GMC Motorhome 209 (fuel injection)

[@bradsnyder8802]

Should work. All the best!

[@ToniClark-n1g]

Fuel injection is definitely the way to go!

[@Mike_Classic_Cars-GMCMotorhome]

@@ToniClark-n1g agreed

[@bikertrash9318]

Hey Mike! Hope you had great Holidays and thanks for the video, I am still running carb but we do not take our coach into higher elevations and if it aint broke dont mess with it in my case. I need to update my build over on the forum and I am still doing the interior. Learning to build cabinets with hillbilly engineering!

[@Mike_Classic_Cars-GMCMotorhome]

Hope your Holidays were awesome too. I'm not happy with the current driveability. Hoping the FI makes a big improvement.

[@mudman7618]

Mike, good to see a new video. As we had talked at the June rally, my coach has the gm throttle body injection from a 90s 454. With my setup, I have the stock intake with the heat tube blocked off. Gm throttle body and stock air cleaner. All fits with no floor modification. Then I have a flex dryer hose off the snout of air cleaner to the Ragusa cold air scoop which is mounted in the slot of the grill to get outside air rather than hot air from engine bay. The only thing my system lacks is an intake air temp sensor which i plan to add for better fuel trim. For you, as the other mentioned I think the slope is due to cars having engine tilt for standard tail shaft transmission it compensates so carb is flat or level for floats. I think you could plane that off just above the runners, retaps the screw holes and seal them off. I don’t know how much that would affect performance if any due to shortening the length of intake. Probably negligible. If you’re dead set on the current do you have then I’d go that route. Unfortunately, I heard Bob R from dynamic efi passed away this summer. He was the guy who made the flashable board that replaced the factory chip in the gm ecm. I haven’t heard of anyone else worked there or is taking over. But if you weren’t set on using your current efi then I would suggest the gm one. With it I have knock sensor, electronic timing, etc. I think you mentioned yours doesn’t do timing? Also with the gm ecm, I found a newer electric cruise servo and with the speed sensor I’ll be able to have tap up/down cruise as well. But I have to replace coolant hoses before I do too much. Hope to see you at a rally this summer

[@do.it.better]

Looking forward to seeing this project to completion. I like many have opted FI system that replaces the carb. We also replaced the intake with the aluminum intake that Applied sells. It does look nice and works well.

[@Mike_Classic_Cars-GMCMotorhome]

@@do.it.better Thanks for the input, I do like a clean aluminum intake.

[@kukufoo]

Have you thought about modifying the engine cover instead? And then add a removable center storage/cupholder/console etc . on top of the hump. It seems like a wasted space there anyway for many things. Console could be attached to the cover with cleet and slam latch of some kind.

[@Mike_Classic_Cars-GMCMotorhome]

That's a good thought, I was hoping to keep that area flat for getting in and out of the cockpit

[@brucehislop8860]

I've been using a jeep snorkel on a GM Rochester throttle body since 2009. It was found by others that the barrel nearest the snorkel intake was getting starved for air. Using a spacer to raise the snorkel allowed the air to make the sharp 90 degree turn and solved the issue. Unfortunately I can't post a link to a photo on YT

[@Mike_Classic_Cars-GMCMotorhome]

@@brucehislop8860 Thanks Bruce, how tall is the spacer?

[@michaelmileski9830]

I'm planning fuel injection on mine too. I like the idea of a pony tank with the high pressure pump in it like most cars are built today. Being in the fuel keeps the pump cooler and knock down the noise. One thing I've seen is that you want to recirculate your fuel back to the tank. Have a port near the top of the pony tank that goes back to the tank and have the incoming port use a dip tube to put the new fuel to the bottom of the pony tank.

[@Mike_Classic_Cars-GMCMotorhome]

Thanks for the information I will have a tank return, I will have to see if a dip tube is possible with the tank I purchased.

[@michaelmileski9830]

I'm a machinist by trade for the last 40+ years. To me, it looks like you can take the whole thing down to the top the of runner castings. Just watch for interference with the new throttle body. Especially with the throttle lever. As far as the studs go, if those holes are at an angle, you can plunge mill them square to the new surface and put in a Heli-coil.

[@Mike_Classic_Cars-GMCMotorhome]

@@michaelmileski9830 thanks for the information I think I will do just that.

[@twschaar]

That's a nice Johnson you have there.

[@Mike_Classic_Cars-GMCMotorhome]

I hear that all the time

[@sjokomelk]

Just curious, but have you considered using a Holley Sniper EFI? They have a Quadrajet version that replaces the old carburetor one-to-one using the exisiting intake manifold, and you "only" need a new high pressure fuel pump.

[@Mike_Classic_Cars-GMCMotorhome]

I want to replace the cracked cast iron manifold.

[@twschaar]

I might be able to help design and 3d print a custom snorkel for you if you'd like. Get me some dimensions, and I'm happy to give it a shot.

[@Mike_Classic_Cars-GMCMotorhome]

Thanks for the offer, I will let you know after it is installed

[@michaelmileski9830]

Most cars have the engine tipped back which is why the carb is on an angle. In the end, the carb is level. Edit to add: Most rear wheel drive cars have the engine/trans at an angle in the car.

[@Mike_Classic_Cars-GMCMotorhome]

Makes sense

[@do.it.better]

Mike - You cannot own a GMC and be a cheap arse. GMC - get more cash for your GMC motorhome .

[@Mike_Classic_Cars-GMCMotorhome]

I've put over 25k in that thing but I'm still pinching pennies