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5th gear boosting, MYTH or FACT??

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Old 03-30-2006, 01:09 PM
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Default 5th gear boosting, MYTH or FACT??

well i just wondering on this topic, and seeing other searches, ppl say its bad to boost in 5th that the cylinders get too hot and u start breaking ****, and other say they have been doing it for a while and no problems, saying its in the tune, but also too much load on the engine can start breaking **** down also, just wanted your guys input on it, going to be boosting VERY soon. thanks guys
Old 03-30-2006, 01:21 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

I try to avoid boosting 5th gear because the longer you are in boost, the EGT is probably going to become higher therefore causes denotation. On the other hand, if the engine is in good condition and the tune is up to bar and keeping your eye on all the gauge reading and is where it should be than i dont see a problem boosting fifth.

I peg fifth gear for a long period of time when i was racing against an s2000 and everything was fine afterward, was running on a dinky greddy 18g tho. I dont know if i feel comfortable pegging fifth with my sc34 now
Old 03-30-2006, 01:44 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (StolenTeg)

for what I've heard is that you shouldn't be in boost for long then around 15 sec at a time in each gear. 1st through 4th your cool but 5th you might not want to do it for long time. The EGT will go up and you'll mess something up.
Old 03-30-2006, 02:41 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (wickedEG)

i was racing a 400 hp starion, before i knew it i was at 120 or so mph in 5th gear, redlining. bang pop fizz.

melted a cylinder wall.

Old 03-30-2006, 02:43 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (NotPhilTran)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by NotPhilTran &raquo;</TD></TR><TR><TD CLASS="quote">i was racing a 400 hp starion, before i knew it i was at 120 or so mph in 5th gear, redlining. bang pop fizz.

melted a cylinder wall.

</TD></TR></TABLE>

well what did u tune with?! an afc?
Old 03-30-2006, 02:49 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (LSTEG96)

wat i dont get is, if your racing on a freeway or wat not, u run out of gearing, and have no choice of going into 5th, to me it makes no sense if your tapped out in 4th, its like u pretty much lose a race cause u cant boost in 5th, either that or u extend your revs longer
Old 03-30-2006, 02:56 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

Pop it in fift for a short period of time, but there is no point of going that fast away?
Old 03-30-2006, 02:57 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

Is that a joke or what? I sometimes red line in 5th at 140+ mph on my stock engine. (Right tune required)
Old 03-30-2006, 02:59 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (Flr Power)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Flr Power &raquo;</TD></TR><TR><TD CLASS="quote">Is that a joke or what? I sometimes red line in 5th at 140+ mph on my stock engine. (Right tune required)</TD></TR></TABLE>

Is your stock engine turbo if so how much power does it make
Old 03-30-2006, 03:09 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

Its a big honda-tech myth

Your telling me if i'm at redline in 5th gear a stock evo or supra etc the engine is going to blow!!!!

Its all in the tuning, thats why a stedy state dyno is so important to get tuned on
Old 03-30-2006, 03:18 PM
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Just keep an eye on EGT, if your going to be doing alot of 5th gear pulls then get a EGT gauge just to be safe. I have a freind with a 1.8t gti all built and pull in 5th all the way to 140 mph an dhe hasnt melted a valve yet. But hes also a dick for driving that fast on public streets.
Old 03-30-2006, 03:24 PM
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Default Re: (mrbigg9032)

well hope you guys are right about tuning, jerry built is going to be doing the tuning i believe, i dont know, just seems strange to me, my homie disagrees completely. saying that not the best tune/tuner will keep it from blowing, from being in 5th, temps get too hot, and then u start breaking ****, too much of a load on the motor, temps get too hot, and i know he knows his **** even though hes a allmotorwhor3
Old 03-30-2006, 03:26 PM
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I will say it isn't the best idea. How many tuners get a chance to actually tune the car in 5th gear on the street.

You can replicate it on the dyno, but it isn't the same as on the street. I wouldn't feel comfortable doing a 5th gear pull with someone just to make sure the tune is 100% in 5th gear. This is where some sort of gear correction comes in.

But theoretically, if the tune is spot on, there should not be a problem.

My life &gt; Them winning a race
Old 03-30-2006, 03:39 PM
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why cant you replicate it on the dyno? some dynos can put load on the car and therefore imitate a 5th gear pull as if it were on the street.
Old 03-30-2006, 04:01 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

If you want to do 5th gear pulls all day, you need to retard your ignition timing and run more fuel. You will be running longer and allow heat to build up. This will increase your peak cylinder pressure as air expands when it gets warmer. So by retarding the ignition timing you are effectively decreasing the cylinder pressures and by running richer you are decreasing the cylinder pressures and minorly cooling the combustion temps. If you run fat in 5th, you can be successful.
Old 03-30-2006, 04:06 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

It's a myth...

