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FJ Land speed racer

Started by fj1289, July 20, 2015, 07:24:30 PM

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fj1289

Quote from: FJmonkey on September 11, 2017, 05:36:49 PM
Wow, you are gonna need a big tube of JB weld to fix that.
Are you good with jigsaw puzzles?!

This is what I've pulled out so far



I'll be pulling the engine to go through it - get all the pieces out of the pan, clean oil pump screen, replace bearings, clean oil passages, etc. 

Then this will go in for next time

Flynt

Quote from: fj1289 on September 11, 2017, 06:44:45 PM

This is what I've pulled out so far




Now that's how you get 'er done!

Frank
There's plenty of time for sleep in the grave...

fj1289

We are using as many stock parts in these engines as possible - it is amazing to me this is the first stock part we've had fail.   Last year we did use a billet basket.  I chose to use a stock basket this year.  I've learned through Randy and Robert just how much the race cars stress the driveline -- to the point of stripping gears in the transmission!  I have NEVER heard of a bike - no matter what the use - doing that! 

When I first started planning the drag bike build I had several people warn me about the "weak" cranks and the tendency to break at high rpms and high horsepower levels.  But no one could give me any real details.  We've had no crank issues.   I attribute the failures in drag racing to be related to high rpm clutch drop style launches on large slicks with wheelie bars.  I also assumed that style use was where the clutch saw the most stress.   Since we don't do that style launch at the Colorado Mile I figured the stock basket was good to go.  I figured wrong, and now we know the limits of that part in this application!

I'm really impressed with the strength and durability of the Yamaha parts.  A guy there with a very nice 94 GSXR7/11 had already "folded" a set of GSXR rods with a smaller shot of nitrous than we made most of our runs with.  Admittedly we used XJR rods - but still stock Yamaha parts for this application!

jnimbostratus

Really exciting stuff you got going on. I wish I had some kind of standing mile thing by me. I would totally build another turbo bike, or just maybe redo mine with some fairings. Sucks about the clutch tho, I would expect that from a hard launch drag setup not a soft start high end pull. Crazy good luck getting it back together brother. I know you'll do her up right.

fj1289

The lead up to this year's Colorado Mile was not how I had planned ...

I finally completed the wiring, brakes, etc 10 days before the race.  Time enough to do a little tuning, do a test session or two at Bandimere, then on to the race!  Except when I go to crank the engine, it won't start.   It keeps blowing the fuse for the coils.  Check the coil wiring - move the grounds around with no improvement.   Eventually open up the ECU and find some burned wires among the ignition mods and input/outputs I added.  Crap!  Don't have the cash free to replace the ECU.  Think it over for a day and realize I can cut the aftermarket connector board off the motherboard and solder in a standard connector.  I don't want to use the standard megasquirt connector - but there is no choice now.   I'll also add the MS3X expansion card and take advantage of the ready to use inputs and outputs.  Again, this means adding another crazy huge "1980's printer connector" used by the standard megasquirt ECUs.  And it means rewiring everything to the new connectors. 

I finally get the bike cranked 5 days before the race.  Then set about installing the new nitrous system and wiring the additional systems.  The bike was ready to be ridden and start tuning 2 days before the race.   I go for a short ride to get enough data to ensure the bike will run well enough to take to Test-N-Tune at Bandimere.   Well, the manual cam chain adjuster (I intended to replace with the stock Yamaha automatic tensioner) backed out during the test ride and the engine quit. So, Thursday morning comes and instead of loading the trailer to go to the race, I'm pulling the head to replace 4 bent valves!  Bent the intakes on #1 and exhausts on #4.  So I sort through some of the valves I've removed from heads in the past and do a quick "valve job" with some valve grinding compound and get the head back together.  We get the engine cranked again at 2:30 in the morning on Friday - the day of the race!

fj1289

Got a couple videos trimmed and posted to the YouTube channel. 

Here's a link to a run early on Sunday.  We turned the rear mount camera around to see the rear suspension action and see if we had enough room to raise the nitrous bottle in the mount - with the intent to get the bottle valve a little more out of the wind under the bike.  https://m.youtube.com/watch?v=y-JElg_o9a0

fj1289

This is a short clip from the final run.   The clutch basket let's go at the 4-5 shift just before the 1/2 mile point just over 162 mph.   Tune was still over rich as seen by the black smoke while the nitrous is spraying.  

