What's the difference between 68-87 and 88-97 460 shortblocks?

[jade79]

I noticed Edelbrock lists the Perormer RPM kit to fit 1968 through 1987 460s. I sent them an email to see if the kit would work on a 88-97 shortblocks and they said the heads, intake and carb would, but I would have to try Comp or Crane cams for the cam. I'm not aware of the 460 using a roller cam, and I think those years were efi, but as far as the shortblock goes, did they use a different base circle cam or something??

[385seriesHemi]

I couldnt tell ya about the cam differences but I am sure Monsterbaby or Darrin1999 could tell ya. Sorry, I couldnt come up with anything myself. I think I should start studying more indepth on this so I know whats what in not just 460s. Good luck man

[Kurt.A]

The D9 and newer blocks have cyl walls that are .250 longer on the bottom end. Maybe they mean that the intake will not bolt to the stock FI heads. No roller cams in the 88 and newer that I know of.

Kurt

[Bear 45/70]

The EFI heads and intake are different from the earlier carb heads and intake and will not interchange except as a set.

[solidrunner]

I'm also wondering about this. I'm in the middle of a FI 460 build up and am having one hell of a time finding a timing set for it. I want a billet double roller, nothing too out of the ordinary and the guy at summit was acting like I wanted a replacement flux capacitor. He said that up to '87 is easy, but after that it gets complicated. I had Comp custom grind a cam for me, and that wasn't an issue. The summit guy said that I need to get my cam card and the casting numbers off of my block and call Comp to get the right timing set. This all seems a little silly, that's just me though.

[82F100SWB]

The EFI blocks are still D9 castings, I highly doubt there's any difference when it comes to the cam or timing set. As already said, the EFI heads/intakes are not interchangable, except as a set.
About the only difference in the shortblock is the dish in the pistons, the EFI's are smaller, but, that's about it.

[jade79]

I found a website on 460 block casting #'s which shows D9 as 79 "and later". I'm assuming "and later" means up to 97? 82F100SWB metioned efi blocks are also D9, which began in 88. So the same cam should fit 68 through the end of the D9 run. I'm just curious as to why Edelbrock lists the cam as 68-87. I was daydreaming of a potential project and using a newer shortblock since they're more plentiful in the local salvage yards.

[385seriesHemi]

Probably a different grind on them lobes. I cant really ponder too much else though. 1998 is the last year listed in my Fel-pro book. But I am assuming that was an option for '97 and 1998 and I think the last year was 1996 for mass production in of the 460s though.

[jade79]

I just got a reply back from Edelbrock. They state that the Perfomer RPM cam is a flat tappet cam and can be used in any 460 production block that came with a flat tappet cam, including 88 and newer. They list 87 as a cut off point because they say 88 and newer used a roller cam in some cases. Now I just need to figure what the casting number is for the roller blocks so I'll know which ones to avoid in the salvage yard.

[monsterbaby]

460s NEVER came from the factory with a roller cam, the reason that it is cut off at 87 is teh EFI ECU has a fit when you put things like a performer rpm cam in them. timing chains in 88 went back to straight up like the early ones but they are the same replacement chain all the way through the years (aftermarket quit making different chains in the performance double roller setups, only the factory stock still replacements make a diff on if they have the retard built in or not)
physically the short block is the same block, same crank and same rods and the cam cores are the same so you can physically put any cam into any of the blocks.

[solidrunner]

I finally called comp today and the guy said that any timing chain will work, set it for straight up and it will be fine. I might degree it in just to make sure, retarded cam timing sucks.

[aquartlow]

I believe that the early-late model timing sets will interchange, but the later model cam gear has no provisions for the fuel pump eccentric. I hope this helps.

[mudog715]

Originally Posted by jade79

I found a website on 460 block casting #'s which shows D9 as 79 "and later". I'm assuming "and later" means up to 97? 82F100SWB metioned efi blocks are also D9, which began in 88. So the same cam should fit 68 through the end of the D9 run. I'm just curious as to why Edelbrock lists the cam as 68-87. I was daydreaming of a potential project and using a newer shortblock since they're more plentiful in the local salvage yards.

I rebuilt my 1996 460 last year and it was a D9 block, so that confirms the block is the same 1979-up.

All 460 cams will physically fit in any 460 block. The issue with 1987-up 460s is most are speed density EFI which is intolerant of cam changes from stock. The only mass air SFI 460 was 1996-97 with CA/MA emissions. Those used an 80mm MAF, EEC-V processor and are OBD2-compliant. The mass air 460's ran MUCH better than the speed density 460s, even bone-stock. I noticed a substantial difference in throttle response, idle quality and usuable power just by switching from speed density to the stock 460 mass air system. It also seemed to gain about 1mpg in fuel economy after the change.

Some differences on external stuff:

-the water pumps interchange up to 1992-1993 when Ford introduced an oil-water oil cooler on 460's. it's plumbed into the lower radiator hose at the water pump and the water pump inlet size was reduced from 2" to 1.75" to match the cooler outlet. it is possible to make an early water pump work in this application but you have to make a custom short 60deg hose that's 2" on one end and 1.75" on the other (I can give you the part # if you need it). All 460 water pumps are 'standard rotation' -- they never used reverse rotation on a 460

- in 1996 the timing cover was revised to include a mounting boss for a crank position sensor (used on 1996-1997 mass air/obd2 460s as a misfire sensor). The 'F6' timing cover no longer has a fuel pump mount (previously they just had a block off plate on the efi motors)

- the stock timing chain on the EFI motors is straight up and on my 1996 at least, was double roller from the factory

- as stated many times before, the heads, intake & exhaust manifolds are unique to the efi 460's and must be used as a set. they will bolt on to a non-efi 460 so long as used as a set. there are two versions of the efi heads, E7 and F3, with the F3 having better stock flow characteristics and combustion chamber design.

- the last year for a "light duty" 460 was 1997 in F250/F350 trucks (old body style), but I think they were offered until 1998 in heavy duty (F450-up) trucks. I know that the 460 was still available in 1996 in E250/E350 vans, but I think the V10 replaced it either in 1997 or 1998.

[jade79]

Excellent info. Thanks everyone.

[scarless]

I want to convert my EFI to a carb setup. Is there an adapter plate that fits the EFI lower or am I stuck getting old heads? I haven't pulled the heads yet, is the difference square vs round ports?