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sedan vs. wagon

3K views 15 replies 7 participants last post by  jwtarbaj 
#1 ·
Well here is whats gonna happen. Me and my friend are gonna do a drag race just to see which car is faster and who is a better driver. This is all just for fun and neither of us is gonna try and kill the other or what not. Well hear are the mods and cars. I know that some of these mods dont matter but I am gonna post them anyways.

Wagon with an automatic transmission mods: up pipe, slow boy racing turbo back, greddy boost controller set at 16 psi, ebay intake, gauges.

sedan with 5 spd mods: perrin upipe, turboxs turbo back exhaust, aem intake, turboxs utec boost set at 16 psi, bov, eibach pro kit, short throw shifter, and gauges.

I would like to hear your opinions on who you think will win. He is going to break launch it and I am gonna set the secondary limitter a 5.5 grand and launch from there. If you have any advice for either of us i would be very interested in hearing it to. Odds are we are going to video tape it so I can send you guys that too.

P.S. please dont flame me
 
#4 ·
my bet is also on the manual. simply because it's a manual. the engine for both cars are almost the same. the boost is almost equal. the mods are similar (except for the utec, which will give a little advantage in the long run, but for drags...not sure)

BUT if we are talking about both manuals, then it becomes interesting. the ratio for the 1st gear for the wagon is much higher because it provides for people who tow their weekend boats or mobile homes. i drive a wagon and i need to shift out of 1st in a matter of secconds.

so if this is a straight drag. the sedan may have an advantage, even if both are manuals.

but i stand corrected on this...
 
#7 ·
wrxloonie said:


BUT if we are talking about both manuals, then it becomes interesting. the ratio for the 1st gear for the wagon is much higher because it provides for people who tow their weekend boats or mobile homes. i drive a wagon and i need to shift out of 1st in a matter of secconds.

but i stand corrected on this...
Are you sure the Wagon has a different first gear than the Sedan? I would really doubt it due to the low production #s of the car to begin with. I'll have to check my brochure when I get home today.
 
#8 ·
jwtarbaj said:


Are you sure the Wagon has a different first gear than the Sedan? I would really doubt it due to the low production #s of the car to begin with. I'll have to check my brochure when I get home today.
yes, as a matter of fact, the difference is rather big. i got my info from the book you and your subaru impreza turbo by chris rees.

but i do want to make a clarification.

the wagons and sedans that i am refereing to are the classic wrx (from my95-my99) which are not available in the US. as for the new age imprezas, i am not too sure about the first gears.

but don't u guys in the US tow boats and mobile homes with your wagons too? that's the main reason for the difference. because the designers assume that wagon people use it to tow jet skis and stuff on trailers.

if u want to exact ratio, i need to go refer to my book (which i do not have with me now).

your WRX historian,
mark
 
#9 ·
i need to put this in before i get flamed!

alright, after checking, i realised i made a mistake.

the gear ratios of sedans and wagons are the same. i absent mindedly compared the 5MT ratios to the 4AT. my fault.

so there goes the theory about towing boats and jet skis.

To move away from the tranny, engine rating for the GC8 and the GF8 are different (260PS and 220PS respectively). however, i think the for the new age imprezas (GDB GFB), they should be similar.

finally, sorry for misquoting from Mr Chris Rees book. once again, the trannies are all the same. except for the RA and the 6 speed.

bad excuse for a wrx historian,
mark
 
#11 ·
No question the auto has different ratios. It has 4 gears vs 5 in the manual just like the STi has different ratios and it has 6 gears.

The final drive in the manual is 3.9 and it's like 4.1 in the auto too. That is to offset the lag from the auto tranny I'm sure. Higher numerical final drive ratio = faster acceleration. I fit's truly important I can put the numbers in from the 03 Brochure later today.
 
