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Discussion Starter · #1 ·
Hey everyone, I have a 1990 Chevy 1500 short cab long bed, 33x10.50x16 tires, 6" Rough Country lift, I am getting 35x12.50x16's when I come across the money. I recently stumbled across a completely rotted out Chevy K3500 4x4 with a 7.4 and a 4L80E tranny. I am taking the rear end, engine, tranny, and transfer case out of that truck, and transplanting it into my 1500, I am going to fully box and maybe weld some added cross-members to add more frame strength. This truck is primarily my daily driver in the winter, and I take it mudding occasionally, and I tow snowmobile trailers here and there. I never towed anything more because the old 305 could barley pull its self up a hill due to the 33's. I want this truck to be able to tow basically anything reasonable. I know the 7.4 alone is going to be a huge upgrade, but I was wondering if there was any quick reasonably priced ways to get some more torque and horse out of it. I was thinking cam/heads? I plan on going long tube headers to dual magnaflow mufflers and turn outs before the rear tires, or turn downs after the muffler, I was thinking either 3 or 3.5" exhaust headers back. I'm not worried about having a fast truck, I just want to be able to haul anything, and pull people out when they get stuck. So, for me, torque is more of a goal then HP is. If anyone has any suggestions, that would be hugely appreciated. I plan on doing a full tranny re-build with a shift kit, and a rear end re-build and will be putting a possi unit into it.
 

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I'm sure you know you need to match the gears in the diff's front and rear..
the 454 truck engine is set up for torque.. way down low..
it'll have peanut port heads.. these engines are all done at 4000 rpm..
I'd leave it alone.. it's 400 ft lb flat torque curve.. and will run on 86 pump piss
 

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Discussion Starter · #4 ·
yeah, I'm going to match the gears, i think the 3500 rear end has 4.11's stock? maybe, I'm not sure, I'll know much more when I get it all out, as of now I'm out of school for semester break ( one full month of work, so i should have money to rebuild the tranny when i go back to school, and it's convenient because i have Automatic Transmissions class next semester, so i can do all my re-build there and get credit :) ) and as for gas; I run 91 pump in it right now, and synthetic oil, I always have, I just like knowing that I'm using the best gas I can, and the truck loves it. Anyone have any comments or suggestions on which muffler/headers would work best? I honestly haven't done a ton of research yet, I just want to get other peoples opinions before I go searching.
 

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what year is this thing..
it's mostlikely a roller engine... and maybe alum headed
and efi..
if you drop your old distributor in you need to change the gear to a melonized gear..
if keeping the efi, not a bad idea.. plan on pain with the gauges and the need for a speed sensor..
 

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Discussion Starter · #6 ·
the 3500 is a 1992, still TBI, so im going to swap a carb into it so i don't have to worry about computers. Less complicated, but I might do an EFI swap later down the road.
 

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A first gen TBI system is very simple and cheap to run. With nothing else changed a carb swap generally will make less power, get worse fuel mileage,and will not able to easily drive up grades off road without any stumbling. Unless you use a off road carb which is $$$. Of course you then need a stand alone computer for the transmission $$$.

A cheap and easy way to make a bit more power while still retaining the factory drive train is to let that engine breath better with a intake and exhaust that will work with your existing cam. The tbi will support these upgrades within reason without needing to be upgraded itself.

I myself am a fan of the sm465 mated to a BBC when used in a dd/towing application. While it is not a quick shifting transmission it is very tough in stock form. When the bearings do wear out and it needs a rebuild it is something you can do yourself for less then $200 compared to around $1500-$2500 for the 4l80. As far as overdrive is considered that is a manner of running the right gears.

For instance a sm465 with 3.08 gears gives the exact same highway gearing as a 4l80.

Final drive ratios 4l80 with 4401 and 4.11 gears running 35" tires

Transfer case

High
10.19
6.08
4.11
3.08

Low
27.42
16.36
11.06
8.29

Final drive ratios 465 with 4401 and 3.08 gears running 35" tires

Transfer case

High
20.20
11.03
5.24
3.08

Low
54.35
29.66
14.08
8.29

I do not want to discourage you from running the 4l80 transmission. If you do not want to mess with driving and converting over to a stick it makes sense. But, if you are using it based upon overdrive alone the craw ratio and lower cost to run a 465 may interest you.

If you want power compare the 11.03 to 6.08 second gear. You would need 45% more torque to move the same speed. In third you will need 22% more torque.
Now you are going to loose some of that power in shifting. But, once in gear the power is something you will notice.
 

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Discussion Starter · #10 · (Edited)
I've always wanted to make the truck a standard, I found a tranny for $150 but that's without the transfer case. Do I need to buy a new transfer case along with the sm465? And I'll need to buy a clutch and pedals and all that good stuff.
 

