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Discussion Starter #1
Hey, everyone how about an informal performance comparison. Since everyone has cars in various states of hopping-up, I suggest everyone post their 3rd gear 50 to 70 mph times, along with the year of your car and what mods you have done. This will make a good comparison of which modifications work best in this "meaty" part of the rev band.

For consistancy, I suggest the following:
1) Manual trannies only, slush box guys can come up with their own system of testing. Start/finish in 3rd gear, no shifting.
2) Perform it several times until you get a good average. Times should stay within +/- 2/10 (0.2) seconds to show consistancy.
3) Post your time. Include location (altitude is a power sucker), a guess at the temperature, year of car, modifications to car.
4) Absolutely NO FUDGING your numbers. This is NOT a competition but an SR20 performance test to help everyone.

I figure this will be a good test because this is where the SR20 loves to rev and thus where we are the most interested in gaining HP. Differences in tires (traction) would be virtually nil. The speeds for this tested are easily obtained on ordinary highways without scaring the other drivers. This should also help others in identifying if their car is in the proper shape of tuning by having a handy "yardstick" to gage their car. Slipping clutches would also be easily identified.

I have a BONE stock 95 t. It will make a good beginning point to compare your times to.

Post your interest and/or your times.
 

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95Gee20Tee said:
3rd gear 50 to 70 mph times
6.28 sec
6.24 sec
6.36 sec

Less than 100 ft above sea level
43 degrees F
dry concrete, flat smooth and straight
traveling @ 50mph - start time as I instantly go WOT - end time as the speedometer crosses 70mph
93.5 G20
stick
no leather
no sunroof
not touring
no mods
cargo = me + 1/2 tank of gas + bowling ball and shoes, drill, socket set
 

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Good idea, but it's difficult to judge if a road is dead flat and this can make more difference than most variables. Average of 2 runs on the same road in opposite directions would be better. It will also help eliminate windspeed errors. By the way, I've calibrated my speedo and 70mph on the clock is really 68mph, but knowing Nissan most speedos will read the same so the test is still valid for comparison purposes.

Doubt that I'll be able to do the test for a while round here (Kent, U.K.) the roads are too busy and roadworks/cones everywhere.
 

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Discussion Starter #5
Level road

You're right on that point, two way averaging would be better. I'll leave it up to the individuals to try several different roads and average those readings if they are close enough in time.

Thanks trbobrk for the first readings. It is good to see less than .1 second consistancy.
 

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Discussion Starter #6
First times

I timed mine but the times were all over the place

1: 6.64
2: 7.14
3: 5.95

They were not back to back, so that could be some of the variation.

Temp: 60-70
Alt: Sea level
Wind: little
MOds: None, 100% stock 95t
Fuel: full tank
 

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How are you testing this, cruising at 50 then punch it, or start from say a light, and time it on the onramp as you go from 50-70 under constant acceleration? from the looks of it you guys are doing it from a constant 50mph, then mash it to 70? I think more up a gear would be better... 20mph isn't that much in 3rd gear? what about rpm based tests rather than mph (or kph). Maybe 2k-7k in second, or something like that? something that can be legally done on say a highway on ramp, 7k in 3rd would be close to 90mph, the highest speed limit near me is 55, unless i drive a little ways, then i could hit 75mph interstate, but there are no onramps around there. What do you think?

I can tell you my 1/4 mile time right now... (look at the sig.)
 

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Discussion Starter #8
more info...

I can tell you what seems to be the most consistant for me; Double clutch down to 3rd gear, slowly SLOW DOWN (about 1 mph per every few seconds) to 50mph, right when 50 is hit go WOT (wide-open throttle) and press start on your stopwatch, as you reach 70, push stop as the needle crosses.

The 50-70 works well for me where I live. Let me know what you come up with that works well for you. I just wanted something WE ALL could do easily to compare performance. Maybe answer questions like: Should I do the header or CAI first? Does a Greddy MX make any difference? Testing by various members with various modifications on the same test can help answer these questions.

I just tested mine again today and got some good consistant numbers.
6.19
6.27
6.28
6.25

Conditions:
60 deg F, half tank, windy but from side

Mods:
NONE

Someone with some mods get use some numbers. CAI, header, 91 cam would be nice to see the gains.
 

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Re: more info...

95Gee20Tee said:
I just tested mine again today and got some good consistant numbers.
And they are very simmular to mine. I test mine agian now that my clutch is fixed, it was slipping a little, don't know how much that effected it.
 

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Re: more info...

95Gee20Tee said:
Conditions:
60 deg F, half tank, windy but from side

Mods:
NONE

Someone with some mods get use some numbers. CAI, header, 91 cam would be nice to see the gains.

Let me see... I have similar mods to those, however my "testing" conditions would be close to 3000ft and about 100 degrees. I guess I could try this at night, say like right now (11:00) when it's only 80 outside :-\ But I still don't feel this is a very good test for overall power output, the rpm range just isn't large enough.
 

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Discussion Starter #11
altitude/temp corrections

I'm sure there is are some math computations that can be done to correct for the altitude and temperature differences. I'll get with C&D, R&T or SCC and see if they have some rough corrections.

