Big block swap

[Dan Murphy]

Need some advice. Have a 67 J3000 w/327 and T18
transmission. Engine needs rebuild, so instead of sinking money into what is basically an obsolete engine I was thinking about utilizing a 454 chevy that I have access to. I want to utilize my transmission if possible, need to know what is goint to be involved as far as adaptors to make this swap work. Just a shadetree mechanic myself, but I do have a son who knows his way around a wrench and is ready to help. Any information would be greatly appreciated!

[LRRH]

you will need an adapter to go from the engine to the T18. The T18 should be beefy enough to hold up to the big block. I'm sure you'll also need motors mounts and the such.

[AJ Johnson]

I just did a 454 swap into my 69 J3000. there are a few little quirks that you need to work around. Mine had already been converted over to a SBC 305 when I got it and it was mated to a TH400 tranny, so the tranny part was easy, just bolted it up. BUT one problem you will have is the cooling fan. the 454 that I got had a fluid clutch fan, and those have a pretty long shaft that will put the fan RIGHT in the center of where your radiator sits. You will have to either use a different fan, and make sure that it will clear your alternator brackets, or go with a dual electric fan setup on your radiator. get the biggest electric ones you can find and mount one on either side of your radiator, making sure that one is pushing air through it and one is pulling it through the other side. ALSO, very important... make sure that the engine you are getting has the accessories with it, like the alternator and the power steering pump. I have one helluva time finding a power steering pump bracket that fit a 454. they are different than a small block, and if you don't have them... good luck in finding them. Also, this is just my personal opinion, but if you are going to put a 454 in, you would really be better off in the long run by changing over your drivetrain to match it at the same time. I don't think that the T18 tranny is all that tough for the amount of torque that the 454 puts out. I'd swap in a TH400 and bolt it up to a D20 and go that route. It seems like alot of work, but if you can get all your parts lined up ahead of time, it should go fairly quickly. Keep me posted...

[curt]

Call Advanced Adapters, they have the goods you need and have helped thousands of people with swops like that.

[Mikel]

Novak makes a T98/T18 to Chevy adapter. I have just sold one to a forum member smile.gif

[curt]

AJ, why do you think a t18 will not handle the torque? Very curious because that is what I am going to be using in my 73 with Buick 455. I'll be pushing a ton of torque out of the 455! I thought the t18 was VERY tough, actually a t18a, which would be the same as Dan's 67.

[ColeTrickle]

Curt, from what I've read the T18a is VERY stout.

Mr. Johnson, could you shed some light on why you don't think so?

I was talking about this last night on IRC and Retro93, had suggested in purchasing a beefier output shaft to remedy the D20 that'll be seeing my Ford BB's torque.

[ August 07, 2003, 02:24 PM: Message edited by: ColeTrickle ]

[Smooshy]

The t-18s actually have been used in some 2 ton trucks and school busses. And I am running a 380+ horse 360 (?torque) against a t-18... Cant imagine a 454 being too much unless it was built for race...
Building a 450+ horse 401 for my t-18 also smile.gif

[curt]

Cole, you lost me on the d20 shaft part. I'll be pushing over 400hp with the 455, it there somthing I should worry about with the d20?

I hope Mr. Johnson comes back to this. VERY curious......

Sorry Dan, didn't mean to sidetrack your post.

[Will Morris]

Originally posted by curt:
[QB]Cole, you lost me on the d20 shaft part. I'll be pushing over 400hp with the 455, it there somthing I should worry about with the d20?QB]Yeah, D20 output shafts are 10 spline weaklings. Nick twisted his in half with his 360. There's a 32 spline upgrade for like $500 or so from Advance Adapters or Novak. I forget which.

Will

[ColeTrickle]

Originally posted by curt:
Cole, you lost me on the d20 shaft part. I'll be pushing over 400hp with the 455, it there somthing I should worry about with the d20?

I hope Mr. Johnson comes back to this. VERY curious......

Sorry Dan, didn't mean to sidetrack your post.Hehehehe, only thing you need to worry about is COOLING!!! tongue.gif
I was up in Ouray with a guy who had a stretched CJ-5 with a 455 Olds...man he couldn't drive for more than a mile without that thing boiling over. Sad thing is, it's been like this on a number of runs and no one can figure it out :confused:
He ended up renting a TJ the following day for the next trail run :rolleyes:

$500.00??? :eek: I hope not, I'll be checking though.

[Stuka]

have fun with the distributer :D

/me likes fords :D

[AJ Johnson]

the distributor wasn't even a problem with mine.. I still have probably 2-3 inches of clearance to the firewall, and didn't even have to pull it when I dropped it in..
As far as the T18, first, let me say that I've never had one or drove one.. this is just personal opinion based on a couple of friends that put a caddys in their scouts with that tranny, and both of them busted gears in it. now, I don't know what they were doing when it happened, I just remember hearing that they had busted gears in it and knew that they had caddy 500s. sooo... i'm no expert on manuals (obviously)but that was my thinking when they busted them.

[Stuka]

They broke T18a gears? Its a 2.5 ton rated tranny. I know a few 4x4 puller trucks with around 800hp that use them without problems. They must be REALLY tuff on them ;)

[AJ Johnson]

well, lol.. after callin one up to see Great Googley MoogleyGreat Googley MoogleyGreat Googley Moogley, he told me that he had cracked his case somehow and lost all the gear oil, and that is why it fried.. the other one I still don't know about tho..

[Dan Murphy]

Well, it appears that this may not be too complicated a job. I was concerned about the distributor( clearance), but it does not seem that it is going to be a problem. As far as the cooling issues I will take lots of measurements to see where I am going to end up as far as engine placement. It seems that Novak has everything I may need as far as adapters and mounts (to the tune of about $500.00) but I have not looked into Advanced Adapters, they may have what I need for less. I will also keep my eyes open for something used,something may turn up. I have heard from lots of folks that the T18 will stand up to most anything, and I do prefer a standard transmission so that is the way I am going to go! I appreciate all the feedback, there is a wealth of information here, with plenty of people willing to share it!

[Stuka]

Originally posted by AJ Johnson:
the distributor wasn't even a problem with mine.. I still have probably 2-3 inches of clearance to the firewall, and didn't even have to pull it when I dropped it in..What I ment is taking the distributer out now. Picts I saw of a 454 in an FSJ looked like the distributer wouldent come out because of the firewall curving over the engine a bit. (that little lip up there)