350 to 454 swap...is it worth it?

[baclay9]

As some of you know I am currently building an 83 Swb fom the frame up. My plan has been to just put the plain Jane 350 back in it. I have kindof had another motor dropped in my lap and I just don't know what to do.

When my dad bought his 84 3/4 ton 4x4 it had a pretty hot 454 in it built by Watson Rupel Performance up in Ohio. He has never been real happy with it due to it's fairly big lope and it didn't do real good running his a/c without turning the idle up. He broke down and bought a 454 crate motor and we pulled his 454 today and broke it down to a long block. He gets a $600 core for sending it back to the motor company.

After tearing it down though I am seriously considering putting it in my 1/2 ton. I don't know alot about engine stuff but it looks like a very well built motor. From what I can see it has crane cams roller rockers on it. I assume it has a crane cam in it as well but really don't know how to tell. I also don't know how to tell if it has a good set of heads on it. The intake ports are oval. It is a 4 bolt main block and I believe it is bored .60 over. I had a guy that looked at it tell me it had Teflon coated pistons. I think he said they were "speed pro pistons" (dos that sound right?) He also showed me where the crank had been balanced. He said it was most likely a really good motor.

I was curious if it sounded like this might be a pretty strong motor to you guys. Any other suggestions of things to look for. How do I tell if it has a good set of heads on it? All my dad wants for it is the core charge of $600.

I was also curios how hard it would be to slip this into my 1/2 ton backed by my TH350?

[PRattenbury]

It would be a real easy swap assuming you have the engine hoist and so forth. If I was you I'd do the swap, but I'd get rid of the lumpy cam and go with something less lopey if you plan to run it on the street. As they say, there's no replacement for displacement!

[tucsonjwt]

In my opinion, a 454 needs a TH400 transmission. 454s had "soft cams" for a while (had to replace mine) so make sure you have a good truck engine cam in it.

[S10Fan]

I have a 454 in mine, bone stock except for the intake and 670 Holley. A 700R4 handles the gears. I love mine and I especially love the motor being STOCK. Smooth idle, reliable, and I still get the "Wow" factor at car shows/Cruise-Ins.

[Hottrucks]

I wouod hit craiglist for a cheap core

keep what you have and run the ass off it BB rule I did the swap a few weeks ago on my 70 and its the best thing I have done hands down

[BigBlocksRule]

As long as it doesn't need rings, etc., it should be fine. Post the casting numbers of the heads, that'll help.
As mentioned earlier, swap cams and you'll be happier. Big ol' lumpy cams are fun to listen to but can be a pain to drive. Stick with something in the 230-236 range and you'll be fine.
You generally can't buy a good longblock for much less than that and if everything is in good shape and it doesn't need to be honed, etc., it's worth a good bit more than $600. Most 4-bolt blocks sell for $350 - $400 bare...

[baclay9]

The only way I am going to do it is if I decide I want a lumpy cam. I don't want the big block just to have one. If I go this way I won't be running a/c and will shave my fire wall. I just don't know what to do. I will try to get the casting numbers tomorrow. Where are they?

The truck is going to be bone stock inside and out only lowered 5/7 and sitting on 20's. I think a mean sounding motor in a stock looking truck would be pretty cool. I wonder how much lower the front of the truck would sit with the 454 in it vs the 350.

By the way. This is not going to be a daily driver. This is going to be a weekend cruiser just for enjoyment. In no way a primary mode of transportation no matter what I decide.

[BigBlocksRule]

Casting numbers are on the valvetrain side of the head. Pull a valve cover, they should be 6 - 7 digits.
BTW, a big block will have more than enough torque to do anything you want, even with a much smaller cam. Lumpy cams are a ***** to drive in the cold weather and tend to foul spark plugs if just used for cruising. A cam in the 230-236 range will have plenty of chop but still be very streetable.

[baclay9]

Originally Posted by BigBlocksRule

Casting numbers are on the valvetrain side of the head. Pull a valve cover, they should be 6 - 7 digits.
BTW, a big block will have more than enough torque to do anything you want, even with a much smaller cam. Lumpy cams are a ***** to drive in the cold weather and tend to foul spark plugs if just used for cruising. A cam in the 230-236 range will have plenty of chop but still be very streetable.

cool deal man, I will check it out. Let me ask you this... How do I tell what cam is in there? It had a fair amount of chop to it but it was nothng rediculous. Would it say somewhere on the cam?

[BigBlocksRule]

Some have it etched on the front of the cam, it'll be behind the timing chain cover, though. No guarantees that it'll even be there.
How choppy is the idle now? If you can stand it, give it a shot for awhile and decide later. Cam swaps are a pain and with today's oils, it's easy to screw one up during break-in.

[baclay9]

It is honestly hard to remember. When my dad got the truck I remember it being fairly choppy. He wanted the ac to work well with it though so he had it idled up so it wouldn't die when the compressor kicked on so it hasn't been idleing correctly for a while. I do think I will run it the way it is for a while though. Another thing is my dad has been running 87 octane and you can hear the litters "clattering" when you get in the gas. It doesn't seem to do it when running on 91 octane though.

Should I put like a 750 edelbrock carb on it? Single plane Intake? I was thinking maybe headers and a 2.5" exhaust with like an H pipe. I would think it would run pretty good.

My dad also told me tonite that I could just have it if I wanted it so it sounds like it might turn into an ok deal

[joe231]

Do it!!!

[BigBlocksRule]

Sounds like you have a higher compression engine. That's not lifter clattering, it's detonation. Keep the good stuff in it, detonation will kill the engine, literally.

[gloriavoxdei]

No question, do it!!! I have a stock 454 in my dually and is blows the socks off the 350 k25 I had years ago.

