Ford Truck Enthusiasts Forums

Ford Truck Enthusiasts Forums (https://www.ford-trucks.com/forums/index.php)
-   1978 - 1996 Big Bronco (https://www.ford-trucks.com/forums/forum44/)
-   -   Anyone got torque curve graphs for 300 vs. 351? (https://www.ford-trucks.com/forums/1065254-anyone-got-torque-curve-graphs-for-300-vs-351-a.html)

ErrorS 05-08-2011 02:29 AM

Anyone got torque curve graphs for 300 vs. 351?
 
I'm never gonna be able to do a diesel swap, i'd love to, it's just not gonna happen.. 351 to 300 i6 might be a reasonable swap to consider though. Everyone says the 300 is a torquey beast, that's all I want.

Does anyone have torque/hp graphs comparing the two engines? I suspect the 300 has more lowend, many people here swear by it and absolutely love it.

mako5972 05-08-2011 07:18 PM

Why not just use an aftermarket 4x4 cam from Comp Cams or an rv cam? I think that would be a lot better than an engine swap to the inline 6. I drove both the inline 6 and a 351W. I prefer the 351W, that is just my opinion.

greystreak92 05-08-2011 11:17 PM

There is a good reason the 300 was dubbed the "poor man's diesel" a very long time ago. Consider the fact that it develops its peak torque and HP between 300 and 500 RPM LOWER than a typical V8. Afraid i can't help with graphs but the numbers speak for themselves.

If you are used to the kind of throttle response you get from a car or a big V8 then making the move to a 300 is going to take some adjustment because it just isn't that kind of engine and face it, if you were considering a diesel swap, it would have the same shortcomings. The "umph" is there (and a lot sooner than with a V8) but its not in the form of break-neck thrust... just steady strong pull... gee like a TRUCK!

85e150 05-08-2011 11:24 PM

If you want MORE torque than the 351w, or torque at a lower rpm, the 300 is not the answer.

More at about the same revs with the 351w.

Engine_Specifications

ErrorS 05-08-2011 11:52 PM

That sort of makes me think I'll get that lowend torque I'm looking for, 260ft lbs at 2000rpms is insane for a 6. Is the 351w putting out 260ft lbs under 2500rpms? I just want a relatively flat curve, the 351w feels more like a potential race motor.

I loved the 400 in my 78, been chasing that kind of power for a long time. That motor had nothing behind it on paper, but when being used it was a beast. I don't care about that torque boost you get at 2500RPMs or so with the 351, I can feel it well, I know the power is there but it doesn't get moving quick enough.
honestly, I just don't like the 351. I get no torque at lowend, a kick in the butt at around 2500RPMs, then it goes flat at about 3500RPMs, it's tough keeping it in its power band with an auto offroad, really tough. I dunno, I just don't like the way it feels under my foot, I guess it's tough to explain.
Then with bigger tires keeping at speed in overdrive or 3rd is a pain with this motor, it just doesn't feel like it was built for what I'm using it for. I have to drop it to second to get it up to speed on the highway, which everyone knows isn't fun finding gears with an auto.
Regear isn't an option until I finalize my tire/suspension setup, which might take a while.

The motor is going out, it's the next thing to be replaced.. been wanting to do a diesel swap since I got my first Bronco a few years ago, it never happened. The time is coming to put a motor in my 90s and I want ot make sure I make the right move. Though, I'll PROBABLY just get my 351w rebuilt, I want to put some thought into a 300.

ErrorS 05-08-2011 11:55 PM

I wish gas was $2 a gallon again, I'd just drop in a 460 and never think about it again.. and I've searched and searched and searched, a diesel swap isn't an option, I don't have the money, time or location to do that kinda work (though I would absolutely LOVE to, if I ever hit a windfall, I'm paying someone to drop a Cummins in)

jdwoody 05-09-2011 12:36 PM

Well I have a 89 1 ton with a 460 c6 and 355s, a 94 3/4 ton with a 351 e4od and 355s, and a 95 bronco with a 302 e4od and 355s, they all have 35 in grips and are 4x4, the two small blocks might get one more mpg. And niether can keep up with the 460. Its by far my favorite ford engine period.

