-8 return with fuel cooler to the fuel filter. It is steady through the rpms.
Fuel pressure: 8-9PSI

[Mrhorsepower1]

1000 - 1050 HP would be safe

[Tomas Wallin]

1000 - 1050 HP would be safe

Thanks Dean!

And the follow up question... How much would it be possible to get out of GM 088 heads and the rest of the setup with changing the boost and possibly the cam and running 93 or 94 octane.


Perhaps Mr Bob Madara would like to chime in since you made the present cam?!

[Tomas Wallin]

Thanks Dean!

And the follow up question... How much would it be possible to get out of GM 088 heads and the rest of the setup with changing the boost and cam and running 93 or 94 octane.


Perhaps Mr Bob Madara would like to chime in since you made the present cam?!

TTT

[rockfish71]

The 088 heads are good and even better with a little port matching up everthing they have a very good 325 cfm runner alot of people think aftermarket.. it's got to be better not aways you need the best for what your doing alot of engines here are only spinning 5700 or less and putting on all the biggest flowing everything and getting very sh!ty performance you have to optmize the airflow for the rpms your running and you will see lot's of good performance. when I state good performance I mean a storge pull from idle to wot.... not just wot

[Tomas Wallin]

Hey Rockfish,

Thanks for your reply, you're definately correct. It's not the best parts that works best - it's the best parts for the application that works best.

Would it be possible to get to 900HP with just adding more boost and retuning the carbs or will the increased boost cause detonation before I get to the 900 mark? On 93 octane of course. My dynoguy was a bit disappointed that I didn't have more than 8PSI since he thought I would get 900 without any problems - but I'm not all that convinced of it...

Is there a way to calc how much every added PSI of boost will add to the HP (as long as everything works fine without detonation etc). I guess I would better get a knock sensor if I would go that route...

[PatriYacht]

Because you have low compression and an intercooler, I would think it would be safe to increase boost to 10 lbs. You're getting 50-60 hp per 2 lbs. of boost already so that's about how much more I would expect from the pulley change. The GM heads flow poorly compared to any of the new aftermarket heads. Changing to a set of properly set up Iron Eagles would probably get you to 900 hp. Good luck.

[Geronimo36]

900 hp on Iron heads?

[Tomas Wallin]

Yeah! But I will keep my 088's...

We'll see what the economy says later on, if I will bring it to the dyno once again and use the whole day to tune instead of messing around with things that wouldn't work the way they should (like last time)

[PatriYacht]

I just assumed that you were boating in salt water and would want to keep running iron heads.

[Geronimo36]

I dunno folks... I'd like to hear from Mrhorsepower but I don't know if you could "reliably" make 900hp with a 509" and iron heads, even with an intercooler on 93 octane. Maybe on race gas...but why. Whaddya think Dean?

[Tomas Wallin]

I dunno folks... I'd like to hear from Mrhorsepower but I don't know if you could "reliably" make 900hp with a 509" and iron heads, even with an intercooler on 93 octane. Maybe on race gas...but why. Whaddya think Dean?

Well, I don't know for sure. It would be very interesting to hear what the engine gurus has to say about it, and as you said - why.

[Chris]

I can't imagine 088's flowing enough to support that much horsepower- especially on the exhaust side. Plus the iron heads lose the thermal benefit of the aluminum version, inviting preignition- even with a chiller.

Close to 2hp/cid? That's pushing it.

[Tomas Wallin]

I can't imagine 088's flowing enough to support that much horsepower- especially on the exhaust side. Plus the iron heads lose the thermal benefit of the aluminum version, inviting preignition- even with a chiller.

Close to 2hp/cid? That's pushing it.

Here's what the heads in question look like. They are also lightely port matched to the intake and exhaust.

The chambers is close to 120cc, that's about 2 more than the original 118.

[Chris]

Thge head bolt is in the way on the exhaust- there's just not enough material to open them up enough to flow the kind of flows you'd need to make those sort of numbers. The exhaust ports are raised on all the aluminum heads- to lessen the effect of that hard bend on flow.

And the iron head doesn't have near the thermal efficiency- which leads to detonation. That should be worth 75+ hp.

My guess is Dean was referencing how much HP the bottom end would handle.

[Tomas Wallin]

Thge head bolt is in the way on the exhaust- there's just not enough material to open them up enough to flow the kind of flows you'd need to make those sort of numbers. The exhaust ports are raised on all the aluminum heads- to lessen the effect of that hard bend on flow.

And the iron head doesn't have near the thermal efficiency- which leads to detonation. That should be worth 75+ hp.

My guess is Dean was referencing how much HP the bottom end would handle.

Yes Dean was refering to the bottom end.

I'm at 825HP@5800 and 815ft-lbs@4000 with 8PSI today.

[mdgperf]

Sounds like you got some good power from that combo,I think you would need to add cubes and better heads for reliable hp in the 900hp range on pump fuel,a solid roller could possibly add some hp but reliabilty could suffer,i know the cam companys are working on some different solid grinds and better lifters,could make solid rollers a better option in the future

[Tomas Wallin]

Sounds like you got some good power from that combo,I think you would need to add cubes and better heads for reliable hp in the 900hp range on pump fuel,a solid roller could possibly add some hp but reliabilty could suffer,i know the cam companys are working on some different solid grinds and better lifters,could make solid rollers a better option in the future

Yes, the bottom end is your recipe.

I really like the combo as it is now but would like to optimize everything to get the absolute most out of it and still be reliable.

Do you remember what crankshaft it has. I couldn't find any proper serial# on it. Just Callies Stealth 39175 and Stealth is some special metal treatment as far as I have found out. You told me back then that the crank was the one better than DragonSlayer?!

[AGITATOR]

used to run that combo on my american offshore it made 890 hp at 6000 rpm and 850 ft of torque with a flat torque curve it was a good combo we ran 8 psi boost twim 900 cfm carbs non intercooled 32 deg timing 14 deg curve all in at 2500 rpm

[Tomas Wallin]

used to run that combo on my american offshore it made 890 hp at 6000 rpm and 850 ft of torque with a flat torque curve it was a good combo we ran 8 psi boost twim 900 cfm carbs non intercooled 32 deg timing 14 deg curve all in at 2500 rpm

Did you have GM Iron heads and pump gas on that engine?