I just cant leave anything alone !!!
10-05-2022, 08:05 AM
#81
VIP Member
VIP Member
In latest news... I just dropped $2k on a closed cooling system. It's only a half system and doesn't touch the manifolds... but at least the engine wont have scummy water running through it and it wont freeze over the winter.
https://www.hardin-marine.com/p-1003...lf-system.aspx
Next will be a better set of manifolds with dry joints. Still shopping for the right system. Looking at Stainless Marine and Dana. Cannot swing $8k+ on CMI stuff. $3500 dry joint manifolds will suffice.
I never liked the VP and Mercruiser wet joints. Almost lost my last (merc) motor because of previous owners maintenance neglect. Had water in several cylinders one day after running on muffs in the driveway. Figured it out the next day when the motor was hydrolocked. Pulled all plugs, spun it over to push water out and fogged all cylinders. Resurfaced manifolds/risers and replaced gaskets and it was good as new. Motor wasnt hurt and still ran strong.
https://www.hardin-marine.com/p-1003...lf-system.aspx
Next will be a better set of manifolds with dry joints. Still shopping for the right system. Looking at Stainless Marine and Dana. Cannot swing $8k+ on CMI stuff. $3500 dry joint manifolds will suffice.
I never liked the VP and Mercruiser wet joints. Almost lost my last (merc) motor because of previous owners maintenance neglect. Had water in several cylinders one day after running on muffs in the driveway. Figured it out the next day when the motor was hydrolocked. Pulled all plugs, spun it over to push water out and fogged all cylinders. Resurfaced manifolds/risers and replaced gaskets and it was good as new. Motor wasnt hurt and still ran strong.
To my knowledge, that's how all closed cooling systems work. The coolant runs through the engine while lake water runs through the heat exchanger and out through the manifolds/headers, cooling them in the process. Somebody correct me if I'm wrong....
Thanks. Brad.
(937)545-8991
10-05-2022, 08:10 AM
#82
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Thread Starter
Dragracer,
To my knowledge, that's how all closed cooling systems work. The coolant runs through the engine while lake water runs through the heat exchanger and out through the manifolds/headers, cooling them in the process. Somebody correct me if I'm wrong....
Thanks. Brad.
(937)545-8991
To my knowledge, that's how all closed cooling systems work. The coolant runs through the engine while lake water runs through the heat exchanger and out through the manifolds/headers, cooling them in the process. Somebody correct me if I'm wrong....
Thanks. Brad.
(937)545-8991
10-05-2022, 08:12 AM
#83
Registered
10-05-2022, 08:13 AM
#84
Registered
Thread Starter
Dragracer,
I also wonder about the 90DEG bends in the exhaust routing that is usually implemented with side exhaust. I would think they would induce backpressure that would be unwanted for a higher performance engine. We had them in our Rinker, and I often wondered if they weren't holding the engine back some.
Thanks. Brad.
(937)545-8991
I also wonder about the 90DEG bends in the exhaust routing that is usually implemented with side exhaust. I would think they would induce backpressure that would be unwanted for a higher performance engine. We had them in our Rinker, and I often wondered if they weren't holding the engine back some.
Thanks. Brad.
(937)545-8991
I only ran 4" exhaust on my street legal drag cars and they were low 8-sec cars with nitrous and 1000+ hp.
10-05-2022, 08:15 AM
#85
Registered
Thread Starter
I agree with the better sound out the rear... and yeah... there is just no way to cleanly route pipes straight out the back of that style transom. There is nothing flat or square about it.
10-05-2022, 11:47 PM
#86
Platinum Member
Platinum Member
Stay away from huge cubic inches and monster torque, or you'll mangle your outdrive.
A 502/509 is a great combo because the large bore doesnt shroud the valves.
550 hp at 5600 is an easy target.
This is likely the upper limit for yoyr outdrive.
A 572 or 632 will make another 100+ ft*lbs of torque which will be tough for your outdrive to absorb. If you go that route, you will likely have real-world experience on exactly what the breaking point is for a DPX
A 502/509 is a great combo because the large bore doesnt shroud the valves.
550 hp at 5600 is an easy target.
This is likely the upper limit for yoyr outdrive.
A 572 or 632 will make another 100+ ft*lbs of torque which will be tough for your outdrive to absorb. If you go that route, you will likely have real-world experience on exactly what the breaking point is for a DPX
The following 2 users liked this post by mcollinstn:
articfriends (10-06-2022), SB (10-06-2022)
10-06-2022, 05:04 AM
#87
Registered
Thread Starter
Stay away from huge cubic inches and monster torque, or you'll mangle your outdrive.
A 502/509 is a great combo because the large bore doesnt shroud the valves.
550 hp at 5600 is an easy target.
This is likely the upper limit for yoyr outdrive.
A 572 or 632 will make another 100+ ft*lbs of torque which will be tough for your outdrive to absorb. If you go that route, you will likely have real-world experience on exactly what the breaking point is for a DPX
A 502/509 is a great combo because the large bore doesnt shroud the valves.
550 hp at 5600 is an easy target.
This is likely the upper limit for yoyr outdrive.
A 572 or 632 will make another 100+ ft*lbs of torque which will be tough for your outdrive to absorb. If you go that route, you will likely have real-world experience on exactly what the breaking point is for a DPX
I think it makes 525hp on stock manifolds... so if I upgrade to decent manifolds too... I think he says 540hp+
Still lots to consider... and I appreciate everyone's input. I dont want to beat this topic to death so I will let the thread fall down the page unless folks want to keep bouncing ideas around.
Last edited by Dragracer_Art; 10-06-2022 at 05:07 AM.
10-06-2022, 05:07 AM
#88
Registered
Thread Starter
I did finally get my GA registration and numbers yesterday... so the purchase from Illinois/LOTO is now sealed and complete. Seller did not have title in hand when we bought it (bank owned) so it's always a crapshoot how that kind of deal goes. I usually run from any deal like this (no title in hand) but the extra effort and patience was worth it. The boat is mint/garage kept and the sellers were top notch folks, so that went a long way with me.
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the deep (10-06-2022)
10-06-2022, 05:16 AM
#89
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Thread Starter
Techman and Icdedppl got it right.
Only thing is, is to check that your WOT rpm is near the top end of your recommended rpm for that motor. Otherwise it will feel more sluggish than it should. Very simple idea, but so many dont understand that concept, or have never even checked it. But chances are what you have is correct.
Only thing is, is to check that your WOT rpm is near the top end of your recommended rpm for that motor. Otherwise it will feel more sluggish than it should. Very simple idea, but so many dont understand that concept, or have never even checked it. But chances are what you have is correct.
