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A more power

Started by acman, October 19, 2010, 08:31:07 PM

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acman


Pat Conlon

Interesting.....( note to self: I've wondered what to do with all that extra room, now that I have my new Uni-Pods...)

Tell us about this set up.
I don't know much about giggle gas but it looks to be a 2 stage dry system  (I think)

If it's a dry system, what do you do to keep the motor from running lean when the gas is flowing?

Thanks for the photo.

Pat
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Dan Filetti

Any idea what sort of power it makes?  

Although I'm not sure I'd put stock in overall mechanical longevity, that may well make Brutus type numbers or more -fifteen seconds at a time that is.

Fits right in there doesn't it.

Nice work.

Dan

Live hardy, or go home. 

andyb

That's a wet kit.  Would like to hear more about it also, I was considering doing something very similar, but concerned that the bottle would break a syphon tube from vibration and feed gas instead of liquid.

Depending on what's been done to the motor, that could make quite a lot more than any of the naturally aspirated machines here.  The lower the the tach reads when the button's pushed, the more torque is made, and shocking amounts of it. 

acman

It is a wet system.already on the bike when i bought it, according to the jet size it is a 75 shot, well out of sight ,when fairings are on .this is the one i bought for 800.dollars ,it sathttp://fjowners.com/gallery/860_17_10_10_4_45_56.jpeg for 8 years now trying to get it ready for the road.winter project

Perez

It took me a minute to realize what I was looking at.....spray!

Don't some of the newere systems now have a way of monitoring temperature so you can't cook the engine?......they are supposed to be better then some of the earlier systems.

andyb

Is that a 1lb or a 2lb bottle?  At a 75 shot, you'd be frosting the bottle so quickly that it'd really only be good for one strong blast, if it's a 1lb'er.

No real way to monitor head temp on the FJ, short of fairly extensive mods.  You could always use EGT probes and some window switches, but seems easier to just watch the bottle pressure and have it tuned decently.

Perez

That was the other thing I was thinking of.....that seems like a really big bottle for a bike. Do they make smaller?

The size of the tank is one thing, but a properly designed control system is another item that alot of N02 systems seem to be missing and hence the bad reputation. A NO2 system SHOULD be something you press maybe once a week maybe once a month. A 10 shot system should last you all summer. Otherwize, you bought a bike that is too small.

I remember watching something on one of those Hot Rod TV shows and they were showing what a properly designed spray system should be. I believe they were watching for a rise in exhaust gas temperature (an additional sensor) and as it rose, the delivery pressure to the NO2 was reduced. The regulator to the NO2 bottle adjusted itself according to the signal from the exh temp sensor.

That made alot of sense to me. In the heat of the moment you could find yourself going for that 3rd or 4th shot of spray that will toast the engine. A syst like this would hopefully eliminate that.

andyb

Standard bottle sizes are 10oz, 1lb, 2lb, 2.5lb.  They go by amount they hold, not by their own weight.  A 2lb is the same as a 2.5, but slightly shorter. 

Really, there isn't much use for it except at a dragstrip or for show.  Not uncommon to use several pounds in a day at the track, it's also a good way to set up your airshifter (a CO2 regulator is required, though).  You can go through a staggering amount of the stuff if you've got a large shot, though.  A quick rule of thumb is one pound at 10hp will last one minute, but you never want to spray more than half of the bottle's capacity at a shot (or the bottle will frost over and the pressure goes away as it cools).

Still working on my motor, making things as absolutely bulletproof as possible short of big rods, and then we'll see just how much spray it takes to twist a stock swingarm :)


WestOzFJ

Quote from: andyb on October 20, 2010, 10:07:22 AM
No real way to monitor head temp on the FJ, short of fairly extensive mods.

Go-Karters and model car engine tuners use contact thermo couplers with sometimes tiny digital guages (on 1/8 model cars!) with all kind of functionality such peak held values, some with nema data logging capability and switchable outputs...

I'm currently looking to attach one of these contact probes near the spark plug on one of the centre cylinders as an ECU input - rather than EGT.

IMHO and experience, utilizing combustion chamber temperature is more useful than exhaust temp and the only way I can really summarily explain why after many engine tuning projects I've come to think this is to say: EGT measures what's happening after the "event" but to measure at or close to the combustion chamber is to "know what's going on where the action really is at".

For example, retard the ignition timing in the upper rpm under power (which could be a good thing to do with NO2) raises EGT but lowers CC temp.  Another: do one run, after which exhaust temps drop/recover quickly but overall head temp can stay elevated for some time but by EGT measurement is "ready" for another run when reality is probably needs a bit more of a cool down...

Just my humble opinion but I think air cooled heads give a unique opportunity (compared to liquid cooled) to monitor combustion chamber temperatures and utilise that info because you don't have the water jacket in the way to get close to CC....

Not saying EGT is wrong, just think something a little closer to CCT is more representative, responsive and worth the effort.

Anyway, all food for thought.

Happy tuning...

Victor.

Firehawk068

Back when I lived in NY, my Brother and I used to dabble in vintage air-cooled snowmobiles (my Brother still does)
Some of them (Arctic Cat) came with Cylinder head temp guages..... They used a temp guage with 2 separate needles for the left and right scales. The temp probe wires were attached to little rings that you install the spark plug through, and tightened it onto the cylinder head.  They worked fairly well, and I imagine you could use something like that on an FJ engine..........just don't know where you'd mount the guages though.....
Sometimes the temp guage kits come up on Ebay, and my Brother sometimes scoops them up if the price is right.
Alan H.
Denver, CO
'90 FJ1200

andyb

Interesting stuff!  Never have seen that at the track, on sleds nor otherwise with nitrous.  Any concern for strength in a boosted application?  The other question is how fast to react are they to changes?  I mean, you could come up with window switches somehow to turn things off after a certain temp, but the big blue squirt gun can do a lot of damage in a very, very short time if there's a problem with fuel delivery.

An interesting way of ensuring safety came from a gent I met at the track.  Was helping him fix a throttle linkage, and picking his brain on his nitrous install (CBR1100XX, +10" arm, motor had good pistons and headwork, spraying 100hp with a progressive controller... quite quick!).  He said one of the classic cheap tricks to use is to not use the typical cold plugs;  rather than the piston melting, the ground strap burns away and that cylinder drops.  Plugs are cheap to replace and it's an easy repair in the pits.

I'm still pondering various solutions myself, pretty sure I know how I'm going to have things set up, but still searching for room for everything!  After seeing the original picture, I'm wondering if relocating the battery would give me enough room to do things the way I'd like.  Things to ponder while the motor slowly comes together (again!).

acman


andyb

Straight into the rubber!  Can you take a picture looking down the intake tract?  I wonder how they're being retained, a nut internally, silicone, etc?

acman