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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: micahadams on September 20, 2009, 11:53:28 pm

Title: 454 RPM shift point
Post by: micahadams on September 20, 2009, 11:53:28 pm

I just bought a 84 C30 with a 454/400. It came with a tach and I am noticing its cruising at 3000 rpm going 65mpg on the freeway(4.10 gears) and will shift from 1-2 around 4200 and 2-3 at 4000. I know its a BB, but that seems like a very low rpm shift. I am wondering what other 454/400 are shifting at?

Title: Re: 454 RPM shift point
Post by: VileZambonie on September 21, 2009, 04:56:45 am

Are you talking wide open throttle shifts?

Title: Re: 454 RPM shift point
Post by: Chevalade on September 21, 2009, 07:17:32 am

3000 @ 65 is screaming for a bb on the highway. You should be sitting around 1800-2100.

But as far as shift points depends on throttle usage and converter.

Title: Re: 454 RPM shift point
Post by: Donut on September 21, 2009, 10:54:59 am

Those shift points are about what mine are with 4.10's.
(smallblock, K20, WOT.  Roughly.  Part throttle is about 2500-3000)

Title: Re: 454 RPM shift point
Post by: malibu795 on September 21, 2009, 08:12:00 pm

Quote from: Chevalade on September 21, 2009, 07:17:32 am

3000 @ 65 is screaming for a bb on the highway. You should be sitting around 1800-2100.

But as far as shift points depends on throttle usage and converter.

not really

84 C30 i had came with 4.10 and 235/85/16.. when the tires were bald 65@ ~3000 and new tires was 70@ 3000rpm with a 454/400 setup.

WOT shift point sound about right for a stock th400
the stock cam in those is done makeing power by 4000rpm as well.

part thottle shift point 1-2 was less then 10mph and by 30mph i was in 3rd

Title: Re: 454 RPM shift point
Post by: micahadams on September 21, 2009, 10:20:19 pm

Malibu, thanks for the info. That was what I was looking for. I used to have a 86 c20 w/ 454/400 but it didnt have a tach so I never paid attention.

Thanks again