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View Full Version : What do you think i should shift at?



Firebirdjoe
01-30-2010, 04:23 PM
Stock heads cam and bottom end what do you guys think i should be shifting at?

Joker Z28
01-30-2010, 04:38 PM
I think 61 or 6200 should be fine.

RoadHawk
02-04-2010, 06:57 PM
Youv got longtubes so If your in a tight run You could bring her up to 6300. Not reconmended tho without a tune. With Gears, seen em do it to 6500:pinch:... Id stick with what he said 6200

JPack
02-04-2010, 07:05 PM
Do you want to rebuild the motor when u spin a bearing? 6k would be highest I would go on a stock engine

RoadHawk
02-04-2010, 07:15 PM
With Lt, gears shifting at 6450 it was performing a little better at the track(not mine). Iv ran my motor up 6100+ evertime if raced or tracked it for 60k miles now, have never had a problem, till now with my Recent drop in oil pressure, oil coming from intake manifold, and some ticking valves. Took the abuse for 65Kmi and just starting to have problems.

jaysz2893
02-04-2010, 07:34 PM
1996 Pontiac Firebird M6, Pro 5.0 ,Welfare CAI, Magnaflow Catback, Longtubes, 160 thermostat, BMR torque arm and lower control arms, TB bypass, e-cutout, on my second motor, third clutch, and third fuel pump.


when it goes BANG you have gone too far.. I have stock motor with LT's and i dont go past 6000. I am a wuss...

5POINT7
02-04-2010, 07:39 PM
when it goes BANG you have gone too far.. I have stock motor with LT's and i dont go past 6000. I am a wuss...
Same here I never go over 6k

~chipsahoy~
02-05-2010, 08:56 AM
Just take it up to 7200....you'll be fine....

:)

YZF
02-05-2010, 01:21 PM
With those mods you'll start losing power pretty hard around 5500 (comparing this to my dyno, with similar mods) so it's pointless to run it past 6k rpm.

Firebirdjoe
02-05-2010, 02:11 PM
when it goes BANG you have gone too far.. I have stock motor with LT's and i dont go past 6000. I am a wuss...
Hahaha yea thats why im asking. But the motor was pretty beat by the previous owners neglect and abuse.

RoadHawk
02-06-2010, 02:11 PM
With those mods you'll start losing power pretty hard around 5500 (comparing this to my dyno, with similar mods) so it's pointless to run it past 6k rpm.

2412 stock everything muffler delete hyprtech

YZF
02-06-2010, 05:10 PM
2412 stock everything muffler delete hyprtech


I was going off what's in your sig. "Pacesetter LT headers, Ps orY, slpChamberedcatback"

My cars powerband went up a few hundred RPM with the LT's

RoadHawk
02-06-2010, 06:56 PM
I was going off what's in your sig. "Pacesetter LT headers, Ps orY, slpChamberedcatback"

My cars powerband went up a few hundred RPM with the LT's

Excellent, I Have yet to have it dynoed since intalling the LT and orp. (Waiting for a tuner) do you have a dyno grah? where do you peak power?

purple 95 z28
02-06-2010, 08:31 PM
Stock motor stops making power at about 5600 rpm if I remember correctly..... so why rev much past that? If I were you I would shift at 5800 rpm, that way with the rpm's you lose when you shift you will be right in your power band again.

YZF
02-07-2010, 12:48 PM
Excellent, I Have yet to have it dynoed since intalling the LT and orp. (Waiting for a tuner) do you have a dyno grah? where do you peak power?

Just had it dyno'd a couple weeks ago. The red wavey lines are my stock dyno pulls and the smooth lines are with my current bolt ons.
2420

AChotrod
02-07-2010, 03:42 PM
I always shifted at 6100 with bolt ons

1fasstLTx
02-07-2010, 04:21 PM
Im shifted at about 6100 as well when I had just longtubes

1963SS
02-07-2010, 05:53 PM
I'd also say that 55-5700 should be all you need. That's where you are making the most horsepower and there is no advantage to going higher. Why flog a dead horse?

AChotrod
02-07-2010, 06:13 PM
you need to shift past peak, so when you shift it ends back at peak HP. :)!!!

YZF
02-08-2010, 01:45 PM
you need to shift past peak, so when you shift it ends back at peak HP. :)!!!

Ditto!

1963SS
02-08-2010, 06:10 PM
you need to shift past peak, so when you shift it ends back at peak HP. :)!!!

Sorry, but I disagree. I've found that if you shift just far enough above your peak horsepower to drop your RPM's back to your peak Torque I've turned better times. . Say you have a 220 first gear like the old Muncie's you will also have a 1.64 ratio in second. That's about a 26% difference. Say you have max horsepower around 5500 and max torque at 4200. If you shift at 5500 your RPM's will drop back about 26% or so to 4070 RPM. That's below your peak torque......not good. However if you shift at 5700 RPM's, after the 26% you will be at around 4200. Peak torque. Your car pulls hardest at peak torque and will continue to pull hard to peak horsepower. Do the percentage for your other transmission ratios and you'll find that the shift points aren't always the same. At least that's what works for me and as always. IMHO;)

blackbird1084
02-08-2010, 07:10 PM
I agree. When I first took my car to the track after I put the 355 in I tried letting it shift it's self at 6500. By doing so my car only ran 12.6's @108. By simply shifting the car myself at 7000 my car ripped to a 12.26 @111.1 and later at 08's shootout a 12.16 @110.8. All I did was change my shift points to where it felt like it still pulled as I know there's no way my car with a little 355 and a cc306 makes peak power past 6500.

RoadHawk
02-09-2010, 04:55 PM
Hahaha yea thats why im asking. But the motor was pretty beat by the previous owners neglect and abuse.

Well if it was neglected and its abused. I wouldnt rev it past 5500 until you rebuild it.