Kemicalburns 05-09-2011 01:19 PM

get desktopdyno and start messing around to see what the torque curves look like.

ManfredVonRichtofen 05-09-2011 08:41 PM

I have a 300I6/5spd in mine.

I towed my Ford 3000 tractor with implements on a 20'x7' trailer with no problems.

I just recently towed my 79 F150 4X4 with a 466/c6. I could tell I was being weighed down BUT I probably would pulled it better if I can fix my rear driveshaft and get off the front. :) LOL


I think with some mods to the 300, more weight for the Bronco with a good tow set up. The 300 can pull.

It's just going to cost $$$....just like with any other engine.


Check out Fordsix.com.

Them guys make some bad ass inline 6 engines for towing and racing.

ErrorS 05-10-2011 06:22 AM

There's also a huge weight and space issue with the 460s. I hate working on EFI engines as is, the 400 in my truck is physically bigger but LEAGUES easier to work on than my 351 because of the space. I can't imagine how bad an EFI 460 must be in a lifted Bronco.

Was never really a fan of the 460 carbed motors, I really think the 400 is my favorite truck motor Ford has ever built though, and I never compared it to a Windsor, just to the 300 and 460. I'd kill for an EFI 400... well, if gas was cheap again. I honestly think a carbed 4 bbl 400 would use more gas than a carbed 460.

I need to find a good EFI 460 to drive around to see if I like how it feels. It produces power at around the same times the 351Ws do if I'm not mistaken, just more of it.

and thanks on the reminder about desktopdyne Kemical, forgot it even existed!

ErrorS 05-10-2011 06:41 AM

desktop dyno lies, it's showing like 375ft lbs at 3000RPMs and 350ftlbs at 2000. If its showing me gross HP, fine, but i know for a fact there's a lot more than 25ft lbs of torque difference from 2000 to 3000, I can feel it kick in like I have a big turbo.

Is there mechanical problems that would cause what I'm talking about? Everything is free flowing, but even if it wasn't I'd think that would hurt me more up top. Few people share my complaints about the 351w, but I always just assumed they didn't have much to compare to.

I use to have a better dyno app, I spent good money on it but for the life of me can't remember where i put it, or even what it's called so I can go download it.

jas88 05-10-2011 08:35 AM

Here are the graphs you asked for. This is from a 1990 F-Series brochure:

http://jastrauss.fastmail.fm/1990_p16.jpg

ErrorS 05-10-2011 11:33 AM

Wow, those graphs are perfect. I especially love how I was right on with the 351, it feels exactly like it looks in the picture. Strong as heck from 2000-3000RPMs but only there, annoyingly weak at lowend and highend. It is sooo tough to keep it in these RPM ranges with my current gearing and tires.

The 300 is sweet but it really doesn't match the 351w at any RPMs. I'd probably like the way it feels more. I really need to drive an EFI of around the same year.

Was looking on eBay and I can get a 351 longblock with cam for about $1600. I thought it would be a tad cheaper, but that's still do-able. I hate that my cam options are so limited, gonna do some research and see if I can't built it a tad better for towing. I don't mind losing 50-75hp at the topend if I gain 25-40ft lbs of torque at the lowend, not trying to compare dyno slips with anyone. Should also really help gas mileage..

460s weren't options on these trucks were they? Just on the big vans and 1-tons? I forget which year they stopped offering them, I know it's rare to see a 460 efi in a junkyard.

hey, and thanks. You got the rest of that brochure? that's pretty awesome.

85e150 05-10-2011 03:05 PM

Read the graph again. The scales are different engine to engine.

The 351w on that graph shows 260 lb-ft at 1000 rpms. The same as the 300 at it's peak. And 290 when it signs off, again more than the other engines peaks.

Keep in mind that's a 1990 chart. What year is your 351w?

ManfredVonRichtofen 05-10-2011 05:47 PM

460S stop production in 1996, from what I remember. Mostly in F250-F350s and maybe some vans.


All times are GMT -5. The time now is 05:54 PM.


© 2024 MH Sub I, LLC dba Internet Brands