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OK, So I think it's time I finally write this story haha. I bought my car about 4 years ago off craigslist. It was an original 1986 sport coupe, total base model with a 2.8, auto trans, 14 inch steelies, but with power windows.
The reason for me finding this car in particular was the fact that my previous build was also an 86 sport coupe. Both cars were the same color, with the exception of my first one being a 305 carb'd car. They both even had the original 14 inch steelies with chrome trim rings.
Anyway when I came across it on craigslist, I had to have it. It seemed like a sign from the gods giving me a second chance! Some of you may recall me having a half assed build thread on that car.. It's probably still floating around on here somewhere. Basically what it came down to was the car was pulled too far apart, and I just wanted to find a running car that I can enjoy driving as I built it.
Also being it was a 6 cylinder base car, it was way cheaper than what Iroc's or V8's were going for around here. And it was pretty clean. I paid 1,800.00 plus tow for it, not sure how many owners it previously had, and I still never checked to this day. I wasn't crazy about the price, I was hoping I could of got it for less, but being it was literally almost the same car as my last one, I didn't mind too much.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Here’s a few shots of my first Sport Coupe. This was a 305 auto car with crank windows. Anyway, the 305 started knocking right when I was getting ready to get some plates for it, thus initiating the tear down. Unfortunatly I lost interest and just wanted something I could drive!
So after I gave up on that car, I parted out whatever I could, and saved a bunch of good bit’s for my next one. I picked this one up maybe a year, to a year and a half later. You can see it’s a little less crusty haha.
That second to last photo is from the craigslist posting :P
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Matt, been following you for a while on instagram. Just starting a very similar build myself.. 85 sport coupe, manual. Putting in a 5.3 and (probably) T56. Are you going to be posting build pics? Follow me on IG austin_r_wilson
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by AustinW13
Matt, been following you for a while on instagram. Just starting a very similar build myself.. 85 sport coupe, manual. Putting in a 5.3 and (probably) T56. Are you going to be posting build pics? Follow me on IG austin_r_wilson
Cool, yea I have quite a few pics so I will be posting them. Just was busy finishing up the new video, so I didn’t have time to post some more. More progress will be posted soon.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So I had the car towed from Jersey back to my house, about 25 miles. First order of business was to get the 2.8 running right. It had a few issues, the biggest thing was a bad lean pop/backfire out of the intake while under load. It also had some oil leaks that needed to be repaired.
I posted the backfire issue on here, and ran through a number of things before I finally found the issue. First thing I tackled was the oil leak.I changed the valve cover gaskets, as well as new intake gaskets. I also adjusted the valves while I was in there, thinking maybe the lash was a bit too tight and holding some valves open. I also discovered the distributor was shot, so I picked up a new one along with some plugs and wires. I set the timing and went for a drive..
So during the test drive I noticed the car ran better, it idled smoother.... But it was still backfiring out of the intake under any acceleration. So I then swapped out the mass air flow sensor, but that didn't help either. I also checked the fuel pressure and it was OK. So for my next trick, I decided to replace the timing chain. I figured maybe its stretched? I mean it was a 27 year old car with who knows how many miles... The ODO read 89xxx, but who knows how many times it rolled over.
So I started replacing the timing chain and this is what I found...
Yea, I think it still had a few more miles in it right? While I was in there I also replaced the oil pan gasket and threw on a new water pump. So I got it back together thinking that this HAD to be the problem.. yea it wasn't.
Although the car still ran a little bit better, and the throttle response was soooo much better, it still gave off a few backfire pops out of the intake while accelerating.. Anyway a few users suggested that the injectors are most likely clogged, so I bought a low mile set off a fellow member, and it was fixed! NO MORE INTAKE BACKFIRES!! It had plenty of power.... for a 27 year old 6 cylinder with 120 something hp when new..
So now that the car was finally drive-able, I started doing some other mods...
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
First thing I did was clean up the old paint. Clay barred and buffed out the whole car. Even though the clear was hazy, and flaking off a bit on the back, It came out pretty good and I was happy with it. I also swapped on a set of GTA wheels with brand new tires I had sitting in my basement. I picked up these wheels for my last car, then re-finished them myself. When I picked them up the paint was faded and corroded plus the clear was peeling really badly around the lip. I just stripped them down and polished the lip up with no clear, then sprayed them with black rattle can gloss.
