3.4 swap into 1985 Jeep Cherokee questions?

[cardana24]

I will soon be swaping a 3.4 into my 85 XJ that has a carbed 2.8. For the swap I am going to stay with the carb, and I have a few questions so far. I know I will need to install an electric fuel pump, which pumps are recomended? I know I am supposed to get a low pressure pump for the carb. What about a fuel pressure regulator, do I need one, if so are there any that are prefered?

I am also planing on changing the clutch while I have the engine out. I sould be replacing the clutch with a 2.8 clutch and not a 3.4 clutch from a 93-95 camaro right? The most power it will ever need to hold is just from what ever power gains I can get from bolt on's.

I know the rear main seals are known for going on the 2.8 so I am going to replace the rear main seal on the 3.4 before I put it in. Are there other gaskets or seals that should be changed when doing the swap (I'm not rebuilding the motor)?

I also have a cam that I picked up off of ebay (I'll post specs later), but I have never replaced a cam before, but I have done engine swaps, I have just never changed major internal parts before. How easy is this when you have the timing cover off?

Are there any other worth while mods that will not break the bank that I can do while the engine is out of the Jeep? Thanks for any advice.

[geoffinbc]

Yes you need an electric pump. If you can get a tank from a later model Jeep that will bolt in and has the pump and pickup in it then get that. In tank pumps are MUCH better than inline pumps. The pump you choose does not matter at all. The regulator does. Just buy a low pressure carbureted bypass regulator. You do need a bypass regulator and you will need to install a return line. You cannot run a dead head system (returnless) or you will destroy the pump.

You need to select a clutch from a 2.8L S-10/Jeep Centerforce is the common choice.

The only reason the main seals on the old engines fail is because they are 2 piece. The newer 1 piece seals almost never leak but replace it anyway.

Cam's are easy, in most cases the bearings will still be within spec and you can slide out the old one and slide in the new one. You need to change all the lifters for new ones. They will come in the kit. Now is a good time to change the timing chain and sprockets. Aligning the cam is as simple as aligning 2 dots.

[cardana24]

Yes you need an electric pump. If you can get a tank from a later model Jeep that will bolt in and has the pump and pickup in it then get that. In tank pumps are MUCH better than inline pumps. The pump you choose does not matter at all. The regulator does. Just buy a low pressure carbureted bypass regulator. You do need a bypass regulator and you will need to install a return line. You cannot run a dead head system (returnless) or you will destroy the pump.

You need to select a clutch from a 2.8L S-10/Jeep Centerforce is the common choice.

The only reason the main seals on the old engines fail is because they are 2 piece. The newer 1 piece seals almost never leak but replace it anyway.

Cam's are easy, in most cases the bearings will still be within spec and you can slide out the old one and slide in the new one. You need to change all the lifters for new ones. They will come in the kit. Now is a good time to change the timing chain and sprockets. Aligning the cam is as simple as aligning 2 dots.

I am not going to change the gas tank so I am going to go with an in line pump. There were a few made by Mr. gasket at Advanced Auto. They were the same price but one was 1-4 psi and the other was 4-7 psi, which one would be better for my application? Where can I pick up one of the fuel pressure regulators you are talking about? The only ones I have ever delt with are adjustable and pretty expensive (i.e. AEM). As for making a return line is that pretty straight forward? Where does it go back into the tank? Is there already a common opening that is used or are you guys making one?

As for the clutch do I need something made by centerforce? I am trying to stay pretty low budget here without taking short cuts. I was thinking or running an OEM AC Delco clutch...is this a bad idea?

The cam that I bought did not come with lifters. Is there a good place to pick up some lifters or should I look around for another cam and lifter set? What is a good cam recomended for this engine? I am looking for more low to mid range power than anything. This engine should never really see high rpm's.

[cardana24]

Okay I found the specs on the cam I bought. Its made for a 2.8 Chevy V6. The grind is 256-H, valve lift is .42 for both exhaust and intake, the camlift on the intake and exhaust is .28 This is a Schneider racing cam and I would need to order lifters for it as well. Would I see a decent low to mid range gain with using this cam? I am not sure on the specs of the stock 3.4 cam.

