Bajablazer85: 1985 Chevrolet S10 Blazer Build

Post #7 - Engine

I thought the brake kit was the fun part. I was kidding.

Teardown of the Camaro's 3.4L V6 began.

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The parts pile is accumulating...

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Short block achieved!

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My buddy came over to poke around and help out.

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Keeping my parts organized, I'd thank myself later.

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I found that everything internally is essentially brand new. At just over 100,000mi, I didn't drive the Camaro for long, but whoever owned it before me took very good care of it. With the exception of maybe not using the correct coolant ratio, as the water jackets seemed to have excessive rust.

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Off to the machine shop! Crank bearings would be polished, but kept at factory sizing. Cylinders were bored to 0.030" over. The heads were decked, and valves re seated. I had considered a port and polish and/or cam, but figured I could do that in the future if I wanted more power.

Supplementary build info: oil pan gremlins.

The difference between the 4x4 and 2x4 oil pans presents a challenge for packaging. The 2x4 oil pan on the 3.4L will hit the front differential. The seemingly obvious solution is to swap the pans, since the 2.8 and the 3.4 are the same engine architecture, right? Yes and no...

The below comparison shows the difference between 2.8 oil pan (left) and 3.4 oil pan (right) at the front seal. The difference is due to the design change from vee-belt to serpentine belt accessory drive.
This is explained more in depth here ----> http://www.s10forum.com/forum/f106/3-4-crate-engine-parts-list-and-info-428709/#post6768540.
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Here's where things get weird for me. I don't know how, but I was able to snag a 4x4 oil pan with the serpentine belt style front cover seal from this Blazer.....with a V-belt. A serpentine belt style front cover seal design shouldn't technically exist on a 4x4 vee-belt truck, except on the H/T 3.4 V6 offered from GM Performance parts, which is illegal for street use in Ca. For all intents and purposes, this is a unicorn.
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I'm not going to wonder too much about how I got what I needed, and not having to do a custom oil pan. But it just seemed like one hell of a lucky find for me.

While the motor is at the machine shop, I had some downtime. Did some washing and started rebuilding the 3.4L intake manifold. All 6 fuel injectors were sent to Doctor Injector for flow testing and rebuilding. Since new injectors run upwards of $60 a piece, this was dollars saved. And it turns out, they could very much use some TLC.

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And then my jewels arrived....
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Engine Continued

There's not too much to say about this next part, I'll let the pictures speak for themselves where applicable.

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The important notes:
The oil filter is mounted sideways and directly above the front diff carrier, factory. This creates oil changing experiences that are way more frustrating than they need to be, and a needlessly perma-greased front axle carrier. I have yet to figure out where I'll be mounting the remote filter, but I'll have to see how everything goes together. I realized the Camaro oil pickup would not work in the Blazer's deeper oil sump (because 4x4). Fortunately, the 2.8L oil pump and pickup bolt right into the 3.4L. You can see that I chose to go with MSD's coil packs right off the bat. I have previously used their product in cars I've owned in the past. Results were registered on the butt dyno. Worth it.

As with the removal, installation of the powertrain must be done in one piece.
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Being sure to have the wiring harness on before I will never have access to these bolts again!
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Wrapping the parts of the harness where heat will be present with heat reflective tape. This stuff is expensive, but the original Camaro's motor had it, so I obliged.
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Next, the shift linkage for the 4L60E. Again, because it's the same body as the original 700R4, the linkage is the same. However, the Camaro's 3.4L exhaust shield is slightly different from the 2.8L, requiring some persuasion from Mr Dremel. Here's the shift linkage in the "P" position
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And in the "1" position.
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Next steps include:
-Integrating Camaro ECU harness into Blazer chassis harness.
-Fuel system and emissions systems.
-Wrapping up the odds and ends on the braking system.
-Cooling system and putting the body back together.
-Odds and ends everywhere.

Thanks for watching!
 
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justcuz

Explorer
Occasionally I find a Bravada at Pick a Part. Since they are AWD the right side axle does not have the disconnect, it is an easy way to simplify your front drive axle and eliminate a possible problem.
My son had a GMC extracab in high school, we did the Bravada mod on the front axle and lifted it enough to run BFG 30x9.50-15 All Terrain tires on his stock aluminum wheels. His was new enough to have the TBI 4.3 engine in it. It was a great little truck. My Mom drives a 1997 S-10 Blazer. I really like these little trucks, they are under rated, but that's OK, you don't have to pay Toyota prices for used ones.
Ill be following along, keep up the good work!

Do the ZR1 rear springs give a lift or are the mounting points lower with longer factory shackles?
 
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I like this build thread and I will be following it. I had two different 87' Blazers when I was growing up. The 2.8 is definitely a dog. I actually rebuilt the engine in the second one I had and put in a stroker crank that made it a 3.1L. It helped. I may own another one someday and do just what you are doing. My first transmission rebuild did not goes as well as yours and I drove without reverse for two years. How you may ask? You just have to choose your parking places wisely. You also develop a strong left leg from pushing your truck out of level parking spaces!
 

