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-   -   Darin's FB ITGT FB build (https://www.rx7club.com/race-car-tech-103/darins-fb-itgt-fb-build-879959/)

nofords 12-29-09 01:03 PM

Darin's FB ITGT FB build
 
Well, I have had several requests for information and I've noticed that the questions are starting to be the same. In this case, I have decided to do a build thread.

As I had initially no intention of doing a build thread, I do not have drastically detailed images and step by step processes that many others do. I do hope that what I display here helps someone along the way!

Keep in mind here that due to the fact that I do not work in a well ventilated area (mainly because its -10F outside my shop), that I am only tacking many non-structural parts of the car until I can push the car outside and fully weld and dress the components. All structural components will be fully welded inside however!

The car is an '82 FB with a sunroof. The car will keep the sunroof as I am of such height that it will be my main entry and exit of the car. The front fenders will be vented behind the front tires to allow air to escape from the wheel wells as well as extract heat from the engine bay. There will be no other body mods except the SCCA front bumper and Imsa rear spoiler. According to the rules, I cannot attach any other product to the exterior of the car that did not come originally equipped or was available from the manufacturer as an option.

Moving from the front to the rear, the car has FC front subframe, large port S4 turbo II engine sporting a GT45, mustang turbo intercooler and megasquirt. I am using a S4 Turbo tranny with an A/T yoke GSL-SE D/S and GSL-SE rear.

Due to budget concerns, I will be running stock S4 Turbo wheels with 225-40-16 rubber. I know they are heavy, but I may actually need them to get my min weight of 2375lbs.

And now, on with the show...

nofords 12-29-09 01:35 PM

Finally, Pictures!
 
When i brought the car home. I stripped off the sheet metal "doors" that were on it as well as the bib that was accross the front.

Here is a list that wasn't rotted out:

The trans tunnel
The roof
The sunroof

I made the mistake of hopping into the car feet first and fell through the floor like Tim 'the toolman' Taylor. :lol: The lack of the floor was the first thing to go!

http://i56.photobucket.com/albums/g1...B/P8190011.jpg

http://i56.photobucket.com/albums/g1...B/P8190010.jpg

http://i56.photobucket.com/albums/g1...B/P8190008.jpg

http://i56.photobucket.com/albums/g1...B/P8190007.jpg

http://i56.photobucket.com/albums/g1...B/P8190006.jpg

http://i56.photobucket.com/albums/g1...B/P8190009.jpg

nofords 12-29-09 01:40 PM

The floor:
 
As i have a slight lack of build photos, here you can see my stitched floor with scrap tin I had lying around.

The floor braces were swiss cheese so I cut them out and placed in 1"x2"x0.120" box channel as a "subframe connector" and then using the same material, connected the a-pillar bars at the floor to the subframe connector.

http://i56.photobucket.com/albums/g1...B/PC290005.jpg

http://i56.photobucket.com/albums/g1...B/PC290008.jpg

http://i56.photobucket.com/albums/g1...B/PC290011.jpg

nofords 12-29-09 01:47 PM

The Passenger Door:
 
Because I didn't have any doors, I scored a couple off a GSL-SE that was lying around so if anyone needs power window regulators, wiring or glass let me know.

I gutted the doors of all the useful stuff and then cut the panels off with my plasma cutter. I cut the door brace out too with an angle grider.

The rules of the game say that I must use factory hinges and the door must open and close as the car came from the manufacturer so that is why I left the bracing at the front of the door. Once the car is moved outside once again, i will smooth and dress the edges with a hammer/dolly. All hinges and exterior handles function as normal. I have to figure out a way to open the door from the inside for the driver's door.

I haven't weighed the doors but I suspect they are 20lbs lighter. It's a one man job to take them off and put them on now!

http://i56.photobucket.com/albums/g1...B/PC290021.jpg

http://i56.photobucket.com/albums/g1...B/PC290022.jpg

nofords 12-29-09 01:56 PM

FC Subframe:
 
I don't have any progress photos of this either however:

I placed the subframe about 1.25" rear of the original FB subframe and reinforced the frame with bolt tubes that are fully welded top and bottom. I used the FC steering column and just made mounts to place the column at the desired location for my comfort. I will be using a removable steering wheel with a grant aluminum wheel.

I will be elaborating on the suspension later however, I was able to get the FC strut brace and adjustable pillow mounts to fit w/o modification!

here are a few photos of the engine bay with my mockup engine and gutted tranny...