#12 ·
jwtarbaj said:
Higher numerical final drive ratio = faster acceleration. I fit's truly important I can put the numbers in from the 03 Brochure later today.
now here is some research that i did, as a good WRX historian

gear ratios

gear wrx ver III STi verIII STi verV WRX-NB STi GDB
1 3.166 3.166 3.083 3.166 3.636
2 1.882 1.882 2.062 1.882 2.375
3 1.296 1.296 1.545 1.296 1.761
4 0.972 0.972 1.151 0.972 1.346
5 0.738 0.738 0.825 0.738 1.062
6 0.842
FD 4.444 4.444 4.444 4.444 3.900

the final drive for all other WRX 4.111 (i stand corrected on this)

the FD for the WRX RA is 3.900 too. and i was told it yields a lower top speed.

so is really true that final drive ratio=faster acel?

another thing, the last gear for a 6-speed is 0.842 while the last gear for the 5 speed is 0.748. that means in terms of top speed, the 5 speed has greater potential?

for the first gears, compare 3.166 to 3.636...

does that mean we have to shift out of the first gear really quick for a 6 speed? while for a 5 speed, we can stay on it for a sec more?

can we have some authority on this?

your confused wrxloonie,
mark


(gear ratio source: issue 65 aug 2003 Option fan mag HK edition)
copyright 1998 long goal industries Limited (Hong Kong)
 
#13 ·
wrxloonie

I think that info is flawed. A higher numerical axle ratio will yield faster acceleration at the expense of top speed. The same is true in the tranny gear ratios higher number=faster acceleration but lower speed potential.

Remember there is a tradeoff for everything. You can't get something good without sacrificing something else.

As far as top gear (5th/6th) and 1st gear in STi vs WRX. There are other factors that play into this also. Axle ration, power from the engine and tranny gearing.

You should have to shift out of first in an STi sooner even if you have the same gearing because there is more power to get to the top speed faster.

Also 6th gear in a STi is 0.72 not 0.84. The top gear in modern cars is an overdrive and is really only good for gas mileage.
 
#14 ·
thanks jw for the correction.

we had our regular hangout here and one STi ver8 did show up. so i took the opportunity to ask him about his 6th gear.

and just like u said, he hardly goes that far. but when he did, he could touch 260kmh easily. that's all i need to know. :D

oh yes, btw i did a search on "gear ratios" here and in nabisco. i could not come up with anything that tells me more about the numbers and what they mean.

do u have a link to recommend, preferably something scooby specific?

e.g. what's close ratio? how to calculate top speed from the ratio (theoretically at least)? what's final drive? how to compensate for bigger wheel circumference... and stuff like that.

thanks a heap!


your wrxloonie
mark
 
#16 ·
wrxloonie said:

oh yes, btw i did a search on "gear ratios" here and in nabisco. i could not come up with anything that tells me more about the numbers and what they mean.

do u have a link to recommend, preferably something scooby specific?

e.g. what's close ratio? how to calculate top speed from the ratio (theoretically at least)? what's final drive? how to compensate for bigger wheel circumference... and stuff like that.

thanks a heap!


your wrxloonie
mark
I don't have any direct links to any info on gear ratios. I am just speaking from what I've learned in my 27 years on this planet being a car nut. Car & Driver is the mag I have read the most. I AM IN NO WAY AN EXPERT!

The numbers are pretty basic. Example 1st gear is 3.166 which means for every 3.166 turns of the input shaft the 1st gear turns the driveshaft(s) 1 time 3.166:1. I could have that backwards. So you can see it is multiplying the power. As you go numerically higher in gear # 2, 3, etc the ratio gets lower. When you get to 5th or overdrive you are overdriving because the input shaft turns less than 1 turn to turn the driveshaft 1 full turn. I hope this isn't too complicated for anyone.

Of course then the driveshafts have to be converted out to get to your wheels. That is where the differentials or axles come into play. The axle ratio is often called the final drive ratio don't know why. Any way WRX has 3.9 ratio so for every 3.9 turns of the driveshaft you get 1 turn of the axle again multiplying the power.

THere is no real way to calculate top speed from gear ratios and power etc. Drag from the air comes into play, production tolerances between any 2 of the same vehicle, engine output (which changes with the weather) etc. Too unpredictable.

There is a formula to figure out the change in wheel/tire diameter. It will cahnge the final drive or axle ratio but I do not have it. You can also calculate how it will alter the speedo readings.
 
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