I gave the WS6 center caps a custom touch as well:
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Haha you probably also noticed in some of the pics, the rear wheels are tucked, and some they stick out. After I put the wheels on I ending up swapping in a 97 Z28 rear. Now I had rear disks, posi, but the rear wheels were now sitting farther out. This kind of annoyed me, but I ran it anyway. I had plans on swapping the wheels out later on.
Old rear out:
4th gen rear painted and ready to go in the car:
4th gen rear :
3rd gen rear:
Oh yea I also swapped out the stock sport coupe lights for z28 lights.. I picked these up for the last car as well.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
I should also note that after swapping in the 4th gen rear, I picked up some hawks parking brake cables, so the parking brake works perfectly with the new rear. I probably drove the car with the 2.8 for maybe 2 months before disaster struck...
One day I was driving over to jersey to pick up some tires for work. Once I arrived I noticed a slight knocking noise while the engine was idling. I instantly new it was a rod knock. I literally said to myself out loud right there, yessss time to swap in a 350!
So I BARELY got the car home after picking up those tires. I had to stop off at my house to switch cars because it wasn’t going to make it back to my job. The knocking got louder and louder, and the car eventually starting turning off a few blocks from my house. After continually starting it back up, I got it in the driveway and turned it off. Yea that was all she wrote.. tried to restart it and nothing. Locked up tight.. So out the 2.8 and auto came, and I planned on installing a carb’d 350 with a manual.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
I also went and replaced most of the suspension as well. I don’t really have any pics on this, but it was all factory replacement stuff. I did this during the 2 month period that I was driving the car before the motor blew. New inner and outer tie rods, center link, idler arm, lower ball joints, and kyb shocks.
I also went to a junkyard and picked up a close ratio ws6 steering box. I’m still running the same box in my car today. In addition to that I scored some free parts from another TGO member, one of those being a 34mm front sway bar. I installed that the same time as the steering box.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So I decided on a carb'd 350 and 6 speed t-56 to replace the 2.8 auto. I had a friend with a tired 350 short block in his garage, so I picked that up from him for 100 bucks. Being the car was an auto, I knew I had some work to do. I knew I needed to cut a hole in the tunnel for the shifter, as well as the firewall for the clutch master. In addition to that I had to bypass the neutral safety switch so the car could crank. To figure most of this stuff out I spent some time scouring this site.
I picked up my 97,xxx mile LT1 t-56 off craigslist for 1000 bucks.
For the motor I decided to do a stock bottom end rebuild with some good heads, intake, and a decent cam. I was aiming for around 400 crank hp. This was my first time rebuilding an engine, so I did a lot of research to make sure I didn't **** anything up lmao. I pulled the block apart, kept all the pistons and caps in order, sent the block out to get cleaned and new freeze plugs, and cam bearings installed. I also had the crank measured and polished.
When I got the block back, the first thing I did was give it a nice coat of paint. I later changed my mind and painted it again in black.
I went on rockauto and picked up some piston rings, rod bearings, and crank bearings. The shop told me I needed stock size rings, the block was never bored, and it had no ridge so I was good to go. I ended up using a dingle berry hone, but I wish I would of had it honed professionally...
I used plasti-gauge to check all the tolerances, and I have to say, I got everything just about perfect. Even picked up a dial indicator and checked crank end play. That was also within spec.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Bottom end back together!
And now it's black:
I also bounced around between timing covers. While searching online I realized that with an aftermarket cam, I needed a cam button. I ended up swapping over to an aluminum cover with a nylon cam button:
I ended up going with a comp XR276HR cam and Dart Aluminum heads. I believe the intake was an Edlebrock RPM airgap, with a 750CFM carb, but I'm not 100% on this... its been a while. I also went with a retrofit roller lifter kit being I had a non roller block, I believe it was a Howard Cams kit.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Also that black 700-r4 you see sitting on the floor beside the block was the trans that I saved from the first sport coupe. I ended up rebuilding it in the basement, testing it on the trans dyno at school, and selling it on craigslist. I have a few pics of that:
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So my motor was finished and ready to go in the car! Before dropping it in, I decided to clean up the engine bay and paint it so it would match the original color whenever I had the car painted.
Just a little tip, tin foil works great to cover up weird shaped parts that you don’t want to get paint on..
I had my color code mixed up in rattle cans at the local paint store.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
That’s a roller block. Has the holes for the cam retainer plate and the bosses for the lifter hold down bolts although those aren’t tapped. Perhaps it was from a truck that wasn’t running a roller cam.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by Ty92Z
That’s a roller block. Has the holes for the cam retainer plate and the bosses for the lifter hold down bolts although those aren’t tapped. Perhaps it was from a truck that wasn’t running a roller cam.
