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I know this has been covered in depth but I’m having a hard time pinning down where my EGR and Vac advance need to be routed from what I’m reading on here. I want to simplify my routing to help sort out some pinging issues.
I no longer need to have the emissions equipment on my truck as it will be registered as an antique here in VA. Truck is a 77 F150 4x4 400/C6. It was originally a CA emissions truck. Engine is stock with edelbrock cam, straight up timing, and performer 400 EGR manifold. All emissions equipment is there, but Cats have been removed. I have an edelbrock 1906 ready to go on but I am waiting for a new dizzy first. In the meantime. I plan to remove the charcoal canister, vac amplifier etc. Is it correct to route the EGR valve to the carbs spark port and the Vac advance to manifold vacuum? Or should I use the ported vacuum switch on the T-stat housing? Also planning on removing the thermactor pump at the same time.
I know this has been covered in depth but I’m having a hard time pinning down where my EGR and Vac advance need to be routed from what I’m reading on here. I want to simplify my routing to help sort out some pinging issues.
I no longer need to have the emissions equipment on my truck as it will be registered as an antique here in VA. Truck is a 77 F150 4x4 400/C6. It was originally a CA emissions truck. Engine is stock with edelbrock cam, straight up timing, and performer 400 EGR manifold. All emissions equipment is there, but Cats have been removed. I have an edelbrock 1906 ready to go on but I am waiting for a new dizzy first. In the meantime. I plan to remove the charcoal canister, vac amplifier etc. Is it correct to route the EGR valve to the carbs spark port and the Vac advance to manifold vacuum? Or should I use the ported vacuum switch on the T-stat housing? Also planning on removing the thermactor pump at the same time.
thanks in advance.
EGR valve would go to the E port (emissions port) on the carb. Not all carbs have this port and typically only emissions carbs will have it.
In my opinion, if you don't need the emissions equipment, why would you put the EGR back on? It's not needed and won't help anything at all.
I've been on pause on working on my 78 Bronco due to the fact I'm in Kalifornia and it has to have the emissions crap on it, I wish I could do away with all of it on my 77 F150 4x4, my 77 F250 4x4 and my Bronco, the numerous times I've had to smog my 77 F150, it runs super clean w/o the EGR.. (I had it bypassed just to see) it passed just fine. If you don't need it, put it in a box, label it in case you ever need it, put it on a shelf and fuhgetabout it
Should be listed in the literature included with the carb.
Or post pics of the carb...
Also if you do not need the EGR for state inspections I would dump it, it has the most negative impact on power and economy of all the emissions systems.
The EVAP (Charcol can)is the last thing I would dump as it has no impact on fuel economy and engine power.
My understanding is if you dispose of the EGR system without an adjustableVac advance and a richer carb you will experience some ping. Since I’m already getting a lot of ignition ping I would like to get to a baseline before removing the carb and distributer. The old “don’t fix two things at once”.
My understanding is if you dispose of the EGR system without an adjustableVac advance and a richer carb you will experience some ping. Since I’m already getting a lot of ignition ping I would like to get to a baseline before removing the carb and distributer. The old “don’t fix two things at once”.
The ping is more a result of modern fuels. Being a Cali calibrated truck it was already on the ragged edge of lean throw in today's fuels and it will be running on the lean side and ping is the result of that.
On the fuels available when the truck was built losing the EGR would not typically result in pinging. The ignition curve vac advance will not make a difference especially in a Cali calibrated vehicle where the ignition curves were very conservative to start with.
Regardless of what you do the fuel-air should be richened up. Pull the EGR and richen up the fuel-air mix to operate without the EGR. Ignition curve can then be readjusted and it will not affect the fuel air mix. You can't do anything with the ignition curve till the fuel-air ratio is corrected anyway. Fuel air, then ignition.
Thanks for the advice. Sounds like it’s time to stop chasing the ping with my current setup and go ahead with the carb install. Then see what I end up with.
Ditch the EGR, install carb and tune accordingly, most vacuum advances have a small allenhead inside to adjust if you are getting too much advance, did this on my 77, took allen wrench with me, drove, turned and drove some more till no ping.. I believe you want as much advance as you can w/o ping.. takes a little tweaking. My 77 "accidentally" ahem.. got tagged as a 73, so I am in the process of finishing up putting the 351Measly back in with no smog crap, Weiand intake, 500cfm Summit carb, HEI dist, comp cam. We'll see how this all works together, anything is better than what it was, it was always a bit Measly, but even more so than my 77 SB 4wd.
Let us know how it works for you!
Ditch the EGR, install carb and tune accordingly, most vacuum advances have a small allenhead inside to adjust if you are getting too much advance, did this on my 77, took allen wrench with me, drove, turned and drove some more till no ping.. I believe you want as much advance as you can w/o ping.. takes a little tweaking. My 77 "accidentally" ahem.. got tagged as a 73, so I am in the process of finishing up putting the 351Measly back in with no smog crap, Weiand intake, 500cfm Summit carb, HEI dist, comp cam. We'll see how this all works together, anything is better than what it was, it was always a bit Measly, but even more so than my 77 SB 4wd.
Let us know how it works for you!
good to hear.
I spent a good deal of time, and money, rebuilding the OEM emissions set up using NOS parts off eBay and vintage parts warehouses three years ago. Got the truck together just in time to move out of state. Now, three years later, I’ve shipped her out and have time to do the tuning I never got to do. Glad I get to remove the emissions stuff, but will be keeping and labeling all of it in case I ever move back.
Just to be clear the vac advance only comes in to play during cruise conditions and is the last thing you adjust. Fuel air mix then total timing then vac advance
EGR shall always go on he PVS themo vacuum switch because you dont want EGR to operate until the engine is up to temp. But you should just cap off the EGR and not worry about using it at all.
would be great if we had a nice pictorial of a stock engine. each vac line and how it is routed in a nice color photo portfolio.
LOL
my truck is far from proper hoses. so i cant take proper pics. some day if i find the right truck i would take tons of pics and create a good vac hose thread.