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Discussion Starter · #1 ·
i installed ods kit last week and got to put some miles on it. kit pulled great after initial bog at bottom. got it back to my garage and installed bmp fuel restrictor. i started with no jet at about 48 pounds of pressure. with 300 main it didnt drop pressure at all so i didnt even run it with that. went to 290 and it went down to 46.5. decided to take it out and run it and low and behold the bog was gone and it pulled much harder. i thought it waqs strange that the pressure didnt drop much but after inspecting plugs i saw that i was running right on the edge of too lean. i was also running the whole time with ethanol switch on just to be safe. with 290 jet and switch off it would have been to lean. either way the sled pulled way harder with the kit and reducer on it. i took it out and made some passes on tthe radar that night and it was very impressive. on ice it pulled 99 in aprox 660 ft. there were two other f7 that ran and they both pulled in the mid 80s. both were snopros though,one dd and one chain. 04 800 renegade clutched and mildly ported pulled 98 but it was set up gear wise for this distance. i was very impressed with the cat but am concened about adding the dd ypipe that i have ordered and doing the bmp pipe mod i have planned. i dont have too much room to add more fuel. and i dont want to get any leaner. will the ypipe and pipe mod need more fuel than current setup. relevant input would be appreciated


thanks ben
 

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I have found the same thing. I am prolly more conservative than most.

I decided that rather than install the fuel restrictor to match the airflow of the engine, I would increase the airflow of the engine to match the higher stock fuel pressure.

So, 2.5 deg. key and BMP pipe mod gave me the same performance as the restrictor (seat of the pants, I don't have radar) with much "nicer" looking plugs (Nice tanish brown coler, not fouled (rich), and not turning white (lean).
 

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this doesnt make sense to me. too lean with 290 main jet + ethanol switch on???? at 46psi???? something doesnt add up here. you can bring an f7 down to 40psi and be ok for 1500ft. a 290 main jet is conservative id think. also, installing a bmp pipe mod doesnt "match higher stock fuel pressure". what the heck are you talking about?
 

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Discussion Starter · #4 ·
i was thinking that maybe my guage was just off that much because i dont think i would want to take any more fuel away. the electrode was burnt white at the tip and then light brown half way up and by curve of electrode alittle darker. maybe i am reading plug wash incorrectly as i am not an experienced tuner but i think it was perfect. does anyone know if you have to shut sled off when you switch ethenol switch setting for it to change. i thought i should be able to get pressure down alot more but i would need more juets at the rate of decent per size i was seeing.
 

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<div class='quotetop'>QUOTE (bigblock2stroke @ Jan 8 2007, 06:28 PM) <{POST_SNAPBACK}></div>
I have found the same thing. I am prolly more conservative than most.

I decided that rather than install the fuel restrictor to match the airflow of the engine, I would increase the airflow of the engine to match the higher stock fuel pressure.

So, 2.5 deg. key and BMP pipe mod gave me the same performance as the restrictor (seat of the pants, I don't have radar) with much "nicer" looking plugs (Nice tanish brown coler, not fouled (rich), and not turning white (lean).[/b]
i got the same poster in my room as your avatar, signed by wyatt and reggie. got s second one signed by just wyatt if you want to buy it
 

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go out on the lake, run her for 800 feet or so WOT...hit kill switch, pull plugs, take several pictures, post them here...you'll know if you are too lean or not, you'll get a ton of responses.

and yes, it says right on my ethonal instuctions under the hood, to shut off the sled when switching off or on.


edit: guess the 06 x7 and the 03 f7 have different switches, so disregard my ethanol info.
 

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id like to see some pics of those plugs if you can get them????. sounds like she is running really nice. there are some threads floating around about the y-pipe leaning sleds down too much. this isnt the case on the f7's. i think this is an issue with the f1000.
 

