Emissions Delete on a 1973 351C.

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Captain Morgan

Well-known member
Joined
Dec 31, 2015
Messages
63
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Location
SW Florida
My Car
1973 Ford Mustang Coupe. 351C 2V. Auto. All original, been in the family since new. Originally a California car, it's never seen snow.
Is it easy? I thought I remember a thread on how to accomplish this, but for the life of me I can’t find it. I would like to install an Edelbrock Performer 4 barrel/2V intake and I would love to delete the extraneous stuff. Thanks!

 
EGR is easy to delete but you also need to recurve your distributor. In 73, for emissions the ignition timing was retarded at idle. This hurts performance and makes the engine overheat at idle. There is a vacuum switch on the water pump that switches the ignition timing to manifold vacuum at idle when the engine overheats to cool it back down.

This is why I always run manifold vacuum advance and never ported advance. I never have any trouble with overheating at idle.

I am running 12-15 degrees advance at idle with the vacuum advance unplugged. It seems like its fuel dependent to what it likes. usually around 13.

I am running a duraspark distributor with 26 degrees centrifugal advance. I am using a GM HEI module to trigger it.

I have an adjustable vacuum advance diaphram and i plug the vacuum line back on and check the idle timing again and adjust that to about 15 degrees more advance than when unplugged.

Too little timing makes my exhaust hot, too much gives it a momentary hesitation when I increase throttle, I can't get the engine to knock anymore.

http://www.reincarnation-automotive.com/Duraspark_distributor_recurve_instructions_index.html

My best 0-60 is 5.65 seconds with a big hesitation in first gear due to too much vacuum advance, I cured that but haven't tested it again yet, should be around 5.2.

this is with a manual transmission.

 
Thank you for the info. I’m going to be tackling this soon and my other goal is a T-5 swap, so it sounds like deleting emissions and adding the Performer Intake and 4bbl will compliment that upgrade nicely.

 
I have a 73 H code with the Edelbrock performer and Holley. It has MSD ignition bored .050" over a mild cam and no overheating issues. I also has AC and automatic, I did add a Hayden transmission cooler. PO did the work I just bought it this way. The MSD is in the way of a stock air cleaner regular or Ram Air so have a small aftermarket.
I do run correct Cleveland 192 deg. thermostat also. When I got the car the PO had let it sit for 25 years in his garage in California which I thought was odd. So when it arrived I went through the brakes which were new but put new wheel cylinders, master and kits in the calipers. Pulled valve covers and it was all new so did not go any farther. So first time I drove it the temp went nearly to the H and when I shut it off it blew coolant out. I checked and he had put the Left Hand head gasket on backwards. So I pulled intake and heads and corrected and now no issues. This happens a lot the gaskets are clearly marked FRONT but people still put on backwards.

 
Modern Driveline helped me with my manual conversion. I would hesitate to put a T-5 behind a cleveland. Tremec has a new 5 speed out and it supposed to shift like a T56 but be smaller. I originally bought a kit from american powertrain and everything was wrong. Nothing fit. All I could use was the transmission and bellhousing. Modern Driveline saved me with a correct flywheel, clutch and clutch cable.

 
Thank you all for your wealth of knowledge! I’m excited to get this in running order. It’s been an uphill battle even though the car came from family in Southern California and was driven throughout it’s life. Nevertheless, as soon as I fix one thing, another goes. I feel like I’m playing whack-a-mole. 😂

 
Thank you all for your wealth of knowledge! I’m excited to get this in running order. It’s been an uphill battle even though the car came from family in Southern California and was driven throughout it’s life. Nevertheless, as soon as I fix one thing, another goes. I feel like I’m playing whack-a-mole. 😂
You'll get it in shape... concentrate on making it safe first. Once you get it "right" it'll be easy to maintain. 

 
I just purchased a T-5 I am gathering parts to hopefully build a track days car. There are many different versions of the T-5 so do your research as to which one to use. There were models for 4 cyl. & 6 cyl. that you do not want. Also the WC or World Class T-5 used in Cobras & GT and some others has better steel in the gears and the synchronizers are a composite that shifts much easier. I think I was lucky was on Facebook Marketplace and he had posted his add 20 min. before. He had just put new clutch in his 1995 GT mustang and went to drag strip to run. He put on slicks at track and ran no issues but he said he was tired and decided to drive short way home with the slicks on and hit water and crashed and totaled it. So I got the flywheel, which will not work on 351, new clutch, disc, throw out bearing, bell housing, transmission and a Hurst short throw shifter for $550 and he delivered it to me so I did not have to pickup with my screwed up neck. Here is pic of the tag this is said to be the best model for conversion to a 351C, 351 W, 302 W, 289 W.

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