LegendsRacer - Legends & Bandolero Racing Forum
LEGENDS => Engine Care & Tuning => Topic started by: RickyBobby on November 05, 2007, 03:56:23 pm
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I run a black box ignition system that came with my car. Everywhere I look there are different combinations of red box and black box, however every report I see on the 1200 motor is that is starts loosing power after 9500 rpm. My question is if you are at a fine line of needing more straighline bandwidth would you go up a gear or put in a red box?
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http://www.legendsracer.com/index.php/topic,118.0.html
Hey RB, that link takes you to a thread where I got a little education on the different boxes. Maybe that will help you decide.
Generally, I play with gear and setup until I get the fastest lap time. If you notice that the cars at your track with more top end speed can't make the pass before the next entry, then acceleration will probably be more important.
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There are two black box systems and one red box.
1)Old style black box with vacuum module mounted next to it, max 10,300(aprox).
2)Newer style black box 9900 ropm(approx)
3)Red box system 10,300-10,500 (approx)
The 9900 system is a rookie system, there are situations you need the extra 300-500 rpm to bury the car in the corner, yes the band peaks at about 8500-9000 rpm, but you have to carry the momentum further, and if you gear the car to run out of gear 9300 rpm at the end of the straight you will lose too much bottom end (off the corner), generally off the corner is where you gain momentum to pass. You really need to use all you can get, especially on short tracks.
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The black box I have is an older original system and the reve limiter is at 9500 RPM. I get a great jump on the field coming out of the turns but I hit the limiter before I dive into the corner. Some of the guys have said to go to a bigger gear as I will get more rolling speed in the corner as well but my Father in Law who build drag cars for many years said keep the same gear as I do get that great jump on the field but I need more RPM's for starightline speed.
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Is the vacuum box a vacuum ignition advance, or a feature that is not use but just identifies the box?
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The vac advance is used on the Legends car, the boxes with vac advance will have a vac module next to the box, under it or near it. The vac line goes to the intake area behind one of the carbs. This system is a very good system, the problem is it is an old system and parts are very hard to find, so the alternative is the red box system.
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Is the FJ box available from a Yamaha dealership, or is a legends specific part?
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knoxracing....you say that is I gear the car to hit the rev limiter at the end of the straight I will not have anything coming out of the corner. Can you expand on this? My thinking was I would be at a higher RPM than the guys running a taller gear when I exit the corner. I think it is around 6000 where the other guys would be even lower. Wouldn't I have more pull out of the turn then?
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or anyone else who may have some insight..........
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Now we gear the car to just tap the limiter just before lifting for the turn. If we drop the revs back we will say a grand you would still have the same pull off but you would be hitting the limited 1/2 way down the straight, or if you change the gear so you dont hit the limiter until the end of the striaght the gear would drop the rev coming off so much other guys would just pull away
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again I am confused. you say you set up the car to hit the limiter jsut before hitting the turn but you also say that if you set it up to hit it at the end of the straight (which is the start of the trun) you will be too low in the revs. With the black box right now I hit the limiter for a little bit down the front stretch and just hit it as I start the turn on the back stretch. I am running a 3.73 gear and the other guys are running 3.58. I get more pull currently coming off the turn to start the straight away than the rest of the field. I can usually gain 2 spots just on the green flag drop. So my thinking is with the red box I willl maintina that pull and gain more top end RPM's that I won't run out as I go down the straight away. However with a shorter gear it pulls you back more in the corner so am I loosing rolling speed in the corners.
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If your car pulls good with the gear you have and just need a some more RPMs at the top then good. I dont know what kind of tracks you race at, here in ohio we run and 2 tracks with tight turns and one that is like 2 drag strips and a hairpin. at that track if you have a gear to get off the turn without shifting you MAY run out of revs at the top. With the red box you have extra rpms.
Now there is a movment afoot to maybe someday limiting the rpms back down with a maybe a inline limiter of some kind. I just talked to our local dealer who stated that 600 sent some motors out to some cup teams to test and see why cranks were braking. The report came back and stated that we, 600, should pull the rpms back to make the motor last longer.
If 600 can do this and sell the limiter and maybe more gears to racers that have to change to get the rpms in the sweet spot 600 will make a change some day..
Dave
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RB,
Are you running the same gears as everyone else at the track? Just curious was wondering if you are maybe running the wrong gear, another advantage to the Red Box setup is you can change out spark plug wires, on the older systems you could not.....anyway double check to see what gear other are running it may surprise you.
