SBC Questions (1 Viewer)

[fumann]

Can anyone tell me which Rams Horn exhaust works best for an FJ40 SBC conversion? Casting numbers and pictures would be helpful.

Is anyone running a carburated SBC in a 77 or newer FJ40? Did you have to have air-rails and smog pump to pass metro emissions? I understand that the newer 67-72 Chevy Truck Rams Horns can be machined for air rails if needed.

Do I need to provide the smog equipment to match the engine or the year of the FJ40? I've heard it both ways. The donor Blazer is a 78 without smog pump, air-rails and with catalytic converters. The FJ40 has no catalytic converter and has smog pump and air-rails.

Thanks,

 

[inkpot]

Howdy! I am running a carburated SBC in a 76 FJ-55. Phoenix smog requires that the rig retain original type, or comprable, smog gear for the vehilce, not the engine. I used a 77 engine that came with cats, threw the cats away, and installed a working AIR system. I have retained the functional EGR and EVAP systems, also. In over 12 years of testing, I have never really had any problems. Only a few times has it even failed the initial test, and then it easily passed the retest after a minor tune up. I was told at the smog station that if I wanted to upgrade to cats in leiu of the smog pump, it would mean I would have to do my all annual testing at the referee station, since it was not "oroginal" smog equipment.

I would check your VIN to make sure you don't have a Kaliphornia issue truck, as they may require different smog goodies than the other 49. Just a rumor I heard once. John

 

[Cdaniel]

Here's a few previous threads on the subject........

https://forum.ih8mud.com/showthread.php?t=81765&highlight=emission
https://forum.ih8mud.com/showthread.php?t=119392&highlight=emission
https://forum.ih8mud.com/showthread.php?t=39674&highlight=emission

 

[fumann]

Thanks guys!

I read through all the threads and now it is as clear as mud. I called DEQ last week and the "technician" said if you put a later engine in it you will have to retain that engine's smog equipment. This position seems to be in direct contrast to the reality of what happens at the testing station, e.g. smog equip to match the vehicle/year. I trust what you guys are saying. Based on this, I'm going to lose the cats on the 350, and look for the rams heads machined for air rails and a Chevy smog pump.

I would like to get a good look at your engines at the next Sonic and maybe snap a few pictures if possible. I'm due for tags on the 40 this month, so I'll smog the 2F and then start the heart transplant right after that. I'm chasing down miscellaneous parts that I know I'll need right now.

Another question: Your thoughts on Marks or AA to Toyota 4 speed conversion?

Thanks,

 

[Cdaniel]

I read through all the threads and now it is as clear as mud. I called DEQ last week and the "technician" said if you put a later engine in it you will have to retain that engine's smog equipment. This position seems to be in direct contrast to the reality of what happens at the testing station, e.g. smog equip to match the vehicle/year. I trust what you guys are saying. Based on this, I'm going to lose the cats on the 350, and look for the rams heads machined for air rails and a Chevy smog pump.

I would like to get a good look at your engines at the next Sonic and maybe snap a few pictures if possible. I'm due for tags on the 40 this month, so I'll smog the 2F and then start the heart transplant right after that. I'm chasing down miscellaneous parts that I know I'll need right now.

Another question: Your thoughts on Marks or AA to Toyota 4 speed conversion?

Thanks,

Call again, see if you get the same answer twice from another expert.

Air rails are not necessary. As long as the air pump feeds into the exhaust some where in the line it will pass (both side if it's dual exhaust) Here's a pic of how mine looks. The big orange hose is feeding one side below the rams horn collector from the air pump.

If by chance you still have original paint and the sticker on the drivers door jamb, for 77there is a sticker there that says "non catalyst" for the ambitious inspector that won't believe what his computer says. Unless it's a CA spec of course.

 

[inkpot]

Howdy! True about the plumbing. I have seen it hooked up to the old oxygen sensor bung on a few rigs. I used the rail system because the doner car had everything on it, so I took the pump, brackets, manifolds, tubing, pulley, belt, nuts, bolts, spacers, etc. All I had to do was swap manifolds, loosen the alternator on the passenger side, hand to smog pump, and bolt it together. I'm running rear dump manifolds from an early 70"s El Camino. I ran the pipes down, behind the spring shackles, as I have a spring over and shackle reversal. John