TwitchZ28

Hey guys

Lately i've been putting serious though into getting rid of my 4th gen(02 z28) and doing a semi resto-mod 3rd gen. I want to do something a little bit different though that isn't just your standard ls or big block 3rd gen with a big motor, beefy drivetrain, tall rear end gear, and fat tires. I think I would rather take a car in the direction of a GT car(grand touring). I just want to throw this out there and see what ideas or suggestions you fellas may have or encouragement/discouragement for these ideas. If I undertake this it is going to take me years to complete because I am not at a point in life with a ton of disposable income but should be in the next 4-6 years hopefully.

So the overall theme for the car is quality. Great paint, nice ride, decent handling, comfortable seats, a mild motor with good torque and decent mileage, etc. Here is sort of a baseline of ideas.

Engine- The idea here is to make something that 1. Sounds fantastic 2. Puts down reasonable horsepower as not to be embarrassed on the street 3. Maintains near stock or stock drive-ability and throttle response. This means a broad flat torque curve. 4. Is exceptionally reliable. 5. Maintains reasonable all around gas mileage if it isn't being beat on. This means fuel injection...namely an ls based power plant, a nice overdrive trans, and something like 3.73 rear gearing.

Engine:
Iron LS 5.3/6.0/6.2 whatever I find the best deal on
Mild rebuild with a stock cam, stock heads, just nice new possibly forged internals
Twin Screw supercharger(kenne bell, whipple, maggy)

Exhaust- The idea here is to have something with great sound but not crazy volume that could get annoying on trip. The sound must be clean, mean, and drone free.

Exhaust:
Long tubes will but used for performance and sound reasons.
2.5 or 3" true duals with an h pipe setup for the best sound
high flow cats to clean the sound up a bit and make the eco hippy in me happy
something like sweet thunder or 10-series flowmaster mufflers

Transmission - The idea here is to have something that is 1. Fun 2. Durable 3. Overdrive(for that fuel economy reason) and 4. Comfortable. This means no super short throws or notchy shifters. To me the best shifter mechanism I have used was in a 2013 Camaro ss with the factory hurst option. Direct and precise without being notchy or too short.

Transmission:
Mild build T56 or a TKO-600 here. I don't know much about the new TR6060 units in the 5th gens. This may also be an option
Clutch would be something that isn't too stiff but is stout enough to be reliable behind that engine.

Rear end - The idea here isn't maximum acceleration or fuel economy. It's a balance of the 2. For this I feel(transmission gearing dependent) that a 3.73 ring and pinion would be the best balance.

Rear end:
12 bolt or a 9 inch...either would be fine really I think.

Suspension - The idea here isn't to make a car that transfers weight really well with drag shocks, or a car that can corner carve with exotics. It's to provide a comfortable, stable, confidence inspiring ride. The 3rd gens aren't bad handling cars from the factory but could use some chassis stiffening and body roll control if I remember correctly(It's been a few years since I was behind the wheel of a 3rd gen)

Suspension:
Here I honestly don't know what components I would plan to use. This may be one of the last areas on the car to get real attention besides replacement of bad parts, bushings, and the alignment. With the shocks and bushings replaced the car should have a decent ride that I could live with for quite a while.
Strut tower brace
Weld In SFC's

Body - The idea here is to have a car that I find visually appealing. Some thirdgens are down right arousing and I love that about them. I haven't completely decided on a color yet but since I don't plan to strip the car for restoration I will be buying a car in a color I like so the door jams and under the hood match after paint restoration. I dig the maroon, black, red, and sometimes white cars.

The wheels will be 16in or 17in with 275/40s all the way around(40 series to maintain decent ride). I like the fikse fm5s quite a bit but they are pricey. Wheels to be selected later.

The hood will be a 2in cowl hood and there may or may not be stripes done depending on color choice.

Interior - The idea here is comfort, modernization, and visual appeal. I've seen where people have done 04-06 GTO seats in a thirdgen and I have considered doing that but re-upholstering them to just have GT stitched into them or maybe Iroc-GT. This seems like a large investment though and aftermarket seats may be a better route. Something with GTO seat characteristics though so lots of padding and good support.

