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Discussion Starter · #1 ·
I specified this option when talking to Brian Herter (pcmforless) but now not so sure. Not that I need it often.

I have 1.6 RR & beehive springs and other stuff, can I theoretically rev beyond 5000? I've hit the limit maybe once or twice.

I have 2 PCMs I want tuned differently, one for 28" tire, 93 Octane

the other plan to tune for maybe for 29" tire, 89 Octane and possibly remove the 5000 rev limit.
 

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I believe most of the guy's go to 6K + with the spring & rocker upgrade.
 

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I specified this option when talking to Brian Herter (pcmforless) but now not so sure. Not that I need it often.

I have 1.6 RR & beehive springs and other stuff, can I theoretically rev beyond 5000? I've hit the limit maybe once or twice.

I have 2 PCMs I want tuned differently, one for 28" tire, 93 Octane

the other plan to tune for maybe for 29" tire, 89 Octane and possibly remove the 5000 rev limit.
The Stock Cam is fairly tame even with 1.6 RR's.
All I did was add the 1.6 rockers and Zero Lashed the Valves.
I am using the Stock Springs on both cars.

The Cam is all done in at 5400rpm...going through the traps at 6000rpm is not unusual winding it all out.
Save the huge effort of new springs for a cam swap.

If you want it all install a manual lock TQ switch.
Consider locking the TQ at 5700rpm which will feel like a 4th shift.

What gear Ratio are you considering?
With 28 inch tires you will need 4.11's

Actually I use the BH87 Octane tune.
Had the 93 but needed to add 100 octane to stop the pinging.
Did not see any difference in performance.

Dan
 

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Discussion Starter · #7 ·
I don't have stock cam.
I don't "race" or anything but it's nice to feel it's performance once in a while. I think I hit the rev limiter twice in the last few months. I left it up to them to set the rev limiter to 5K, I didn't fully understand if I needed it or not. I will remove it. I have 2 computers so I can experiment with different settings.

I am running 3.73 and 26.3" tires at the moment, which puts me at a slightly lower ratio than 3.73, maybe 3.80. I like it. Not bad at all. The tires are fine, I just don't like the way they look, too small and it seats too low.

With 28" tires, it shouldn't really change all that much, go up to 3.6xx or so. I can live with 3.6x gear ratio in a daily driver. But you are right - if I wanted max performance, I would chose 4.10 gears.

In any case, this answers my main question.
 

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........I have 1.6 RR & beehive springs and other stuff, can I theoretically rev beyond 5000.......
I normally get to the 6800 RPM range when I race......and I use the Pro-Magnum RR's.

With the Beehive springs (as long as you have no issues with unusually heavy valves or an extremely high lift cam) you should be able to get to 6300 to 6500 RPMs with no problems.

5000 RPMs? That's only an issue for stock springs ;) .

KW
 

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on stock cam/heads with stiffer springs and 1.6rr my car shifts at 5700 and redlines 6200
 

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on stock cam/heads with stiffer springs and 1.6rr my car shifts at 5700 and redlines 6200
Your stock cam makes power to 5700 RPMs :eek: ?!?!?

Wow!

KW
 

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I forget what brian set my rev limiter at. I have 1.6rr lt4 cam and behive springs. I over revved it a couple times. not sure if it was the reason my studs backed out or that some of the ball ends on my pushrods broke off, but i am not sure what elese would have caused it.
 

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Your stock cam makes power to 5700 RPMs :eek: ?!?!?
Wow!
KW
I shifted mine at 5800 for best ET's with the Yank SS3600. Less converter, and he would DEFINTELY want to shift that high at the strip, maybe not on the street.
 

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Yep.

I used to shift my stock cam/springs/rockers car at an indicated 6000RPM on the 1-2 shift, then slightly lower on the 2-3 & 3-4 shifts. The engine was making more power at 6000 than it was under 4000 ;)
 

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I thought you would know that KW. It's not about shifting it where it makes peak power, it's about shifting it, so the RPM's don't drop under the powerband when it hits the next gear. :)
 

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The Stock Cam is fairly tame even with 1.6 RR's.
All I did was add the 1.6 rockers and Zero Lashed the Valves.
I am using the Stock Springs on both cars.
Yikes. Don't the valve springs float? My cars felt like they were floating by 4500.


Actually I use the BH87 Octane tune.
Had the 93 but needed to add 100 octane to stop the pinging.
Did not see any difference in performance.

Dan
It does seem like Herter's tunes are too aggressive on timing.
 
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