How loud??
 

Plannign to go to a 350" 355hp ZZ4 crate motor, gona run headers, holley carb, thru hull.

Now the boat had through hub exhaust on the 4.3, how loud will through hull be on it with a 350? Strait through, not the silencer tips. (Corsa by the way)

What about mounting them right below the waterline so when the boat is not on plane, it is quiet, (for 90db checks) and when running i get that nice V8 sound. Will I have to worry about Reversion??

The zz4 is not designed to be a marine motor. It does not have the correct cam, bearing or piston clearance. I'm not sure, but it may not have forged pistons. This would not be my first choice for a marine engine. That said, I'd guess that it'll be quieter than the V-6. The 4.3's really rap. Yes, you can move the tips below the water line. Be sure to use a good flapper and have some extra rise to the system before turning down.

acctually the cam it comes with is a little mild for the heads it runs better with the hot cam and switch out the stamped rockers for allum. 1.6 rockers than it pulls 425hp @ 6000.
I agree with cord though not a boat motor, but you never know. may be a hot setup. you'd better ask someone who's tryed it. If you need one let me know I get them cheap.

I talked with the Factory 1 team Mutual Fun, he said he has been doing ZZ3 and ZZ4 swaps since 1991. The first boat got a ZZ3 and 125 shot of nitrous, not been taken apart ever and still runs fine.

Just Once, How Cheap?? :D

The only thing I would worry about with a ZZ4 engine would be the exhaust valves. Upgrading to inconel valves would be mandatory!

What about Manley valves??

Kids
 

Now how many extra newspapers are you going to have to deliver to be able to buy all this stuff ?

its not the news papers to be delievered thats first but getting the job first.

I'd like to hear some view points on that last question... Inconnel exhaust valves or manley SS exhaust valves? What's the diff?

BT :cool:

Job for you
 

Hyper, just come to my lake with me next summer and I'll pay you to wax the Spectre, top and bottom and clean the ole lady's pontoon, and I'll even let you drive the Spectre when your done, now is that a deal or what ?

What lake?

HB, just buy a 16 classic and pizz on that baja. You would look good in a classic:D

Inconel valves are not always necessary on naturally aspirated marine engines. I have been running high compression big and small blocks using Manley Severe Duty Stainless valves for years and have never had a problem. As a matter of fact the Stainless valves actually flow a little better than the inconel valves. Blower and Turbo motors are another story. Especially very high HP versions of these definately require inconel. Again, only my opinion.:cool:

If I got a nickel everytime someone said that, I would have a Scorpion 18...

Better yet, Are new valves even Necessary??

AND-- Exhaust valves?? I thought when the piston went down, it exposed the exhaust port? Guess 2 strokes are farther away than I though....

Manley "severe duty" valves are stainless.
Manley "extreme duty" valves are inconel.

2-strokes don't have any valves near the piston. Some have rotary or reed valves upstream near the carb, but nothing in the cylinder except ports for intake and exhaust.

4-strokes have intake and exhaust valves.

As far as exhaust below waterline, my old Correct Craft sounded cool like that...

HB- go here: 4 strokes

to learn about 4 strokes.

Hyper,
I'm sure that ZZ4 would work fine. However, make sure it has stainless or marine head gaskets if you're running raw water cooling! Also need to think about a marine distributor, alternator and starter. Automotive stuff won't do here.

Can you post up a link of where to find those parts?

Anyone know where to find cheap headers?

Thanks Wette Vette and Mcollistn.

BT :cool:

"Cheap" and the word "Marine" never go together. Add the word "header" and you have an impossible combination. The problem is that it will be impossible to match the header up to the existing tip location. They'll always be pointed at the wrong spot. So you're going to be looking for a new, low cost header. The cheapest one is by lightning. I think you'll be around $1,700 for a painted steel header. With their design you won't need a tail pipe so you'll be saving another $500 over other header designs. To lower the cost further you'll want to look for some aftermarket aluminum manifolds. The cast-iron ones are great for salt water and stock engine, but other than that they're a pretty crummy design. I think you can get a set for $1,200, but you'll need tail pipes. You can watch around for a used for alot less. The problem is that you're running small block and the rest of us are running big motors. Try to get ahold of a board member called "traviss". He did a small motor build-up this past year and can help you out.

