I am 9.5:1 now.... That may change a little not sure yet..

That is almost dead identical to my blower cam from MK I previously ran that am going to reuse as a start ( may very well have to up compression or change cam specs before im done) to my 540 n/a project with except its on a 114, shows like 708 theoretical hp with a little less compression, prob too much cam for compression I have but am going to run it anyways, Smitty

My heads and intakes will be touched up, port marched and flowed before I even think about cams, that's per my buddy that's helping me get this fixed up, I am gonna ask him if bumping compression from 9.5 to 9.8 will hurt anything, I run 93 no matter what also so that's not a concern for me... But that's where I am starting, I am gonna look at everyone's ideas but minimalist who actually influences me, as of now it's my buddy Bill, scott and Joe...

Tim I run 9.5:1 with steel heads and 170-180* temps on 89 when I fill up on 93 it's a big difference in how the boat performs... Becomes a turd. I also mix 100:1 2 stroke oil every fill up. 9.5to 9.8 you will never know the difference. Never really start to see detonation issues until you get over 10.5:1

Be interesting to see how it performs Smitty

Has anyone ever verified flow of a 1050 carb 4150 style? Like for sure flow?

Dale can flow the carb for you.

That would be ideal cause 4150 1050's will vary. Very difficult to go by what you read as some have said the QF 1050's 933 up to 1,000 plus.

Tim, it would be nice if the guy doing your head+intake could flow your heads. Then flow heads with the intake then with intake & carb. You would probably learn something...

I may send it in, told wet best a 4150 will do is 940 CFm... At best ever.

Will try to, the person doing it is very thorough and I think my results will be much different this time, or at least right, really wish I went this route last time, buddy said if I can find a way to fit a spacer I should, worth a good 10 hp in every case he's seen... Gotta see if I can find space for it... New challenge lol

I don't know why you wouldn't.

You're gonna want to get on it. Dale is busy and your stuff gets worked on in the order it comes in no matter who you are.
I'd have him go through the both carbs and ensure ithey are what ithey are supposed to be. Just like the heads, it's not unheard of for parts to be assembled incorrectly or with the wrong parts.

no,those were the 1075 cams,i think

I had a couple ideas from looking at your bildge pics to gain some clearance... I would make a top pan for your arrestor but i would recess the top of the pan in the center so the top of the nut is even with the top of the pan. It would have a cup so to speak. Also trim some height out of the mesh in the arrestor. And lastly. If the bottom pan has a lip on it so it sits of the top of the carb make a flat bottom pan for it. With all that you could end up with an inch or two. We have a good machinist that custom makes us tops and bottoms on a Bridgeport. He actually has a table the he uses to but a nice raidused lip in the pans. Where there is a will there is a way...

Moving on with fixing, giving bill intake tomorrow, and keep moving on, get other engine out of boat adapter and take apart, still gotta mix all this with other things in life and now fall cleanup of yard that takes a lot of time... And car work... And my job ... Lol ugh too busy!!

A guy or two over at http://racingfuelsystems.myfunforum.org may know already. If not, by bore size, venturi size, base plate, and booster.

What you mean on top pan? Lost there lol

That being said about the mesh, I figure 3" is pushing it so I did t want to shorten it, wonder if anyone has flowed 3" vs 2" let's say... Hmm can't see it flowing enough but maybe? If I can go 2" I can add a 1" spacer

Such is life. Try building a boat from a bare hull with a 1 1/2 and a3 1/2 year old running around the shop.

On a side note.....we are all going to the track Friday night to blow off some steam and see if we can break our cars. You should blow the dust off the cobra and join us.
Give it some thought, be good to clear your head and burn some rubber!

I mean actual flow not calculations that's all

So I can blow up the Cobra?? Lol J/K I beat that car as hard as I can every time I drive it lol

I might have to work this move Friday night so not sure but maybe... If I don't work

I'm talking #;s they have from actual experience. Owner of forum is pretty smart and very experienced...same for a few others over there.

The top plate on the flame arrestor. The nut sits on top to bolt it down. The nut is 1/4". Recess the top plate so the nut isn't the highest point of the arrestor. Same the with the bottom. If it sits up off the carb just make a flat plate. That's gotta be over an 1" between the two. Then trim an inch out of the mesh. That's two inches more clearance. You can also increase the diameter of the top and bottom plates you have plenty of room around the sides...

It's a ford broham. They don't break like this boat stuff.

