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big six swap question

for a motor/trans combo for sale the other day and the person only wants 200 for everything. that said the motor is a 300 6 out of an 86 ford(f-series,van,bronco??) not sure on that but has 154k miles and i would like to pull the 300 out of my 79 and put this one in(79 engine runs on 5 cyls,leaks oil,and i think its headed south also has 30k miles more that the 86 motor) my question is would this be a direct plug and play deal since the engines are the same and the year of the vehicle and production are different or is this going to be more time consuming and expensive than what im thinking?? im goin to try to get the motor alone for 100 cash if its all plug and play. but if i have to pay 100 for the motor and then 300 in misc stuff to make it work properly and also im going to have to pay a friend to swap the motors too(not enough tools,time,and/or know how on that). then ill just say forget it and try to track down a cheap complete head to fix the running on 5 cyls or jus replace the busted valves. so 3 different options here but looking for the best. also the motor (one for sale that is) is complete with everything from what i saw in the pics minus the intake/exhaust manifolds and maybe the carb(all of which are obviously on mine :) lol) so any help or points into the general direction that i should head in is greatly appreciated. thanks in advance,bill
 
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I don't mess with the smaller stuff to much, but I am pretty sure they are the same. The only difference would be the motor mounts so I would check those closely. smilieFordlogo
 
the engine mounts are different between the model years. different part #s and you can tell by looking at them that they are 2 completely different styles. so will the 79 mounts work for an 86 motor??? the 86 mounts have a different bolt pattern and look to have a different setup for the rubber as well. but wouldnt they still sit in the same place on the engine and the frame?? and just the frame setup be different??
 

dustybumpers

don't play well w others
Basic block is the same.
Head is lean burn, but it will work fine.

The 85 will have a feed back carb, and a TFI distributor, which is driven by the computer'
The cure is to use the DS2 distributor and the carb off the 79. You will also want to use the emissions system off the 79. Basic swap though. I would do it for the $200
 

dustybumpers

don't play well w others
Oh, you will have to use the oil pan and pick up tube off the 79, sump is switched end for end between the 2 motors
 
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so basically i dont need to purchase any parts to make the swap work for my truck. use the same carb,dist,and swap out oil pans and pick up tubes between the engines and all will work properly??? im guessing this is what youre all saying. i figured i would buy the motor either way and worst case scenario swap the heads(this would be a quick fix on the engine running on 5 cyls) i cant even find a head from a junk yard for a pre 86 300. and most junk ayrds want between 100-150 just for the head. great news tho i contacted the person who has the engine and im goig to get the engine for 125 with out the trranny(no use for that its for a 4x4 and i have 2wd) but if ive misunderstood please let me kno. but thanks for all of the great advice :) bill
 

dustybumpers

don't play well w others
Nope that's all.
Some have had to slot the bolt holes in the early model carb a bit to work, but in your case, I would just change out the whole intake exhaust and be done!
You will probably notice a big change in engine response, the lean burn heads are pretty good. The only problem, they don't like to be overheated, and crack between the valves easier than the old heads.

As said before, I would buy it, and use it. You can't go wrong!
Set the other one that comes out in a corner, and build it High performance later down the line
 
"As said before, I would buy it, and use it. You can't go wrong!
Set the other one that comes out in a corner, and build it High performance later down the line". my thoughts exactly dusty bumpers :) build a nice mean v8 killin machine out of a bb6 definitely a plan there. i do have some plans for the original engine. was thinking at minimum a rebuild or maybe a rebuild with some slight modification like a port and polish headers and dual exhaust with a 4bbl intake. possibilities certainly end with the budget but that can always be a slow do some here and there process until its all finished. thanks again for all of the excellent advice. i really appreciate this alot. thanks guys :) bill
 

wizzard351

ride'n on 35's
2,145
120
wi
I took a 300 from a "90" model f150 4x4 and stuck it in my 71. all I did was swap engine mounts and the dist along with the carb and intake/exhaust manifolds, cost less then a 100bucks for parts
 

dustybumpers

don't play well w others
Midnight, Make sure to get some good help!