[geoffinbc]

Get a summitracing regulator. They are affordable and work well. Get a pump that can handle 7 or more PSI and you should be fine. The return line can be plumbed into the sending unit. You may have to drill and install a bulkhead fitting. The tank may have to be dropped if the sending unit installs from the top. If possible you may be able to install an EFI sending unit with pump and keep your tank.

Centerforce clutches are reasonable just get the base model and don't spring for the dual friction. If you want even cheeper, Dynapack and others are available. OEM clutched are great too but I bet they are more than a standard Centerforce.

You MUST use new lifters. So pick up some Comp Cams or GM lifters. DO NOT buy any cheep lifters. They will screw you in the end. For the minimal difference in price save yourself a possible headache.

The cam you have sounds alright. I would keep it.

[cardana24]

Get a summitracing regulator. They are affordable and work well. Get a pump that can handle 7 or more PSI and you should be fine. The return line can be plumbed into the sending unit. You may have to drill and install a bulkhead fitting. The tank may have to be dropped if the sending unit installs from the top. If possible you may be able to install an EFI sending unit with pump and keep your tank.

Centerforce clutches are reasonable just get the base model and don't spring for the dual friction. If you want even cheeper, Dynapack and others are available. OEM clutched are great too but I bet they are more than a standard Centerforce.

You MUST use new lifters. So pick up some Comp Cams or GM lifters. DO NOT buy any cheep lifters. They will screw you in the end. For the minimal difference in price save yourself a possible headache.

The cam you have sounds alright. I would keep it.

thanks for your advice. I'll look into the stuff you suggested. As for the cam that I have where is that going to provide power? Will there be trade offs? Will it be worth the effort of putting it in (a decent power gain)? I bought the cam because i saw it on ebay and I picked it up cheap but I really don't know much about it. If this cam will be a good fit then I was going to contact the company that makes it about getting lifters.

Also which Fuel pressure regulator are you talking about from summit? The ones that I am seeing are all non return style. Which one are you refering to?

[geoffinbc]

Oh well I guess Summit doesn't have them. Well get the Aeromotive 13301 regulator. It does everything. I use it on my truck.

You do have another option. Some pumps can be used with a deadhead system because they have an internal bypass. But these pumps really heat up the fuel and the pressure fluctuates more. Not such a huge issue on a carb but it could become problematic. I would install a return system with any electric pump.

The cam will have great power around 2500RPM to 3500RPM and will have an operating range from 1000 to 5000 RPM. I do not know the IC of the cam so that may vary the power band up or down 500RPM or so. Not a big deal. The cam will be very streetable and will idle just fine. You will notice a nice gain over stock. The stock cams are pretty anemic. Throwing on some 1.6 roller rockers will get you even more torque. Call up the cam company and just ask if the lifters are good quality and if they have had any break in problems. They will probably recommend using Shell Rotella Diesel oil for break in. Also with this cam you will need new valve springs.

[cardana24]

Oh well I guess Summit doesn't have them. Well get the Aeromotive 13301 regulator. It does everything. I use it on my truck.

You do have another option. Some pumps can be used with a deadhead system because they have an internal bypass. But these pumps really heat up the fuel and the pressure fluctuates more. Not such a huge issue on a carb but it could become problematic. I would install a return system with any electric pump.

The cam will have great power around 2500RPM to 3500RPM and will have an operating range from 1000 to 5000 RPM. I do not know the IC of the cam so that may vary the power band up or down 500RPM or so. Not a big deal. The cam will be very streetable and will idle just fine. You will notice a nice gain over stock. The stock cams are pretty anemic. Throwing on some 1.6 roller rockers will get you even more torque. Call up the cam company and just ask if the lifters are good quality and if they have had any break in problems. They will probably recommend using Shell Rotella Diesel oil for break in. Also with this cam you will need new valve springs.

Do you know of any pumps that have internal bypasses that would be good for this? I'll check out the Aeromotive one you suggested.

As for the cam would it be best to just call the company that made the cam and order the lifters and valve springs? Here is a link to their site http://www.schneidercams.com/Camshafts.htm <<< that's what I am working with.