Yes you’re right. I contemplated drilling and tapping the block for the spider, but it was just easier to get the retrofit lifters.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by LsxMatt
OK, So I think it's time I finally write this story haha. I bought my car about 4 years ago off craigslist. It was an original 1986 sport coupe, total base model with a 2.8, auto trans, 14 inch steelies, but with power windows.
The reason for me finding this car in particular was the fact that my previous build was also an 86 sport coupe. Both cars were the same color, with the exception of my first one being a 305 carb'd car. They both even had the original 14 inch steelies with chrome trim rings.
Anyway when I came across it on craigslist, I had to have it. It seemed like a sign from the gods giving me a second chance! Some of you may recall me having a half assed build thread on that car.. It's probably still floating around on here somewhere. Basically what it came down to was the car was pulled too far apart, and I just wanted to find a running car that I can enjoy driving as I built it.
Also being it was a 6 cylinder base car, it was way cheaper than what Iroc's or V8's were going for around here. And it was pretty clean. I paid 1,800.00 plus tow for it, not sure how many owners it previously had, and I still never checked to this day. I wasn't crazy about the price, I was hoping I could of got it for less, but being it was literally almost the same car as my last one, I didn't mind too much.
hey man I been subbed to for a while! I got a coupe too but I'm desperate to put on some ground effects ! If you don't mind me asking where did you get your ground effects from?
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by Ericklsx
hey man I been subbed to for a while! I got a coupe too but I'm desperate to put on some ground effects ! If you don't mind me asking where did you get your ground effects from?
I picked up a 92 roller car. That will be coming up soon haha.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by QwkTrip
Nah, man, learn to embrace the base model. They are so cool when you give it some power and get the look right.
I do agree with this! When I was first putting the car together, I thought it was going to be a street/strip car. Sport coupe's looking amazing with a drag setup. For example, Matt Walter's car:
But after I went LS and swapped to bigger brakes, I then needed bigger wheels to clear the brakes, and eventually I knew I wanted to get into auto x. And IMO Sport coupe's start to look kind of weird with anything bigger than a 17 inch wheel.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
I originally installed 4th gen pedals for the clutch, but I later swapped them out after developing a leak from the master cylinder shaft seal. I believe this was due to firewall flex. The third gen pedals had better bracing where they met the master cylinder, and after installing them along with a new master, I never had another problem.
I cut my hole in the firewall by using the cutouts in the firewall insulation. I just marked though the insulation cutouts with a sharpie and went to town with a dremel. At the time I was using 4th gen LT1 clutch hydraulics.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Just curious how did you set cam endplay with the button.
It doesn’t look like there is a hole in the cover to use a dial indicator.
With the factory roller you can use a cam plate in the front of the block. I don’t think the retrofit cam allows for this it doesn’t have the correct step machines into it.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by Tuned Performance
Just curious how did you set cam endplay with the button.
It doesn’t look like there is a hole in the cover to use a dial indicator.
With the factory roller you can use a cam plate in the front of the block. I don’t think the retrofit cam allows for this it doesn’t have the correct step machines into it.
Thats a good question haha. I don’t remember exactly how I did it, but I do remember I filed the button down a little at a time, until the cover with gasket can just be secured. I then went either through a lifter hole or through the bottom of the block and set the indicator on a cam lobe. I don’t remember if I put the cam in before the bottom end or after.. I then shifted the cam forward with a large flathead, measuring the amount of endplay, and pulled the cover on and off shaving a little bit more off the button until I got the play within spec.
Lmao yea a cover with a hole would of been alot easier. I was new to small blocks back then, literallly the first engine I ever pulled any internals out of. The whole thing was a learning experience.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So my 350 was in, and I was ready to go. The motor started right up, and oil pressure was fantastic! It idled beautifully and had a really nice lope to the idle. A local TGO member came by and helped me out with setting the fuel and timing. For a clutch I ended up going with a stock 4th gen unit. I reused my 3rd gen driveshaft. I finally ended up picking up a set of different wheels. I bought a set of staggered c5 vette wheels from a guy on craigslist. 17x8.5 on the front and 18x9.5 on the rear. I then picked up a pair of 2 inch wheel spacers and got the wheels mounted up. As you already know, being I had a 4th gen rear, no spacers were needed on the rear.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Around the same time as I did the wheels, I also went and installed a set of UMI Performance weld in subframe connectors. After this I decided that I was tired of faded gray paint, and ended up spraying the car with flat black epoxy primer. I don’t have any photos of the prep, but I sanded the car down with an electric DA, and any chips or rust spots I took down to bare metal. I used a 12 gallon compressor and harbor freight spray gun. Being this was only temporary, I didnt repair any dings or dents. This was the result:
Also for my exhaust I went with a set of shorty headers and an off road hedman Y pipe. I ran a stainless magnaflow catback. I wish I had a sound clip of the motor, it idled meeeaan!
