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Road race Caprice build

6489 Views 51 Replies 12 Participants Last post by  toonwarrior
I'm posting this build here because of all the performance mods I've already done. It's an oddball but it's a genuine b-body. It started its life as a 1980 landau Caprice. It's currently a lowrider/sleeper/soon to be a fun as hell road racer. It's currently running a built Lt1/t56 combo w/fbody clutch pedals. I have 9c1 12" rotors up front. Tubular front control arms, 8.5 w/3.73's. Boxed rear trailing arms. ws6 front bar. 9c1 rear bar. Impala SS rear springs. Crown vic p91 front springs. Impala SS gas tank. Astro hydraboost. 9c1 steering box. Cherokee steering shaft. Chopped up 97 z28 cluster. Gbody buckets. 02 Taurus center console. The engine is a 383. Has CNC ported stock heads. Lt4 hot cam. 1.7 rockers
Mid headers. 2.5 dual exhaust. Torqhead 24x. Ford 80lb injectors. Fbody maf. Pcmforless tune.
255/40zr17 federal rs-rr on 17x10 wheels.
Ls1 Camaro rear disc brake swap.
Mods still in the works to be documented here are to add 05 Astro front spindles. 05 trailblazer hubs. 06 Gto front rotors. Ls1 fbody front calipers. Mark VIII independent rear suspension swap.
Add the ls1 fbody rear brakes and rotors.
I was gonna add a watts link or panhard bar, but I came this far so I'm gonna complete my dream of a lowrider/road racer. I'll post newer pics documenting all the mods soon. I'll have all my old suspension for sale also.
Land vehicle Vehicle Car Coupé Sedan

Vehicle Engine Auto part Fuel line Car
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I wanted the engine bay to have a stock look. I had to go old school Chevy orange. I'll post some of the finished engine tomorrow.

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My signature needs an update. My wife calls her Christine cuz she keeps coming back.
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Thanks fellas. I got a few pics I took today.

These are the wheels I'll eventually be rolling.

Some good ole' fashion engine porn!

I always thought the Lt1 and l98 were the purdiest engines.
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Just got done working on Christine. She's still a work in progress. Tonight was the 1st drive with the new tune. I also installed walboro 255 fuel pump and 80lb injectors per tuners instructions. It's running pretty strong! Haven't put a timer on it but the 0-60 feels faster than my z3. Maybe 5 seconds or less? If I get heavy on the throttle it smokes the heck outta the tires. By far the fastest and funnest car I've owned! Very pleased. It has a bit of surge coming back down to idle. Sounds like it wants to stall. I had to pump the gas to keep it alive or down shift while braking. It might be the iac valve. Gonna pull, clean the iac & check for vacuum leaks. Tried to hit Wally Mart tonight for some starter fluid to check for vac leak, but they close at 8:30 pm?!!? Damn dos xx virus!!! Either way it's pretty tough. I've driven faster cars but this big Bertha puts a cheeser on my face quick! And the glass packs are f'n loud! Money well spent! The fun part is about to begin! Can't wait to pass those z06 grandpa's at the track in grandmas old Caprice! I'm living for that! Make my pops proud. Sleepers rule!
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Haha! That's funny!
Hey I'd be happy to take a look at your tune file. Torqheads base tune is garbage. There's a lot of things that wouldn't even let my "stock" LT1 run. I have multiple setups and have had to fix everything myself.
I had the pcm programmed for my mods at pcm for less. Seems to run ok. What were the problems you corrected?

