Funny mod: decreasing power!!!! Here, on the forum!!!!!!!

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DreamV4

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I was always against any mods, because people screw up their bikes, and pretty often I am the guy who has to "unscrew" them.
Recently I found suggestion from Sean Morley to downsize jets in some cases.
This is what people have to do because their "upgrades" lead to decreased engine power! I don't know what exactly does that, but this is funny.
 
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one2dmax

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This is what they have to do to get even MORE out of their upgrades. The installation of the header only gives an increase but not what they could have achieved had they done even more. The header only makes the system run richer (an effect with CV carbs) so running smaller jets helps lean it back out to get that little bit more. Don't misconstrue or take my comments out of context to try and prove a point you don't fully research.
 
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I was always against any mods, because people screw up their bikes, and pretty often I am the guy who has to "unscrew" them.

Just this line....so much going on here. Can you imagine taking anything more than a broken down weed wacker to him to have him "fix" it? Especially with the lack of logic he spouts all the time?
 

DreamV4

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OK, no problem, I didn't know that decreasing jets gets more power from engine. Getting smarter every day!!!
Just this line....so much going on here. Can you imagine taking anything more than a broken down weed wacker to him to have him "fix" it? Especially with the lack of logic he spouts all the time?
I don't fix bikes and cars for people. So, don't bring me your bike. :)
 

one2dmax

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Additional clarification and will try to simplify this. When you install any full header on a Vmax you will see a gain in power when compared to stock or slip-on systems. This is mostly due to more efficiency out of the engine (better cylinder scavenging) which is due in part to the increased size of the primary pipe work (the muffler size helps some but not the main reason) *NOTE - exhaust pipe size is critical because too large and you lose velocity. The cylinder is more "empty" because the exhaust speed (velocity) coming through the pipe work is moving faster and also this in turn helps other cylinders since it uses helping pull the next pulse out from them (google exhaust scavenging). Since each cylinder is now more "empty" it has a greater vacuum on the carbs in it's next intake stroke which in turn pulls in more fuel and air so more mix is available to create more power. SO here we are with more power then stock.

BUT, I mention that the bike needs smaller mains to get even better. The increased pull on the carbs/intake helped pull in more mixture. BUT, with no change to the intake above the carbs it's pulling in a greater ratio of fuel (thanks to the CV carb function) then it is pulling in air. THUS a richer ratio. Again you are getting more power but not what you could have. SO, by going with a smaller main you lean that out to a more ideal ratio. So, instead of gaining 3-7% from the header alone you now gain 5-10%. AND, if you go through and add in a well designed jet kit you can get another 1-3% more power (actually we tend to gain even more in the mid range with our kit due to the reuse of the factory vboost and velocity stacks in the airbox).

From another misleading post. The Vboost was not something to "Fix" a carb problem. It was done to maximize an entire RPM range by making less CFM to each carb when in lower RPM's and more CFM when in higher RPM's. A very ingenious way of keeping intake velocity throughout a large range to get the best of both worlds. Some guys like to put 750 double pumpers on their small block's and love the way it runs at 6500 and up RPM. BUT, they run like shit down low and around town due to the over carburation. If they would come up with a Vboost for themselves they could also get maximum benefit that they haven't seen before.

One final note, if you are a "car guy" and have been around awhile. There was a carb back in the day that was very similar to our CV's. This was the "Predator" carb. Another revolutionary carb that was greatly misunderstood (though I personally never ran with one either - a product of that misunderstanding of how they worked 30+ years ago).
 

V-Four

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Oh, and to fix your 92 dead lights simply pull out the partially stuck start button.

THIS lil tidbit was the BEST vmax info I got several years ago. So glad once I found what it was.

Even once fixed, still SUCH a habit, start the bike, then put my thumb next to switch and kinda 'pry, or pull the switch outward, JUST TO MAKE SURE. Lol.


Had a 78 Firebird with a lil Quirk..
Car was a CONSOLE SHIFT.
Go Turn the key to start... nothing, but rotate the steering wheel "shaft cover sleeve" counter clockwise (as if shifting further into Park), she'd fire up. (The shifter cable had stretched, just enough. (or should I say, just too much? Lol)
That One took a bit to troubleshoot.
Good times


T$
 
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Fire-medic

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I recall the Gen. II F-body GM pony cars have an electrical switch on the left-side of the steering column, working by a rod connected to the steering column ignition key female receptacle. I once had to change that switch, and it took a bit of trial and error to get the rod to move the switch innards to allow it to-start, before I tightened the switch mounting screws. Maybe your shaft cover sleeve was interfering/enabling the rod/switch?

