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russell072009
08-04-2010, 10:42 AM
might need a motor soon, not too sure. can i use a 4.6 romeo short block from a sohc application? say an 04 vic. i would of course need to re use my heads, accessories ect. i would think that would work but i know ford all too well.

RacerX
08-04-2010, 10:56 AM
The main difference that would matter is the crank (6 or 8 bolt) and timing cover (use the original and you're all set). The mains and bearings are different, but, as long as all the internals are matched to the block, you can use your heads too. There's minor diff that won't matter so much if you get a short block.

Important to think of too: Are you staying N/A or plan on FI, etc. in the future???

musclemerc
08-04-2010, 11:22 AM
He's asking about using a SOHC block with DOHC components.

To answer your question No you can't

RR|Suki
08-04-2010, 11:25 AM
might need a motor soon, not too sure. can i use a 4.6 romeo short block from a sohc application? say an 04 vic. i would of course need to re use my heads, accessories ect. i would think that would work but i know ford all too well.

The main problem will be the shortblock internals, not the block itself. 2vs were low compression, didn't rev as hard etc. Shortblocks from actual 4v cars aren't too bad price wise


He's asking about using a SOHC block with DOHC components.

To answer your question No you can't

who told you that?

musclemerc
08-04-2010, 11:26 AM
So the block and the bottom end is exactly the same on all 4.6?

russell072009
08-04-2010, 11:35 AM
yeah i was worried about the compression. personally i'd rather eat 600 for a junk yard motor (2v) and rebuild it with my heads and accessories. 4v i'm looking at 3000+ just for the junk yard motor. i have no intention of going FI. would it work if i got the 4v crank, rods and pistons and just used the block itself from a 2v?

RR|Suki
08-04-2010, 11:37 AM
So the block and the bottom end is exactly the same on all 4.6?

depends on what you mean by bottom end. If you mean the rotating assembly, then you are talking about a shortblock, not just the block. The shortblock for the 2v is very different, they were lower compression, different materials etc.
There are also different blocks depending on where they were made (teskid(sp) for example) and what they are made out off (iron/alum). But as long as they are from the modular family you should be able to mix and match. That's why 5.4 heads work on the 4.6 etc. There have been lots of articles about putting 4v heads on a 2v, but seeing as you need just about everything else off of the 4v there's no reason to put the 4v heads on a shortblock with 8.5:1 compression and glass pistons.

RR|Suki
08-04-2010, 11:43 AM
yeah i was worried about the compression. personally i'd rather eat 600 for a junk yard motor (2v) and rebuild it with my heads and accessories. 4v i'm looking at 3000+ just for the junk yard motor. i have no intention of going FI. would it work if i got the 4v crank, rods and pistons and just used the block itself from a 2v?

Hmmm you can find marauder longblocks on craigslist for $1500, harness and all. But this is Michigan.

But yeah that's the way it should work, never tried it myself but the downfall has always seemed to be that you need everything off the 4v so it's a waste of money, not that the stuff won't bolt together.

but if you have a broken 4v you should be fine. . . but then again if you are going to get 4v internals to put into the 2v block, you also already have a 4v block. . . so why not just put the 4v stuff into the block you already have?

musclemerc
08-04-2010, 11:47 AM
You ask "who told me that". So I will ask you again, the question is: Can he use a shortblock from a SOHC and install DOHC components? I know the internals are not the same so why bother? Either way he won't have what he started with

russell072009
08-04-2010, 11:47 AM
minimize downtime. if i can have a short block ready to go that's less time i need to drive my truck while the car is down. at 25 bucks a day for fuel to run that beast it's worth the money to build another short block then yank the motor. as long as the heads are ok (they seem to be) it would only take a day to pull the motor, another to swap the parts over then a third to install the engine. last time i had a block rebuilt it took the shop about a week to get the block ready for me to assemble.

musclemerc
08-04-2010, 11:59 AM
Get a 4v shortblock. By the time you swap all the internals and add in the investment for a new rotating assy ~vs~ the hp/tq lost from a SOHC setup. Not worth it.

RR|Suki
08-04-2010, 12:01 PM
minimize downtime. if i can have a short block ready to go that's less time i need to drive my truck while the car is down. at 25 bucks a day for fuel to run that beast it's worth the money to build another short block then yank the motor. as long as the heads are ok (they seem to be) it would only take a day to pull the motor, another to swap the parts over then a third to install the engine. last time i had a block rebuilt it took the shop about a week to get the block ready for me to assemble.

ahhh, gotcha. I'm sure there are fast ford articles out there detailing everything you have to do. I'm not sure how searchable their site is, but it shouldn't be too hard to find.
The only cat I know who's done this had to mod the tensioners for the timing chains I believe. Other than that I can't remember any other big problems. You'd have a lot better luck on http://www.modularfords.com/
pretty sure one of the big NA power guys over there is running 4v heads on a GT block. You'd prob find a lot more people who've tried it over there. There are other mustang sites that would be good, I just don't know what they are. Modular Fords is the only one I go to.

russell072009
08-05-2010, 09:10 AM
well thanks for the input. lots to think about now. just in case i decide to do something foolish.... what's the weight difference between the aluminum and cast iron blocks?

RacerX
08-05-2010, 09:24 AM
about 80lbs. I just got one...

RR|Suki
08-05-2010, 09:26 AM
well thanks for the input. lots to think about now. just in case i decide to do something foolish.... what's the weight difference between the aluminum and cast iron blocks?

Ford Catalog I think makes it look like it's only 50lbs, but I personally think it's a typo, or they pack the two differently. I highly doubt our blocks are over 100lbs or I'm a lot stronger than I think, because they aren't hard to carry around. Seem like ~90 lbs. Mustang sites have guys who have weighed both I'm sure, I'd bet the difference is more like 80 or so lbs.

*edit* ^^^ beat me to it

russell072009
08-05-2010, 09:30 AM
so not enough that i would need to change front springs over. hmmmmmm

RacerX
08-05-2010, 09:31 AM
Al is 84lbs and the Fe is 160lbs.

Joe Walsh
08-05-2010, 09:33 AM
Our aluminum blocks are right at 80 lbs.

I loaded and unloaded a TEKSID block from my Marauder's trunk at the Ford Carlisle show...and my back is not what it used to be.
If it was 100+ lbs I would, errr.....my back would have let me know it!

99SVT
08-07-2010, 04:29 PM
Main difference is piston dish volume, which would seriously affect compression.
Non PI heads 10.5cc dish 91-98
PI heads 18.1cc dish 99-00
PI heads 15.8cc dish 01-04
4V tumble port heads 4.5cc dish

Other than that, you may have to drill or enlage an extra hole for the timing cover/ timing chain guides. There were a few running changes depending on the year of the blocks and place of manufacture.

FordNut
08-07-2010, 05:37 PM
There are at least two different cast iron OEM 4.6 blocks. I believe there are two different 2V blocks, a Romeo and Windsor. The 4V Cobra block is also cast iron but I believe it is different from the 2V blocks.

An OEM aluminum block has weight advantages and is at least as strong as the 2V blocks.