You're right on the RPM range issue but I figure the broader we go the more difficult it will be for the Average G-man to get numbers. 2nd gear from say 30 mph to 60mph might be a good test OR 3000 - 6000 rpm. Let's get what numbers we can on this and then come up with a second test to see if the numbers (% difference) for the various mods compare well between test. I would expect the numbers at LOWER rpm to be similar between stock and modified but as the rpms build the differences will become more and more apparent.
 

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I just got some numbers also.
3.75
3.82
3.78

This was done on my SR20DET-powered G20. It has intake, 3" exhaust, lightened flywheel, JWT clutch, underdrive pullies. Done at 4,000 feet, half-tank of gas, 85 degrees, 1 passanger, at stock boost (7psi)

I did another run at 10psi and got these numbers
3.02
3.08
3.06

Same setup - half tank gas, 1 passenger, 4,000 feet, 85 degrees
 

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Re: altitude/temp corrections

95Gee20Tee said:
I'm sure there is are some math computations that can be done to correct for the altitude and temperature differences. I'll get with C&D, R&T or SCC and see if they have some rough corrections.

You're right on the RPM range issue but I figure the broader we go the more difficult it will be for the Average G-man to get numbers. 2nd gear from say 30 mph to 60mph might be a good test OR 3000 - 6000 rpm. Let's get what numbers we can on this and then come up with a second test to see if the numbers (% difference) for the various mods compare well between test. I would expect the numbers at LOWER rpm to be similar between stock and modified but as the rpms build the differences will become more and more apparent.
There are elevation calculators online too.

Well you figure that a good mod might take a couple tenths off a 1/4 mile time... when you only take a 20mph range that couple tenths turns into even less of a difference. The best would be compare 1/4 mile times (since this will be taken at a track, rather than on the street) that'll take everything into affect (including the launch too :*( ) You'll also have more than just the time, you'll have a mph too.
 

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Discussion Starter #14
WOW, now those are some numbers...

g20ps said:
I just got some numbers also.
3.75
3.82
3.78

This was done on my SR20DET-powered G20. It has intake, 3" exhaust, lightened flywheel, JWT clutch, underdrive pullies. Done at 4,000 feet, half-tank of gas, 85 degrees, 1 passanger, at stock boost (7psi)

I did another run at 10psi and got these numbers
3.02
3.08
3.06

Same setup - half tank gas, 1 passenger, 4,000 feet, 85 degrees
SMOKIN' !!!

I made a few more runs over the past couple months with my only mod being a Borla muffler. Numbers remained the same though at higher temperatures.
6.28
6.25
6.30
sea level, 90 deg F, 3/4 tank.
My numbers seem to have stabilized by approaching 50 from below VERY slowly, then go WOT right as it crosses 50. This method probably shaves off a 1/10 sec but it seems more consistant then when DROPPING to 50. I guess the DROP rate can make for large variations in time.
Anyone out there have just a couple mods? We have times for NO MODS and full BLOWN (literally) mods.
 

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Discussion Starter #15
17 degree timing mod

Hi All, I did my first real performance mod and got some numbers to compare.
If you read the previous post, my stock 95 G20t would do about 6.3 seconds average on the third gear 50-70 test.
I did the 17 degree timing advance about a week ago and immediately noticed an improvement. I finally tested the improvement yesterday and today. Here are the results:
6.06, 6.20, 5.95 yesterday (75 deg, 1/2 tank)
5.78, 5.95, 5.88 today (65 deg, full tank)

A BIG measureable improvement, 0.2 to 0.3 second improvement.
Next week comes the HotShot CAI. I'll keep you posted.
 

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Originally posted by JustinP10 :
something that can be legally done on say a highway on ramp, 7k in 3rd would be close to 90mph,

7K in 3rd close to 90mph? If this is true my car is way off because in 3rd at 7K i'm doing around 110

Maybe someone can clarify, oh yeah and sorry to get on a tangent
 

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Hey,

I'm not sure if your figures are accurate.
At 7000RPM in THIRD gear the p-10 G's should be going about 90-95 MPH or so. I believe at the 7500 RPM redline, we are around close to 100MPH. Justin P10 is just about right on the money....

Are you sure you are in third?
Was your gearing changed?

If you are indeed correct with your car doing 110mph at 7000RPM in Third, than you have some seriously high gearing...that would totally effect your acceleration (slower).

Let me know, I'm curious.
 

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Maybe there's something fucked up with my speedometer that's telling me i'm going faster than i am, but now that i think about it i've passed those electronic police speed signs that tell you how fast you're going and I've been UNDER what the sign said. I.E. i was going 25 and the sign said like 28. But I'm positive, and with people in the car at 7500 rpm i've been doing (from what I can see) 114mph in 3rd gear. I'll check it out tonight ;)
 

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BTW i don't think any of my gearing has been changed, i bought the car used with 101K on the clock, so stuff may have been done to it, but it wasn't modified in any other way, except for the three different brands of tires it was sporting :surprised And i have the stock size wheels/tires on it so i don't know.
 

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Discussion Starter #20
move these last several post...

Back on subject...
Anyone else have any 50-70 times? Someone with a header, exhaust, cam and CAI would fill in the current data nicely.
 
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