Mike.
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Does anyone shift on ovals? If the transmission would take it, I would think that it would help on tracks with long straight aways. Never was an option for me before, but with the inline shifters it should be pretty easy to go up a gear.
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I raced with a guy that did not have time to change the gear and he had to shift. It worked he was still fast. I dont know how much the trans could take, but it does work
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most of the guys at our track are running a 3.58 gear. Some still run a 3.73. We run in 4th gear and the track has longer straighaways with tight turns. This is why I think I get a better drive off the turn than the other guys as their RPM's have dropped off too much. My blackbox does not have a vaccum advance so I am hitting the limiter around 9600. With the red box of 10500 I would have more RPM range. I guess what I am asking is am I loosing rolling speed in the corner with the shorter gear or and I doing it right by getting on the gas quicker. When we have our test and tune day I will be able to see what my lap times are with the red box installed as it just arrived.
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Hey RB,
So you're going for the red box eh?! Good for you. I'm running the 3.73 gear, in fifth gear. I've got the black box ignition. Not sure if with the vacuum or not. I'll check. Be interesting to see how mine runs compared to yours.
Mike
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In 5th? I think that is what Paul is running too but I just don't know how he gets the drive off coming out of the corner in 5th. I thought he was in 4th.
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I'm not sure what gear Todd is using, and what gear he is in, but I had no problems keeping up to him around and out of the corners.
Too funny, I'm behind cleaning up the body damage on my car because even though I don't own a snow blower, I've had 4 of them in my garage over the last two weeks. Friends and relatives realize I've got a nice warm, well equipped garage, and all of a sudden they need that blower working...
It's a good thing that Sandi's '48 Mercury pickup is outside the garage now and blocking half the garage door, or I'd have a lineup looking to do work on their cars too!
Mike
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Well I learnt at the end of the year that you just stay behind Todd until he spins out and then you are good :-). I think he is running a 3.58 as well. Tim, and Frank are running 3.58 with red box. I am just not convinced that a 3.58 is going to be that much better. Cap City has tight turns so getting good acceleration off the turns seems to have me running right with Todd as well so I think if I get more straight away speed with the red box ignition I should be good. Maybe I will have to try 5th gear :-)
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RB,
Yep. Paul is using the same gears and in fifth. He swears by it, and he's had enough wins to know. I guess the big thing for you and I is to learn how far we can push it into the corner. Once I get corner three figured out, I'll stand a chance competing for real! Should be interesting seeing how your red box compares to the black box. Be brave. Try that fifth gear! ::)
As for Todd... He's been running older tires. He may well come out faster if he gets new rubber on that car of his.
Mike
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So Mike,
Remember in the post about new car vs old car where you talked about our local dealer. All of my new parts are still sitting in his garage. He said he wanted to settle up before the holidays. He was going to let me know the final tally and bring the parts to me.
I am anxios to get the red box in. Has anyone done a black box to red box conversion? I would think there are some wire changes involved.
I am looking forward to trying the 3.58 in 5th
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Last year I removed a black vac. adv. box and put all red stuff. Very nice to install the red box only has a power and ground wire to the car the rest are to the coils and pick up. I cut a ton of wiring out when I did the switch. Did the car run better? I dont know I put a sealed motor in that was set up for the red box, so I set up the car. I never drove the car with black box on it. I took out a stock motor and saved it as a spare.
Dave
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I still run the black box, although I know most people are switching to red. I guess my only question is...Would you rather have something built by Yamaha that was designed for the engine, or something built by 600 as an aftermarket upgrade. I dont know. Being a service manager for the years I was, I saw my share of problems with non factory electrical products.
Just my 2 cents...
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So Mike,
Remember in the post about new car vs old car where you talked about our local dealer. All of my new parts are still sitting in his garage. He said he wanted to settle up before the holidays. He was going to let me know the final tally and bring the parts to me.
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So he never got in touch with you yet? I would have thought that he'd want to settle up with you quickly so he wouldn't have to carry the cost for long.
Let me know how the prices turned out. I can only go on hearsay since I haven't as yet ordered parts from him. Some have complained that he never seems to know the price before hand. It'd make me a little nervous ordering parts without having some kind of a clue about prices. Especially on a large order. Did he have pricing for you before he went down to get them?
Thanks,
Mike