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Apache'71 · 03-06-2018, 06:38 PM

Thought I'd add an update for anybody following or who may be thinking of doing this to a rig requiring CARB compliance.

I got everything installed about two weeks ago and it fired up on the first try! It ran great (despite me plumbing the fuel pressure regulator backwards)! I re-plumbed the regulator, revisited all the MSD settings and can't believe how well it's running. It fires up nearly instantly, it idles pretty well (better than before but I think I could further improve it if I was controlling timing), and the throttle response is almost like a new, ok maybe newer, rig. I could never break the rear tires loose before but now I have to be careful to keep from doing it. There must be at least a 20hp increase on the bottom and mid end.

I have a more noticeable knocking sound (valves?) at low rpms in 2nd gear under load and a slight backfire when coasting in gear when cold and warm, but these issues were present before the Atomic install. The engine probably has some bad valve guides (blue smoke on startup) and could probably use a valve adjustment I suppose. Maybe the vacuum advance on the distributor is defective too. All things to run down in time...

The factory air injection system is still installed on the rig and to the best of my knowledge is functional, but it doesn't seem to be throwing off the O2 sensor as MSD told me it would. Probably the only thing that could pose a problem for emission re-inspection is the fact that the old carb had a TRC actuator mounted to it and there is no provision or way to remount it to the MSD to my knowledge. I just left the vacuum valve that's mounted on the manifold there and capped off the vacuum line since there is no actuator anyways. I guess I'll cross that bridge in two years when it's up for re-inspection...

The only things left to do is to remove, cap off or just ignore the old hard fuel line along the frame rail, remove the mechanical fuel pump and blank off and figure out why my fuel gauge isn't working now after installing the new sending unit.

Hopefully this will give some other folks on the fence a little more piece of mind where CARB compliance needs to be maintained.

Let me know if anyone wants more details on parts used, install, MSD settings, etc.

03-06-2018, 06:38 PM	#28
Apache'71 Registered User Join Date: Jul 2006 Location: Clayton, CA Posts: 37	Re: MSD Atomic EFI on '79 K30 in Cali Thought I'd add an update for anybody following or who may be thinking of doing this to a rig requiring CARB compliance. I got everything installed about two weeks ago and it fired up on the first try! It ran great (despite me plumbing the fuel pressure regulator backwards)! I re-plumbed the regulator, revisited all the MSD settings and can't believe how well it's running. It fires up nearly instantly, it idles pretty well (better than before but I think I could further improve it if I was controlling timing), and the throttle response is almost like a new, ok maybe newer, rig. I could never break the rear tires loose before but now I have to be careful to keep from doing it. There must be at least a 20hp increase on the bottom and mid end. I have a more noticeable knocking sound (valves?) at low rpms in 2nd gear under load and a slight backfire when coasting in gear when cold and warm, but these issues were present before the Atomic install. The engine probably has some bad valve guides (blue smoke on startup) and could probably use a valve adjustment I suppose. Maybe the vacuum advance on the distributor is defective too. All things to run down in time... The factory air injection system is still installed on the rig and to the best of my knowledge is functional, but it doesn't seem to be throwing off the O2 sensor as MSD told me it would. Probably the only thing that could pose a problem for emission re-inspection is the fact that the old carb had a TRC actuator mounted to it and there is no provision or way to remount it to the MSD to my knowledge. I just left the vacuum valve that's mounted on the manifold there and capped off the vacuum line since there is no actuator anyways. I guess I'll cross that bridge in two years when it's up for re-inspection... The only things left to do is to remove, cap off or just ignore the old hard fuel line along the frame rail, remove the mechanical fuel pump and blank off and figure out why my fuel gauge isn't working now after installing the new sending unit. Hopefully this will give some other folks on the fence a little more piece of mind where CARB compliance needs to be maintained. Let me know if anyone wants more details on parts used, install, MSD settings, etc. __________________ '79 Chevy K30 LB '71 Chevy K10 LB Avatar '71 Chevy C10 LB, 350cu, 6" Lift, 35" Tires (Photo taken in 1996 after first restoration) Last edited by Apache'71; 03-06-2018 at 08:33 PM.