Most Hondas blow up at 5th gear because something is lacking in their setup... Bad tune, stock internals, maxed out injectors, etc...

If the engine is going to blow up in 5th, it's going to blow up soon anyways.

It's absolutely fine to tune 5th gear on the dyno and still get a very perfect tune on a real life 5th gear on the highway. That's why you tune conservatively on the dyno so there is more buffer room for such instances.
Old 03-30-2006, 04:08 PM
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This is my 02. I know I'm not suppose to do it but I just dont give a care. Yes the EGT go up and yes there is more strain put on the motor, but what are you going to do when someone wants to do freeway pulls from 70-140. When my motor was together I did many freeway pulls and alot of those came 2 weeks ago went I went down to the supra meet in H-town.
Old 03-30-2006, 04:08 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (nowtype)

yea my friend said that same thing pretty much, except the timing part, says that the more load on the motor in 5th the leaner it gets, therefore breaking. i dont plan on like doing it every damn day or anything, just know i can when i need to, like passing someone up and not wanting to down shift or "racing" for that matter, cause i know there are ppl that go into 5th and sitll pushing it
Old 03-30-2006, 04:15 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (SPNFEDEH)

5th gear is overdrive therefore it puts more load on the engine right?
Old 03-30-2006, 04:26 PM
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All the testament to a built motor.......I was on an SAFC1 NO TUNE!!!! with blowby in all 4 cylinders and a damaged turbine wheel and I went to 150 easy for about a minute on an AFR of 12.1 or 12.2 and the damn thing wouldnt quit, I know the motor was cooked and I was racing another turbo car so I said screw it, if it goes it goes and it didnt. you couldnt see anything behind me it was smoking so badif
Old 03-30-2006, 06:56 PM
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You are not going to replicate a car moving 140 MPH on a dyno. Sure you can supply the load all day long, but you can't tune it like you could on the street. You can get it safe on the dyno and have a nice buffer and this will help prevent bad things happening in 5th gear.

I notice a huge difference going from dyno to the street. And 5th gear being a longer gear, it shows mistakes more than the other gears will. So not tuning it on the street is asking for it. This is just my experience from the cars I have tuned. By no way the end all of 5th gear pull logic.

But just think about it.
Old 03-30-2006, 10:17 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (Tony the Tiger)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">It's a myth...

Most Hondas blow up at 5th gear because something is lacking in their setup... Bad tune, stock internals, maxed out injectors, etc...

If the engine is going to blow up in 5th, it's going to blow up soon anyways.

It's absolutely fine to tune 5th gear on the dyno and still get a very perfect tune on a real life 5th gear on the highway. That's why you tune conservatively on the dyno so there is more buffer room for such instances.</TD></TR></TABLE>

yup, explained it perfectly
Old 03-30-2006, 11:12 PM
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Default Re: 5th gear boosting, MYTH or FACT?? (Tony the Tiger)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">
Most Hondas blow up at 5th gear because something is lacking in their setup... Bad tune, stock internals, maxed out injectors, etc... Very true


If the engine is going to
blow up in 5th, it's going to blow up soon anyways.

This is the small detail that people forget. Motors do get starved for oil, melt a valve and no tune will save you from that.

It's absolutely fine to tune 5th gear on the dyno and still get a very perfect tune on a real life 5th gear on the highway. That's why you tune conservatively on the dyno so there is more buffer room for such instances. Fat fuel curves are great for people that I have seen that have built motors blow there stuff because they romp on them 24/7 </TD></TR></TABLE>
Old 03-30-2006, 11:51 PM
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maybe it'd be a good idea to actually tune some 5th gear runs?

good luck finding a safe place to do it though I suppose..
Old 03-31-2006, 12:57 AM
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Default Re: (Tad)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tad &raquo;</TD></TR><TR><TD CLASS="quote">maybe it'd be a good idea to actually tune some 5th gear runs?

good luck finding a safe place to do it though I suppose..</TD></TR></TABLE>

problem is, most tuners go in 4th. and it gets leaner with each gear, so ur 4th gear dyno run might be a bit rich... and that looks bad, so i guess people dont do it? the key here would be boost by gear. just run like 1 more psi in 5th and have that tuned correctly or somethin. just a drunken idea.........


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