[84broncorig]

i am getting a hold of a 77 highboy with D60s front and rear. I was told it is a 390, i just seen a pic of a 351M and it looks like this engine. this engine in this truck has edlebrock cam, carb, crank, intake, air cleaner. where on the block can i find the numbers and where can i go to find out what the numbers mean??

 

[F1rocco]

You can count the valve cover bolts........Also on the 390 the Casting numbers is between the second and third spark plug...Should be like D5te or on the 460 the casting is on the head as well similar spot.......For the 390 the numbers on the block are behind the starter...

 

[bmc69]

A highboy would have originally had the 360 or 390...360 in '77. The valve covers on the 360/390 FE engines cover the head AND part of the intake manifold. The thermostat is in the intake as well...on the 351m/400 the thermostat is in the block and the 7-bolt valve covers cover only the head casting itself..like 'most' engines. Are you sure it is not a lowboy that somebody simply lifted? Big differences between the two types. The lowboys came with 351m or 400 engines and the tcase was bolted to the tranny, not divorced like it is with the highboys.

 

[84broncorig]

did lowboys come with D60s front and rear?? I checked that out. I did look at the tranny and transfer case...it is bolted to each other and it was made 7 or 77 and i kno they did change half way in to the year to a low boy. but when they changed it to a low boy did they change the front clip to square head lights and full grill or keep the 73 to 77 half grill and circle lights?? is there a way to tell from the vin number if the truck is a lowboy?? i just don't want to get my hopes up and think it is a high boy with a 390 all worked up and find out it is just a 351 or 400 modified worked up.

 

[bmc69]

neither lowboys or highboys came 'most' with 60 fronts. The highboys had the closed-knuckle HD 44..the lowboys the open-knuckle HPD44. All highboys had round headlights..period. Lowboys went square in '78.

 

[bmc69]

Don't get confused by the old '77 1/2' thing..that was NOT a real transition point..plenty of '76 round-eye F-250 lowboys around with the 351m/400 and mated tranny/t-case..wide-frame, etc. I have one here in my 'collection'* (in fact, the title on that one says '75 but somebody did make a mistake somewhere on that score)

*collection: a kind term for the assemblage of many,many piles of truck remains on my property. Syn: junkyard:thumbup

 

[84broncorig]

so what you are telling me is since i have the round lights and split grill then it is for sure a high boy???

 

[84broncorig]

ok i was just lookin on summitracing.com and noticed on the edlebrock performer intakes, it is stamped on there, 390, 400, 351 and so on....i am gonna look on it tomorrow to see if it just tells me....but just from lookin at those ones it looks like a 390.....thanx for all your help....i can't wait to get this truck in the mud!!!

 

[bmc69]

so what you are telling me is since i have the round lights and split grill then it is for sure a high boy???

No..read my post again. What I meant was if it was a highboy it would have to be a roundey/split grill, but lowboys were too in 76 and early 77.

If you are going to seriously wheel the truck, having 60s on both ends and the non-divorced t-case setup is better anyway. I love the highboys and the FE engines but their particular flavor of D44 front was not much to work with...

 

[84broncorig]

well i looked on the edlebrock intake and on the back it says 400 so its not a 390 like i was hoping....and it isnt a divorced tranny and transfer case so it is a low boy witha lift but it does for sure have D60's with 4.10s locked.....well atleast it is a 400M and not a 351M....i can be sorta glad about that....woulda been nice to be able to have the braggin rights of a 390FE...o well maybe next truck....thanks for ya'lls help!!!

 

[bmc69]

well i looked on the edlebrock intake and on the back it says 400 so its not a 390 like i was hoping....and it isnt a divorced tranny and transfer case so it is a low boy witha lift but it does for sure have D60's with 4.10s locked.....well atleast it is a 400M and not a 351M....i can be sorta glad about that....woulda been nice to be able to have the braggin rights of a 390FE...o well maybe next truck....thanks for ya'lls help!!!

Sounds like a great rig to me. But..uh..hate to bust yr bubble on the engine. ALL 351m/400 4V intakes say '400' on them. The only way to tell for sure if yours is a 351m or a 400 is to measure the stroke. 3.5" = 351m, 4.0" = 400. (just '400'..not '400m', BTW:toothless )

 

[84broncorig]

i just took it for a drive....whatever it haves it has lots of power...so i will just tell ppl its a 400 lol!!

 

[bmc69]

That works. Prolly true too, since a 351m isn't going to result in any 'woohoos' from pushing on the skinny pedal. But I have lots of 400 rigs that will...:thumbup .