What's a good idle RPM?

65coupei6

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I got the FiTech installed and running. I set my idle to 950rpm. This is with a Schneider 264-74H cam with 110 lobe and C4. My vacuum is pretty low. Around 12-13 at idle.

It seems to like the 950. Should I go higher or lower.

A big thanks to Gus. He sent me his FiTech file which got me started. I think he had his set at 850 or 900 with a stick, no C4.
 
With that much overlap and a 110 lsa you are probably in the ballpark. Is that in park? That's why with an auto ppl prefer a 112 lobe angle to give a better idle in drive at a stand still. Are you running a higher stall converter? You might need one to make it behave in drive at a stop. Stock idle spec is 525-650 in drive so you're not too far off. You're never going to get to that with your setup, but you find it's happy place within reason. If it's really struggling once it's in gear w/ the brake on or it's really pulling in gear stopped you may need a looser converter. The good news is with efi you've got complete control of it or you should at least. I've read some complaints about fitech not releasing the software to let you do more than their apple style idiot proof setup and ecosystem.
 
Thanks for the reply. I specifically asked for a 110. I liked the way my old cam idled.
My stall is stock. I have been putting off changing it.

I will play with the idle RPM a little and see how it goes.

The FiTech is pretty nice. Even with the entry version I have. There are a lot of settings as long as you turn on the Pro settings.
 
Take your curb idle up the 1000 rpms in neutral since you have a stock converter. Should have gone with a 112 L/C with a stock converter.
 
You'll find a sweet spot where it likes to live. I understand putting off the converter change. I've got a higher stall converter sitting in a box until I can justify getting to it :) I know I'm going to do it b/c I need to. I put a salvaged '87 v8 aod and it's converter in and it's *just borderline enough to bother me and affect the carb below 650. How's it doing otherwise? Like compared to running a carb off idle? I got mine from Oregon Performance Transmission but it's not installed yet. It looks like the C4 converters are a little more spendy.

Edit: it looks like they've all gone up since I bought mine a few months ago for $168 shipped.
 
I found a place that does custom converters for a little over $100. I just have to find the bookmark again.

The car runs way better than with the carb. Especially from a stop. I had the Holley tuned pretty good after the jet swap.

I still have to get a new exhaust installed. Going from 2" up to 2.5". (single out headers) This way I can also get my O2 sensor welded in.
I also want to see if the Widowmaker Muffler I bought sounds any good.
 
65coupei6":38loy9p6 said:
I found a place that does custom converters for a little over $100. I just have to find the bookmark again.

The car runs way better than with the carb. Especially from a stop. I had the Holley tuned pretty good after the jet swap.

I still have to get a new exhaust installed. Going from 2" up to 2.5". (single out headers) This way I can also get my O2 sensor welded in.
I also want to see if the Widowmaker Muffler I bought sounds any good.


If you find it, please pass along. Are they local to you only? Seems like a hell of a deal for ~$100. I’m going with a 110 L/C on my stock C4 as well, but have no power accessories to deal with.
 
Matthew68":3hbw0qmk said:
If you find it, please pass along. Are they local to you only? Seems like a heck of a deal for ~$100. I’m going with a 110 L/C on my stock C4 as well, but have no power accessories to deal with.

Here you go: http://gopnh.com/
 
That's a link to a file. I didn't download it and no else should either. Something wrong there with that link.
 
Link sez: Precision, New Hampton.
lists out a full function site for me.
Ck yer system, Seth?
 
Yeah it's working now. Last night it asked me to download a file. Maybe they got hacked or I clicked something wrong when I clicked on it.
 
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