The Stovebolt Site Forums The Shop Area Engine Shop 454 fitment in task force big bolt

I have searched here and read the threads but have a question. (I think I know the answer though). I am toying with the idea of replacing the 327 currently in my 58 Viking 60 with a 454. I have an SM420 behind it and I am not planning on relocating the rear mounts. I am assuming I will have the same fitment issues installing the 454 as I would putting it in a pickup of the same vintage since the width of the big bolt frame rails is the same as the pickup, is that correct? It will still be tight against the firewall, and also with the steering box.

i have seen a 396 in a TF 1/2 ton and the inner fenders were cut on that truck in order to get the steering and exhaust to work. I think you're looking at some metal work...

yeah, that is what I am thinking, and I really don't want to do all that.

If it was a LCF I don't think you would have much trouble, I bet I have 6 -8 inches between the exhaust manifolds and the inner fenders. the firewall would be tight and most likely need mods. My distributor and plug wires are real close to the sheet metal, heads and valve covers have a couple of inches clearance. Factory 283 with SM420.

yeah, not an LCF. currently a good running 327, but towing my trailer, I weigh in at 16K so, looking for a little better pulling power. Thinking a big block may not get any worse gas mileage because it is not working as hard as the small block. I have a Ranger OD unit I am going ti install. Currently, I am spinning 3600 RPM at 60 MPH. If I drop that with the OD, my small block may lose power at the lower RPM where the 454 may be happier and not sick as much gas! (3,000 RPM )

A 6bt would fit in there, better fuel mileage.

Ed

yeah, not interested in diesel, 2 options are staying with the small block or going to a big block.

I know it's not one of your listed options. What about a 400 small block?

John

we have done several big block conversions but none using the factory transmission which gives one no leeway for off setting the engine (steering box) or moving forward (firewall clearance). I would think the small distributor on the BB will clear but almost sure you will have to do a bit of BFH on the firewall for the rear of the right cylinder head. Small block 400's are getting hard to find but do have a lot more torque than the others. Here is a shot of a 1937 2 ton with a big block and a bubble for right head clearance---ignore the big bubble for an HEI distributor and look at the small one to the bottom right if the distributor one. This truck also has a shorty steering column with a U-jointed shaft to clear exhaust manifold; something you shouldn't need.

[img]https://i.postimg.cc/v4nQYK2x/37-Hauler-Don-s-for-sale-86-006.jpg[/img]

[img]https://i.postimg.cc/3WkzQvcd/37-Hauler-Don-s-for-sale-86-005.jpg[/img]

[img]https://i.postimg.cc/N5hChPXz/37-Hauler-Don-s-for-sale-86-007.jpg[/img]

yeah, at this point, I really don't want to rework the firewall or custom make headers to fit around the steering. I am thinking I may leave the 327 in it and possibly do a big block later when I have the cab off to extend it.

Have you thought about a 383 small block? That would allow you keep your current SBC mounts/steering. You could have approximately 400 ft-lbs of torque at your target RPM (3K) with the right tune/cam.

SimS

thought about, yes.... but not looking to build an engine at the moment.... Thanks.

I did a 454 in a TF. Headers for clearance, ujoint steering rod. No firewall issues. Mock it up for radiator clearance and trans mount. Probably need a modified driveshaft. The 454 fits. Used universal tubular cross members for motor and trans mounts. (automatic)

Thanks Bartamos. I have stock steering, trans is an SM420 and I wish to retain stock trans placement so, I will have a bit of firewall clearance issues and probably header to steering as well.

I have heard, and it makes sense to me, that the marinized GM small blocks (Mercruiser and Volvo-Penta) are cammed for torque peak around 2500-3000 rpms. Would a marine cam in your 327 move the torque curve down to lower RPMs to optimize it for truck use? I'm sure they would be easy to find. there are "RV" cams available, too, from Crane, etc. I guess what I'm saying is that its much easier to re-cam your 327 than do an engine build. no problem swapping the cam with the engine in place...

I drove a lot of 366 and 427's, 4spd x 2spd and 5spd x 2spd. I think our elected GVW was 24000 on the straight trucks and 420000 - 48000 on the single axle tractor-trailer rigs, plenty of torque with those motors. I don't know the external dimensions compared to the Mark IV but maybe HRL knows. I'm kind'a glad my beer delivery days are behind me. I have a 383 on the cradle that I built for the Vette but never have swapped it, all wrapped up waiting for a home, when I had the 283 out of the '57 for clutch and cam I thought about sticking the 383 in but I like the original motor in the truck.

I am leaning towards freshening up the 327 and putting a cam in it for lower torque. Jerry (HRL) had recommended a Comp Cams 268H for a different build, not sure if that would be a good choice for this or not. I am also putting a Ranger OD between engine and trans that should give me a bit better mileage on the flat, especially when empty. Right now, the engine spins 4200 rpm @ 70 mph going down the freeway, 3600 rpm @ 60mph. I don't want the torque curve too low! LOL

If you call Comp Cams and give them all of the info they will recommend a grind. I did that when I built the 383. told 'em it would be a low RPM motor since the Vette has a 3.08 rear end. If I ever put the motor in something it should be a pretty good stump puller. I can't remember the cam number. Do you still have the original rear end in the truck, two speed?

yes, original 2 speed. The previous owner bought the truck new (his dad did) and then somewhere along the way, they replaced the 235 with a 1967 327. It runs fine but smokes and leaks a bit. I may pull it out, cut the ridge, hone it and put rings/bearings/gaskets in it along with changing the cam. I also have a stuck 4bbl manifold and q-jet for it (also off a 1967 327). If I putt it apart, I will probably have the heads gone through and new seals and probably hardened valve seats. I just didn't want to buy another engine and completely rebuild it. I don't think this one has been apart before. (except me putting a new balancer, front seal, timing set, and oil pan gasket in it). I pulled a rod and main cap and I think they were std size still.

When you get to the time you do a serious overhaul I'd check out the stroker kits. Your 327 already has a 4" bore so a 3.5 stroke crank (350) would make a big difference and the 3.75 stroke (383, 400) makes a huge difference in torque. The kits are getting down in the price range where one can give them serious consideration. As suggested a good cam grinder can work with your gearing, weight, and tire size to come up with a good grind.

When it comes to making low RPM torque the longer the stroke the better. Right off-hand I don't know of a V-8 that isn't oversquare but I may get corrected on that. Back in the mid seventies I worked for a drainage tile company, we plowed in plastic tile with a D9 Caterpillar, that engine had a 6.25" bore and a 8" stroke, six cylinder, 1472 cubic inches. Needless to say that tractor made the earth shake. If you are going to add the overdrive to your truck then you'll want as much low end grunt as you can afford.

agreed on the low end grunt. I am going to take it one step at a time. OD and 4bbl first (4bbl has the vacuum port to hook up the vacuum advance on the dizzy) and then see what that does to my gas mileage. Hopefully, improve a bit going down the freeway! I may very well end up putting a 454 in it, but I think with the fitment issues, I am not going to mess with it at the moment. (although there is one local that was supposedly rebuilt recently, the guy wants 800 for it, still in the motorhome... I can hear it run).

Mike,

How would you mount the BB and keep the SM420? You'd have to keep the bell housing with it's side mounts and add a cross member for the side mounts on the engine.

Quick and easy...drop a new 350 crate engine in (something mild in the 200-220 hp range) and call it done. That would almost be cheaper than rebuilding the 327.

Mike B

Or a 383 crate motor, all the same exterior dimensions as the 327 and 350 but with 3.75" stroke.