1990 Iroc Convertible Build
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
1990 Iroc Convertible Build
Got this 1990 Iroc Convertible (305 auto) project that I have taken apart. Just a project we'll see how long it takes me to finish, if I can remember how to put it all back together. Initially I wanted to start by clearing the engine bay, getting it re-painted and go from there. After clearing the engine bay I towed it to the paint shop where I was given a price to paint the whole car that I thought was very reasonable for the work needed on the car. I took off all of the weather stripping, rubbers, window felts, etc. I told them to take off the fenders, nose, front windshield, lights, door locks, etc. I asked them to give me back a painted shell and to leave everything that was taken off, off for the exception of the completed shell. I hope it turns out good. They said two months before i get it back. Ill post pictures with progress.
I just drove to San Diego and picked up a complete running 1989 Iroc 5.7 engine from a shop for $300. Stock 305 runs really good but not gonna put it back in. I've read a lot on this site in regards to 5.7 builds. I've also got my hands on a set of new lowering springs and slightly used hotchkis traction bars (I think is what their called) for $150 for those pieces.
Ill post pictures.
I just drove to San Diego and picked up a complete running 1989 Iroc 5.7 engine from a shop for $300. Stock 305 runs really good but not gonna put it back in. I've read a lot on this site in regards to 5.7 builds. I've also got my hands on a set of new lowering springs and slightly used hotchkis traction bars (I think is what their called) for $150 for those pieces.
Ill post pictures.
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From: WINDSOR, CO
Car: 91 Z28, 87 SC, 90 IROC, 92 RS
Engine: LS1, 305 TPI, L98, NADA
Transmission: T56, 700r4's, and NADA
Axle/Gears: 3.89, 3.42, 3.23, NADA
Re: 1990 Iroc Convertible Build
Cool car man.
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Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
My car is not back for the autobody shop yet but I bought this T56. I got everything from the donor car 1994 Z28 except for the flywheel. He also threw in a new xtd clutch, pressure plate and throwout bearing for $550. I just had to help him take it out. This guy has the engine ,Lt1, from that car for sale for $500. That includes wire harness and computer. If you are interested pm me and I will give you his number. The WC T5 I bought is now for sale.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
It's been awhile but I just received the first picture from the body shop. He only sent one picture. It's still in the paint booth, he has to color sand it. Can't see much but it looks ok. I'll post more pictures when I get it.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
I'm going backwards here. This was a week ago as he was trying to finish the body work.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
Turned out ok,,,,. I like it. Gotta put it together now. The new emblems parking / marker lights make a difference. Got new glass with the correct weatherstrip.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
It's suppose to be the stock blue. Bodyman said he took the color code from the tag inside the center console.
Last edited by M3638; Dec 22, 2013 at 12:35 AM. Reason: Error
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
I'm looking at wheels and like these. KWC WHEELS. They make different sizes. I'd like 18x10 rears and 18x8 fronts.
Member
Joined: Feb 2008
Posts: 496
Likes: 1
From: Los Angeles (310)
Car: 89 IROC-VERT
Engine: TPI 305
Transmission: 700R4 Auto
Axle/Gears: 2.77
Re: 1990 Iroc Convertible Build
Looks 100% better! I see you went back to its original color, good choice man , blue on a 3rd gen is perfect. Keep the pics coming!!!
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Joined: Jan 2002
Posts: 482
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From: Michigan!
Engine: Vortec 4200 Inline 6 PT70 Turbo..
Transmission: 4L65E
Axle/Gears: 3.73
Re: 1990 Iroc Convertible Build
1 month to install 2 plastic tanks?!
Faster than I've worked..
Very nice project. Lowered, painted, 18's, T56, SuperRam'd 350... That's a recipe for happiness. 4.10 gears would make first gear useless on street tires but very fun! 3.42's would make it killer on gas though..
Faster than I've worked..

Very nice project. Lowered, painted, 18's, T56, SuperRam'd 350... That's a recipe for happiness. 4.10 gears would make first gear useless on street tires but very fun! 3.42's would make it killer on gas though..
Member
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Joined: Jan 2002
Posts: 482
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From: Michigan!
Engine: Vortec 4200 Inline 6 PT70 Turbo..
Transmission: 4L65E
Axle/Gears: 3.73
Re: 1990 Iroc Convertible Build
My 2 cents also... Do some subframe connectors before installing the exhaust system. Sometimes they can interfere with each other. They really really make the car work as it should AND they probably help the paint from cracking/flexing. They also make the car stronger in a crash, as i experienced in my 85 IROC. I cut them out of my totalled IROC and welded them into my convertible.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
Re: 1990 Iroc Convertible Build
"1 month to install 2 plastic tanks?!
Faster than I've worked..
