Best flame arrestor
 

What's the best flame arrestor out there? I don't care what it looks like I just wanna make power and hurt feelings. I've got a big prostock scoop so no clearance issues.

That's an Awesome statement!

No performance flame arrestor is going to give you any extra speed over another performance flame arrestor.

I'm sure that's true if your running stock stuff but put it on a naturally aspirated 1000hp motor and it might seem like someone forgot to pull in the anchor. I think I'm gonna end up making my own...

I beg to differ, Last boat I did FA performance data on lost almost 2mph with a K&N 9x3 assembly. Granted small light boat, but still a 350cid engine.

Edit in: Before someone states what they don't know, I do these easy tests the right way: ie same day and hour, same sdection of water, and handful of runs both ways. Also, again, a small light boat that responds to everything - including battery placement.

WWhat did you have on before the K&N arrestor?

the k&n marine arresters are very restrictave,i will not use them.

I've never used them but I kinda figured that much from pictures of them. Who's would you recommend on top of a dominator?

I've done fine with the bigger K&N's...on dyno too. But this boat could only fit that 9X3. FYI: Most boats I've seen with the KN FA have the 9x3's. Too bad.

teague sells some nice ones.

That's what it had. So I tested with and without. I was out tuning the boat that day. Carb, timing, props, etc. 2nd to last test was with muffler inserts with and without. Last, was the Arrestor.

Just Looked up my notes and they state: 1.6mph by removing it's K&N #59-3364. 68.1 mph without vs 65.5 with,. Edit: I believe notes where a typo and is supposed to be 66.5 with KN Arrestor.

I am no mathmetician, but I believe that is 2.6MPH

I would like to see some dyno sheets on this 1000hp NA engine with a dominator.

Oh snap. That's my computer notes taken from my written notes. Written notes are long gone of course.

It was a bunch of years (7 or 8?) ago but I would believe the 1.6mph as I remember just under 2mph for the FA and just about +2mph from removing the muffler inserts in the tailpipes. That boat gained good mph that day playing with it. The 68.1mph was correct as I have a pic of the GPS as part of my notes.

I have the k&n on the new 502 and the stock merc on the 454 should I use the stock one on my 502?

Well let me clarify. I doubt in real world conditions you are going to see any speed increases with Merc HP style flame arrestor, vs a Gil vs K&N, ect in a 26' Baja. Yes if you slap on a merc 330 arrestor you are going to choke the engine and lose speed. On the same hand, I kind of doubt if you spent to the money to build a 600 hp engine your going to slap that on your carb. When I was trying to squeeze every last MPH out of my 242 Formula, which had a very well built engine in it, I tried all sorts of arrestors and it didn't make any difference what was on top of the carb, but that is just my experience.

i think the k&n will be fine for stock power.

maybe it had a 400 hp shot of nitrous.

I understand you have scoop but without one for anyone, next time raise your engine hatch some if possible to see if you pick up some rpms & speed. On some boats the air flowing cork in the bottle is the how well the engine compartments are sealed up not allowing enough clean fresh air to enter along with holding heat.

Merc years ago had a SB about checking raised temps in the engine compartment and make sure not to exceed 176 degrees inwhich can promote vapor lock. Also as we all know higher air temps & engine compartment temps you lose hp numbers.. IMO it is better to reduce engine compartment temps and allow fresh air to enter and heated air to escape better, before worrying about which flame arrestor to use..

Me to waiting on a set of heads from CFE about 3 weeks out.

No but it might get a 50 shot to get there.

If you have 1000hp in a 24 Baja you are going to have your hands full, be careful.

I had 900 in the Baja. This is going in a 27' Donzi.

I called K&N when I was looking to upgrade my flame arrestor as the Hardin I was using a sharp edge at the air horn. Based on their info the 9x3 would be so restrictive for me that it would pull enough vacuum to close my power valves. I went with a velocity stack style housing with the largest 14" K&N element. AT 5600 rpm I am still showing 0 vacuum so no restrictions for me. Most of the flame arrestors I have seen either are way to small or have serious flow issues due to right angles at the air horn.

So, I'll take this a step further and ask if anyone has seen any serious gains by removing the choke butterfly and milling off the choke housing on a Holley 800. Not much need for the choke butterfly in most marine applications - most of the time all you have to do is bump the throttle a few times to squirt some fuel in there and then just keep the idle speed up until the engine warms up a little.

You were serious about a 1000 hp N/A engine? What size engine are you building to get that kind of power?

632 if I can get 1.6hp per cu. in its over 1000. Problem is I'm building it under the wifedar. So I can't really spend the money to squeeze everything out of it. It will make 950 no problem the last 50+ will cost another 3-4 grand. Either way it will be to much for the boat. In good water the boat has been mid 90's with 850 in perfect water.

You don't happen to have a picture do you?

Snake oil..

PM me and I will send you a photo.

Every modification is only as effective as it's necessity. Milling the air horn on an 800cfm carb on a 330 would be pretty ineffective, on a 572 it would be huge. Same thing with the flame arrestor, my 524 at 6000rpm needs lots of air.

OSO member "WETTE VETTE" did over 1000hp with a N/A 632 I believe.

is it a pump gas engine?

Yes. But not for the faint of heart. He put together himself but of course need a good pocket for what was done. Think he ran well over 120mph in his single engine cat.

Do a search...you'll find it. I believe 598cid or some where around there.

Wette Vette
 

Bbc_598 Craig Miscowicz
10.78:1 true pump gas 598.

Years ago I did a back to back run with and without my flame arrestor. I gained 0.00 mph by removing my flame arrestor. This was on a 500hp 502. But, my arrestor was the wire mesh kind which is the type I would recommend.

This is the one I had:
http://www.hardin-marine.com/p-14180...-arrestor.aspx

I really like mine.. pretty unrestricted.


http://33outlaw.zenfolio.com/img/s8/...23309656-4.jpg

That's what I'm talking about. Who makes that?

How much power did that thing make? And why the coated pistons?

[ATTACH=CONFIG]520490[/ATTACH]

These particular flame arrestors supported 1200 on the dyno. Installing them on, for the last pull, the engine lost like 4hp. Wasnt my engines in the pic that made that kinda power, but i wish!

On a max effort-ish N/A deal, you'll want to pay attention to the entry into the carb. Messing around on the dyno, I've seen a decent HP loss from those long flat flame arresters, even with the screens removed. There's even a considerable difference from just using different bases with no tops, with the flat ones being the worst. Air flow hates right angles.. If you imagine what the air looks like being forced into the carburetor, it's easy to visualize the difference between a nice tapered radius vs a flat plate and 90 deg edge.