427seven

Should have a teaser video on utube this week... off the rev limiter @7000rpm 2nd gear rubber.....

427seven

And just to head off the inevitable question, no it doesn't rub, rattle or thump anywhere through the rpm band, over bumps or anywhere. It is perfect.

t/aws61985

iTrader: (2)

What Kind of brembos are those?

427seven

Monoblocks with integral bridge, fronts are GT6 and rears are GT4's, rotors are all 14" spec37 , sized to allow the steel rotors on the street and carbon ceramic on the track.

TTOP350

iTrader: (8)

Have any pictures of the front caliper mounting parts and the hub used?

427seven

There were no kits available for mounting a huge brake system to the third gen, so I designed and fabbed a prototype, then had them milled from billet aluminum. There were two different spindles available, a light duty version and a heavy duty version (used for production of the 1LE spindle), these of course are the latter. The hubs are BAER aluminum.

427seven

The spindles that are actually on the car are not GM of either variety, they are the BELL drop spindles, but the mounting parts fit the same. This design can easily be altered to accommodate 15" or 16" rotors as well.

TTOP350

iTrader: (8)

Very nice work! Looks similar to the setup I started doing for the older 4piston Brembos and 13" rotors

Aviator857

Fwiw bigbrakeupgrade.com makes brackets to use ctsv and gen 6 Camaro brakes, but yours are a very nice solution... This may be the first a 6 figure build of a thirdgen that I have seen.

Aviator857

What bell spindles are you using I didn't think anyone made street use drop spindles for these cars.

TEDSgrad

iTrader: (4)

Very similar approach to what I did, only I stayed small for un-sprung weight, AND fit them behind the stock wheels: RaceCraft RR 2" drop spindles, alum hubs, FSL Narrow Wilwood 6pot with bridge bolt, 2 pc curved vane rotors (12.81). My stopping power is rubber limited, not brake size limited.

An 18" wheel would allow for a flat BJ style tie rod end to fit inside the barrel of the wheel, but I don't want the weight cost, poorer scrub radius, and not much sidewall for the straights at Road America.

J.C. Denton

iTrader: (1)

That is absolutely insane! Now that's real car ****! No way to drive such a built car here in germany, forbidden in every single way!

straightbuchana

I'm loving all these pics!! You really did an amazing job, I don't think there's any one who can say they're the least bit unimpressed with any part of the build - I know I'm not. Can't wait for the video!!

427seven

The transmission is a built TH400 with a 3000rpm stall and modified valve body that holds in gear until it's shifted. It is not a full manual valve body. It has a Gear Vendors Overdrive behind it, and is managed by an electronic bump shifter that sequences the gears. The resulting split makes for six forward gears that can only be accessed by using the bump feature, if you want to go from 3rd to 5th you bump twice, etc. There is potential in this system for paddles, and the plan is to add them this winter. It has a massive cooler in the back of the car and it's system holds 10 litres. No issues cooling even idling around in traffic on the hottest days. The engine has been startlingly good this way too, it idles quite well at 1200, and doesn't overheat under stress. The only problem so far has been the inability of the operator to shift quickly enough, this engine revs right now.

427seven

I had to laugh for awhile about the drill instructor, I had one of those too, HE was a MF..... Good memories though....

427seven

That would be plenty of brake for these cars, remember the system that the Firehawks used to compete admirably in Showroom stock....? You should have them on!!

427seven

I measured up both systems the CTS and Camaro as well as some Vette, Wilwood and BAER, but all of them had either a removable bridge or were not a monoblock design at the time, so went for the Brembos. They are expensive, but they are a no nonsence caliper that is all about max performance. A bit of bling, too.

427seven

Back in the 80's, you could get 2" drop spindles from Bell Tech. They still make drops, but only for trucks these days. They were superior, I used them on my race car and always had a spare set of everything I could, so when I stopped racing I still had a set. I love them, if you do nothing else to the car, these change the look completely without adversely affecting the design characteristics and geometry of the front suspension. That includes things like track width and the ever important bump steer. Maybe with some begging and a resurgence in third gen interest, they could be persuaded to begin producing them again. We should start a letter writing campaign and bug the hell out of them. hahaha...

427seven

I love seeing pics like this, they remind me...… well you know. What classes are you allowed to run with those kind of mods? Because I ran Production classes in ICSSC and SCCA, we were very limited in what we could do to the car, especially in SCCA. The jacks would have been awesome to have, back then I almost built a set for myself after seeing them in a Regional NASCAR stocker. I found out we weren't allowed to use them, but two of the tracks I raced could not have been more different, Seattle was long and rough, Portland was glass smooth, so the car could be dropped really low there but not at Seattle. I'd have to change the whole front suspension going from one track to the next, lots of times just days apart.

