Reply With QuoteWow, so everyone is running them straight out the box. I wonder why they all say not for marine use?
Now the debate is whether to go with a ZZ502 or the Merlin. Both are $7500. Any ideas?
I agree on the crate motors. I have a freind with a 502/502 crate motor in a 23ft wellcraft nova. The motor has over 200 very hard hours on it to date and the only thing that has been changed is the oil. The wellcraft runs an honest 70mph on the gps and makes those 70 to 80mph speedo bajas suck hind tit. When I can aford one, the crate motor will get my money. Taylorman i included bill mitchells link here. You can get a free catalog and by direct from him if you want to.Bill Mitchell Racing Engines (http://www.theengineshop.com/) Let us know if you get one.
Wow, so everyone is running them straight out the box. I wonder why they all say not for marine use?
Now the debate is whether to go with a ZZ502 or the Merlin. Both are $7500. Any ideas?
[QUOTE=Dragboats]Certainly not an expert tho my experience has shown when I did some research: Heads and cams typically are set up for a different torque curve. A marine engine must develop most of its torque on the low end of throttle range. This allows for the ability to use a single gear transmission system. Brass freeze plugs instead of steel and carburetors with J bowls... Marine head gaskets can be unique as well. Marine can also mean to be used in salt water so then you have a whole host of things that would be different from a car motor mostly bolt on items. Its all about parts matching for the application, a boat is a asummed that you will be driving the engine harder than you would a car, so maybe the parts used should reflect that use. These crate motors when they say "not recommended for marine use" I feel is taking into consideration that one may put it in salt and or enclosed engine compartments with a non coast guard approved induction system that may come with some of the crate motors. Anyway just my 02. I have ran SO MANY Crate and so called car motors in boats and to tell you the truth if all your parts are working well together in your application you should have no problems... Some also say various metal contents in some blocks offer less corrosion damage due to salt and lack of coolants (not found in lakes and rivers).
Hope this helps,
Denis
Well Said.
Interesting stuff. With all the talk about how marine engines being built different than car engines and most crate engines being advertised as not for marine use, these last two posts have me thinking twice. I was looking at the Merlin 509ci 540 hp crate that summit sells for $7500 and having it set up for marine use with looser clearances. Now im rethinking my ideas.
Taylorman,
Were are you Located?
If your near Sac Bob @ Spartan Engine Development & Machine Works knows his stuff and he does it right! However he can not be rushed, he is back logged quite a bit.
He is worth every dollar spent IMO.
Spartan Engine Development
604 Houston St West Sacramento, CA 95691-2216
916-371-7050
Hey Hallz, I'm in Sac. Never dealt with Bob. Does he have a dyno? Sometime this fall/winter I'll be buying a ZZ4 for the race boat and I want somebody to put it on a dyno to get my timing/jetting/cam break in etc squared away so there is less chance of me breaking something. Would he be a good guy to go to with this? I'm not a motor guy so I want to reduce the chance of me breaking anything as best I can-Aluminum Squirt
Hey Taylor Man,
If you will look at the peek torque & hp numbers on the gm crate motors they sure look good with an a or a/b impellor. Im thinking your boat would be a good 80mph boat on the motor with just a 502/502, maybe more.
Just some food for thought... Im putting together a NA 540. If you keep an eye out for good deals and buy good parts either new or used, you can get a lot more motor than your budget would have allowed had you paid for everything retail. The only thing I have bought used so far were a carb, manifold, and block, and I've saved about 1500 bucks and have some serious parts for my motor.
Good link and you can even read quite a bit of it!
http://www.amazon.com/gp/reader/1557...24#reader-page
I am the guy placecraft 20 wrote about, with the ZZ502.
All I can tell you as far as the difference in the 509 and the 502 is generally the block the GM 502 block is bored and finish honed to 4.447 and can only be overbored 1 time to 5.00 . The 509 blocks usually are a bowtie block and can be overbored several times and use the older style covers (timingchain, ect). I have put over 200 hours on my ZZ502, most of it has been run between 4500 and 5400 rpm. The 502 does come with a suggested redline of 5800 and I have never seen in my boat over 5600. I did follow the break in directions and put at least 20 hours on it before ever really holding it wide open. Good luck and enjoy.
Rollmaster timming chains, proform or harlan roller rockers, used manifolds, forged H beam rods, 10 under steel cranks, and a good set of used ported heads are all good ways to build a good HP motor on a budget!
As long as they are quality parts and preped correctly you can streach your $$ quite a way.
Here is an example I am picking up a new rebuilt 454 long block with TRW Forged 10:1 pistons, X-drilled steel crank, Stock rods w/ARP bolts, Clevite 77 bearings,melling hv/hp oil pump,Total seal rings, brass freeze plugs, all the tins and FelPro gaskets for $1500.
The heads are std ovalport that have been pocket ported and crane gold 1.8 roller rockers.
I am going to replace the rod with a set of H beams, bore it +30 and sell the std's to help pay for the new parts.
Once I swap over to the BBC I am going to add a set of AFR 2100-1 heads and go with a solid roller valvetrain.
I am hoping to be around the 6k mark and 600 hp, then the 150-200 shot of N20.
I am planning on a 2 year build out, anything may change buy then.
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