[baclay9]

Thanks guys. I am going to take some pics and get those casting numbers tomorrow night. Maybe someone will be able to spot other things that are done to it from the pics.

[baclay9]

OK got a little more info.

Head casting # 14081045
Block # 14015445

What can you tell me based on that.

I took a pic of one of the rockers and springs. The springs have like spacers under them.

I pulled the valve cover gasket off and under it written in sharpie are numbers directly below each spring. Numbers like 1.850, 1.870, ect. Each spring has a # written under it.

My pic doesn't want to upload right now.

Also let me ask some of you that may have done this swap something. What will I have to do as far as motor mounts? Will this thing literally drop right in? I know I need a BB radiator and will have to get new bb radiator mounting hardware but what about physically putting the engine in. What about headers? Which ones will fit?

Thanks in advance for any info on the heads or anything.

[BigBlocksRule]

Those are small port heads, made for max torque on the bottom end but they'll run out of steam around 5000 rpm's. Better heads are open chamber ovals, look for the last 3 digits to be 781 or 049. They're fairly common, expect to pay about $150 for a pair of cores. The ones you have can be made to work with some porting and bigger valves, but the castings I listed are much better from a performance standpoint.
That block is one of the more common ones, should be a good one.

[baclay9]

I understand these are not the BEST heads from a performance standpoint as you said but should they be ok for a street driven truck. I mean I would like to have something I can romp on every once in a while and have some fun in but it doesn't have to be the fastest thing around.

How can I tell if they have been ported and possibly had some valve work done? I can't believe they would have put all this other stuff in this motor and not have done something to the heads.

[BigBlocksRule]

If he spent a bunch upgrading the rotating assembly and kept the peanut port heads, it wouldn't make much sense, either. They'll make decent power and keep you from over-revving the engine, they won't flow enough air to get you in trouble.
As long as you have the heads off, I'd upgrade 'em to the 781's or 049's. Even in stock form, they'll make more power, although they'll give up a small bit of torque on the bottom end. Put an ad in craiglist, you should be able to find a set fairly cheap. As long as the valves are good, leave 'em stock size and get a good valve job, pocket port 'em and you'll be set. Advertise the heads you have as high-torque, someone with a tow rig or motor home will want 'em, that's what they're made for.

[Jonboy]

If you are going to go 454, I have a TH400 that would be awesome in that too. It was rebuilt about 20K ago, and I have the reciept. It is in my dually right now, but I am planning on going 4L80E pretty soon.

The engine will drop in using the existing motor mounts you have now. headers are pretty readily available, just look for BB headers for an '83. It will most likely make the truck ride about 1" lower in the front, once your springs settle. If you are going with new springs, it may not be as much. You might want to check with the place you are getting your lowering parts from to be sure, though.

[baclay9]

Originally Posted by Jonboy

If you are going to go 454, I have a TH400 that would be awesome in that too. It was rebuilt about 20K ago, and I have the reciept. It is in my dually right now, but I am planning on going 4L80E pretty soon.

The engine will drop in using the existing motor mounts you have now. headers are pretty readily available, just look for BB headers for an '83. It will most likely make the truck ride about 1" lower in the front, once your springs settle. If you are going with new springs, it may not be as much. You might want to check with the place you are getting your lowering parts from to be sure, though.

First off, Thanks BigBlocksRule for your help. You have given me alot to think about.

Jonboy, let me know when you get ready to do your swap. I may just go ahead and pick the TH400 up from you. I was planning to just put the TH350 behind it and run it till it grenaded, but if you do pull yours and the timing is right I may go ahead and get it. It sure will be easier to set it in the bare frame then to put it in after the truck is together.

I found 87lowriders BB conversion thread and got alot of good info from him as well. I am thinking about running the same BeCool radiator and electric fans he is running. I probably will be using alot of the same stuff he did since it worked so well for him.

I have decided I am definately going to do the swap. Just for the wow factor if nothing else. I have a buddy that has a pretty hot 350 in his 84 SWB and I am hoping it will blow him away.

[joe231]

I'd just run the heads you have for now, lots of torque in these trucks is a good thing.
Besides, how often do you plan on running it above 5000RPM?

[willett]

get a th400 and dooooo it!

[b454rat]

My old 84 had a stock rebuilt 454, 781 heads on it. Stock intake, Edelbrock 600 carb, headers off a Chevelle and some homemade exhaust with fake flows. Truck was a short box 4wd, 4-speed, 35" tires and 4.10 gears. I could start out in 2nd easily, pull any hill in 4th and accelerate if needed, but would still cruise down the highway at 70mph around 2500 or so RPMs.

And if it wasn't for a slow to shift tranny, the truck would be much faster than it was. No such thing as shifting an SM465 fast, but would make cars much smaller looking thru the rear view mirror. And rarily did it ever hit 5k RPM, didn't really need to.

Everybody has a small block, don't see alot of big blocks anymore. Big block have their own sound, and will walk away from a similarly built small block.

[baclay9]

I got on CL and found a 454 to use as a donor for some of the parts i need such as Harmonic balancer ect.. I picked it up for $350 and after I get done stripping it I am going to send it in as the core for my Dads motor so I will get the $600 back on that. So I will actually make money on this deal.

The motor I went and got had a Holley Street Dominator single plane intake on it. Is this a pretty good intake? I think I will probably plop a 750 Edelbrock onto of it with the extra money I get from the core. Here are some pics of the intake.

From reading its description on the Summit site it seems like it is made for really high RPM's. Maybe I would be better off trading it for something else???


By claypool782 at 2010-08-31

By claypool782 at 2010-08-31