3.4 swap into 1985 Jeep Cherokee questions?

[geoffinbc]

In line pumps suffer from vapor lock and are less efficient, more noisy and run hot and never last as long as an in tank pump.

[cardana24]

Also, now that I am going with the SFI set up what am I going to need to use from my old 2.8 engine? Would I still need to swap the oil pan/pick up? I am guessing I can just run the serp. belt now instead of the V belts. What am I missing?

[cardana24]

It is much more efficient to push fuel than to pull it. Less chance of collapsing your fuel lines with the tank in the pump, considering the great increase in pressure you'll be dealing with.

I'll see what I can dig up. I'm guessing a 4.0 inline 6 would be a good place to look since they make more power than the 3.4

[Canyonero]

It is much more efficient to push fuel than to pull it. Less chance of collapsing your fuel lines with the tank in the pump, considering the great increase in pressure you'll be dealing with.

[cardana24]

I will try to pick up a 5 speed ecm. The harness I have will work with this correct?

Why do you suggest the intank pump so strongly over the inline? I am just curious because swaping fuel tanks was not something I was planning on.

Oh, and I picked up a VATS system bypass on ebay. With shipping and insurance it was not even 30 bucks so that sounded a lot better than wiring a bunch or resistors.

[Canyonero]

With my Trooper SFI swap, I just nabbed a fuel pump and pickup assembly from 4 cyl Trooper (the 4 cyl used multiport). Dropped right in and worked great, one of the few things in my project that did. Might see if you can do something similar, grab a newer Jeep's fuel pump assembly.

[geoffinbc]

Yea your going to have to find a chip from a manual trans car. If you want to use the SFI system I STRONGLY recommend an in tank pump. Use any Jeep pump that was used on the 4 or 6 cyl SFI engines. They will supply the fuel you need. Like I said if you can get the tank with sending unit from the junkyard then do that. Then all you need is the return line and off you go.

[cardana24]

Any parts store will have it. You can just run a few PSI. 25 PSI will do it. Just remember to leave your compressor on because they cylinders do leak down so the compressor will need to be able to recharge.

on all of the air hold valves I found they want a pressure of 90-125 psi. I ordered one from summit yesterday. Now if my valve springs and retainers would ever come in I can move along with this project. I have decided to take a shot at running this on the SFI system since I have so many of the parts needed already. I am going to order a VATS bypass, and I will need to get a different fuel pump. I am assuming I can just use the stock Fuel pressure regulator that is still mounted to the rail, I will just need to run a return line. Any advice on fuel pump or anything else envolved in running the SFI system? Also the ECM that I have is from an auto, but I have a five speed...will this make a difference? Does the ECM even have any connections that go to the tranny?

[cardana24]

Assuming I am going to run this set up with the stock SFI system from the Camaro, i will need to bypass the VATS system. Does anyone know if this product will work? For the price it looks like it could save me a lot of time.

http://www.wirelesshut.com/0/10929678.html

[geoffinbc]

Any parts store will have it. You can just run a few PSI. 25 PSI will do it. Just remember to leave your compressor on because they cylinders do leak down so the compressor will need to be able to recharge.

[cardana24]

Yes the tool is the one that screws into the plug hole. The other end attaches to a compressor.

do you know where you can buy it locally rather than getting it online? I assume when you buy it the tool will tell you how much pressure you should be running to it?

[geoffinbc]

Yes the tool is the one that screws into the plug hole. The other end attaches to a compressor.

[cardana24]

Nah I would just leave the heads on. Unless you think you should inspect the pistons and cylinders. The pressurization tool for the cylinders is cheep and convenient makes quick work of spring changes.

Which tool is the right one? I looked at the links the were posted and one of them just looks like a little thing that screws into the spark plug holes...is that the right one?

I have a video of the engine running and not smoking or anything so I do not have any reason to believe that something in the bottom end of the engine is bad.

I did not get a chance to work on anything today but here is a pic of how I left it yesterday. I got dampner off then the timing chain cover, and I took the exhaust off, then the most time consuming part was scraping all of the old gasket material off of the timing chain cover area and the valve cover gaskets. Does everything still look fine?

[geoffinbc]

Nah I would just leave the heads on. Unless you think you should inspect the pistons and cylinders. The pressurization tool for the cylinders is cheep and convenient makes quick work of spring changes.

[cardana24]

Looks normal. A little more rust than I like to see in the water passages. But some heavy coolant flushes over the first few month should take care of it. No need for harsh cleaners or anything.

yeah that's what I was thinking, there is a lot of rust in the coolant passages.

Would my cam/lifter/valve spring replacement be easier with the heads off? Would I still have to worry about droping valves? I am thinking if I can get the exhaust manifolds off it really is not much more work to change the head gaskets. Any thoughts on this?