I wondered if lowering it and raising diameter would still flow enough hmmm

Gotcha

Just pull some mesh out. We only run with one layer of screen two tops. That's why you over insure you boat
:-)

You might go from 73.2, to 73.3! :poopoo:

I pretty much suggested a dominator from the get go on this build. That thread was a whole nother chit show of arguing. You said no way, because you couldn't fit it. Now, you're willing to find room, to fit a spacer under your current carb, and worried your carb is too small?! lol :angry-smiley-038:

I think this time around, you might be best to do your own engine development. What I mean is, taking advice from 30 different avenues, is not necessarily a bad thing, but at the end of the day, strapping the thing on a dyno, and trying out various carbs, various intakes, swapping exhaust, etc. Sometimes, what looks great on paper, doesn't always work.

You know Ryan Retter is flexible with you, and will work with you to try different things on the dyno, and won't nickel and dime you for the time. Theres no point in cutting up your hatch, if its a 10hp gain. Now, if you find a particular intake/carb combo, that nets you 25, 35, 40+hp , you may want to modify the hatch. Same thing with exhaust. You might find 10hp from switching from your manifolds to a header setup, or you might find 50hp. That might sway you to looking into different exhaust, or keeping what you have. But, you gotta do the testing. What works on one guys engine, might not work on yours. BCK spent some time on fine tuning his intake/carb combo. He found what , like 25hp doing so? Thats not a bad gain at all.

We have enough of us here, that I am sure someone would be willing to loan out an intake, a carb, maybe even some spacers, etc, to try .

Since I have your attention fora second don't forget the manilla folder, port thing. It will be good info for you and everyone.

Mark is a carb genius

Pulled mesh out last year haha only have 2 layers you see right through

I hear ya on the carb thing, learning more since 2014 also.. I am much smarter now and educated and continue to learn, you know I will do what I can to
Maximize this time, without re inventing wheel ...I trust my buddy's ability to come up with cam specs per cylinder head flow and will address all that when that time comes...hoping to Dyno in Jan or so... With you and Ryan, if that happens I am gonna schedule a 3-4 day trip to really play with things more, last time was a "let's see what you have session" as you know lets see how it goes this time!!!

p92 !

So assuming cam has no advance ground into based on the duration numbers you mentioned to install at 10 deg advanced. I see where larger CI engines absorbs duration say for instance from a 454 to a 540 or larger. So with that said would it also be correct to say comparing to 572 builds with different stroke combos the longer stroke build would have lower peak hp rpm than that of the shorter stroke. But back to your original comment I'd guess with the duration you mentioned based on a 540 you'd be looking at approximately 7k peak rpm + or -? If advancing 1 deg = 100 rpm to bring it in around 6k.

Interesting stuff.

Just a day or two ago I was aiming for 70 yet we all hung out in 69 forever.

Personally I feel if you need to advance a cam 10 degrees to get optimal performance then it's too big for the application. Why not just pick the right events when you order the cam, or find something closer off the shelf?

Very noticeable in your pics you posted of clearance concerns. Lol. Caught it right away.

A 540-565 with that a cam like that will Peter out right about 62-6300 rpm. Unless you have a restriction. We've ran this combination with 4150 carbs and they still make the numbers. With the ICL around 105 the motor will have a torque curve like a 4x4 from 3,000 rpm up and make a tick under 700ft lbs of torque. With the larger cubic inch stuff you can add some duration back the ICL up and split the lobes more because they naturally make more cylinder pressure. It's really hard to get RPM out of the Big Cubic inch stuff cause you really start running out of cylinder head intake and Carb. With a 632 and a conventional head you end up with a cam with high 280's 305 115-116 lsa and you'll be lucky if it will spin to 7,000 rpm. Buying heads 100% bare no seats no valve guides just a raw head helps. Cause then you can roll the valve angle a few degrees move the combustion chamber and angle mill the piss out of it. Work on getting the intake valve away from the cylinder wall by drilling the head bolt holes where they should be. These are the types of things involved with large motors and trying to make the big numbers. It's a lot more to it than buying a pair of CNC head and bolting them on the motor.

Black Baja, what ever happened to the Grumpy heads I sold you a few years ago?

How come we haven't seen each other on the water yet? Or maybe we have and I didn't out 2&2 together? Where do you usually run too?

We keept our Fountain in Middle river on a lift. We were out every weekend. Pretty much rafted up at Still Pond every Saturday and Sunday. Gave the heads to a friend of mine who never used them. I have two more sets of those same heads if you know anyone that needs heads.

What about breaking pushrod guides? I've snapped 3 since...