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More Horsepower In 2nd Than 3rd Wtf!

Daboss

By Daboss,
in Engines & Forced Induction

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Daboss Experienced

Daboss

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Hey forum once again I call on the experts to assist me with a question I have. Car is a 95 gts-t, mods are 3.5" turbo back exhaust with split dump, pod filter, iridium plugs gapped at .7, ebc boosted up to 10 psi, and i just recently got on 98 ron fuel after using 95 for a year. Everything else stock and an afc neo but its not tuned. Neway, here is the prob got a gtech pro, and its the best thing to a dyno i have, i did a few runs and i noticed that I am having more power in second gear than throughout the entire third gear rev range. What could be causing this? Can neone tell me or give some opinion as to y second gear is reading more hp than the entire third gear. The reading was 222..6 hp at 5610 rpm in second gear and the highest hp in third was 218.1 at 5676 rpm. Thanks in advance for all help!!

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Daboss Experienced

Daboss

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You should know but since I failed to mention it this is at wide open throttle, also I noticed boosting starts for me at 2-2500rpm and is not full on till like 4000rpm does this seem correct for stock turbo with the boost turned up to 10 psi

murrayis Mentor

murrayis

Posted
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Hi,

As far as i know the G-techs measure the amount of pull aka g's, therefore in second gear it should appear slighty higher as its a shortrer ratio therefore giving it more pull as the gear is shorter and doesnt take as long to get through, But third is longer and takes a tad longer to go through the entire gear.

The last g-tech i had was useless, bought it just to compare, it told me i had 253HP in 3rd, but when i chucked it on the dyno was just over 300hp.

Best bet is to take your car to your local dyno shop and get a couple of power runs.

TailsTails Apprentice

TailsTails

Posted
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second gear = more suspension squat = gtech reads apprently larger acceleration forwards because of gravity

wind resistance = less net acceleration as well

most importantly, you're using a g-tech to measure a 2% difference and wondering why the discrepency is there. I'd be happy yo have a g-tech work that well at all.

hope that made sense.

Daboss Experienced

Daboss

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second gear = more suspension squat = gtech reads apprently larger acceleration forwards because of gravity

wind resistance = less net acceleration as well

most importantly, you're using a g-tech to measure a 2% difference and wondering why the discrepency is there. I'd be happy yo have a g-tech work that well at all.

hope that made sense.

Yea I undersatnd what you are saying but shouldn't third read a higher horsepower figure seeing it is a more powerfull gear i mean 218 is the highest I got to redline? I figured you would get a higher horsepower readin in third seeing as when you go to a dyno thats the gear the would use to tune and get max hp out of.

Bumblebee Experienced

Bumblebee

Posted
Posted (edited)

more powerful gear??? wtf is that suppose to mean.. its a gear.. it only transmit power frmo the engine.. which is the same despite what gear ur in...

Gears are just a multiplier of torque in most cars from 1st to 3rd... 4th is usually a 1:1 ratio which is why dyno runs r done in 4th usually or the gear closest to to the 1:1 ratio.

2nd is usually like 2.5:1 which means that if ur shitbox makes 100hp @ engine, then ull have 2.5 times that coming out from the box. 3rd is lower still so it will register lower

u tryin it in 2nd or 3rd is just pointless. get to a real dyno and ull see how much u really make

Dynos dont use 3rd champ. and if a paticular shop does.. i wouldnt go there.. means theyre shitty dyno doesnt go past certain speeds = cheap bastards

Edited by Bumblebee
Daboss Experienced

Daboss

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more powerful gear??? wtf is that suppose to mean.. its a gear.. it only transmit power frmo the engine.. which is the same despite what gear ur in...

Pardon my use of terms but I meant smaller ratio.

Gears are just a multiplier of torque in most cars from 1st to 3rd... 4th is usually a 1:1 ratio which is why dyno runs r done in 4th usually or the gear closest to to the 1:1 ratio.

2nd is usually like 2.5:1 which means that if ur shitbox makes 100hp @ engine, then ull have 2.5 times that coming out from the box. 3rd is lower still so it will register lower

Thanks for that bit of info

u tryin it in 2nd or 3rd is just pointless. get to a real dyno and ull see how much u really make

Dynos dont use 3rd champ. and if a paticular shop does.. i wouldnt go there.. means theyre shitty dyno doesnt go past certain speeds = cheap bastards

Another lesson learned, Cause I saw a few so called tuners over here tuning in third which they said third or fourth will b okand also one was road tuning a car in third as he didn't have access to a dyno

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