RPM, what to shift at

I'll be honest, I'm kind of a noob to the F-Body world but I'm interested in knowing what RPMs would be best to shift at based on my configuration.

I've got a 1983 Z28+; this year originaly came with a 305 in it but there is a newly rebuilt 350 in it.

600cfm 4bbl carb
Performer RPM intake
Stock, heads, pitsons, cam, crank, and headers

I've also got a TH350 in it with a shift kit


The above confiuration is how I bought it and since the TAC was originaly set for a 305 I'm not sure what I should shift at. Also, any suggestions on what mod would be best from here.

(Right now I'm shifting around 5,500 ... but am I selling myself short?)

Thanks!

Oh yes, and my timing is 10 degrees BTDC

It's gonna vary, and without knowing where your power is peaking at, its going to be hard to tell. Read this article, should help. The only way to pinpoint this is with a dyno of your car.

http://www.bgsoflex.com/shifter.html

Search google too, theres loads of info there.

I like to shift at around 9500 or so.

... and I like to keep my rods intact .. but thank you for you're input ;) LOL

Stock cam, 5500 might be pushing it. What cam is in there? Your best bet is to get it on a dyno and see what your HP curve looks like and decide from there.

^When my 305 was stock I used to pull nicely up to 5500. After my cam, I would shift around 6k.

I die at 5500 and im just burning gas i usually shift 5k at the highest. Then again TPI is much different

Then again TPI is much different

Yep :D

For an accurate answer you need to put your car on a dyno and see what the power curve is. That will determine your shift point. You want as much power under the curve as you can get. Your shift point will be somewhat past peek power.

unless you got tons of power that'll just keep pulling you don't need a tach IMO

shift when you feel its not worth it to stay in this gear anymore,

you should be able to fell the point where its not making any more power and just more noise


only thing I use my tach for is so I know how fast I'm going

unless you got tons of power that'll just keep pulling you don't need a tach IMO

shift when you feel its not worth it to stay in this gear anymore,

you should be able to fell the point where its not making any more power and just more noise


only thing I use my tach for is so I know how fast I'm going



This is a very innacurate way to do it. I mean, you have to judge yourself whether your car is making power still. It's not like you go from making a peak 250hp, to 50hp, the curve goes down gradually. So by the time you decide that you aren't making enough power, and you decide to shift, you are probably already past your ideal point, in which case you've lost time from passing your peak HP, and you've also lost time from the late shift that will put you too far up your power curve in the next gear.

I mean, it is do-able, no doubt, but for optimal performace, you are going to have to get your dyno curve, and have a tach that works properly.

take it to the track. shift a 5500 than at 5300. if the et slows done go to 5600 than if it goes faster try 5700. the dyno may tell you where the power is at but only the real deal will tell you the quickest shift point. On my 305 the peak was 5300 but best et came from shifting at 5700 rpm.

This is a very innacurate way to do it. I mean, you have to judge yourself whether your car is making power still. It's not like you go from making a peak 250hp, to 50hp, the curve goes down gradually. So by the time you decide that you aren't making enough power, and you decide to shift, you are probably already past your ideal point, in which case you've lost time from passing your peak HP, and you've also lost time from the late shift that will put you too far up your power curve in the next gear.

I mean, it is do-able, no doubt, but for optimal performace, you are going to have to get your dyno curve, and have a tach that works properly.


its all about feel for the car, I know when to shift my car for optimum performance just by fell, I never look at the tach,

and I'm not about to dyno my car to get an idea of where my power is I can just tell,
I NEVER look at my tach when racing,
like I siad unless you got enough power you rev until you chuck a rod, IMO you don't need a tach