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Notice my plate says LSX... Well I don't have too many pics of the car with the 350 in it.. because I only had that motor in the car for maybe a month or so...
So here's the story behind that. What ended up happening initially was when I first started up the motor, everything seemed great. It idled perfect, oil pressure was perfect, no tapping, ticking or any weird noises at all. I set the timing, base tuned the carb and set off for a test drive.
Annnnd, it was slow as ****! After messing around with swapping carbs and adjusting timing, the issue ended up being a crappy harmonic balancer. The aftermarket ebay balancer had the timing marks about 8 degrees off! I confirmed this by finding TDC with a piston top, marking the balancer, and resetting the timing. After this the car flew!
I had the carb re-adjusted and the motor timed once again by that fellow TGO member, who's user name I cannot remember . The only issue after that was that I started seeing some blue smoke....****.
So light blue smoke started appearing out the exhaust. Even though I kept easy on the motor, did my best to seat the rings, it just kept getting worse. Power was dropping off as well. A cylinder leak down tested revealed 40 percent leak down on all cylinders through the rings!
Now there's really only one thing that I can think of that went wrong.. We'll I did measure ring end gap on all rings during assembly, and everything was perfect, didn't even need to file any. The only thing I remember doing was ordering moly rings instead of OE cast iron rings. However I did de-glaze the block with a 180 grit ball hone. Now I was thinking this was too coarse of a grit for moly rings, thus causing them not seat and the giant smoke show.
Either way, I'm sure if I had the machine shop hone the block for me, I probably would of been alright. But whatever, you live and learn! Plus now I had the perfect excuse to do what I thought I wouldn't have the money or know how to do... An ls swap!
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So after I decided on doing an ls swap, I had to decide what motor I was going to choose. I knew I wasn't going to with an actual LS1 due to price. I ended up choosing a 5.3.. Junkyard 5.3's with intake, injectors, and sensors went for around 600-1200 bucks depending on mileage. 6.0's and LS1's went for anywhere between 1300-3000 with the mileage being anywhere between 80,000 and 200,000.
I ended up finding a 5.3 long block on craigslist for 300.00 with 87,000 miles. The motor came out of an early 2000's silverado. The previous owner had it sitting on a engine stand in his for garage for 3 years, after pulling it out of his truck for a 6.0. I was told there was nothing wrong with it. For 300 bucks, I took his word for it.. Unfortunately being he swapped motors, my 5.3 came with no sensors, intake, accessories, or anything! Not even rockers or valve covers.. Just heads, cam, and complete bottom end.
So after picking up the motor, I got it to a friend's garage, and decided what I wanted to do with it.I pulled off the heads to inspect the cylinders and replace the head gaskets. Everything looked perfect! I pulled out the cam as well, and put in an LS1 cam from a 2002 Camaro, along with an LS2 timing chain. I then ordered valve covers, rockers, and push rods. I got most of the stuff used between TGO and Ls1tech. I also picked up an LS6 intake along with a cable driven Camaro throttle body, and LS1 Camaro exhaust manifolds.
I knew I wanted A/C so I picked up all new accessories and an A/C compressor through rockauto. I also new I was going to run an f-body pcm and harness, so I ordered all f-body coils and sensors. My accessory drive was also 4th gen f-body style. I got my injectors from the same person I bought my intake manifold from, they were 28lb LS1 injectors. I then picked up a "muscle car" ls oil pan from Jegs, which I will later realize hung ridiculously low under the k member... I then picked up a used f body pan from Ls1tech.
Here's the block with heads removed, fresh paint, and the low hanging oil pan.
All ready to go in the car! I later picked up egr block off plates.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So after I had the motor all ready to go in the car, I started prepping the car. Now I did the actually swap in a friend's garage, but before I had it towed there, I did most of the other work in my driveway. I removed the K member, notched and plated for the A/C compressor and oil pan. I also installed my UMI motor mount adapters when the k member was out of the car. I then dropped down the tank and installed a walbro 255 pump, along with a new sender. At the same time I ran all new 3/8 fuel line, and installed a corvette filter/regulator. All my connections from hardline to pump, and hardline to rail, was with AN fittings and braided hose. No cut corners here!
