170 CID straight six weak?

[famvburg]

I've got my dad's '69 with this installed & in 1st & 2nd gear it seems fine, but throw it into 3rd & it just seems weak. I've just gotten it driveable & haven't driven it much, but pulling some fairly long hills, I have to go back to 2nd & it doesn't seem to get much over 50 MPH on the highway. We had a '72 or '73 way back, (new), with a 302 CID V-8 & I learned to drive in it as well as drove it afterwards until we sold it & I don't recall it being a slouch, but in the early '80s, I had an old IH Scout with their 4 cyl (maybe 150 or so CID?) & it wasn't a speed demon by any means, so maybe I'm expecting too much from the 6. I haven't really checked anything yet, I wanted to drive it some. So, folks, am I just expecting too much from the 6? It has a little 1 bbl carb on it, if that info helps.

 

[mwood44]

If it doesn't smoke and the compression is good it's probablly giving you its best. I6s are usually quite drivable if geared correctly. in fact looking at the specks for the 66-77 EBs the 170 I6s had about the same power as the 76/77 302s The smog crap they put on the late 70s 302s really killed the power some where around 122hp on a 77 302. and 105hp on a 67 170. I wouldn,t mind having one of the old 6ers myself but I would for sure run 4.11s or lower.

Mike

Palmer Ak.

 

[S_bolt19]

The I6 isn't going to be a speed demon by anymeans. It is an extremely reliable engine and will do what you ask of it within the limits of that particular engine. If you are looking to have an engine with over the top horse power then you need to get a bigger V8. I wouldn't change out the I6 for a couple of reasons. #1 it sounds like you really don't need much other than a good tune up #2 if it is geared correct, it will keep up with most anything in crawling & #3 it isn't a gas hog like the 289 or 302 is.

 

[Yardape]

Your six is definately no powerhouse, just give it a good tune up, get a new carb or have someone rebuild yours and thats prett much all you can do. Well aside from mods but thats a whole new thread

 

[trains11tjc]

The I6 isn't going to be a speed demon by anymeans. It is an extremely reliable engine and will do what you ask of it within the limits of that particular engine. If you are looking to have an engine with over the top horse power then you need to get a bigger V8. I wouldn't change out the I6 for a couple of reasons. #1 it sounds like you really don't need much other than a good tune up #2 if it is geared correct, it will keep up with most anything in crawling & #3 it isn't a gas hog like the 289 or 302 is.

No arguements or anything but as far as gas being better than a 289 not so sure about that if you're gonna be crawling. not enough engine to move 33 inch tires so the engine will be trying to push them and using more gas whereas a 302 or 289 would'nt be straining because its got the power to push it those tires so it wont be using as much gas.... not much of a difference in gas usage but just a thought. i have a 66 with a I6 and it slow too. its got the granny gears like yours and 3rd gear is extremely low. it sucks when you want to get up and go somewhere. but a tune up really does help when i first got mine ran ok but i went and got a tune up and it made a major difference in how it drove.

 

[S_bolt19]

.... not enough engine to move 33 inch tires so the engine will be trying to push them and using more gas whereas a 302 or 289 would'nt be straining because its got the power to push it those tires so it wont be using as much gas....

That is where gearing comes into play. If you gear it correctly, you can accomplish anything. In my EB I used to have 3.50 gears, add that to the freshly rebuilt fuel injected 302 & I had more power than my Uncle's EB that was still carbed & 4.11 geared. He was still out climbing me because he was geared lower. I swapped out to an NP435 trans then did a regear to 4.11s & I double his crawling ratio because I have a lower geared transmission. Rock crawling is all about gearing. You can have the biggest, baddest engine on the planet, but unless the drivetrain is geared appropriately, you won't do anything that a correctly geared rig with a moderately built engine will do.

 

[bronco6banger]

Here is the new head for the 170/200/250 I6 http://classicinlines.com/ http://fordsix.com/

 

[famvburg]

I think I accidentally figured it out. Vacuum leak(s). When I changed out the vac wipers for electric, (see another post a while back), & removed and/or plugged off the respective lines & connections, the thing turned in to a whole different vehicle! While it still doen't do more than 60ish, it's way better than it was. Noticably more power for sure. My suspicion is that since the vac wipers barely worked anyway, the vac motors probably were leaking, even tho I couldn't hear any leaks.

Here is the new head for the 170/200/250 I6 http://classicinlines.com/ http://fordsix.com/

 

[SAYBYE]

I've got a 67 with the 170 six. I had a surge/hesitation at cruse I put new points in with cap,rotor,plugs,wires, new fuel filter. Still had the surge.Tried to get a rebuild carb, after getting 2 sent that were bad. ( I never even put them on linkage bent, plate couldn't open all the way) I tryed a rebuild kit. Still had the problem. Then the condeser went only a 1000 miles on the tune up. I got a pretronix electronic ignition from Bronco graveyard. It solved the probem it now has more power, starts easyer,runs all around better.

 

[stepchild]

I to have a 69 w/ a 170 in it and have experienced the same issues. I'm currently have 4.56's and 33's and still have to down shift on a good hill. I'm in the process of upgrading my carb, these engines are really restrictive as far as breathing goes w/ the built in log manifold. I'm upgading to a carter yf carb off a 240-6 motor, maybe something to look into, or you could start collecting parts for a turbo setup, like myself.