427seven

Seriously? Lotsa places over here we're not allowed to either, we just do it anyway. What about the ring?

TEDSgrad

iTrader: (4)

I'm in a class all by myself, LOL. Just HPDE for fun - fun is the key.
My build philosophy was for me to build (limited skills) the most agile car I could from a 65 mph roll. Drive it in all lower 48 states and on RA for fun - I am an original owner. Have MS & LA left, plus everything North of Yankee Stadium. Wow, I've owned it for 30 years this summer! If only I could hold up to be improved upon across those 30 years, ha.

TTOP350

iTrader: (8)

I got lucky and now I do!!! (not sure why these are upside down) I'd still like a set of black 6 piston calipers and 14' rotors for my other car though


What I started to do.

Until I got super lucky and found these. They're from a Firehawk supercar series racecar. Only 1 season on them, moved to different class and pulled these off.

battmann

iTrader: (9)

427seven

Pics are upside down bc you must have taken them with a phone... they will orient in whichever way yer phone happened to be when you snapped em. I've been shoveling snow so it was a good thing having them upside down, I straightened out my neck turning the other way to look at them....

427seven

Dunno if jealous is the right word, maybe appreciative??? When someone can complete a build, there are many things that get learned, and can be passed on. Information is better than money my friend, it can be shared without any loss to the giver.... Anything learned can be shared and everyone benefits. If you have a car that you love just keep working. It was 13 years before I took a "maiden voyage"....

dabomb6608

iTrader: (3)

Hats off to you on this amazing build. It's truly one of a kind.

427seven

link to a video.....

Linson

This is a most impressive build. I like everything about the car, but am not sure if I'm on board with the title of the thread, "A Firebird GTA the way they should have built it".
I mean, come on. Are we really gonna hold circa 1989 GM to this standard? Should they have put a modern day, aluminum 427 in an F-Body, 30 years ago? Sure, why not.

427seven

Like I said earlier, I've owned them since they were made available, the shape is extra ordinary. To have watered down the offering the way they did had to be remedied. My first one was a loaded T/A with an LG4. Really?? Needless to say it was immediately replaced by a potent 355 on nitrous that went into the 11's with street tires.... Like I said earlier in the thread, "There were three MAIN objectives, Build it the way they should have, (using parts that were at least similar to ones available during the 80's) use as many stock and off the shelf parts as possible (to make it reproducible), and keep it looking as stock as possible (both interior and exterior - no big fender flares and $100K interiors. As the rear end was available and even tested by Pontiac in the 80's, it was a motivating factor. The reason I used an original small block design was because that was what was available then. GM was selling aluminum versions for racing, and they not only are capable of sick horsepower, the weight distribution and overall weight loss made it a no brainer. " I had to do it, sure it benefitted from some of today's technology, but I was road racing in the 80's, and there was some very exotic stuff out there then.

Lovin My Bird

Lovin My Bird

427seven

Got tired of following?

DynoDave43

iTrader: (11)

Me too!

Welcome aboard.

Anti-Venom

Can't believe I missed this one. Absolutely amazing build! Definitely one to be proud of.

427seven

Lotsa people asking about the lights. I will be starting a "how to" soon as this is currently experimental. The light boxes are fabbed, and printed boxes are in the werks. The lights are LED, stacked phaser tubes for the DRL, and DOT 5 pot LED's for the heads. The signals and parks have been moved to a fabbed box next to the LED spots in the fog hole.

427seven

DTR's

427seven

parks...


headlights

Fogs

427seven

phaser tube is thin, two stacked is a perfect fit.

QwkTrip

iTrader: (22)

Is that tire a Hoosier Circuit DOT Radial?

straightbuchana

Nice video, it sounds great! I can die happy, now

427seven

Hoosier, R3S03, they don't sell them anymore, but if you know people..... BC of my racing associations I have access to a very limited supply.

427seven

Oh, don't DIE! Unless you're sure you're going to heaven, I HAVE heard that the Firebirds and the Women there are all 10's... Since I only have first hand experience down here though, I'm gonna stay for a bit yet - I hope...

427seven

Over the past few days I have been navigating a few of the other threads on the site, getting to now the place. Thanks LINSON, from you this is a compliment, especially since you're a fellow NorthWester...

Street Lethal

iTrader: (16)

Just when you thought the FasterProms C4 was the best sounding small block on planet earth, along comes this GTA and immediately steals its' thunder. This thing sounds absolutely incredible 427seven, well done!

- Rob

427seven

you watching the linked video or on utube. I don't know why but the picture quality and the sound are so much better on utube, I think they have to shrink the quality to channel it through our site. I will be putting on some drag race clips, those scream...