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Discussion Starter · #11 ·
I don't mind shifting. I'd rather be shifting then texting and crash :p I would prefer the manual to be honest. I just need to get a new transfer case now. And pedals
 

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Switching over to a 465 is not terribly difficult. Aligning the bell housing and adjusting the clutch may cause some headaches but once they are set your good to go.
I prefer to run a 2wd 465 and a divorced transfer case. It makes changing the clutch a whole lot easier and all of the 2wd's had 35 splines eliminating one of the few weak links. As for the transfer case you have the room for a divorced and having a divorced lets you have tons of options later on. The classic 205 has proven itself, is quite cheap, and is mildly upgradable. If your toque increases and your foot gets heavier you can easily step up to one of the more expensive divorced cases from atlas, scs, etc later on.

The best way I have found to make the switch is to head to your local pick and pull and find a truck with a v8 and sm465. A bell housing from a 350 will also mate to many 454's. I am covering my butt in case someone finds one that does not mate but I believe the bolt pattern is the same on all the v8 blocks. There are some BEEFY ones in some of the larger trucks like sidekicks with 454's that have a larger input shaft. While you can put upwards of 600lbs into these the lager input shaft limits your clutch choices. I drive fairy stupid(off road) and have yet to need one of the larger input 465's. The standard input shaft will stand up to a lot of abuse.

As for bell housing choices you have 2. They are either full or half that is not the technical term I know but works to describe them. The full bell housing can be found practically anywhere and almost all of them are aluminum. You can also buy a full one from next to any shop that deals with transmissions. It is really the way to go you will need the 153 tooth flywheel if you want to stick with stock ish parts.
The half bell housing lets you have a larger flywheel and larger clutch and is cast. Although I am sure some out there is making aluminum ones. The downside is that these are getting hard to find. If you see one off ebay or something good chance it is for a 420 not a 465. The piliot diameter ring is smaller on the sm420. It is 4.667" for the SM420 and 5.125" for the SM465 you can have the 420 bell housing machined to open it up. But I have never personally done it before. You also have to adapt a different slave cylinder mounting bracket as the half housing used a manual style linkage. It is a lot of hoops to jump through to get the larger clutch which is only 1/2 to 1" larger then the one used with the full bell housing.

The easiest approach is to find a truck with a 465 at your local pick and pull and pull everything. The bell housing, clutch, flywheel, slave, fork, bearing,(all the old parts inside the bell housing) also get the pedal, linkage, master, and hose. I have taken the aligning pins before out of a junk yard block and actually had them match up to my new block so if you can get them out easily that could not hurt.
Then align the bell housing. Here is just one of the many videos that will help:
Then take all those old parts down to your local parts store(when they are not busy) and get all new parts. Having the old parts will make it tons easier to order new or upgraded ones. If the clutch and flywheel look decent or new you can run them. I know I have before on dedicated trail rigs. But on something that will be used for daily driving it is just best to replace the clutch and resurface the flywheel now while everything is apart.
Oh and while your at the truck before it gets crushed get the vin and year and note if it is anything Wierd like a dually, 350, or bread truck. Not doing this may have you kicking yourself later. It also makes it easier to just say you want a clutch for a 87 Chevy 2500 5.7 then explaining to the kid what kind of clutch numbers you need. Although I would still look into cross referencing clutch numbers to make sure the kid is selling you the correct part insted of finding out back at the house.
 

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I have not tried to mount a 465 directly up to the 4401. It would require some type of adapter and I try to avoid adapters like the plague. If you find a 4wd 465 it will most likely be mated to a 205 with a small adapter which is only a few inches shorter then if you went with a divorced setup.
I have a 69cj5 right now that I had a 465,dana18/20 hybrid case, twin sticked, tara low, with warn overdrive built for. I do not know what engine i want to use on it just yet.. The combination is super tight because that's what I needed with the short wheelbase. I put that project on hold to build a buggy which is rear engine383, 465, brownie(divorced), custom transfer case(divorced) to custom 2.5 tons. This will be super easy to work on with no adapters and I should not need to baby it like I will with the cj5.

Adapters severely limit your choices later on. If everything is not perfect that adapter is nothing more then a fancy piece of scrap. I am not saying do not try it. Do what works for you. Anything is possible with enough cash and knowledge tossed at it. I just like things simple(and cheap).
 

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Discussion Starter · #14 ·
Yeah. I want to be as simple and cheap(while using the best parts I can get) I want to keep the price down as I'm still I'm college so I don't want to drop a small fortune into it. I just want a basic swap that can be upgraded when I want to down the road. When I get out of college I might get an efi system, but I'm not sure. As of now I'm going with a sm465. (The easiest tcase to match up) and still looking for a strong driveshaft.
 

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You could do a little work on the heads, clean up the bowls, smooth over the exhaust ports. Get a solid lift cam like the Comp Cams XS256S .527/.532 lift and 218/224 duration. This should give you about 550 lbs of torque.
 

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Discussion Starter · #16 ·
I found this for $250
muncie sm465 4 speed transmission with granny first gear. np205 gear to gear transfer case and Chevy v8 bell housing.
Great for off road truck or mud truck very low geared and strong as hell.
$250 obo cash
Would that be desireable?
 
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