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Alright fellow bolters. I have read and searched till I am blue in the face. I finally have got some direction, however I wanted to get the opions of others on here and do a sanity check on myself. I have several project trucks (total of 3 and 1 for parts) that I am working on. I recently bought a 50 3100 with a 55 235 (high pressure) in it. 3 on the tree. I got it running very well but feel that it's nothing more than a parade vehicle (due to the brakes, suspension and gearing of the engine). I have started to persue a t-5 swap, and located a 88 firebird posi rear end with disc brakes. So far so good. The bad part on the truck now is one of the front main leafs is broken at the eye (no biggie) The question that I have are this, I also found a recent 67 Inline 250 with a 2 speed power glide out of a 67 camaro running as I was told. By swapping that motor in, I can put any current GM trans behind that motor. Or, would I be better off doing the t-5 swap, then later planning on a v8 Small block. The idea is I want to be able to keep this vehicle "drivable" while the other 2 go through major surgery. What do you think?

The "other 2" are a 51 D*dge with Air ride, 4wheel disc brakes, rack and pinion, custom IFS, f*rd 9" rear end, 4 link with pan hard, powered by a 95 LT1 and 4L60E. The other is a 47 Stude on a 1987 D*dge Dakota chassis with all original driveline.

If all you want is to have a driver while working on the other two why do you want to do anything other than the repairs the 50' needs? Sounds like it has a decent engine and if the trans is good then why mess with anything other than the spring? If you really want to upgrade it then go with the 250/PG and get the rear end from the Camaro and you've got yourself a better driver. The Camaro would have drum brakes and unless your going to totally change out the front end it makes more sense (to me) to stay with the drum setup. Otherwise your talking about major surgery on all three trucks.

That has kind of been my feeling. Will the 250 bolt in just like the 235?

The 250 is not a simple bolt in. The T-5 is a fairly easy swap except you have to change the rear end on that model. I believe the latter model center section will fit your housing. Some other bolters might help out on that. In my oppinion that would be the easyest way to get the truck useable.

Well I am not against changing the motor mounts (I have welder, plasma cutter in my garage) so fabrication is not a problem. So it's starting to sound like I should repair the front spring, and do the t-5 swap. I also have been reading that a blazer 4x4 rear end fits well under the truck. I have several rear ends lined up, 1 out of a 97 blazer 4x4, 1 out of a 80 something camaro, and 1 out of a 80 something firebird. Should I go for the blazer rear or the camaro? I can get all of them for the same price. What's the suggestion on that?

I think that late model Blazer is way too wide. You may want to measure it & see. The Camero & firebird are 5 lug so you would have to change the front to match or use different wheels.

I own a 96 blazer, I will go out and measure it as well as the original rear end and see what I come up with. I was reading on here that some people used the blazer rear ends, I guess that's where that idea came from.

the blazer should fit.
i have two friends that fitted standard blazer rear axles on their trucks.
I have a full size suburban rear end under my 3104 and it fits just fine .

There are lots of rear ends available! Some fit better than others. For 6 lug rear ends, the 64-69 1/2 ton 2wd Chevy (and some GMC) trucks have a 12 bolt rear, about 60-61" wide (I measure them where the wheels bolt on). The 70 2wd and 70-81 4wd have a 6 lug 12 bolt that is a couple inches wider, but will fit under an Advanced Design or Task Force truck as long as you don't get too wild with wheel/tire width. The heavy duty models have a 2.75’’ brake shoe, that’s stopping power. The 12 bolt truck rear ends from the 60s usually had 3.70 gears, which is a bit much for extended highway driving at 75 mph. (unless you hgave a 5 speed), You can swap the differential carrier and ring/pinion gears from a later TRUCK or VAN 12 bolt, the 70s trucks usually had 3.08 or 3.40 gears. Of course, you'll need to know how to set up ring/pinion gears, bearing preload, and all that other neat stuff to do this. These 60s truck 12 bolt rear ends are from coil spring trucks, so the perches are in the wrong place, and they have some extra stuff on the housing for a panhard bar, which you won't need with leaf springs.

BUT
don't take my word on it
see: chevy trucks. org
http://www.chevytrucks.org/tech/rear_ends.htm

The Blazer rear ends that work well with AD trucks are from the S-10 based vehicles, the full size blazers are a few inches wider and will cause the wheels to stick out of the fenders.

My S-10 Blazer is about the same (62" on the 3100 and like 63" on the S-10).

Well I landed a T5 transmission and a rear end out of a 88 Firebird with disc brakes. So as soon as the weather gets better, I will be putting that in. Also from the guy that I got the rear end from he had a complete low mileage SBC for $150. I will probably get that later this year.

I think I also have a Chevy floor pedal assembly, corvette master cylinder and 9" single diagphram booster left over from another project. I think it might be happy in the old Chevy.

Now to start looking for a decent disc brake kit for the truck.

Thanks for all the input. I will post pohotos on my project journal at: http://www.hotrodders.com/forum/journal.php?s=&journalid=22733&action=view

If you are putting rear discs on, you do not want to drive it with drums on the front. It could lead to some major stopping problems. If you did drive with rear discs and drum fronts, you have to switch your metering valve and proportioning valve around and it would still be scary. Just my $.02.

Absolutely. That's why I am planning on picking up a front disc brake kit while I repair the broken front leaf spring. Then replacing the master cylinder with a power booster and a corvette dual master cylinder, adding the prop vavle and residual valves. (2lbs for both since it will be disc/disc). I have already stared to do this on my 51 D*dge project. So it's nothing new to me! Thanks for the $.02 cents though! I wouldn't do it any other way!

a nova rearend works quite well i have it in my 54 with the t-5. ron

Ron, how are you liking freeway speeds with that? That is my goal, is to be able to drive this a good distance without winding up the eninge and having to drive in the slow lane.

I put a Chevelle rear under my '55 1st Suburban. 62" wide with 3.08 gears.

With a stock SM420 (granny gear 4-speed) it runs down the highway just fine up to 70 or so. It has enough other problems that I rarely run it that fast, but winding the motor is no longer one of its problems.

I used a disk brake kit from Chevy Duty (read other threads to get my negative opinion of them) that put GM mid-size disks on the front. I now have the complete braking system front and rear from a '73 Chevelle wagon, including the master cylinder and combo valve.

Changing only the rear and the brakes turned mine into a great driver. Of course on yours you'll be forced to change the transmission also.