(For some reason can't download the entire clip - can only pull off 30 sec segments - only clip with this issue)

https://m.youtube.com/watch?v=QRhL4egcSRk

As you can see in the clip - it was really a non-event.   It was pulling hard, shift, then nothing - engine just free revs.  Still need to look over the datalog and see if it hit the rev limiter. 

fj1289

Well, a week later and I figured out what caused the tuning issue was last Sunday. 

The megasquirt ECU operates off a VE table to calculate fuel.   It makes changing something like injectors easy -- enter the new injector info in the injector section and all the fuel calculations are automatically adjusted.  There may be some minor idle adjustments need to be made, especially with a swap to large injectors.  BUT, the added fuel for nitrous is entered in raw pulse width in milliseconds.  I forgot about this when adjusting the tune for the new injectors.  I used the existing added fuel settings with the larger injectors.   Add 50% larger injectors on a tune that is already 10% rich, and you end up with 165% of the fuel needed - enough to push the AFR to richer than 8:1! 

A normally aspirated engine will simply quit running at AFRs above that even.  Add nitrous to the mix and it will still run at richer mixtures.  I had no idea it would even run at that rich of a mixture!  No wonder it was missing at high rpms!  I first bit off on an ignition issue.  Then made the correct fuel adjustment in the wrong part of the menu. Lost a lot of time to this issue.  In the end, probably didn't make a difference to our end results (we would've just blown the clutch basket sooner!) -- but was a good learning experience with nitrous tuning.   

fj1289

Cleaned out the oil pump pick up screen this evening.



Amazing how much crap it accumulates.  But it did its job - the oil pump still looks good!  I was a bit disturbed to find this though   



Crazy thing is both the oil pump drive gears look good and have all their teeth!



So it's either from something else I'm not aware of; or it is from some previous damage before I bought it...

Firehawk068

Lots of info to think over...............tuning can be confusing for sure!

Could that missing tooth be something from the transmission? Or are the gears typically bigger than that?

Are you planning on splitting the engine and doing a complete tear-down?

Perhaps for 2018, I can help you start testing in April.................... :sarcastic:
Alan H.
Denver, CO
'90 FJ1200

fj1289

We're thinking that tooth may have been from a starter drive gear I broke a couple years ago - strong battery plus some bad ignition settings in the start menu for the EFI controller I was using lead to a bad kickback while trying to start the engine.   

I don't think there is anything that small related to the transmission - all the accessory drives come off the crank or clutch as far as I know. 

April?!  I'm trying to get this one back out later this month and/or early October!  Want to work on the rear wheel speed sensor, auto shifting, launch limiter (2-step), and progressing the nitrous via speed vice time...as well as getting the nitrous tune right!  I'll let you know when it's going to a test and tune.  Thanks again for all the help!

Firehawk068

Let me know. I'll try to get out and give you a hand.
Alan H.
Denver, CO
'90 FJ1200

racerrad8

Quote from: fj1289 on September 17, 2017, 10:37:33 PM
...Add 50% larger injectors on a tune that is already 10% rich, and you end up with 165% of the fuel needed - enough to push the AFR to richer than 8:1! 

I thought maybe you were trying to convert over to diesel... :shout:

That thing is "Rolling the Coal..."
https://youtu.be/2E2GFfpAWss?t=1m57s

Randy - RPM

Randy - RPM

fj1289

Quote from: racerrad8 on September 20, 2017, 06:03:14 PM
Quote from: fj1289 on September 17, 2017, 10:37:33 PM
...Add 50% larger injectors on a tune that is already 10% rich, and you end up with 165% of the fuel needed - enough to push the AFR to richer than 8:1! 

I thought maybe you were trying to convert over to diesel... :shout:

That thing is "Rolling the Coal..."
https://youtu.be/2E2GFfpAWss?t=1m57s

Randy - RPM



No doubt!  Really, I was going for the flame thrower effect -- next year we'll add spark plugs to the exhaust tip!

I still can't believe it would even run that rich.  (Goes to show how much nitrous "enhances" combustion burn)  When we first started trying to figure out the miss we were having, Alan suggested we shoot the temps of the headers at the end of the run.  We were so rich that #1 had actually started running cooler than the others by about 100 degrees.   As we pulled fuel out it would rev a little higher in 4th and 5th and the temp on #1 would increase a bit.  If we had another 2 hours (3 - 4 runs) we would have gotten the tune pretty spot on even though I hadn't figured out WHY we were so rich. 

JMR

If you break the HD basket I can sell you a mint, extremely low mileage HD unit.