Travelin _man

HEY HEY HOCKEYTOWN!!
Great build. Always had a soft spot for the S-10s/blazers and Sonoma/Jimmys with me being a ford guy lol. But this build is great and I cant wait to see more. If I may ask, I understand not running a 350 but why did you not go with a 4.3? Just curious.
 

justcuz

Explorer
He touched on the smog issue earlier in the thread. The 3.4 is the evolution of the 2.8, whereas the 4.3 while offered in later vehicles of the same platform may have required more modifications than he wanted to address. From a VIN standpoint, the engine family stays true to the VIN number. California has ever changing laws on engine swaps, so maybe this is the path of least resistance. I don't believe you can legally install a V8 in an S-10 chassis any longer in California, because it was never offered from the factory, unless it is a 5.3 LS engine which GM had certified in the state of California. A 1975 and older vehicle is not covered by any of these rules, 1976 and newer are all regulated by the Bureau of Automotive Repair. Rules are online.
 

Travelin _man

HEY HEY HOCKEYTOWN!!
He touched on the smog issue earlier in the thread. The 3.4 is the evolution of the 2.8, whereas the 4.3 while offered in later vehicles of the same platform may have required more modifications than he wanted to address. From a VIN standpoint, the engine family stays true to the VIN number. California has ever changing laws on engine swaps, so maybe this is the path of least resistance. I don't believe you can legally install a V8 in an S-10 chassis any longer in California, because it was never offered from the factory, unless it is a 5.3 LS engine which GM had certified in the state of California. A 1975 and older vehicle is not covered by any of these rules, 1976 and newer are all regulated by the Bureau of Automotive Repair. Rules are online.

Damn that sucks. I live in Michigan were we don't have any of those rules. We don't even have inspection or emission testing.
 

justcuz

Explorer
Lucky you! Your percentage of 1975 cars in Michigan probably number in the hundreds. When I spend time further south in Temperance and Lambertville it's rare to see many 20 year old cars unless they are yard ornaments.
 

Travelin _man

HEY HEY HOCKEYTOWN!!
Lucky you! Your percentage of 1975 cars in Michigan probably number in the hundreds. When I spend time further south in Temperance and Lambertville it's rare to see many 20 year old cars unless they are yard ornaments.

Oh yes. Being that we also have some of the biggest car shows of the year (Woodward dream cruise, Flints back to the bricks, Frankenmuth AutoFest and Autorama), Classic cars are everywhere, My dad alone has a 74 Corvette L82 4 speed car, 77 Mustang II mach I V8 that came from cali with 18k Original miles, a 76 Volarie Roadrunner drag car that was bought and owned by a Chrysler engineer and a 78 Fairmont. Its a blessing and a curse to live here because the love using salt on our roads and we have county road commission.
 

Buddha.

Finally in expo white.
You're not wrong about the poly bushings making a big difference. I've got them front and rear and with the big sway bars, and the factory HD springs it corners flat!
 

Clawhammer

Adventurer
I'm really digging your build here. You attention to detail is inspiring. The locker is going to help a lot, that's one area where GM really skimped on these things.

My first vehicle (and my first 4x4) was a '91 Blazer. I really abused that thing and took it some places it probably should not have gone but it never left me stranded. I really appreciated how the back seats folded flat for camping/sleeping in the truck and I think they're underappreciated as offroad vehicles.

When I was in college the tired 4.3 started acting up and honestly it probably needed a rebuild. I wanted to drop a 327 small block into it (always loved a 327, revs up faster than a 350, but just as reliable) but I couldn't talk my old man into it and, since I would have needed his help to make it happen at the time, I wound up selling it. I've always regretted that.

What are you thinking for suspension/lift/tires? I always wanted to run 32's on mine, but never got around to doing the lift needed for that.

You mentioned a remote oil filter. I did this on mine and it was a very smart move. If I can reminder right (been a few years), we mounted it on the top of the fender just low enough that the hood wouldn't hit it when it closed. I think we drilled a couple holes (or used some factory holes?) in the lip where the fender curved and went flat inside the engine compartment on the drivers side in front of the wheel well (if you follow my meaning there) and installed a little homemade(?) bracket that would hold the mount for the oil filter. Wish I could be more help, but it's been too long and I don't have any pictures. It was a good spot for it though, very easy to get to.

Best of luck with your build, can't wait to see how it all comes out!
 

justcuz

Explorer
My Moms 97 has the filter behind the skid plate up front, kind of a dumb place for a remote filter. I cant remember were it was on my sons GMC.
 

Buddha.

Finally in expo white.
On the second gens its behind that skidplate.(Most of those skidplates are plastic, I swapped in the aluminum version).

My mom had a '92 4.3 4x4. The filter was in the engine compartment, on the core support I think? That was her second S10 blazer. The first one was an '80's 2.8 2 door. We took that thing on a road trip back in '94. Had a wheel bearing go out just 30 miles away from home, dad fixed it in a parking lot and we kept going. I still remember getting passed by motorhomes and semi trucks on the steep grades when we got into the black hills.

I'm on my third S10 truck. I'd like this one better if it was a manual and had the g80 but it was cheap and rustfree.
 
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