I owned three F-bodies, a couple of '77 Trans Ams, one was a Hurst-Hatch 6.6 litre Poncho engine and it was the S.E. WS6 gold pinstriping version, yes, 'like Smokey and the Bandit.' I bought it from the original owner. That car got more attention than any car I've owned. The second was a year-old '77 T-A also a 400 Pontiac, both were automatics. Then I had a '80 Z28 which was a lot of fun too. That was the one I had to replace the steering column ignition switch (not the one you insert the key into, but the one controlled by the rod) inside the steering column sheetmetal cover.

My GMC pick-up I bought new in '09 had the key fob go-bad, earlier this year, I bought a replacement fob at Advance Auto and had it programmed, the whole thing was <$90.
 

V-Four

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I recall the Gen. II F-body GM pony cars have an electrical switch on the left-side of the steering column, working by a rod connected to the steering column ignition key female receptacle. I once had to change that switch, and it took a bit of trial and error to get the rod to move the switch innards to allow it to-start, before I tightened the switch mounting screws. Maybe your shaft cover sleeve was interfering/enabling the rod/switch?

I owned three F-bodies, a couple of '77 Trans Ams, one was a Hurst-Hatch 6.6 litre Poncho engine and it was the S.E. WS6 gold pinstriping version, yes, 'like Smokey and the Bandit.' I bought it from the original owner. That car got more attention than any car I've owned. The second was a year-old '77 T-A also a 400 Pontiac, both were automatics. Then I had a '80 Z28 which was a lot of fun too. That was the one I had to replace the steering column ignition switch (not the one you insert the key into, but the one controlled by the rod) inside the steering column sheetmetal cover.

My GMC pick-up I bought new in '09 had the key fob go-bad, earlier this year, I bought a replacement fob at Advance Auto and had it programmed, the whole thing was <$90.

Yea, Seemed so Odd to me that in an automatic, with a Shifter on/im the CENTER console, the steering column "sleeve-Y -majig still moved as if the shifter was right there on the wheel/tree. 🤔



T$
 

RadiumPHX

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THIS lil tidbit was the BEST vmax info I got several years ago. So glad once I found what it was.

Even once fixed, still SUCH a habit, start the bike, then put my thumb next to switch and kinda 'pry, or pull the switch outward, JUST TO MAKE SURE. Lol.


Had a 78 Firebird with a lil Quirk..
Car was a CONSOLE SHIFT.
Go Turn the key to start... nothing, but rotate the steering wheel "shaft cover sleeve" counter clockwise (as if shifting further into Park), she'd fire up. (The shifter cable had stretched, just enough. (or should I say, just too much? Lol)
That One took a bit to troubleshoot.
Good times


T$
I had a 61 T-Bird that had this "safety feature" that was intentional. You had to reach over with your left hand and hold the column shifter all the way to the left past park in order to start the car. A way to insure the car was in park before starting.
 

Fire-medic

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I had a 61 T-Bird that had this "safety feature" that was intentional. You had to reach over with your left hand and hold the column shifter all the way to the left past park in order to start the car. A way to insure the car was in park before starting.
That happens because of wear of components in the steering column, nothing designed into the car! The neutral safety switch no-longer is able to be aligned to allow starting the car. Your 'reach-around' (an appropriate appellation if there ever-was one!) was merely the way you discovered to overcome the worn-out parts.
 

RadiumPHX

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That happens because of wear of components in the steering column, nothing designed into the car! The neutral safety switch no-longer is able to be aligned to allow starting the car. Your 'reach-around' (an appropriate appellation if there ever-was one!) was merely the way you discovered to overcome the worn-out parts.
This doesn't surprise me. When asking the mechanic working on the T-bird (this was 20 years ago), this was the response given, that it was an intentional feature. I can say I learned to hate that car, nothing but problems from day 1 until the day I sold it (a happy day indeed). Funny thing, I had a friend recently buy a 60 and it had the same exact issue and the same "reach around" solution.
 

Fire-medic

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One of my friends growing-up, his family would buy a new Cadillac one year, and a new Thunderbird the next, for their two cars. After two years, the older car was traded. They were great to ride-in, few of my friends' families had new Cadillacs or Lincolns. We were Oldsmobile and Pontiac buyers for new cars, and we would keep them for 4 or 5 years before a trade-in. Many years later, I was given a 1970 Cadillac Eldorado with 49,000 miles, and it was probably about 20 years old, the rear seat was like a couch. Blue exterior, white leather interior.

I liked the lines of the 1961-'63 Thunderbirds. Like the 'slab-sided' Lincolns of 1961-'68, they were a great body design.
 
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