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Discussion Starter #1
Hey guys. Thinking about a big block swap in my 56 210. Just how much firewall massaging is really needed to install the motor in the stock position with short valve covers?
 

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I've done it before (waaayy long ago) with a BFH. Then moved on to doing it on another car later with another BFH and a trailer ball welded to a pipe. Either of those is a VERY hard method to use physically because the firewall at that point is very-very stiff..

This time I cut the offending area out and welded in a formed piece off the back of the cab of a trifive pickup. There's a depression in those cab rears that works perfectly. It just has to be studied.

If you use forward from stock side mounts you won't have to cut or pound anything, but there's also other things that have to accounted for like exhaust, tranny shifter hole, driveshaft, on and on. Just seemed like a lame way to do it to me too by moving a heavy engine forward so I chose to move other stuff instead of an engine.

You can also go the pocket or entire firewall replace method if you want. They are available out there. I just stuck with what little ingenuity I had, and did it my way though.

I did most of the work on the pass side because of the engine cylinders offset, but did do a smaller recess on the drivers side too. This pic is of the 'during', but when I find my pic of the after I'll post it here too.

Now I can run any covers I want without any hassles.

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Here's a link to my thread if interested.
https://www.trifive.com/forums/showthread.php?t=109163&highlight=paladin
 

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Thanks for the reply. I looked at your thread, really nice work. I dont have a welder and certainly not your fab skills so a BFH it will be if i decide to do it. Still on the fence about it. Other than the firewall and headers it seems fairly straight forward. How much hammering would need to be done? An inch or two or more than that? The motor i have is a mark iv 454 thats .030 over with an rv-towing cam.
 

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Thanks for the reply. I looked at your thread, really nice work. I dont have a welder and certainly not your fab skills so a BFH it will be if i decide to do it. Still on the fence about it. Other than the firewall and headers it seems fairly straight forward. How much hammering would need to be done? An inch or two or more than that? The motor i have is a mark iv 454 thats .030 over with an rv-towing cam.
Doesn't matter if it's a stock 396 or 1000hp 632, it still needs done.

The problem with using the hammer method, is that the very last 1/4 needed takes lots and lots of heavy blows. Every time you think you're done there's more left that's needed. That last 1/8 inch takes more time and effort than ALL of the rest of it does.

Doing it for just a set of short covers helps a lot, but it still takes some effort. I remember that after I started using the trailer ball technique things got a bit better, but still found myself spending a couple hours of heavy and frustrating effort to get it all to clear. Not young enough to want to go through THAT again.

Not saying it can't be done with just a hammer, but.......

You don't have to own a welding shop or be a fantastic fabricator either to do a pocket kit, or do what I did. I did mine with just limited skills and a little Lincoln 110V mig welder that I still have and still use it for all kinds of stuff around my house. A hand grinder with cut-off discs and some grinding wheels for it does amazing jobs too for that purpose.
 

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Discussion Starter #5
Thanks again. Thats what I wanted to know. If it takes that much hammering than it sounds much easier to cut and weld. Maybe its finally time to buy a welder.
 

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if the radiator is in the 6cyl position it can be done without touching the firewall.
 

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if the radiator is in the 6cyl position it can be done without touching the firewall.
The mounts hold the engine in the same position John. Even if the radiator is suspended six feet out the front the rear of the pass head, and especially the valve cover will still hit without clearancing the firewall. And I mentioned the forward mounts and their hassles above, if that's what you're thinking.
 

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With the back of the engine in the stock position, hammering the firewall to make a BBC fit is only for brutes and those with power tools.

If you move the engine 3/4" forward (and there are commercially available mounts for that) you still have to hammer the firewall but you don't need to be a brute, at least much of one. You'll also have to do something with oil pan clearance to the steering linkage, but again there are solutions readily available. And you may need a longer driveshaft depending on transmission.

You could move the engine 1-1/4" - 2-1/4" forward and have the engine clearing the firewall nicely (commercial mounts for that too), but the oil pan becomes more of a problem and it gets crowded at the front of the engine with respect to the radiator.

The cleanest solution is the 3/4" forward, at least to me.
 

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The mounts hold the engine in the same position John. Even if the radiator is suspended six feet out the front the rear of the pass head, and especially the valve cover will still hit without clearancing the firewall. And I mentioned the forward mounts and their hassles above, if that's what you're thinking.
if you do it smartly, moving the engine forward, you do not have to beat up the firewall. you will have to mod the oil pan but it is easy to do, something like you do with a sbc in a chevyII. it also helps with the number 5 exhaust port to steering box clearance issue. did it a couple times years ago before digital cameras, I never had time or money for fil pics. wish I had those now. as I remember we also raised the rear of the engine and lowered the front a little, surprising what that will do.
 

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Discussion Starter #10
Thanks again for the info. This is why I'm undecided. No matter where the motor sits. Is it worth the effort to have a big block, or put that money and time into the small block?
 