Why would that assortment of parts make a good combination? The trailblazer bolt pattern is unique to that platform. Are you planning to run TBSS rims or something?
My bad. S-10 hubs. 5x4.75.
The gto hubs are for the deep hat. I'd like to run my lowrider wheels now and then so deep hat rotor will be necessary.
Okay, now I understand the knuckles, hubs and rotors. Why the f-body calipers? Do they use the same bolt spacing as the Astro/Silverado?
The ls1 fbody calipers are basically c5 calipers. I have a set already. The bolt pattern on the knuckle is pretty wide so that will allow the brackets to be set further back for the deep hat. This is all theory. I'm hot rodding. Just reading and talking. Trying to figure out what will work for me.
It's cool when it works but frustrating when it don't. But you just get back to the drawing board.
It's not supposed to 'seem to run ok' after a tune.
It's supposed to be like, 'why was GM holding back on me? This is more like it!'.
You probably got Keith'd.
Might be the case. I say it runs ok cuz I knew there are a couple things wrong. I did the harness myself. My fans run constant and I believe I made the O2 sensor wires too long and the heating element is not working. That isn't the tune. That's my error. When I get these things worked out I will be taking it to get Dyno tuned. The pcmforless tune was to start it up.
This is rad. Always thought it'd be sick to build a boxy road course car. I've got a pretty set-up road course 95 9c1 LT1/T56 that I've been having a lot of fun with the last 10 years or so.

Where you located? Going to the Impala Nats this year? What tires did you go with? Don't quite recognize them.

If you need any track setup recommendations or anything like that, feel free to hit me up any time.

Couple of pics and a video from a trip to NYST about two weeks ago:
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That's pretty cool man! I love the smell of the track. Gasoline and rubber.
I'm in Arizona. Some buddy's of mine got me started when we went to sema in Vegas. We went to exotics racing and I drove a c7 stingray on the track. Was a blast. I bought a bmw z3 for $700. Rebuilt and stroked it and took it to the track. They have wild horse pass in Phoenix. They have a few tracks there. And a cool one in Deming, new Mexico. It's small but you can rent it for your own private use.
I will be running cheapy federal rs-rr. Not the best tires but they get sticky. I'm on a budget. I got 4 cars I'm I'm taking turns working on so budget is the key word.
I'd like to pick your brain when I got more time.
Worth noting:

The base C5 calipers are smaller than the Astro calipers. The C5 calipers use dual 1.6 inch pistons, and the Astro/truck calipers use dual 2 inch pistons. Use the factory 2003-2005 Astro calipers that are meant for your knuckle.
Cool to know. I'm a junkyard dog. I grab whatever I find usefully there for cheap. Rebuild kits aren't expensive either.
I appreciate all your help, advice, & knowledge. Most of the things I've done have come from guys posts on this forum. The t56 swap manual was of great help. The Astro rotor thread also helped. Lots of good info. I wish there was a thread on this 8.8 IRS swap into a b-body or 64-77 a-body out there. Would be great help.
An independent rear suspension would be tre cool, but not strictly necessary. Same goes for rack & pinion steering.
Plenty of cleverly reinforced and modified Caprices handle more than well enough to grow eyeballs, drop jaws, and embarrass 'exotic' sports cars costing several hundred thousand dollars.
Very true. I'm just dumb when it comes to this stuff. I got this idea and I'm gonna do it. I'm not sure what I'm getting into but this whole project has been new territory for me. I thought about a panhard bar or Watts link. The adjustability of the rear suspension is what I'm after. Camber, and toe. As well as the balance of the car it will all bring. It isn't the easy route for sure.
This is rad. Always thought it'd be sick to build a boxy road course car. I've got a pretty set-up road course 95 9c1 LT1/T56 that I've been having a lot of fun with the last 10 years or so.

Where you located? Going to the Impala Nats this year? What tires did you go with? Don't quite recognize them.

If you need any track setup recommendations or anything like that, feel free to hit me up any time.

Couple of pics and a video from a trip to NYST about two weeks ago:
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I was geeking out on your videos. That big girl moves! Stays nice and flat through the turns. That's a cool track. It's too hot out west for the track. I'll wait for fall. Chuckwalla in Blythe, CA is the nicest track I've been on so far. What's your suspension set up? Brakes? Tires? It looks like you have it pretty dialed in. Gear ratio? Still 350 or stroked? You have a roll bar?
Sounds pretty messed up for a shop to leave stuff like that. I've entertained to idea of self tuning but thought I'd leave that part to pros. So what does the total cost of all things necessary run? I don't even own a laptop.
I'd love to get to Chuckwalla, Thunderhill, and Laguna Seca is still very much a bucket list track. West Coast Trackation 2023? Haha. I got into modding this car after living near and driving all the awesome roads around Malibu CA some years back. Mulholland Hwy, Decker, Latigo, too good!