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<div class='quotetop'>QUOTE (f7ben @ Jan 8 2007, 05:47 PM) <{POST_SNAPBACK}></div>
i installed ods kit last week and got to put some miles on it. kit pulled great after initial bog at bottom. got it back to my garage and installed bmp fuel restrictor. i started with no jet at about 48 pounds of pressure. with 300 main it didnt drop pressure at all so i didnt even run it with that. went to 290 and it went down to 46.5. decided to take it out and run it and low and behold the bog was gone and it pulled much harder. i thought it waqs strange that the pressure didnt drop much but after inspecting plugs i saw that i was running right on the edge of too lean. i was also running the whole time with ethanol switch on just to be safe. with 290 jet and switch off it would have been to lean. either way the sled pulled way harder with the kit and reducer on it. i took it out and made some passes on tthe radar that night and it was very impressive. on ice it pulled 99 in aprox 660 ft. there were two other f7 that ran and they both pulled in the mid 80s. both were snopros though,one dd and one chain. 04 800 renegade clutched and mildly ported pulled 98 but it was set up gear wise for this distance. i was very impressed with the cat but am concened about adding the dd ypipe that i have ordered and doing the bmp pipe mod i have planned. i dont have too much room to add more fuel. and i dont want to get any leaner. will the ypipe and pipe mod need more fuel than current setup. relevant input would be appreciated


thanks ben[/b]
Maybe a dumb question but you have me wondering, are you talking WOT pressure or idle pressure. you should see a pressure drop with 300 jet at WOT. and what year F7
 

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<div class='quotetop'>QUOTE (f7ben @ Jan 9 2007, 08:14 PM) <{POST_SNAPBACK}></div>
numbers i stated were at idle, pressure drops 2-3 pounds at wot[/b]
still not 100% sure we are talking about the same thing. but anyway most F7s will be around 44-46 lbs at idle you may see a slight drop WOT with no restriction. With say a 300 jet your idle pressure should be the same but now you should see a noticeable drop in WOT pressure maybe 41 lbs.
 

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Discussion Starter · #12 ·
so the idle pressure doesnt change regardless of what jets you run. i thought that it was supposed to change incrementally at idle and at wot. pressure didnt change much at all at idle and at wot with no jets it would go to 46.5 and not much change with 300 jet maybe 46 at wot and with 290 idle was at like 46.5 47 and at wot drops to like 44. this is much higher than i thought i would see so this is when i started checking plugs. heres a pic of one of the plugs after getting it in my garage. this is not a wot run. plug is richer than it was when i was checking before. let me know what you think of this plug condition. when i was running at wot and checking it was burnt white at tip of electrode and then alittle lighter than this pic all the way up the wash.
 

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HERE IS MY SET UP,03 F7,D&D LIGHT PIPE,D&D Y-PIPE,BMP HEAD MOD,4 D&D BULLSEYES,BMP COOLANT UPDATE,RUNNING BMP FUEL REDUCER WITH 300 MAIN JET,47-48 # AT IDLE,41-42 W.O.T.,PLUGS LOOK GOOD,I ALSO HAVE THE 06 ECU PROGRAM..
 

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<div class='quotetop'>QUOTE (f7ben @ Jan 8 2007, 10:14 PM) <{POST_SNAPBACK}></div>
will the pipe mod and y pipe lean it out more at any rpm,[/b]
When I bought the BMP pipe mod, they told me on the phone it (pipe mod) would richen up top end....thus they recommended a fuel restrictor.

However, I am keeping the restrictor at stock (no jet) until it is broken in, then I will take to a good dyno for final dial in. I think a dyno can give you the max "safe" HP, confirm your optimal RPM, check for any other issues with fuel/air, etc etc.....
 