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I remember having to Beat on the right side of the firewall on two different 55 I had both had the hurst BB front mount & used the rear mounts with a 4 speed but I don’t remember having to do a lot to get clearance I did always run the stock valve covers & I think but not sure I used the left cover off either Chevelle or corvette that had a relieve on that side that helped. Also would have been a small cap point distributor & the oil pan was a GM part number for L88 deep sump cleared steering fine but the engine wasn’t moved forward any
 

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I personaly think the better value is a small block with some modern heads. less weight up front and a lot less headaches. a BBC has a cool factor but it comes at cost.
 

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That’s probably a smart way to go but I do love the looks of a big block in a tri five & as much as I like my LS stroker if I had it to do all over I would be tempted to do a nice 427 BB and spent a great deal less $ in the process
 

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as much as I like my LS stroker if I had it to do all over I would be tempted to do a nice 427 BB and spent a great deal less $ in the process
you will spend just as much on a bbc as an LS, usually more.
 

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I had some bashing in on the right side that was quite a bit. The left side was minimum amount on the vertical forward edge. This is a ‘57 Nomad. Please excuse the undressed wires. Some redesign of the contour was done to look somewhat factory. But if you know what it looked like as original the illusion is exposed. Tall valve covers would not fit. More firewall displacement would be necessary for that but the shorter stock type was my preference.

I’m doing some reconfiguring during this virus time. Adding heavier wiring and relays for starter and ignition which were upgraded too.

I don’t have any heater components as this car only sees perfect weather.

There would be issues if the heater parts were desired. Some modifications would be necessary just to fit the new lip contour. But not being concern with foul weather driving it is what it is.
 

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you will spend just as much on a bbc as an LS, usually more.
The basic engine may cost just as much to build depending completely on how either one is built the difference is in all the supporting components necessary to do the LS & that’s doing everything yourself if you are paying a shop to do that for you then add 2-3000 Myself I hate to even pay for a dyno but haven’t had a choice till now & the release of the newer self tuning systems which is what I would now do
 

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The basic engine may cost just as much to build depending completely on how either one is built the difference is in all the supporting components necessary to do the LS & that’s doing everything yourself if you are paying a shop to do that for you then add 2-3000 Myself I hate to even pay for a dyno but haven’t had a choice till now & the release of the newer self tuning systems which is what I would now do
a year ago I did a cost per engine analysis for a customer sbc, bbc, and LS. the basis was starting from scratch with an empty engine compartment and using a carburetor. the LS was in the middle only about 18% more than a sbc but a BBC was 22% more than the LS. this was including brackets pulleys power steering pumps ignition system, cooling system, etc. he asked about doing the LS in the efi config and after doing the math for all the efi going the holley rote it was still 5% less than a BBC. and yes I do it all my self. I only farm out the machine work on the engine.
 

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Seems that allmost everybody is going LS nowadays...just wondering where are those fresh bbc's and small block's guys are taking out? You would think there are smoking deals out there.
 

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Not here to argue with anyone only stated I could have installed a BB in my own personal 56 at a cost less than what I spent doing the LS swap Love the finished result & yes only work farmed out was machine shop work only on the 408LS3 & tuning after up & running this is my 4th ls swap in each case the addition of the induction system fuel tank & pump engine harness computer & accessory drive set up ran in the neighborhood of 2000 -$2500 more than what would have been needed to go either SBC or BB granted now that Fitec Edelbrock & Holley have more complete systems for doing LS swaps cost may be a little less considering a self learning system. I easily could have built from scratch as I did my Ls a carburetor equipped BB with decent power for equal or less & wouldn’t had the additional cost of the above mentioned components again just my opinion based on just a little experience
 

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Thanks again for the info. This is why I'm undecided. No matter where the motor sits. Is it worth the effort to have a big block, or put that money and time into the small block?
Thread was titled "bbc in 56 210". No mention of any other motor. Most answers given pertained only to that question.

It kinda sounds like you already have a BB and it's ready to install. If so stick with it and make it work. In the end you'll have something most don't these days. If later you decide you want something else you'll have a car that will accept most any power plant, so it's worth it to make this work regardless of effort. You'll learn a lot in the process too.

If memory is correct I believe Earl Williams makes some adjustable side motor mounts that allow you to move the motor around some to make room for header/steering box clearance, etc. Seems that they also offer the firewall pocket kits too. You might want to look into that.

After the firewall hassles are done with and motor is mounted in car you'll be a happy camper. Put the blinders on and focus. Many thousands of guys have done the same right through completion, so you're not alone.

Please post progress pics all the way through. Doesn't matter if everything is absolutely perfect either. We all know that you are a guy doing this in your garage. I'm the same, along with many others here.

Good luck man!

Just something I found while looking on the net, but I believe this pic involves the Williams side mounts and pocket kit.

 
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