I've been reading this since I'm also running a P-S 1000HP on my 414 that was originally on my 517B. Mine isa 3 circuit primary plate and the small block needed just a slight amount of tuning to idle. It's a "typical cold natured Chrysler Product" as one of my old mentors used to always say, once it warms up it seems fine. I think I'm at 88/6.5 and 94/plugged F/R, I've wondered would there be any major benefit to plugging the primary and square jetting (since I'm Foot-braking at 3000 off the 2-step so I'm really just launching off the Back shooters anyway). I'm thinking since the PV is vacuum/load sensitive just square jetting it might be more consistent and may actually make a little more torque. Thoughts?

BTW... I have nothing but High praise for Patrick, I gave him my BB 517 to SB 414 parameter changes and he told me where to jet.

IMO, you can't have clean hot and cold idle without a choke. Cold engines like to be rich (choke on) until they warm up (choke off). I have the hot idle on my 950HP nice and clean and just deal with it being cantankerous when cold.

Idle gets better when warmed up but it is still too rich at idle when warmed up. Shoot I gotta go look at the air bleeds, be right back.

My jets are 84 front and 92 rear with #76 idle air bleeds and Hi speeds are #32

Here's how mine idles, bout as good as it gets for what it is, I reckon

https://www.youtube.com/watch?v=Fnv3UJB6xxk

Have you checked the throttle blade yet to see how much transfer slot is showing? You may be able to lean it out with IAB and mixture screws. If not you'll need to change the IFR's which will also change the cruise afrs.

The money I spent on my LM2 was well worth it.

I haven't yet, I will check it either tonight or saturday as I'm still finishing up on the interior right now and want to get it done before saturday afternoon.

I'm looking at the MTX wideband set-up

I have not had good luck dealing with him. Both of my carbs were way off, and I found him tough to deal with. This is why I decided to try a G3 Holly on my latest purchase. I will be getting that on the dyno soon, and I will take my SV1 with me, but it will be the G3 that wins I will bet....




Scrap the #76 idle bleeds and switch to #70's.......That is for chevy calibrations as they idle a lot leaner. Mopars need fuel at idle.

Me, I would remove the power valve and square it right up with 92's or 93's and then work the HS bleeds down a little towards #28's and see. Maybe go a #31 or #30 to start with after you have made a couple of runs squaring it up. Mine was much more responsive that way.

The 76 idle bleed is cos of a rich mixture and a 32 hi bleed is too big.

Got a suggestion where to start with the air bleeds?

Idle is too rich now, but I like the block off power valve in the front and run 94 square idea.

What size ifrs and how much t slot showin

Can somebody respond to my question of the benefits of square jetting/blocking the PV in terms of throttle response/consistency for a 3000 rpm/stutter 2-step launch on a 5000 stall converter. Am I likely to see any real difference (60' et improvement) since I'm essentially shooting off the rear pump shot anyway? I mean it seems logical to me (take the potential PV "flutter" out of the equation and truly equalize the A/F ratio from F/R) but want to get my head around the real reasoning or something I'm not considering. I know it's easy enough to try but before I do I want to hear other opinions....thanks!

The 1000HP 4150 carb was originally on a 508" street driven Big block where the PV was beneficial for cruising.

As I stated, I got a stronger signal and instantly better idle and throttle response, almost like it had a small vacuum leak, but I never found one and yet I checked many times. I do not trust the PV delivers fuel evenly with a nasty cam. With a street car, its probably a lot better, but when you have real duration and a real lack of vacuum signal I think its best to get rid of it. I have the best idle on this thing and yet my duration at 50 is over 300......

I run this carb on my 512 and the jetting and air bleeds posted above flat out works. I trap 110-111mph in the 1/8th with this thing. The way he sent it did not. And it took a while to sort it out, but its about as good as I think it will get and I want to focus on the SV1 a little.

i had the same problem with my engine when it was cold, it took a few minutes of foot assisted idle to keep it running til it was able to run by itself. one day i used a higher grade fuel. instantly it ran like a regular streeter. no foot assisted idle, could select a gear without it stalling, the engine ran real nice even in our winter, (no snow). my suggestion, use a better grade fuel.

Put #70's in for the idle air bleeds....start at 1 turn out on the idle screws.

I finally had a chance tonight after working on everyone elses car to mess with my R/T. I pulled off the carb and not touching anything from where I have had it. the transition slots have .020"-.030" showing on the primary and secondary throttle plates.

What is the IFRS?

It does this on my shell V-power 93 or VP 110 race gas, so it isn't a fuel issue.

Since I also do street driving would blocking the front PV be a bad idea for me?

Removing the pv on a street driver will cause over fuelling at lower rpm and cruise rpm . Some like to set dyno af ratio then fit pv and jet down some . I have thought to change air bleeds but never got there - slackarsed i guess . I am happy to accept a larger cam ,big carb and single plane will often lead to a rough low idle when dead cold .

Tex