Also with the cam you are saying this one would be a good improvement over the stock 3.4 cam correct, you are not talking about the stock 2.8 cam?

[cardana24]

I have looked more at the fuel pressure regulators, and it seems that most of the ones that are desiginated for carburators are non return style so i am wondering why this would not work for me? If I get a low pressure pump and then set the adjustable FPR at the correct fuel pressure why would I need a return line? I'm asking because I don't know, i am not trying to start an argument. What is the correct fuel pressure for my carburator?

[geoffinbc]

Because an electric pump is positive displacement and will not slip, it will only stall. When you stall an electric motor you will burn it up. If an electric pump is designed with a relief valve it will allow fuel to bleed off when there is not a demand for it. However in most driving cases little fuel is required and the pump is pretty much bleeding off all the fuel it is pumping causing it (the fuel) to heat up. This is not so bad on a low pressure system and a pump with a low pressure relief. But with EFI pressures this would be a bad idea so that is why you don't see it.

The ones you see for carb applications are meant to be used with mechanical pumps and the electric pumps with internal bypass.

Your fuel pressure needs to be 4 to 7 PSI. When you get your carb it will recommend a pressure. If you use the stock one you need to check a manual.

I would just call the cam company and see what info you can get. Information never hurts. They should have springs for you. If not you can get Comps spring package or the GM Crate engine springs. The 2.8L and 3.4L cam are the same cam with different advance (Intake Center) ground in the cam. The cam you have will give you a healthy increase over both cams.

[cardana24]

I called the place where the cam is from and they want 140.00 for the lifters and 84.00 for the valve springs. I have never bought these items before but that seems high to me. Is this high? Is there are better place to pick them up?

[cardana24]

would these work just as well? How many do I need, 12? They are about half the price of the others. Where is another place to get valve springs? Also will this fuel pressure regular work well for my application? It's one of the cheaper ones I can find in my operating range that has a return line.

lifters

http://store.summitracing.com/partdetail.asp?part=EDL%2D41%2D1502&autoview=sku

fuel pressure regulator

http://cgi.ebay.com/ebaymotors/RACE-FUEL-PRESSURE-REGULATOR-3-PORT-CARB-4-9-PSI-909_W0QQitemZ230222391321QQcmdZViewItem?hash=item230222391321#ebayphotohosting

I went ahead and ordered my AC Delco clutch today. I found that kit for 120ish with free shipping and I got the fel pro engine gasket set too.

[geoffinbc]

Yea the Edelbrock lifters should do. Check the same place you bought your clutch from and see if they can get you GM/Delco lifters for cheaper.

That E-Bay regulator should do the trick too. But I have never herd anything about them so be cautious. See if anyone is selling an Aeromotive 13301 regulator.

[cardana24]

Yea the Edelbrock lifters should do. Check the same place you bought your clutch from and see if they can get you GM/Delco lifters for cheaper.

That E-Bay regulator should do the trick too. But I have never herd anything about them so be cautious. See if anyone is selling an Aeromotive 13301 regulator.

How about a place to get the valve springs, can these be stock or do I need aftermarket? I need 12 lifters correct? I'll keep an eye out for the FPR you use. Also it does not look like the place I got the clutch has lifters for the 2.8.

Oh, and I checked my manual, the fuel pressure going to my carb should be 6-7.5 psi, so I will make sure I get a pump and regulator that can handle that.

[cardana24]

I looked around more for fuel pressure regulators and i found the Mallory 4309 for 73 and some changed shipped thru Amazon. It is about 50 buck cheaper than the Aeromotive one and its not some off brand on ebay. I thought this would be a good alternative. here is the link if you want to check it out http://www.amazon.com/Mallory-4309-P.../dp/B000BWCE7E

I also went ahead and ordered a fuel pump from amazon as well since I was going to get the same one from advanced auto here in town, but with free shipping at amazon it was $10 cheaper.

http://www.amazon.com/Gasket-12S-Micro-Electric-Fuel/dp/B000BWCERY/ref=pd_bbs_sr_5?ie=UTF8&s=automotive&qid=1203659069&sr=8-5

it should do fine for what I need. its nothing crazy, I am just hoping it will be reliable.