2.9 to 2.8 swap

offroadohio · Post by **offroadohio** » Sat Feb 12, 2005 2:55 pm

What will it take as far as wiring to convert a 2.9L bII, to run a 2.8 with stock 2.8 ignition? Computer swap, and a couple wire changes?

broncoo · Post by **broncoo** » Sat Feb 12, 2005 3:34 pm

can i ask why you would want to do that the 2.8L is kinda a dog

swapping a 4.0L would be just as easy

offroadohio · Post by **offroadohio** » Sat Feb 12, 2005 3:52 pm

Well, if you find me a 4.0 for $30 and everything needed to put it in, ill do that. But, the point of putting the 2.8 in (which ive ahd WAY better luck with than ANY 2.9) is, I dont have the money to spend on rebuilding a 2.9 or buying a good running one. I have the 2.8 that runs great which I picke dup for $30 minus the carb... I have a spare carb I pulled from one in a junkyard, so thats no biggy. I just need to knwo what needs changed as far as wiring goes. I know ill have to regulate the fuel, or remove the pump from the tank, and etc...

broncoo · Post by **broncoo** » Sat Feb 12, 2005 4:31 pm

i can't say what you're gonna need then i was just goin on the fact that i toasted 2 2.8's

btw i have a carb for a 2.8L with only 3000miles on it from brand new sell it to ya for $50cdnobo

ranger5.0 · Post by **ranger5.0** » Sat Feb 12, 2005 5:25 pm

You will need the 2.8 engine harness and ECM. Depending on what year it is it should plug right into the body harness. I found that removing it all and running a Mallory Unilite distributor cleaned up the engine compartment.

Also you will remove the rev limiter with the dist. The carb will work without being hooked up to the computer. Though I used the carb off of a 77' crapi. I will agree that I like the 2.8L better to. It is a little more maintenace due to the solid lifter cam but it was way more fun to run especially at 7000 rpm

.good luck I attached a picture of the 2.8 with the Duraspark II ignition. It work well but it failed over time and still had a few wires involvedas you can see.

Post by **Nobody** » Sat Feb 12, 2005 5:46 pm

ewwwww 2.8L

I understand doing what you got to do, but giving up fuel injection would be a hard thing for me to do. The 2.8L valve train WAS nothing but problems for me.

As for the actual conversion......I guess you just need the engine, engine harness, computer, and regulate the fuel pressure. Of course if you don't hook up all the emissions crap, your gas milage is going to suck.

offroadohio · Post by **offroadohio** » Sun Feb 13, 2005 12:45 am

Nothing is hooked up in my 85, and i get over 20mpg on the highway, only gettin 25 in my 2.3 efi.

Ive never had any valve troubles in my 2.8 nothing but opil pressure troubles in ALL the 9's ive had.

This bronco is forsale and it has oil pressure problems, ive diagnosis it down to cam bearing. I certainly dont have the time nor money to mess with a rebuild, and I cant seem to get $300 for it anyplace. So, its time to spend as little moeny as possible to get it running, no inspections in ohio so emissions wont be a bother. I dont have a 2.8 harness but im pretty sure my buddy has one I can take, at no cost.

ranger5.0 · Post by **ranger5.0** » Sun Feb 13, 2005 9:37 am

Adjust the valves every 12,000 miles or once a year what ever comes first for a worry free top end. I noticed a vibration set in whenever it was due. .0014 Int-.0016 Ext. Never a vavle cover leak.

(P.S.) A mallory Dist. is only a couple a hundred bucks and then you won't have to worry about finding the ECM and wiring. Way easier to install and noticable power gains!!!! 2 wires

DBrown · Post by **DBrown** » Tue Feb 15, 2005 11:15 am

I really had no problems out of the 2.8 in the 84 I used to own. the big differences I noticed was between the two trucks were the tranny and the gears. the 84 was an auto(C5) with 3.45's(I think) and the 86 was a manual with 3.73's. so they felt totaly different. I can tell you this after a friend at toolies total engin air flow played with the 2.8 at the shop and we got it back together it was a lot stouter then the 2.9. I sold the truck to a friend that abused it daily and it was still kicken untill he let it overheat.

IMO both suck.....the only one that has an advantage is the 2.9 because of EFI. I would do the swap just for the simple fact it can give you some more time to figure out which direction you want to go if you keep the truck.

the one thing you could look at is when you swap over to carb the 302 swap could be easier to initaly get going because the ease of wiring.

offroadohio · Post by **offroadohio** » Tue Feb 15, 2005 1:24 pm

No need for thi snow...t rucks gone... EBAY RULES....

well, it sold on auction, now to see fi payment arrives.

Rockcrawler · Post by **Rockcrawler** » Tue Feb 15, 2005 1:44 pm

do you still smog the truck? That engion will never pass! Here in CA you cant put a motor in thats older then the truck.

offroadohio · Post by **offroadohio** » Tue Feb 15, 2005 2:42 pm

This isnt cali, this is ohio.... lol no smog regulations

DBrown · Post by **DBrown** » Wed Feb 16, 2005 8:08 am

KY has no smog either. they actualy shut it down in louisville after it had been up and running for years.

Rockcrawler · Post by **Rockcrawler** » Thu Feb 17, 2005 5:21 pm

well then i have to say is that i hate you

thats cool well then you should have no problems with the law then.

offroadohio · Post by **offroadohio** » Thu Feb 17, 2005 8:02 pm

BTW.... you got ym vote for TTC..... :)