The 1962 service manual talks about the H carb idle adjustment
on page 37 of section 14 "Fuel System".
I recently worked through a bit of a head scratcher trying to tune the Carter 3258/3259 carbs on my H using the FSM…the diagrams didn’t even show the air bypass screw let alone describe how to tune it/them…am I missing something or is this another instance of FSMs falling short (were they an afterthought)?--
BTW, I can attest to Carl’s’ skill on tuning the short ram J…once I get past cold start after sitting for a while, it runs beautifully. Great throttle response and pulls like Big Boy No. 4014. Thanks Carl!
Kurt
--On Thursday, September 17, 2026 at 7:37:49 AM UTC-5 jkg wrote:
This is an old subject but years have gone by and those interested in this , some pretty smart guys have gotten in pretty deep ..... I have " tuned " a lot of rams over the years and surprised by variability in final outcome . Despite a lot of effort, some cars kind of fight, you a few settle in.
This is not about obvious stuff we all know , it is about things rams do at times. Maybe all times , more or less . And some on site have really gained significant knowledge over past 20-30 years
I have one fighting me now , the constant fight between stable rpm at idle and slamming into gear and then stalling. As if idle has no torque if " loaded up" They even mention this " rough engaging" in user guide on F .
Part of it is due to unported vacuum to ignition , always full advance at idle . If vacuum drops ,at trans engage, ( it does) ignition retards = stall . I mean this is real and anti stall thing grew out of it, but opening throttle more just off idle drops vacuum more . Thin line there . And I think design is flat out wrong we have to tune around it .. I was thinking ??? add a small vacuum can and orifice to slow down advance action , or buy carbs with ported vacuum like every single other car the world has . Carl did that his car runs great . AVS calls to me ..
The second thing is the tendency to stall off a stop sign depending how much you feather pedal .
It feels like it goes lean momentarily ( remember this is some cars not all)
So seems like carb squirt is either late to the party with small thrittle motion startup off idle , not enough gas , or idle mixture wants to be richer than optimal ( as set by vacuum gauge) to cover this transition It us really bad puling into traffic and car suddenly stalls, adds stress to driving . This is tangled around issue 1
I am ignoring warm up issues , another whole thing , but gets into this in first 15 minutes
Lets call it ole ram guys , philosophy etc .
Can be made to be acceptable , yes, but really optimal -- no, not easy to get to . And how about ignition timing ? they say "no spec for that idle timing with vacuum on , just set with off" .but it IS on st idle . And high , ? leading to above sensitivity to stalling slamming all that
Deep thinkers on this , insights gained welcome ..
J
For archives go to http://www.forwardlook.net/300-archive/search.htm#querylang
---
You received this message because you are subscribed to the Google Groups "Chrysler 300 Club International" group.
To unsubscribe from this group and stop receiving emails from it, send an email to chrysler-300-club-international+unsubscribe@xxxxxxxxxxxxxxxx.
To view this discussion visit https://groups.google.com/d/msgid/chrysler-300-club-international/a7d3e4aa-8f24-44dd-9222-314294490fc5n%40googlegroups.com.
Back to the Home of the Forward Look Network
Archive Sitemap