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TonkaToy
08-05-2010, 09:18 PM
I have a 73 with a stock F engine, 58k miles, complete with smog pump and gear. My goal is to get the most out of that little engine possible, without cracking it open.
To that end, would I gain anything by removing the smog stuff? Is there anything I need to know about doing so?
Also, is there any benefit to changing over the stock air filter set up to some sort of CAI?
And finally, any other suggestions to get this thing to be all it can be would be appreciated.

Short of being a little short on power, it runs and starts great right now. Keeping it that way is important to me!

Air Randy
08-05-2010, 09:36 PM
Does it have the oil filter on the driver's side or passenger side? If it's on the passenger side it's a 1.5F, which means it's the same cubic inches as an F motor but has the new style 2F oiling system. They only made the 1.5F during 73-74.

Removing your smog stuff isn't going to have much impact on performance. Make sure it is tuned well, the carb is jetted correctly for this altitude and your timing is advanced beyond the stock setting. For this altitude you want to run as much advance on the timing you can get before it starts pinging or dieseling. That will probably make it a little perkier.

You can take the exhaust manifold off and install an after market header and exhaust to let it breath a little better but that will only give you a 5-8 HP increase. Unless you want to mill the head to increase the compression and install a performance cam there isn't a whole lot more you can do to these things.

subzali
08-05-2010, 10:32 PM
make sure you know where your engine stands healthwise before messing with stuff; do a compression test and make sure everything is working up to snuff, and as Randy said, advance the timing a few degrees to give it a little more perk. Then see where you're at, those are the simple things. I desmogged my 2F and, besides removing a poorly operating smog pump, didn't really notice any difference.

Hulk
08-06-2010, 11:21 AM
How much smog stuff does a '73 have, anyway?

SteveH
08-06-2010, 01:58 PM
The only really nasty emission control on mid-70s LCs, IMO, was the vacuum retard function, which retarded the spark just when you needed it advanced. Once this is disconnected, and the timing is advanced slightly over stock, you're 95% there with any power gains. I doubt the '73 had a vac. retard distributor. I would disturb as few things as possible, should emission testing ever ramp up and get nasty in Colorado.

Rzeppa
08-07-2010, 09:50 PM
How much smog stuff does a '73 have, anyway?

Not much worth noting as far as power-robbing stuff. No EGR, no AI system, etc. Prolly the worst offender will be if it has a retard dist.

TonkaToy
08-07-2010, 10:14 PM
Thanks for the advice everyone. I did pick up a new header today at the rally and talked to Randy some more about the timing issue. I think I will start saving for that electronic ignition and send the carb into his carb guru for a little help. As far as the smog stuff, my only thought was the parasitic drag from the actual pump itself, which I understand is pretty nominal.

PabloCruise
08-09-2010, 01:23 PM
If Randy's carb guru is Jim Chenoweth, then I would read up on his posts on MUD.

Search FJ40Jim and read up on his recomendations of what systems to keep vs. ditch.

I think it will corelate highly with what has already been spoken here.

Air Randy
08-09-2010, 01:28 PM
If Randy's carb guru is Jim Chenoweth, then I would read up on his posts on MUD.

Search FJ40Jim and read up on his recomendations of what systems to keep vs. ditch.

I think it will corelate highly with what has already been spoken here.

It is JimC:bowdown: