I agree with what madmax said.

If you plan on keeping the boat a long time, then mod away. But if you plan on selling in a few years and stepping up, then keep the mods light.

Dave
I hope you don't let them scare you away from modifying your Hammer. I am tickled to death with mine and it out performs most others costing significantly more. It is true that when the water gets rough I need to be more conservative. I did put add on Imco hydraulic steering which helped the handling. I am still running a 3 blade Mirage, which I understand does not help handling. In calm water I can get a chine walk but have been able to drive through it and I am currently running a little over 77 on GPS. There are a lot of other boats faster, but this speed sure gives you a rush in this size boat. I am considering going to a shorter drive which should increase speed further and may help handling. I don't think you get much return on the cost of your modifications on any boat. But what the heck, modifying it is half the fun. There was a guy on this board by the name of Brad Perry that was running a little over 100 in a Hammer. Do what makes you feel good. Life is to short to do much of anything else.

Very True Sledge.......half the fun is modifying it.!

Here's what i did to my 310 to wake it up. And my advice was only that.....advice. If you like the hammer, by all means, have at it. It's a rocketship acceleration-wise, even with the base motor.!


97 310hp carbed:

Edelbrock performer rpm intake $200
L-29 Vortec heads, complete, used $500
Gil manifolds and risers $1200
Holley 750cfm carb, used $150
GM 454HO cam, new $125
Springs, retainers, etc off 502, new $75
Valve spring rotator eliminators, new $35
K&N 14X3 marine filter, new $80
454 Mag Thunderbolt V chip, used $125
3/8" pushrods, new $70
Labbed 25 mirage prop, used, $400
Misc gaskets and stuff to hook it all up, $200

Jetted carb at 82's all around, timing at 30 degrees total. Engine pings on 87 octane, Ok on 89.


Boat went from 62mph to 69-70mph gps.

So........

With the prop, $3160, without $2760.

Would i do it again?.....nope:(

Try this version:

Buy a used carbed Hp500 (7K if your lucky)
Sell your motor ($2500-3K)

now you are only out $4000 to $4500 bucks. You would have spent 3 grand for the mods I listed. $4K-3K = $1000 bucks.

So basically for a thousand bucks, you can have a motor that will run CIRCLES around the 454, and you'll have added REAL value to your boat at resale time.....

Again, only advice......:p

yeah man you ought to check out Brad Perry's Hammer....I don't think I've seen a cleaner, more modded out Hammer ever.

Since you did say you were new to marine engines, realize that it will take 15-20 hp to gain 1 mph and every 1 mph will cost you between $500 and $1000 for the mods.
Best bang for the $$$ is to lab the prop and enjoy the boat for what is designed for.
Also, adding 100hp to your boat could significantly increase your insurance premium or void the policy if you don't tell them and make a claim.

Cold..whats that... It was an honest 65 yesterday.:p To bad its all down hill from here.:D

Great advice from everyone.

Brian

70mph is a must so I want to do minor mods to make the boat run that comfortably. I have not had it in the water yet so I am curios to see what it will do in stock form. I also have questions about general matainence. I want to go through all the fluids before I test it out. What should I do, oil?, gear lube for the bravo drive?, fuel filter?Give me a laundry list here guys.

Hey David,

I also believe that making changes along the way is half the fun.:D

I thought a 1997 would have already had the L-29 heads, but I guess only the MPI version... Madmax would know.
If you would like a set of L-29 heads, I will have a set available with about 100hours on them soon.
$300 is what I payed for the set that are at the machine shop now. So that's what I would ask for the set that will come off my engine...
Not sure what you would consider minor mods???
Madmax's list is quite long. I know he would probably go with the ZZ502 cam not the HO cam on another go around.
I have not seen any HP500 for 7K, but there are 454Mag MPI around for 5-6 and 502mag MPI for 6-7.

Your list sounds good to me... Oil, Gear Lube, Fuel filter, and maybe add a new set of plugs.

Good Luck with your new ride!

Thanks for all the great responses. This is a new thing for me so I guess I will learn as I go along. Most likley I will end up going with a 454 or 502mag hammer in the future. I am limited to a 20ft boat because I live on a small lake. I will be the only guy with a baja, eveyone else has ski natiques. Dave H

hello i have the 310hp slow pig can you help me with a few mods?
i just bought gil manifolds and tubes and 4 inch tips .
currently i have a 23 pitch prop and a 25 pitch prop 3 blade ss
im looking into a set of heads and trying to decide weather or not to ditch the mpi and carb it
thanks