whats red line for a 3.2

[cmcfaul]

Pretty sure my 89 Carerra has a chip as no rev-limiter kicks in at red line and it seems to want to go further. At what point will valves float or other bad things happen if taken past red line under power (not forced as in a bad downshift).

I miss the extra 1,000 RPM's (7300 red line) on the 2.4 E

Chris
89 Carerra

[Trakrat]

A rev limiter would have to be installed.... I don't believe these cars came with one. And a chip wouldn't be able to do anything, as the throttle isn't electronic.

Unfortunately you can't put a specific rpm value on what is considered bad and when valve float or other engine issues happen.

But for what it's worth... the red line is about 6750. Anything higher than say 7k, and you risk having your pistons kiss your valves.

[cmcfaul]

Good to know. Indicated is about 6300 I believe. So going a little deeper is not terrible. Would think the engine management system would include a rev limiter. My older Porsche had a spring in the rotor that mechanically cut spark at 7300. Noticed mine does not.

Chris

[Bill Verburg]

Originally Posted by cmcfaul

Pretty sure my 89 Carerra has a chip as no rev-limiter kicks in at red line and it seems to want to go further. At what point will valves float or other bad things happen if taken past red line under power (not forced as in a bad downshift).

I miss the extra 1,000 RPM's (7300 red line) on the 2.4 E

Chris
89 Carerra

hp max is 5900

revs are electronically limited by the chip in the DME to 6520+/-50

[cmcfaul]

that's what I figured.

[Tippy]

Originally Posted by Trakrat

A rev limiter would have to be installed.... I don't believe these cars came with one. And a chip wouldn't be able to do anything, as the throttle isn't electronic.

It should fuel cut.

[Trakrat]

Originally Posted by Bill Verburg

hp max is 5900

revs are electronically limited by the chip in the DME to 6520+/-50

Doh! I always get it backwards... I meant 6570, not 6750.

[Trakrat]

Originally Posted by Tippy

It should fuel cut.

hmmm... didn't think it would be smart enough to do that.
So does it completely lock up the injectors and starve the engine or is the fuel cut somewhere else..(fuel pump, etc....)??

Does this essentially kill the engine when it hits redline?

[Driven97]

I tapped my rev limit a few times. 6750 on the SW chip. Just kinda bumps it, kills either fuel or spark (or both) until the revs drop. I try to avoid it as much as possible.

I have on video the worst I've ever rode the limiter, at about 2:00:
https://youtu.be/wEcxRh83ekk?t=1m40s


...yeah I haven't done that since.

EDIT: After watching that I don't believe how poorly my car handled back then.

[GH85Carrera]

On a Carrera 3.2 the DME chip controls the rev limit. It can be deleted or moved up with a different chip but that would be stupid. The Carrera engine does not have great rod bolts. They can stretch and even break and destroy the engine. I would not push the rev limit on a stock engine more than a couple of hundred RPM and that is pointless to risk it.

There is no other limiter, just the DME chip. The SC is a different animal. It has no DME chip since it does not have a DME injection system.

I would call Steve Wong and order a chip with a stock rev limit in it. But that is just me.

[mgar88]

Anyone know if the SW Chips have rev limiters?

[Bill Verburg]

Originally Posted by Trakrat

hmmm... didn't think it would be smart enough to do that.
So does it completely lock up the injectors and starve the engine or is the fuel cut somewhere else..(fuel pump, etc....)??

Does this essentially kill the engine when it hits redline?

All cat equipped cars use a soft fuel cut off as the limit approaches, getting to a hard fuel cut off at the limit

This strategy protects the cats from meltdowns

[carreradpt]

Originally Posted by mgar88

Anyone know if the SW Chips have rev limiters?

Yes, they do. And you can choose your limit.

[s5uewf]

Actually, if memory serves you do not want to go over 6,000 rpm with stock rod bolts. You may want to do a search on it. I think the stock 3.2 came with small rod bolts that stretch and increase rod/bearing clearance, leading to engine failure. It's been a few years since I switched to a 930 from a 911, but I think that was the rap on the 3.2

[s5uewf]

I was off by a few hundred rpm, but you may still want to read:

Rev limit and rod bolts on 3,2

[Alex66]

Topic is also covered in Steve Wong's FAQs (scroll down):
911chips.com - Product Information

Brgds
Alex

[gtc]

Originally Posted by Trakrat

A rev limiter would have to be installed.... I don't believe these cars came with one. And a chip wouldn't be able to do anything, as the throttle isn't electronic.

Unfortunately you can't put a specific rpm value on what is considered bad and when valve float or other engine issues happen.

But for what it's worth... the red line is about 6750. Anything higher than say 7k, and you risk having your pistons kiss your valves.

How can someone who "spends time at redline," not know what the rev limiter feels like on a 3.2?

[ben parrish]

Be careful of advice that is so far off that its not funny....the cars have rev limiters. It will not save your engine from a mis shift but it will " bump" to remind you to shift. As Glen said above, It is not wise to fool with a much past stock limit on the factory rod bolts because of stretch but don't loose a lot of sleep over this ...because...there is a rev limiter built into the DME chip to remind you to shift if you are challenged in your attention to the screaming engine...like on a track.
Discussion is great but please be careful of Internet experts that speak with authority but have probably never opened an engine or even know where the DME chip is located.

[Driven97]

Play nice boys. If you want to see / hear the rev limiter in action see my video in post #9.

Try not to lean on the limiter often, but it's there if you need it.

[Tippy]

I used to have a Protomotive chip in my turbocharged 87. Don't think I ever hit the Rev limiter. Had to have been around 7k.

It was that way for years, and the stock rodbolts held fine with heavy Mahle turbo pistons.

These engines are not as fragile as you think with RPM.

Wondering if the ones who have had rod bolt failures only occurred during mechanical overrevs???

I spun mine to at least 8k, possibly closer to 9k RPM on stock rod bolts during my money shift and the stock rod bolts held for me, fortunately!