According to the generally accepted rules of thumb to decrease the zero to 60 mph time by 0.5 seconds would require close to 60 - 80 more horsepower/pound feet or a 500 pound minimum weight reduction.
While I believe 0.2 seconds is possible with every thing you mention in combination.
The relative low 1st gear multiplication mean you don't hit 4,000 rpm until past 30 mph so flow improvements can't occur until more half the elapsed time has past.
Most improvement between 30 and shift to second.
But then again I haven't experimented with any Q later than 95 so you might be right.
Have you checked at 100F ambient to see if there is any down side to mods?
Squeezing Out More Horses
My times were all made using the new version GTECH computer, and although it is supposedly more accurate than the previous model, I have not tested it against other timers. Even if there are errors, however, at least all of the errors were similar. I will definitely time more runs at different ambient and under-hood temps. I modified my POP air filter area to confine its air space from the hot engine compartment, but it is not completely air tight. I saw another conversion on this site where the intake tube was punched through the sheet metal. That seems like a reasonable soultion for getting more cold air. But, as you are alluding to, the cold air is only part of the problem. In general, it would be great if I could keep the whole engine cooler as the ambient rises into the triple digits (as it certainly will in the California summers).
Going back to your point about the logical conclusions for 0-60 times, I agree that by the book, it seems like my gains were a bit high. Actually, they were more than even I had expected. Other possible variables could be the psychological factor in my pegging the gas pedal. The car now has a nice and deep sounding growl as it winds up, and it seems like it really pulls after 5K. Since I can't imagine that the pipes have gained my low end, then I have no idea where it is coming from. I am not sure that my GTECH computer will measure a 0-30 accurately. I will speak with the manufacturer and check.
Going back to your point about the logical conclusions for 0-60 times, I agree that by the book, it seems like my gains were a bit high. Actually, they were more than even I had expected. Other possible variables could be the psychological factor in my pegging the gas pedal. The car now has a nice and deep sounding growl as it winds up, and it seems like it really pulls after 5K. Since I can't imagine that the pipes have gained my low end, then I have no idea where it is coming from. I am not sure that my GTECH computer will measure a 0-30 accurately. I will speak with the manufacturer and check.
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Chally
- Posts: 445
- Joined: Tue Apr 30, 2002 12:17 am
- Car: '94 Infiniti Q45
2002 Nissan Patrol 4.8L
2013 Citroen C4 (economy)
Figures from AGM's Q, 94 model.
Standard Rear wheels = 168hpaddExhaust from Header back = 210hpaddUni Chip mod = 210hpaddNew modified headers = 242hp.
His Tractine Effort went from 1120 to 1300.
Yes, you can get more HP from exhaust mods.(we also don't have Pre-cats here in Astralia)
NB: all done with engine in place. AGM has since supercharged his engine, so these figures are now a little low.
Standard Rear wheels = 168hpaddExhaust from Header back = 210hpaddUni Chip mod = 210hpaddNew modified headers = 242hp.
His Tractine Effort went from 1120 to 1300.
Yes, you can get more HP from exhaust mods.(we also don't have Pre-cats here in Astralia)
NB: all done with engine in place. AGM has since supercharged his engine, so these figures are now a little low.
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
My 90Q has 242 RWHP oem everything except the Dynan ecu reprogram [JWT copy?] going back to stock ecu it has 218 RWHP..........we dynoed the engine multiple times and multiple years [ over the last 7 years]..........no real effect below 3000 rpm.
That said we don't get any call for improvements on 96-2001 Q, never interested me personally. Hopefully someone can come up with a series of improvements other than just swapping the engine and transmission for a 2003 Q unit.
That said we don't get any call for improvements on 96-2001 Q, never interested me personally. Hopefully someone can come up with a series of improvements other than just swapping the engine and transmission for a 2003 Q unit.