Very nice project. Lowered, painted, 18's, T56, SuperRam'd 350... That's a recipe for happiness. 4.10 gears would make first gear useless on street tires but very fun! 3.42's would make it killer on gas though.."
Actually, I painted the cross member, under carriage, fender wells, painted the head light buckets, headlight frames, painted the manual pedals, painted the front fender well plastic covers, installed cowl weatherstrip, changed the speedo cluster to a 140 mph, re upholstered the vinyl on the tonneau cover and installed it, and installed new trunk shocks. I also went online and bought the complete Ls1 front brake conversion ( just waiting for the hubs), lca rear brackets, adjustable panhard bar, kyb struts/ shocks, new third light, door strikers, door grills, door handles and locks, manual antenna, new front lights, convertible latch release, coolant/ washer bottle caps, complete suspension polyurethane kit, new upper console, hood insulation, used trunk panels, all new exterior emblems, and hood bumpers. I also came across a 9 bolt posi rear end with 3.42 gears and disc brakes for cheap. Most of these things already came in but it takes time and patience. I'm having fun building it.
My hood inserts are being modified in order to bolt them on better,,,,, the spoiler is also being modified for the same. I ordered a set of 18x10 KWC RIMS with 6.5 bs.
I know I'm missing a few things,,,,,
"1 month to install 2 plastic tanks?!
Faster than I've worked..
Very nice project. Lowered, painted, 18's, T56, SuperRam'd 350... That's a recipe for happiness. 4.10 gears would make first gear useless on street tires but very fun! 3.42's would make it killer on gas though.."
Actually, I painted the cross member, under carriage, fender wells, painted the head light buckets, headlight frames, painted the manual pedals, painted the front fender well plastic covers, installed cowl weatherstrip, changed the speedo cluster to a 140 mph, re upholstered the vinyl on the tonneau cover and installed it, and installed new trunk shocks. I also went online and bought the complete Ls1 front brake conversion ( just waiting for the hubs), lca rear brackets, adjustable panhard bar, kyb struts/ shocks, new third light, door strikers, door grills, door handles and locks, manual antenna, new front lights, convertible latch release, coolant/ washer bottle caps, complete suspension polyurethane kit, new upper console, hood insulation, used trunk panels, all new exterior emblems, and hood bumpers. I also came across a 9 bolt posi rear end with 3.42 gears and disc brakes for cheap. Most of these things already came in but it takes time and patience. I'm having fun building it.
My hood inserts are being modified in order to bolt them on better,,,,, the spoiler is also being modified for the same. I ordered a set of 18x10 KWC RIMS with 6.5 bs.
I know I'm missing a few things,,,,,
Last edited by M3638; Dec 28, 2013 at 07:17 PM. Reason: Errors
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
Tonneau cover w/new vinyl,, don't really like the way it came out but it looks ok. The fiberglass was cracked/ broken under the vinyl so the guy put some thin sponge material under to fix it. Good for now.
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From: Alamogordo, NM
Car: 88 Formula 350
Engine: 5.7
Transmission: T-56
Axle/Gears: 9" 3.89
Re: 1990 Iroc Convertible Build
Looks good! I like that you are going with a superram! I have been looking for an Iroc 'vert for a while now! Looking forward to seeing updates!
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
"Looks good! I like that you are going with a superram! I have been looking for an Iroc 'vert for a while now! Looking forward to seeing updates"
Thank you.
Thank you.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
I'm looking for some help with the relays that are located on the driver side firewall. When I got the car it was a mess and I'm trying to get things in the right places. Can anyone help with a picture of this so that I can place them right?
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
Let me expand a little, I know how the bracket goes but when I took them off there was one relay hanging, one attached to the inside of the bracket and one outside,,,,.
Thread Starter
Joined: May 2013
Posts: 340
Likes: 4
From: Alta Loma, Ca
Car: 1990 Iroc Convertible
Engine: LS1
Transmission: T56
Re: 1990 Iroc Convertible Build
For future reference, my spoiler was modified by a shop in order to have no further problems with the studs. They attached small metal plates with rivets, rivets were covered with bondo on the top side then welded studs in place. Not a clean job but it was done for free.
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From: ocklawaha FL.
Car: 81z-28,89gta,91z-28 03 1500
Engine: 355,L98vette tpi,327
Transmission: TH350/700R4/700r4/4l80E
Axle/Gears: 3;73/3;27/2;73/3;73
Re: 1990 Iroc Convertible Build
Wow! Nice lookin vert..I just picked up a 91 vert project that I'm going to finish when I get my 85 Iroc done...going with a similar color on my vert...mine is going to be indigo blue..I love the wheels!! Think I may get the similar to yours..the 6.5 back spacing tuck under the car with no mods?