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<div class='quotetop'>QUOTE (f7ben @ Jan 9 2007, 10:01 PM) <{POST_SNAPBACK}></div>
so the idle pressure doesnt change regardless of what jets you run. i thought that it was supposed to change incrementally at idle and at wot. pressure didnt change much at all at idle and at wot with no jets it would go to 46.5 and not much change with 300 jet maybe 46 at wot and with 290 idle was at like 46.5 47 and at wot drops to like 44. this is much higher than i thought i would see so this is when i started checking plugs. heres a pic of one of the plugs after getting it in my garage. this is not a wot run. plug is richer than it was when i was checking before. let me know what you think of this plug condition. when i was running at wot and checking it was burnt white at tip of electrode and then alittle lighter than this pic all the way up the wash.[/b]
No idle pressure does not change and don't be concerned with it (know what it is as a starting point). Until there is a big demand on fuel (WOT) you won't see a drop in pressure. the fuel restrictor is just like changing a main jet in a carb sled you are only affecting top end fuel. Be concerned what your WOT pressure is. You did not say what year you had (or year ecu programming) but 41 lbs for a 03-04 and a bit higher pressure for 05-06 is a good starting point but all are a bit different so check your plugs. The picture of the plug means nothing in reference to the fuel restriction at WOT you need to check your plugs after a WOT run. Stick with the 300 jet and 1000 ft runs until you get a handle on how lean you are.
 

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<div class='quotetop'>QUOTE (teamgreen03 @ Jan 8 2007, 10:05 PM) <{POST_SNAPBACK}></div>
this doesnt make sense to me. too lean with 290 main jet + ethanol switch on???? at 46psi???? something doesnt add up here. you can bring an f7 down to 40psi and be ok for 1500ft. a 290 main jet is conservative id think. also, installing a bmp pipe mod doesnt "match higher stock fuel pressure". what the heck are you talking about?[/b]
I don't know about the main jet, ethanol switches, and fuel pressures.

But the only way to get more hp at the crankshaft is either by changing airflow or fuel flow. In this case you have too much fuel and not enough air. If you add more air (pipe mod) you get more hp. What's not to understand?

You could also "restrict" the fuel to match the air, but that would be less efficient (and I suspect less hp than increasing the airflow to match the fuel flow).
 

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<div class='quotetop'>QUOTE (F7 Firecat @ Jan 8 2007, 11:14 PM) <{POST_SNAPBACK}></div>
<div class='quotetop'>QUOTE (bigblock2stroke @ Jan 8 2007, 06:28 PM) <{POST_SNAPBACK}>
I have found the same thing. I am prolly more conservative than most.

I decided that rather than install the fuel restrictor to match the airflow of the engine, I would increase the airflow of the engine to match the higher stock fuel pressure.

So, 2.5 deg. key and BMP pipe mod gave me the same performance as the restrictor (seat of the pants, I don't have radar) with much "nicer" looking plugs (Nice tanish brown coler, not fouled (rich), and not turning white (lean).[/b]
i got the same poster in my room as your avatar, signed by wyatt and reggie. got s second one signed by just wyatt if you want to buy it
[/b][/quote]

No thanks. Cool pic though.
 

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<div class='quotetop'>QUOTE (bigblock2stroke @ Jan 10 2007, 03:01 PM) <{POST_SNAPBACK}></div>
<div class='quotetop'>QUOTE (F7 Firecat @ Jan 8 2007, 11:14 PM) <{POST_SNAPBACK}>
<div class='quotetop'>QUOTE (bigblock2stroke @ Jan 8 2007, 06:28 PM) <{POST_SNAPBACK}>
I have found the same thing. I am prolly more conservative than most.

I decided that rather than install the fuel restrictor to match the airflow of the engine, I would increase the airflow of the engine to match the higher stock fuel pressure.

So, 2.5 deg. key and BMP pipe mod gave me the same performance as the restrictor (seat of the pants, I don't have radar) with much "nicer" looking plugs (Nice tanish brown coler, not fouled (rich), and not turning white (lean).[/b]
i got the same poster in my room as your avatar, signed by wyatt and reggie. got s second one signed by just wyatt if you want to buy it
[/b][/quote]

No thanks. Cool pic though.
[/b][/quote]

I saw Reggie at the New York boat show this past weekend,. That guy has some sweet hair!
 

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bigblock, i cant disagree with you about air and fuel combo = HP. im saying that sticking a BMP stealth pipe mod on an F7 isnt/doesnt/wont change your A/F ratio enough to create the kind of power that can be created from these motors. you have to lean them down to get the mixture right. again, i understand what you are saying but THAT pipe mod and a Y-pipe dont change the air/fuel ratio hardly at all. take a look at the dozen dyno reports that show it.
 
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