And you too can have one of these!

 
again thanks to everyone for all of their advice and input. i picked the motor up on thursday, currently its sitting in a wooden crate on top of a couple old tires in the bed of the truck. i do have another question now that i have the motor. the previous owner pulled it out of an 86 f-150 4x4 and left the clutch/flywheel assembly on the motor. will the clutch work with my 3/4 ton truck(i dont haul very much with it and when i do its usually less that 1/3 ton in the bed but usually stays empty) and i dont pull any trailers with it either. i did some digging and looked at the websites for a couple pf local parts stores and i saw that for 86 there were 2 different clutches for the 1/2ton 4x4s with the 4spd tranny. one is a 10" clutch disc and the other is an 11" clutch disc(standard for my 3/4 ton from what ive found) i dont really have the money to purchase a new clutch kit for the truck so be it 10" or 11" clutch will it work with my 4spd and only sacrifice towing/hauling abilities(which i can live with) or would a new clutch set have to be installed(i refuse to put the one i currently have installed with my truck on. reason being its temper mental at times. some times its really touchy and other times its "normal" and when i release the clutch there are times where the truck shakes and jumps around when you start to get it moving. i dont think the clutch i currently have is wearing properly or somethings outta whack. it doesnt slip or anything just more of an annoyance than anything. so can i run the 1/2 ton clutch thats already on the "new" motor in my truck or should i just bite the bullet and replace it?? i know that this would be the perfect time to replace the clutch since since the "new" motor is sitting in the bed of my truck but at the same time the sooner i get this thing installed the better with winter coming and nice days coming to an end not to mention a pretty tight budget. ive been bouncing back and forth with replacing the clutch and trying to run the 1/2ton clutch so i think i just need that final push to get my mind made up. and as always thanks again in advance for the helpful advice :) bill
 

Fellro

Moderator
Staff member
I put the 11" upgrade in mine, no mods necessary. Personally, I would rather just do the clutch and not have to take the trans back out in the near future. However, if it seems that the clutch disc has plenty of life left, and you can handle doing the job again in the future, then go ahead and reuse it. It also depends how much and what you use it for as to how much it will be an issue.
 

dustybumpers

don't play well w others
The other clutch is probably oil soaked, and that's why it acts up.

A decision really can't be made on the clutch on the new motor, until you pull it and inspect it. It may be worn out.
You may luck out, and it's a new 11".
 
so last week i finally "fixed" my truck. unfortunately the engine swap was a no go. the newer engine disty hole was just a tiny bit to small. the older dizzy wouldnt drop the last 1/4 inch into the new motor no matter what my friend and i did with it. fortunately for us his uncle told him to check that first before we tore everything apart and started the engine swap. so instead of a engine swap it was a head swap. exhaust valve on the old head has a 1/4 by1/4 chunk missing on the #1 cyl. bores all looked good except for #1 as well its scored up pretty good and when i fired the truck after the head swap was finished my friend listened to the engine as the oil pressure was building and said it sounds like its low its knocking. checked oil(full according to readout on the dip stick) and he said bottom end is getting weak and that i should run thicker oil in it to atleast keep the knocking at bay and it will have more oil pressure too. that is until i can have it rebuilt hopefully this summer. the day after the head swap was finished a guy in a nice 1ton dually was lookin for a parking space at my job and stopped and asked if that was a 300-6 in my bed and i said sure is he asked what i was doing with it and i told him as of yesterday its up forsale everything went with the motor except the air cleaner,valve cover,and head he asked for a price and i said give me 75 you can have it all intake,exhaust,carb,everything so thats been sold. truck now runs great and has lots more power and acts like its getting twice the gas milage. but thanks for all of you help with this its slow going but it is going :) so again thank you all for the insight and advise and help,bill
 

Fellro

Moderator
Staff member
Are you certain the hole is the issue, and not the oil pump drive? Darn things can be pretty tough to get to line up sometimes.
 
according to my friends uncle the "newer"holes are smaller than the older ones. we did measure just to make sure and there was a small difference(if i remember right1/8th inch difference between the two)
 

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