Ive talked to Travis.

The only way to get headers in there and have thru hull would be to have the headers upside down, like how they are in a car. Is that really a bad thing??

Is upside down a bad thing? Ah....YEAH!! There are several reasons why this is bad. Water is one thing....it's gonna sit in the header....not good. Then theres the clearance issues....stringers and such are going to be in the way. I'd shop around for some used EMI's, Powerflow's, etc.... aluminum manifolds. They both make S pipes so you can run down to the Y pipe on silent choice systems. I'm pretty sure you can simply go thru the hull from here.....be about right for what you want.

Thats what I thought.

I know that with the stock manifolds and risers on the V6 in it now, I would need 2 rubber hoses, tips and clamps and thats it. Im assuming it is the same on the V8.

Only if you're going to go straight out the transom. You CANNOT put any bends in the rubber hose......it WILL burn even with a slight bend in it.

How would Ido the exhaust then? It has to curve to go from the riser to DOWN towards the tips and then BACK to connect to the tips.

Upsidedown? Lightnings are no higher than the carb. Check out www.boatheaders.com

Lightning makes a small block header and I'll guarantee you they don't mount upsidedown. You can get them for quite a bit less than list price.


P.S. - check out their used stuff. looks like a customer hacked up some small block headers, might be the ticket for your application.

BUT the dilema is, the headers would need to be upside down to even be near the tips. theres a swim deck on the back that they would need to go under. not saying i would mount them upside down, but that is how they would be even close to the tips.

The headers need to go over the top. There will be a S shaped pipe that will connect the header to the tip.

Would that be custom made up??
Anyone from Ohio region weld?

Hyper........
You are not going to want to here this,but.........

You have NO idea the problems you are going to see with this project !!!!!

Then....If & when you get it to work..You will have 0 resale on that boat !!!

Why not do some mild mods to that v6 ? Vortec heads, Cam ?

Save the big bucks for something built for a V8.......

Not trying to bust youre bubble guy....Just...Been there..Done that

Where can I get mods for the V6?? If I go that route, It needs to be a new engine, this one has somewhere around 1300-1400 hours on it!!!

Should be able to find a Vortec in a junk yard....Lotsa of them out there......
Tear it down and start from there.......Rods,Pistons,valves =
Small block chev parts......Buy Dennis Moores book for good
advice......

You will still have to do some research.......Just easier than a
swap !!!

Lots of power to be found in those vortechs !!!
You don't need a ton of torque in that light boat...Them V6s
love to rev !!!!

I know that the 4.3 at 190hp will run next to a 260hp V8 due to all the added weight.

Whatever you plan on spending, multiply it by two.

As for inconnel valves..........I do not think they make them for Small blocks

If you want a good valve, I would recommend Manley Severe Duty. However, I have also used competition products severe Duty valves. They are about 1/2 the price, and I had almost 400 hours on them, and I'm running a lot more cam & spring than you'll be. At my rebuild, I just touuched them up and put them back in. I'm running around a .600 in lift, solid roller. My springs are 200-210 on the seat & over 500 lb open.

Do a little homework while it's still cold out :-)

I don't have inconel valves in my 540's either---just a very good one piece stainless valve for my exhaust. I was told that I would NOT need the inconel valves. I think they are Ferrea brand valves. I run a DRY header/exhaust system---no problems.

Hyper you can use PVC to make the hoses that are bent. The black stuff is better to use if you can find it.

Jon

Forget trying to make a Baja faster. It will still be a Baja. Im gona make some money over the winter and try to buy a Donzi 16 or 18 Classic.

Man, you are starting to talk about some serious cashola Hyper. You may want to take a hard look at getting a differ boat that will be more economical. Remember, resale is something you need to consider if you are going to start fabricating. Either way, have fun. Just remember, if you think you are going to spend 5K, better plan on atleast 6, if not alot more. You just nickle and dime yourself to death when you start getting into these projects. That is why I think you may want to go with a boat that has a little better track record with anything 350hp or so. Hate to see you sink all this dough and have a boat that won't let you run the power you have spent so much $$ to put in it. Odds are it would work out fine, but you never know. Food for thought. Later

Whhoopps, looks like you guys beat me too the punch, sorry to repeat all the ab ove advice....:D