Now as you know I had an LT1 T-56. This wasn't going to work with my LS motor without a few modifications. I went on ebay and picked up an LS input shaft, along with an LS bell housing and front cover. All these parts cost me around 600 bucks new. LS1 m6's were going for 1500-2000 on craigslist, so being I paid 1000.00 for my LT1 trans, this was reasonable to me.
Here's the new sending unit installed. I ended up flaring the ends of the supply and return lines where the stock rubber hoses connected. I then used that to screw on AN fittings and hoses to connect to the fuel lines on the car.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Nice car (I flipped ahead and already read the last page of book).
Again, I know I'm jumping ahead, but why do you have a FAST 102R intake on a 5.3L? That intake is killing your low and mid-range. I would guess you would be better off with a stock truck manifold since you've got a large cowl hood. Even an LS3 manifold might be an improvement.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by QwkTrip
Nice car (I flipped ahead and already read the last page of book).
Again, I know I'm jumping ahead, but why do you have a FAST 102R intake on a 5.3L? That intake is killing your low and mid-range. I would guess you would be better off with a stock truck manifold since you've got a large cowl hood. Even an LS3 manifold might be an improvement.
Hmm honestly I never really thought about it until recently. When I was putting the motor together I figured more air flow=more power. Then I started thinking about it while I was helping my friend with his 5.3 caprice build. We kept the intake on his car because it clears the hood, and it does flow very well. The main reason I shyed away from the truck manifold was because of looks...Then I wanted to upgrade from the Ls6, and I figured the fast would be the next step. I didn’t go with an Ls3 because I have cathedral port heads. Also the car pulls hard, even down low, so I didn’t even second guess the Fast, plus I felt a noticeable power bump when I swapped the Ls6 for it.
I do plan on selling the Fast though, I already have a buyer for it. I didn’t think an ls3 intake would fit, doesn’t it only fit square port heads?
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Sorry, I saw a "102R" and assumed you had rectangle port heads. Didn't realize they make it now for cathedral port heads. My info might be very dated but I thought the FAST 90 or 92 was the hot ticket for cathedral port engines of that size? (that's a question, not a statement)
You might be able to find a dyno curve with FAST 102R making more peak power but I'll bet drivability suffers (throttle response, low- and mid-range torque) and the car is slower in the real world around town. The right answer is probably whichever manifold delivers more area under the torque curve in the rpm range where you operate. You can feel a 10 lb-ft change by seat of the pants.
Higher flow numbers on a bench isn't necessarily better. It's all about accentuating what the engine wants and when it wants it, so as to improve cylinder fill and exhaust scavenging. The cam valve events and intake manifold need to compliment each other to produce favorable results in the rpm band where you want to make torque. Getting it right sometimes doesn't net you more peak horsepower, but it will give you a broader torque curve and make the car quicker with better drivability.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
So after my fuel system was finished, I was ready to put the engine in the car. My motor didn't come with an ECU or harness, so i picked up a pre-flashed ECU off ebay for about 200 bucks. It was a red/blue 2002 Camaro computer. I had the seller remove vats, evap, and the rear O2 sensors. I also had him set the fan temp to 190 degrees. For the harness I went with a PSI conversion unit. For a little less than 600 shipped, it was a great deal, all plug and play and pre-loomed. I drilled the hole for the harness to pass through under the A/C box, right above the frame rail. I set the computer in the factory location.
After the hole was made in the firewall for the harness, I installed the clutch and bell housing onto the motor and dropped it in. Everything went in without a hitch! I finished converting the trans to work with the ls motor a few days later, then installed that as well. Everything lined up beautifully! The stock driveshaft and torque arm fit as well. I wired the harness up to the factory pcm wires. I just probed each wire looking for constant cranking voltage for the injectors. I also just re-used the power wire going to the factory fuel pump, the harness came with a fuse and relay block. I soldered and heat shrinked everything together, grounded the harness to a cylinder head, and connected the power wires directly to the starter.
I then removed the fuel pump relay, filled the motor with oil, and cranked it over a few times to pre-oil everything. I then popped the relay back in and turned the key. Fuel pump primed, so I cranked it....
Annnnnd she started up instantly! I had a mechanical test gauge connected to the oil pressure sensor port. The motor had a solid 60 psi on start up! Literally first attempt, and she fired.. I was thrilled! I then ran the heater, and bled the cooling system. A few days later I picked up plates for the car and drove it home. Test drive was flawless, but LOUD. I brought the car to work a few days later and fabbed a custom y pipe for the f body manifolds. I bought the flanges off ebay and used a hawks y pipe to connect my piping from the manifolds to the rest of the exhaust.