Hopefully I will find a car with carmine red interior. I can't explain why I love that porno red interior but I do haha. The dash will get vinyl wrapped since it's surely all cracked to hell and the rest of the interior will be cleaned significantly and re-dyed to match factory spec.

The gauge setup will most likely be a large white face speedo and tach in the factory locations(as long as I get a car with the circular gauges) as well as white face fuel and volts in the factory locations as well. I haven't decided on doing a pillar pod for the rest or mounting them above the stereo.

The steering wheel will be something in all black with a nice fat leather grip and nice appearance. Maybe a flat bottom.

The center console may also be vinyl wrapped like the dash but not dyed.





I am going to take a break from writing this for now and come back later to edit. Thanks for taking the time to read through this novel and I appreciate any and all feedback.

-Mitch

InfernalVortex

iTrader: (4)

1. The Gen III+ bottom ends are known to be very, very, VERY good. No need to upgrade it if you're not broke if you're using stock heads/cam. They're known to be good up to 1000hp according to some, and above 6000 RPM is fine with some upgraded rod bolts. So no need to spend money there, especially at near stock levels. Those engines are designed very well.

2. If you want long tubes, you owe it to yourself to get a T56 (no T5) and make a double hump crossmember. It's the key to getting a low stance with long tubes. There is not much room under the car, but the main problem is the exhaust has to go under the crossmember, there's no where else for it to go. So a double-hump crossmember will solve that problem and allow you to get the GT stance. Doing it with duals is complicated, but that'll be your problem. You'll have to find room up the driveshaft tunnel to fit both pipes and then get them both over the axle, but there are ways to do it. If you're not too attached to duals, you can do a nice 3, 3.5, or 4 inch single exhaust and if you're crazy, I always thought it would be cool to split them after the axle and run dual mufflers pointed straight out the back (like a C4 vette). But to make it symmetrical with the car's centerline, you'll need to notch the trunk pan. Just one of those things. Otherwise there may be some single-in, dual-out mufflers for a 3.5-4 inch pipe, but the selection is limited. With a big single pipe you'll need a big muffler to quiet it down, too.

3. Stripes are easy to get very very, very wrong on these cars. I see VERY, VERY few that look good. Dont paint them on the roof or on the bumper cover. They need to be decklid/hood stripes only, and I find stripes on cowls dont look that great. There are a few guys here who have stripes on cowls and they can make them work since their cars are very nice, but the lines of our cars dont lend themselves to traditional stripes. IF you're going Gen III/IV engine, I would suggest staying with a flat good and running 92-style heritage stripes. They really do look great on these cars.

4. There's a reason all the dashpads are black. It significantly reduces glare on the windshield. When these cars were first made they had one of hte steepest windshield angles out there, and with black the glare is greatly reduced. With red you may not be able to see well. I would suggest leaving the dashpad/console/dash black, which is what the factory did, and mostly for that reason.

Anyway, I think we need more pro-touring style builds of these cars, they're raelly well suited to it as long as you dont modify the body lines too much. They handle really, really well (as well or better than 4th gens given equial prep) and can take any drivetrain combo you can throw at it. They do ride relatively harshly compared to a 4th gen of the same effective spring rates, they're flimsy and need subframe connectors, there are lots of squeaks and rattles, and a few of the factory parts will drive you crazy. Things like the hatch pull down and window motors and the tiny tiny tiny front brakes. There are many affordable brake retrofit packages available, though. Also, for the record, if you do a 5.3/5.7/6.0 swap, the car will be probably 300-500 lbs lighter than your 4th gen. Thats one of the big advantages over a 4th gen, that and the drivetrain versatility.

Some cars you may want to take inspiration from:



Crazy camaro from Japan showing hte unique charm the 91-92 cars have. The Z28s of these two years have VERY low production numbers so if you find a mint, low mile one you may want to preserve it rather than mod it. Dont ask about the hoods. Seriously. Just don't.