Before I jump into my car mods, I'd say the IRS is an ambitious project that I'd be keen to see done. As far as I know it either hasn't been done or hasn't been well documented at least. While it may not be super necessary for most tracks, it'd definitely be very nice on real world roads, same with rack and pinion steering. Even the best stick axle is still a stick axle. Mustangs finally gave it up after all these years, despite having developed a very very competent stick axle in the prior generation. FWIW, there's some fairly rudimentary techniques to bring some mild camber and toe to a stick axle, but certainly nothing I'd call adjustable, unless you would consider swapping to something like this bad boy:

but at that price, IRS swap makes just as much sense to me.....

I'll have to shoot you a PM on all the mods at some point, but it's honestly not that far from stock with A LOT of the basic chassis stuff.
-750in/lb front springs, cut Vogland rears
-Bilstein shocks AK1053 circle track front, reg Impala rear
-1 3/8"? big solid front sway bar, stock Impala rear bar after trying many others
-10 year old rubber bushings throughout, stock arms save for UMI boxed rear LCA's
-Dick Miller triangulation braces out back
-maxed neg camber(-2.0) front with lots of caster(+8), zero toe

-Astro Van front conversion with ducts, stock Impala/9c1 rear disc with ducts - "Got away" with stock front size for a few years until I skilled up and got faster
-G-Loc R16 front pads, G-Loc R8 rear pads
-Stainless braided flex lines
-Motul RBF660 brake fluid

-Stock Impala 17x8.5 wheels, cheap and strong, but heavy
-255/40/17 Falken 615k+ tires - "Square" setup is nicely balanced, easy to rotate around car and cheap! These tires last a loooong time too.

3.73 final drive from my auto trans days - tall, but effective with all the available torque and stock engine redline - nice 75mph hwy [email protected],800rpm

Engine is bone stock OE 198k mile iron head LT1, with intake, full exhaust and mild 93oct tune.

One of my bmx buddies is a drag car fabricator, and built me this nice 4 point roll bar to my specs, so the back seat area is not intruded upon and I can still put all my track junk back there, since I still drive the car to every event. The cargo space is nice!
Here's a link to my rollbar thread:

That's a pretty conservative setup. After running that setup, what would be your next upgrade? It looks like crazy fun to drive. I can't wait to get my girl out there!

My buddy has a 97 t-bird that he tracks. It's pretty big too. We rebuilt the engine and added bigger heads cams intake, a fuel cell, coilovers, big brakes, radiator. That thing had crazy body roll. The fenders were cutting into the tires! We adjusted the coilovers and took her back out. We blew the trans and called it a day. Got it on the lift to see what the problem was. We forgot to bolt the front sway bar to the lower control arm! Haha! We ain't pros that's for sure!

Anyways, that's where I got the idea for the rear IRS swap.
That axle looks pretty awesome. I heard about the back yard way to heat the axle in the right spots to get camber and toe. Wears the ball joints though. I'd go with a heidts, roadstershop, or art Morrison irs for about the same price. This swap is pretty low buck.

Did you go with the f2b conversion or did you diy it?
I'll have to check the roll cage thread. I'd like to go that route but I enjoy the luxury of the 80's interior. I'd like to keep it sleeper/cruiser. I have an 84 Corvette that I'd like to put a cage in. I'm building a carbed 350 for it. I have a zf 6speed for it. That one is gonna be all track.
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I bought the IRS on the 11th and it's been stuck sitting in a shipping warehouse for the past 2 weeks. Damn Corona! I been itching to get going on this swap!
What IRS rear set up are you putting in the car ?
97 Mark VIII irs. It's a popular classic truck swap.
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