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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

are the 351/400M motors any good?

  • Thread starter Thread starter blackstallion12
  • Start date Start date Jan 18, 2010
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blackstallion12

New Member
Dec 13, 2009
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Jan 18, 2010
#1
  • Jan 18, 2010
  • #1
i have axcess to a 400M motor for my 60 f100 and i was wondering if those motors make good power. i think they are pretty closely related to the cleveland. please give some input if you have had any experience with this motor or have heard anything about them.... thanks
 

EP429

Member
Jun 30, 2007
125
5
18
Central Texas
Jan 18, 2010
#2
  • Jan 18, 2010
  • #2
The 400 will require lots of time, work, and money to turn into a respectable street engine. You'd do better and cheaper to go with a windsor.

When properly built the 400 is a mean little SOB, but is larger and quite heavier than the 351C, uses a different transmission, and performance parts available are little to none. I'd pass
 

rbohm

Founding Member
Apr 12, 2002
6,698
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tucson,az
Jan 19, 2010
#3
  • Jan 19, 2010
  • #3
actually the 400 is a lot less expensive than people think. remember that you use the same cam as the 351c, the stock heads flow quite well out of the box, and with a little work they do even better. the only issue is the intake but edelbrock and weiand both make intakes for the 400. the 400 makes a nice street performance engine. as for the transmission, the 400 has the same bell housing bolt pattern as the 460, so any bell housing that fits the 429/460 fits the 400. if you want to run a manual trans, there are bell housings available, but a good C6 or even a lentech built AOD would be a better choice. pick your parts wisely and you too can build a 400 that makes better than 350hp on a budget.
 
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blackstallion12

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Dec 13, 2009
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Jan 19, 2010
#4
  • Jan 19, 2010
  • #4
thanks guys... yeah after posting i found an article where they made 500 horses and about 600 torque with this motor, but it sure wasnt easy. they used sbc rods and it think dodge pistons or somthing totall bastard build. yeah im not looking to build a race engine by any means i just need a torqy engine to pull around that HEAVY truck. i pulled a 390 out of the truck and that was just about the biggest mistake of you young life. but i have been looking into 351w 351c 390 or the big big blocks like 429/460s but we will see. i think im gonna steer clear of the 400 just because of part availability.

thank you guys for your input.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Jan 20, 2010
#5
  • Jan 20, 2010
  • #5
blackstallion12 said:
thanks guys... yeah after posting i found an article where they made 500 horses and about 600 torque with this motor, but it sure wasnt easy. they used sbc rods and it think dodge pistons or somthing totall bastard build. yeah im not looking to build a race engine by any means i just need a torqy engine to pull around that HEAVY truck. i pulled a 390 out of the truck and that was just about the biggest mistake of you young life. but i have been looking into 351w 351c 390 or the big big blocks like 429/460s but we will see. i think im gonna steer clear of the 400 just because of part availability.

thank you guys for your input.
Click to expand...

parts availability is just fine with a 400. i think the 400 build you saw was for a stroker motor in a 351w block. if you use the stock crank and rods, and a replacement trw piston, a little head work, and a decent cam, that 400 will make good horsepower and a lot of torque.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Jan 20, 2010
#6
  • Jan 20, 2010
  • #6
blackstallion12 said:
thanks guys... yeah after posting i found an article where they made 500 horses and about 600 torque with this motor, but it sure wasnt easy. they used sbc rods and it think dodge pistons or somthing totall bastard build. yeah im not looking to build a race engine by any means i just need a torqy engine to pull around that HEAVY truck. i pulled a 390 out of the truck and that was just about the biggest mistake of you young life. but i have been looking into 351w 351c 390 or the big big blocks like 429/460s but we will see. i think im gonna steer clear of the 400 just because of part availability.

thank you guys for your input.
Click to expand...

Keep the 400. All you need to do to it are these few things to wake it up: Replace the stock 2 bbl carb with a Holley 500 cfm 2 bbl. Swap the cam to a Summit Racing P/N 5200, add long tube headers and a good electronic ignition. I did this with one in a short bed 77 F100. Great all around combo. Lots of bottomend, good gas mileage.
 

Decurion

Member
Sep 28, 2006
353
0
16
Livonia, MI
Jan 21, 2010
#7
  • Jan 21, 2010
  • #7
Im with the other guys, 400 is not a bad motor at all. If youre rebuilding it, be sure to deck the block/heads as needed for quench and compression, though neither is absolutely necessary. Otherwise a stock rebuild with a good cam and intake is about all it takes to make reasonable power with one. One thing I will add is to get rid of the multi-groove valves if it has them. They are weak and allow the spring to move around on the valve and will cost quite a bit of top end power.
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Jan 22, 2010
#8
  • Jan 22, 2010
  • #8
Its a 400 cubic inch motor. So obviously, with some basic work, it'll move your truck just fine. If its in running condition as it sits, as others have pointed out, an intake/exhaust/cam could easily make it suitable power wise. But its heavy, needs a different transmission, will probably need new accessory stuff, and replacement parts are going to be more expensive.

However, unless you're getting the thing nearly free and in running condition (and also have access to an equally cheap transmission/bellhousing that is compatible), it'll be a bigger hassle than its worth compared to a 351w/c or a true BBF (either FE or 385).
 
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