427seven

And thanks for watching!!

QwkTrip

iTrader: (22)

I notice you have the stock brake combination valve. Any tricks in there or stock as a rock? Did you grab one from a certain year/model?

I have a Wilwood 5-port proportioning valve with M10 fittings and it has been nothing but a nuisance. Fought leaks forever. The first one had a cracked housing and I exchanged it. Tried different brands of tube nuts, homemade flares with high end tools, manufactured flares, and the list goes on. It finally stopped leaking but the fittings are now so tight that I'm concerned something is going to split and I'll lose my brakes. Car is torn apart at the moment and I'm thinking real hard about going back to stock valve and hard lines, maybe even the stock master cylinder too. I even have all the parts sitting here -- that's how close I am to pulling the trigger.

427seven

I am using a stock system, but you need to calculate a few things before deciding what to use. I can't tell you how many times I've heard stories like yours, unfortunately people have a tendency to tell you what to use based on what they are using rather than what would be best for you. There are so many variables that you can't just say one thing will work. Two identical cars will have different drivers, and what they want makes a difference. In order to make a good decision, you first need to make a list of what you WANT. Is it primarily for the street, or the track. Do you want instant response, or do you want to really be able to modulate or work your pedal. These cars (third gens) don't have ABS so you can factor other ways of using the brakes. How heavy is your car gonna be, what diameter are the rotors, what material, are you using the stock pedal assembly, what are those dimensions.... on and on. As a GENERAL RULE of THUMB, personally, I always start with the stock systems. There are enough variations that you can almost always find one that will put you in the "workable" range. When I first started racing, after fitting the 1LE brakes to my car, I experimented for a long time with a variety of Master Cylinder/proportioning combinations and ended up with one from a 4 cylinder firebird that had weeny drums in the rear. It worked perfectly. When I put the Brembos on my car, I thought I might have to spend a ton on an aftermarket braking system, but after trying to consider everything, I focused on two stock systems, one a factory f car drum system, and the factory J65 system that I ended up using. If I were gonna race it, I would use a system with a smaller diameter piston in the master cylinder because of the quicker punch you get with it, but on the street the factory one works awesome because it's not too grabby but binds hard when you pound the pedal. The pad choice is important here too. There are many self help and how to directives on line, and go into much more detail than I can here. Maybe I'll start a brake thread one of these days.... when I have time....

QwkTrip

iTrader: (22)

Thanks. I have a hot street car and I want to be able to modulate the brakes. I might do some kind of racing once a year for fun. Nothing competitive. You know, just see how the car stacks up to the competition now and then.

I'd sure appreciate the write up on sizing brake system components. I gave it a solid effort to do that myself when I was troubleshooting the problem. Probably 85% of what I did is good. The rest is probably junk. I think I got to the point where I have all the necessary physical data on a variety of master cylinders and brakes, except I don't have the pad coefficient of friction (so I made assumptions). I've got the math to predict front & rear brake torque, pedal effort & travel (including manifold vacuum assist). I've got some graphs that do 'what if' scenarios across a wide range of weight distribution, and it allows you to fiddle with tire sizes and friction coefficients. But I've never modeled the effects of prop valve on rear line pressure, and all my efforts are useless without that.

427seven

Yes, your car IS a hot one. I checked it out, and commented on it over on the January COTM thread. Anytime you increase the effectiveness of your brakes, especially in the rear, you have to get it all figured out. I know guys who slap 6 piston calipers and big rotors on these things because it looks cool, and find out they cant push the brake pedal bc they just lock up the rears all the time. This is especially true for a car with a front weight bias. So then they put a big adjustable PV in the rear line and effectively shut down their rear brake just so they can say they have a 6 piston binder in the rear. If you can shed some front end weight or shift it around, then you 'll be able to use a bit more brake in the back, but those needs won't ever equal the needs yo have in the front. Sounds like you have it pretty much done, just final figures and decision time.
I have stacks of material on figuring out brakes, I have a really good magazine article - somewhere - that breaks down the physics nicely. I scanned all this stuff to pdf's so it's lost in the pile and I'll have to look for the right one and I'll try and get it to you. Unfortunately, when it comes to things like specs for certain brands, you have to do a bunch of footwork to get them, manufacturers have a tendency to ask you what kind of a car you have and give you something they think works without sharing too much information. So after you figure all this stuff out, you're kinda back to experimenting. If I were you , and I was at THAT point, I'd put it back to stock and then just adjust the points that prove deficient.
Yes I really like your car.... In fact I looked for and was so close to buying a red 88 Formula when I found mine, bought this one cause it was right time right place right price and really, ended up being the right car....