493 stroker carb choice

[Shane Kelley]

Clearly not hearing the suggestion of looking at EFI....

The reason I haven't ventured that direction is a couple things. I have some buddies running them and we have chatted about it. The EFI doesn't have that snappy feel when it's down reving. Quick on open response but then a gradual drop in rpm's on the release. I like that instant "whap whap". The other thing is cam sensitivity with vacuum.

I haven't run one personally so maybe there are things that could be compensated. I'm just going by what I hear. I know new cars have the slow down rev also. So I really think that is EFI specific. But these things may not be a issue with everyone. 

[1 Wild R/T]

What your describing is the decell air bypass & it can be adjusted to act just like a carb....  And as far as cam sensitivity I have a buddy running a FiTech on his 512 with a cam that has 254 @ .050 duration.. It has no problem with the cam... Took some adjusting but thats to be expected... Personally my cam is 224/230 @ .050 & all I've done was plug in some basic info & fired the car up... It's been self tuning ever since.... Every time I drive it it just keeps improving... And considering it was better that the carb the first day......

[70Barracuda]

One reason I went Fitech, a fuel system was going to be near the same money.  You'll need a big pump and hoses running to and fro to do it right.  Is your tank up to that?  3/8 is small for 493.  Going lean will be bad news.

So nice to turn the key and it starts, no keeping it running, no messing around.  Lost a lot of wiring I don't need.   It does require a non Chrysler type ignition system.

On another topic,  The 493 is a mean, guttural sounding beast.  Im running Flomasrter 40's w tailpipes.  Its not to loud but step on the pedal just a bit and it sounds primal.  A sound Ive never heard before.
Love it!

[7212Mopar]

I am looking at the Fitech for my 416 stroker. Hoping to get better idle manner and cold start. I have the Comp cams XR292HR-10 242, 248 @ 0.05, 110 LSA and 106 ICL. The Fitech can also handle ignition timing. Has anyone install and use that feature? Does it mean the Mopar ECU and ballast resistor are bypassed and not use?

[70Barracuda]

To use Fitech you will have to eliminate all chrysler ignition.  You will use the blue and brown wires coming out of the bulkhead.  I am using a TSP ready to run distributor.  Not using timing control.  No boos or N2O, no need.

It does have excellent cold start, it runs pretty good, a  bit richer than I like and they say thats the way it is

[RUNCHARGER]

265 at 050. We had trouble with it at first but set it back to Fitech and it was good when it came back. MSD and Holley have good systems too. I will never buy a new carb again. Given the choice of changing jets, pump cams, pv's, bleeds I'll take the handheld anyday.

[7212Mopar]

  OMG 
That is a lot cubic inch and stroke to tame that cam
I am going  to download their diagram to study. I like the idea of changing ignition timing from the handheld input. But I will miss the RevNator.

[7212Mopar]

I like the idea of having Fitech control both fuel and ignition timing (plan to get the Go EFI 4 600 HP version). The unit is capable of changing ignition timing during cold start and running based on engine response. In reading through their wiring diagram, there is no more ballast resistor. I am wondering how the ignition coil is protected from seeing 12 volt during engine running condition. The way I understand is that Mopar uses the ballast resistor to lower voltage to the coil but allow 12 volt during cranking. I just email Fitech with the question. Will see what they say about this.

[1 Wild R/T]

Plenty of coils are rated for 12v all the time I've been using a Petronix 45111 without a ballast for 6-7 years...

[JS29]

Plenty of coils are rated for 12v all the time I've been using a Petronix 45111 without a ballast for 6-7 years...

The instructions that come with the coil will let you know.

[7212Mopar]

So I had been researching Fitech Mopar wiring the last few days. Looks like most of the info are on the A body and Charger forums. Info are scattered around and it seems that no one post wiring diagram for every application. There were some from folks that are running fuel only using the Fitech but could not fine anything on using Fitech for both fuel and timing control.

From what I gathered so far, looks like I will need
1. A MSD billet distributor with their phased rotor. The guy from Pace Performance kept telling people not to use the stock or stock replacement distributor as the signal is not strong enough. Currently I have the Firecore.
2. Locked the distributor and eliminate the mechanical advance. The distributor can then plug directly to the Fitech.
3. For the Fitech white wire, it can be connected to both of the blue and brown wires for constant 12 volt. Since the ballast resistor will be eliminated. I am thinking making a jumper wire to the brown and blue wire plugs off of the ballast resistor. The other side of the blue wire plug that has the blue jumper wire, I will run it to the positive terminal of the ignition coil. The Fitech black wire, light brown tachometer wire will go to the negative terminal of the ignition coil.
4. The tachometer plug, electronic ignition plug and positive coil wiring will need to be safe off and not used.

Did I get this right in terms of wiring? The other sensor wiring and fuel pump wiring seems straight forward. For the 12 volt main power, I am attaching it to the starter relay post.

BTW, it seems that a lot of people has RPM noise interference and were shielding the wires and run a ground strap from the Fitech housing to the engine. Anyone here have to do this?

[Chryco Psycho]

 
That wiring sounds about right / typical
The Firecore will likely work just fine assuming the curve is locked down

[7212Mopar]

I ordered the Fitech 600 HP with the FCC last night. There is a $100 mail in rebate from Fitech plus $50 off from Summit. It is backorder now and will not ship till at least Christmas. The system had been out three years and they still has not caught up in inventory. I wonder if they are doing made to order.

[303 Mopar]

I ordered the Fitech 600 HP with the FCC last night. There is a $100 mail in rebate from Fitech plus $50 off from Summit. It is backorder now and will not ship till at least Christmas. The system had been out three years and they still has not caught up in inventory. I wonder if they are doing made to order.

They are not made to order.  Several guys were experiencing issues with the FiTech set up and their customer service was severally lacking.  They could have slowed production to figure out the issues. However, most online supplies were having black Friday/cyber Monday sales so I think they just sold out of inventory.