BADNBLK


http://www.hotrod.com/featuredvehicl...aro_third_gen/

If you want something more street-oriented (GT builds are inherently track car inspired, even though they're not as ***** to the wall, which is why I listed those.)

And I love this guy's car. Terrible smogger crate engine, but it goes to show you how well these cars do everything else:


Make sure you look through all the COTM's, there have been some REALLY nice ones.

TwitchZ28

Thanks for the feedback infernalvortex. Let me take a second to address some of your concerns.

1. A T5 was never on the table from the start haha. If it can't handle a factory 350tpi it's not going behind a blown ls.
2. I do remember seeing people do the double hump for the exhaust and it may be the route I have to take. I am pretty set on duals because I just can't find a y-pipe setup with ls based motors that I like. I've got true duals on my 02 and like the sound much more than any y setups I have heard in person. I haven't decided for sure on long tubes vs ls manifolds(of which some are actually pretty good).
3. I also share the opinion of striping being really hard to do and that's why i said that I MAY do stripes. It's only if I find a color combination and stripe style I really like. It will most likely not be striped and if it is it will be vinyl.
4. I forgot the dashpads were black. It will remain black.
5. I've seen all those cars and that video before. Good stuff. I draw a lot of inspiration from this video. I believe the guys username on here was yahtzee

cosmick

TKO600 tq rating is 600, T56 is 450, TR6060 is 430, T56 Magnum is 700. RSG is 1000. Choose accordingly.

TwitchZ28

The TKO-600 also isn't much larger than a t5 in overall size am I correct?

NagleMac

iTrader: (1)

For good handling WS6 sway bars (or aftermarket if budget allows) along with the bushings and endlinks, and some lowering springs with shocks and struts. A lot of people like the Koni Yellows, I personally went with Lakewood drag shocks and love the way it rides. Replacing bushings is obviously a good thing but using polybushings (easier to get than stock rubbers, also last as long as the car will) is going to stiffen up the ride a little bit, losing some comfort.

InfernalVortex

iTrader: (4)

TKO's are tough transmissions, but they're not factory, which leads to a few strange glitches and conversion issues. In some ways a T56 is actually a lot easier (Especially for an LS platform) because there are so many similarities between 3rd and 4th gen cars behind the firewall. The mount moves back 2 inches, but other than that you should be able to use most if not all factory parts to make the system work. Also the other main dig against TKO's is the gear ratios are a little odd. Make sure if you go that route compare the gear ratios to something you're familiar with (T56?) and see how they differ. One of the TKO's is notoriously terrible for track day use due to the strange gear ratios if I remember right... Also, the T56 is a very good, strong design, or they wouldnt have used it in so many powerful cars for so many years. The parts are out there to beef them up and if you want you can even get OEM parts that will support much higher loads, hence you may see a few "Viper spec" (marketing jargon, but the parts to upgrade to viper torque capacity levels are definitely out there and there are people who do the work to do that) T56's for GM V8s. The T56 is a very common, modern manual transmission used in a lot of modern performance cars. I think it's smart to go with, when you can, parts that are OEM because they're designed to outlast warranties and be reliable.

And about sway bars, crazy as it sounds, a lot of the road race/track car guys are running smaller and smaller rear sway bars. I know some that dont run any rear sway bar at all. They use the biggest front bars they can find and no rear bar. The drag race guys go completely the opposite. So keep that in mind, just food for thought. A happy compromise is a factory combination, but I just thought that was interesting.

TwitchZ28

Ok I see where you are coming from. I wasn't aware of any those difficulties with the TKO's. It just seemed to me that getting a built t56 may be more expensive ard larger but you're correct to say it would be an easier install. I am also pretty comfortable with t56 ratios as I have driven plenty over the years. I haven't yet looked up the tko's.

I really don't plan on doing anything wild with the suspension. It will remain close to factory. More chassis stiffening, new rubber bushings where needed, replace worn parts, lower it very slightly, and go.