carb spacer

TRBenj - I was basically going off the original posts on this thread. I've learned a lot, mostly last minute, from this site...I was trying to be proactive. I'm getting closer to having my boat in the water and I didn't want something like this to bite me in the end. Thank you for pointing me in the direction of additional arrestors.

Yes, kapla, your explanation makes perfect sense. I will try that.

Thanks for the help-

A shorter carb spacer is fine. There are also shorter arrestors available: Marine Engine Parts (scroll down to part number 3745649).

I would be surprised if the Performer didnt fit under the 2001 box though, even with the stock arrestor and 1" spacer. Have you actually measured it?

Craig
what year is your boat? I recently did the engine rebuilt/upgrade on my 1992, and put the performer intake, stock spacer and stock flame arrestor, and it fit under the box fine. Maybe if you choose the performer rpm that its a tad taller you will need to cut the arrestor but someone else can verify.
Don´t forget to buy the adapter plate edl-2732 or summit sum-g1420 to put between the intake and the stock spacer as if not you will suck air as the carb spacer is bigger than the intake base...that will also make the setup a 1/4 inch or so taller....

I ported this 1 in.spacer in less than an hour.

You got it. Every bit helps, the biggest thing I see is preload most don't even what it means and does.

To answer your question yes it effects when the valves open and close. ex. advance open the valves sooner, retard they open later in relation to dead center.
As I said all Fords with a stock Ford timing chain gear are 8 degrees retard. To wake up that engine purchase a non ford timing timing, the retard was built into the crank gear.
Hydraulic lifters do play into opening, the biggest thing the is to do a perfect preload that lets the lifter work properly. If not you can lose power.

I just got a email from "bobchris" (aka79) of PN along with a explaination. He also suggested posting his explaination:

"Yes on paper the starting point is the same and is based off of the cam lobe profile, but the resulting effect of when the fuel/air mixture actually moves and enters the combustion chamber happens faster with a 1.7:1 ration thus sooner than a 1.6:1 rocker, what you can’t see in the graph is the fine detail of where the slope of the curves are because of the scale shown."

"The end effect being the fuel mixture enters the camber sooner with a 1.7:1 because it has traveled faster than a 1.6:1 rocker, then it travels greater distance generating more lift because of the increased lever arm and stays open longer because of the quicker closing of the valve due to the lever arm."

"So if you want to look a Point O then yes they are both the same only problem you have to look at the points after point 0 and the 1.7:1 will always be ahead of the 1.6:1 regardless of the distance traveled thus resulting in a larger sooner entering charge of fuel into the cylinder."

BTW, he still hasn't gotten any better with his spelling!!

8122pbrainard wrote: Off site, it's also been suggested to me that hydraulic lifters come into play with changing rocker ratio. Any comment?

What did you hear Pete?

SS 201 wrote: Tip Ask the cam grinder how the cam is ground. ex. some cam grinder use a advance or retard . ex. some are 2-4-degrees advance, some are 2-4 degrees retard. Now Ford uses a 8 degree retard built into the timing gear, suggest to buy a after market timing set to eliminate. When you know the cam specs you can either retard cam, or advance. Retard usually gives 100-200 rpm, advance loses 100-200 however gives more low in torque. Also can got the ratio change that's makes the cam change lift.

Bill,
Thanks for posting back on the subject.

I understand the concept that retarding or advancing the cam in relationship to the crank degrees changes the valve opening and closing degrees. Are you also saying it's really the profile of the cam and not the rocker ratio that governs the opening and closing degrees of the valves?

Off site, it's also been suggested to me that hydraulic lifters come into play with changing rocker ratio. Any comment?

LaurelLakeSkier wrote: SS 201 wrote: If you put 1.7 rockers on the intake valves you can gain some more power......This way it allows the valve to open sooner and more fuel to come in the cylinder. This may be a small detail but the 1.7 rockers shouldn't make any change in when the valves open, that would require a different cam. It will allow them to open up further however.

SS 201 wrote: It does, do the math, done every day. It was suggestion I guess this forum doesn't want to learn, Now I know why I quit posting, never changes.

Your suggestion on using the 1.7 rockers to give a performance boost was a good one. As I said, I was just trying to clear up a small detail in your explanation as to why they worked. I think most of us are on this forum to learn from others.....

Sometimes the way people describe things really doesn't get the point across. Pete's graph shows that the valves don't open any sooner BUT higher ratio rocker arms do in effect change the profile of the cam. You'll see that not only do the valves open to a higher lift but they open "faster" evidenced by the wider curve in the graph, I think this could easily be misinterpreted as opening sooner. Either way you want to call it the advice to install 1.7 rockers is good bang for the buck without having to go with a new cam.

Only question I have is why only on the intake valves?

LaurelLakeSkier wrote: SS 201 wrote: If you put 1.7 rockers on the intake valves you can gain some more power......This way it allows the valve to open sooner and more fuel to come in the cylinder. This may be a small detail but the 1.7 rockers shouldn't make any change in when the valves open, that would require a different cam. It will allow them to open up further however.

SS 201 wrote: It does, do the math, done every day. It was suggestion I guess this forum doesn't want to learn, Now I know why I quit posting, never changes.

I'd like to see the math on the concept. I'm totally open to learning whatever the result shows however am curious how the rocker ratio will change when the valves open. I would think a cam profile change would be needed as well.

BTW, this is a forum of open discussion with different views. I'm sure by now you have run into many different opinions but haven't learned to listen to different opinions. I'm sorry to hear that you will be no longer posting as I do know you have many years of engine experience behind you. Make sure you provide the math before you stop posting!!

EDIT:
Doing a preliminary search, I was able to find this. Looks like all the opening and closing points are the same with different ratio rockers.



Maybe more math is needed!!

SS 201 wrote: If you put 1.7 rockers on the intake valves you can gain some more power......This way it allows the valve to open sooner and more fuel to come in the cylinder.

This may be a small detail but the 1.7 rockers shouldn't make any change in when the valves open, that would require a different cam. It will allow them to open up further however.

Try Googling E basic power. I got one from them a while back.

didnt know that pete thanks ,i waz wondering if i could just cut down the one i have ?