These pics were taken the day after I drove it home. This is with the open y pipe, you can see I still didn't even have the evap block off plates installed yet!
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
For my fans I picked up a new set of LS1 Camaro fans. I bought a separate fan harness on ebay for 80 bucks. The PSI harness had the pcm fan wires routed into the engine bay, so I just tied the fan relay harness into that.
For A/C, even though I had the compressor on the motor, I didn't actually hook it up for a few months. I later picked up Hawks conversion hoses, and scoured between this site and Ls1tech for pcm pin outs. After finding the correct diagrams, I bought some extra pcm pins and wired the A/C circuit into the pcm. Once again I brought the car to work, then charged it up.. A/C and fans came right on, and blew ice cold!
For my intake I bought everything from intakehoses.com. I drove the car with the stock ls1 tune for a month or so before finally getting a dyno tune. The relatively stock 5.3 with the addition of the 02 ls1 cam, and Ls6 intake, and manifolds, made 308rwhp and 330rwtq on a dyno jet. I later switched over to ebay long-tube headers, but didn't put it back on the dyno. The tuner just made some adjustments for the long tubes.
Here's a screenshot I found from when it was at the tuner.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Matt,
On the UMI mounts, are you running them fully set back in the 1" position similar to the Hawks mount? I saw you were using an F-body oil pan in your video.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by Neil350
Matt,
On the UMI mounts, are you running them fully set back in the 1" position similar to the Hawks mount? I saw you were using an F-body oil pan in your video.
Neil
I actually looked at this the other day because someone on Instagram asked me about it. The Umi mounts I have are not adjustable. I think they changed the design somewhere along the line, because mine only have 3 or 4 single bolt holes. They’re not slotted either. You can kind of see in this shot I took the other day of my new steering shaft. Check out the mount.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
I see, they must be set back some in order to let the F-body oil pan clear? I was watching your youtube channel going over your build. It convinced me to stick with the stock K and notch for a 4th gen AC. Your build looks nice and factory, just really clean.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by Neil350
I see, they must be set back some in order to let the F-body oil pan clear? I was watching your youtube channel going over your build. It convinced me to stick with the stock K and notch for a 4th gen AC. Your build looks nice and factory, just really clean.
Thanks. Actually I had to notch the back of the k member to get the f body pan to clear. I guess the new style mounts eliminate this issue.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
Originally Posted by LsxMatt
Thanks. Actually I had to notch the back of the k member to get the f body pan to clear. I guess the new style mounts eliminate this issue.
My plan is to buy another stock K member if I can find one locally. Have it blasted, we have a spare '98 F-body long block with oil pan. So we'll drop that on there with the mounts, make what ever cuts for the ac compressor and notch in for the pan. Then have it powder coated. Looking at your set up, the lower mount AC is just such a cleaner route to go. I found this picture another member had posted, has a white 91 Z and his dad has a black 91-92 Z.
Re: From Base to Bad, My 86 Sport Coupe Build Thread.
OK, so after I went LS, I ran the car this way for maybe a year or so, then I started doing some more upgrades. I went ahead and swapped the 706 heads for a set of 799's that I picked up on eBay. I had a shop machine them down .030, and then installed a set of Brian Tooley valve springs, as well as upgrading the rockers with some Comp trunnion bearings. I also went with some LS9 head gaskets, ARP head studs, Comp hardened push rods, and to top it all off a stage 2 Tick Performance turbo cam. At the same time I sold my LS6 intake and picked up a cathedral port Fast 102 intake and eBay 102mm throttle body.
After this I decided to upgrade from the factory brakes to Cts-V brembo's. I picked the calipers up from a member on Ls1tech, along with the brackets and hoses. I modified and tapped the spindles myself. At the same time I realized that my 17 inch wheels were too small to clear the new brakes, so I picked up a fresh set of 18x9.5 C5 rim's off ebay. I'm running a 275/35/18 tire in the the front, and a 275/40/18 in the rear. I really don't have any pics of this work being done unfortunately, but here's some of the last shots I have of the car before the body work began...
Also I bounced back and forth between the Z28 grid tails, and the sport coupe lights. I put the sport coupe lights back in when I though I was gonna leave the car this way...
01-26-2018, 01:15 PM
but let's see where she'll go 
