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Discussion Starter · #1 ·
Just wondered if anyone has a slick way to trick the fuel cutoff at 7400 in all gears.
 

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Discussion Starter · #4 ·
Oh I get there alright. Have not had it there in 5th yet but it wiil do it in fourth. I just am looking at the future when I crack its chest and pour some money down the hole. And I know it is not a busa and I don't want to buy one. I am just a sneaky old gear head enjoying my retirement. I like sleepers.
Bob
 

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The 7400 rpm limiter is hard coded in the ECM. I don't think a TEKA tuner can even remove it or change it, but I'm not 100% sure. The easiest way to do it would be to devise something that alters the tach signal so the ECM thinks it's turning less rpms than it actually is, but that would also mess up your timing and fueling. A TRE just makes it think it's in 4th gear even when it's in 5th, so it uses the same 7500 rpm limiter in both gears.

I'm not sure you would want to go a lot higher, as it peaks on hp below the 7400 rpm limiter. Plus those are some big pistons to be turning much faster.
 

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Discussion Starter · #7 ·
I know it is just some huge ol tomato cans spinning around in there. But I come from a race background and have turned bigger pistons with longer strokes much faster. But I am just thinkin out loud and throwing ideas on the wall to see what sticks. Think about this combo. 502 chevy block bored to 4.5 inches. Use a 427 chevy steel crank at 3.75 stroke. That package with the right cam and heads will make power to about 9000 at the strip. We have a smaller bore and shorter stroke. And for sure a lighter piston. Just thinkin out loud. I just miss work now that i'm retired.
 

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Split crank can't take abuse like a single pin in a Ducati, which can spin up high. In your V-8 example, both rods are on a single pin on one of the four throws of the crank. Crank fillets are much stronger than what can fit on the 109 with its split pin crank.
 

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Discussion Starter · #9 ·
Not wanting to say your wrong becase your right. And I agree with most of what you said. The Strength of the rod journal is only as strong as the overlap, material, finish and radius. The Buick and Chevy 4.3 Billet Cranks we made were split pin and those ran twin and single turbos upwards of 1400 hp. And they spun up to the sky. The crank on a nine is not a normal split pin since it has a full circle counterweight between the pins unlike the Car cranks with out a counterweight. Also the split pin verses the straight pin on V6 buicks created so much extra harmful vibrations due to Odd fire firing order timing issues that we found the split pin even fire billets to be much more reliable than the straight pin. Sorry if I am coming off the wrong way. I really DON'T mean to. I worked for a large custom crank and rod company that did a lot of research and development and quick turnaround cranks for the auto makers new engine designs. LS1 and Viper were just two of many. We did a ton of custom billets for all kinds of racing. I was a senior Tech and helped find and fix problems and set up part packages for all sorts of racing from circle track super Mods to twin turbo drag and street cars. I just miss going to work now that I'm retired. This board is my place to talk shop. Hope you don't mind my ramblings.
Thanks
Bob
 

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Screamn, there's nothing we like better than talking shop. A lot of ideas on here came from folks theorizing about what could be done, and then someone went out and did it. And we all learn from each others past experience, training, or just school of hard knocks learning.

I'm sure someone somewhere has figured out how to raise the limiter, they just haven't told us about it yet. :D
 

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I would think the engine computer would have to be cracked to raise the redline. You could surely add fuel with a pc5 but that won't do any good if the factory map limits rpm. I had the same problem with my rocket, I needed to raise the redline by 2k rpm. Nobody has the late model computer hacked so I bought one and a partial harness from a older model. Talk about a nightmare situation for something that should be so simple to change.
 

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There's only one person that i know of that had a 9 that redlined past 8 grand.
 

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The only reason to delay the rpm cutout (say to what like 8k or 8.5k)?
I don't see the advantage. Give me a reason. :dontknow: :p Unless the Dyno show's that the best numbers are aproching the 7.2k rpm. already. Still going to be mighty hard on the 109 mill. if ya manage to do it :doorag:
 

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The only reason to delay the rpm cutout (say to what like 8k or 8.5k)?
I don't see the advantage. Give me a reason. :dontknow: :p Unless the Dyno show's that the best numbers are aproching the 7.2k rpm. already. Still going to be mighty hard on the 109 mill. if ya manage to do it :doorag:
It's not just that. Far from stock motor. Removing the rev limit on a stock motor won't do anything. Need to set cams up to bring the power with it.
 

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Discussion Starter · #18 ·
You bet I did. I bought a PCV with the Ingition Module. It will allow an 8000 rpm limit. When I go inside I am going to be dropping rotating weight. IE cut the crank to a semi counterweight and lose most of the center full circle. Then eliminate the balance shaft weights. New pistons with stronger different style rings and lands and use pin buttons with an oil ring groove. This is to allow me to put a turbo on the motor along with the bigger valves and porting. I should have some new cams ground as soon as I have my port airflow readings. I am going to port the heads myself and will post the process and readings as I go. But that is "LORD" willing the plan. A Turbo-Nitrous VZR1800. Very limited street. And while it is apart I will be looking at reversing the rotation on the trans input shaft. R&D said the trans wont care and they can undercut the coast side of the gears if I spin it backwards. If I can do that then I can machine a sprocket to mount a Chain or belt drive on a 9. I am pulling my old computer out of mothballs and It has Engine Analyzer Pro and Quarter Pro on it. I can totally build a motor and then build a bike, run it down the strip and never turn a wrench till I am positive it is the best I can do.
Bob
 

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You bet I did. I bought a PCV with the Ingition Module. It will allow an 8000 rpm limit. When I go inside I am going to be dropping rotating weight. IE cut the crank to a semi counterweight and lose most of the center full circle. Then eliminate the balance shaft weights. New pistons with stronger different style rings and lands and use pin buttons with an oil ring groove. This is to allow me to put a turbo on the motor along with the bigger valves and porting. I should have some new cams ground as soon as I have my port airflow readings. I am going to port the heads myself and will post the process and readings as I go. But that is "LORD" willing the plan. A Turbo-Nitrous VZR1800. Very limited street. And while it is apart I will be looking at reversing the rotation on the trans input shaft. R&D said the trans wont care and they can undercut the coast side of the gears if I spin it backwards. If I can do that then I can machine a sprocket to mount a Chain or belt drive on a 9. I am pulling my old computer out of mothballs and It has Engine Analyzer Pro and Quarter Pro on it. I can totally build a motor and then build a bike, run it down the strip and never turn a wrench till I am positive it is the best I can do.
Bob
So do you think this bike could ever be rode on the public street ? and if the answer is yes. Do you think it could go 5,000mi without any headaches ? IE (rebuilding something)
 

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Discussion Starter · #20 ·
Yes it can go on the street and no i doubt it would make 1000 miles without a rebuild if I am racing it everyweek as I would like to. But It is going to be more of a "Look at me" bike that I race and drive to the VA and PGR missions. It would never go on a long ride. It is a 08 and only has 3300 miles on it so it is not a long distance rider. My back won't handle it. Longest ride I have had is about 120 miles following a Hearse on the freeway at 55 mph.
 
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