Notice the monster intercooler! (31x14x4) it looked a lot smaller on the computer screen when i ordered it! Measure twice people!! Luckily, i did and it fits perfectly!

http://i56.photobucket.com/albums/g1...B/PC290020.jpg

http://i56.photobucket.com/albums/g1...B/PC290010.jpg

http://i56.photobucket.com/albums/g1...B/PC290009.jpg

http://i56.photobucket.com/albums/g1...B/PC290015.jpg

nofords 12-29-09 02:04 PM

S4 Turbo II Tranny Mount:
 
Here is the mount I made to bolt in the rear mount of the Turbo II trans:

I used some 1x1x0.100 angle and 1x1x0.100 box channel to use as my x-member

http://i56.photobucket.com/albums/g1...B/PC210012.jpg

Then cut an angle and curve cut the box channel

http://i56.photobucket.com/albums/g1...B/PC210015.jpg

All welded up:

http://i56.photobucket.com/albums/g1...B/PC210022.jpg

http://i56.photobucket.com/albums/g1...B/PC210021.jpg

I'm using a poly LCA bushing from a 98-2000 Malibu as my mount into a piece of pipe.

http://i56.photobucket.com/albums/g1...B/PC210017.jpg

http://i56.photobucket.com/albums/g1...B/PC210019.jpg

nofords 12-29-09 06:05 PM

Finishing the Tranny X-member:
 
finished the x-member. Still trying to work out the kinks. Right now, the engine and trans are kah-kah in the car. I have to figure out how to swing the engine over. It may be that is the way it has to be but i don't like it.

I think i may shim the trans up some more. I have 3/8" above the tranny to go up but am not sure if I will. I am going to test it and see.

Oh, my steel is not 0.100 wall as shown in the photos. I am using 3/16" wall angle and box channel.

Photos:

http://i56.photobucket.com/albums/g1...B/PC290024.jpg

http://i56.photobucket.com/albums/g1...B/PC290026.jpg

Perfect_Weapon 12-29-09 08:41 PM

I really appreciate your offerings here. I'm very interested to see how this goes as I've been paralyzed with what to do next with my FB. Keep 'em coming and good luck. I'll be watching with wide eyes.

Bruceman 12-30-09 07:28 AM

Nice job bringing an FB back to life!:)
It looks so similar to my winter car except not quite as much rust. Keep up the good work

Kentetsu 12-30-09 11:47 AM

Nice work man! Please keep us updated on the progress. :)

What are your plans for suspension?


.

nofords 12-30-09 09:50 PM

For the rear, I have converted it to 3 link and plan on using strange engineering coil over shocks mounted in stock locations to comply with the rules. I will be using 200lb 12" shocks with adjustable compression and rebound.

Here is one of my links. They are aluminum with QA1 rod ends.

http://i56.photobucket.com/albums/g1...B/PC290012.jpg

For the front, I am trying to figure out a short shock setup. I am trying to see if I can get a insert that fits into the stock strut housing or another strut that works. The problem is that with the tire set where i want it, i only have 2" of stroke left on the stock FC strut. I may have to run higher than I wanted. If I have to run stock fc suspension, I will run KYB AGX fronts with coil overs.

nofords 12-30-09 09:52 PM

Passenger Rear Quarter:
 
Fixed the passenger rear quarter today.

In case someone didn't know, a driver (left) front fender fixes the rear passenger's (right) side and the front passenger (right) fender fixes the rear driver's (left) side. All body lines match. Just have it tacked for now. Need to finish weld and grind flush. Gives about 8" matching rocker panel behind and under the door! Oh, and due to the curvature of the fender, you get about 1" of automatic fender flare that looks 100% stock!:naughty:

http://i56.photobucket.com/albums/g1...B/PC290002.jpg

http://i56.photobucket.com/albums/g1...B/PC290003.jpg

Kentetsu 12-31-09 11:29 AM


Originally Posted by nofords (Post 9708036)
For the rear, I have converted it to 3 link and plan on using strange engineering coil over shocks mounted in stock locations to comply with the rules. I will be using 200lb 12" shocks with adjustable compression and rebound.

Here is one of my links. They are aluminum with QA1 rod ends.

http://i56.photobucket.com/albums/g1...B/PC290012.jpg

For the front, I am trying to figure out a short shock setup. I am trying to see if I can get a insert that fits into the stock strut housing or another strut that works. The problem is that with the tire set where i want it, i only have 2" of stroke left on the stock FC strut. I may have to run higher than I wanted. If I have to run stock fc suspension, I will run KYB AGX fronts with coil overs.

As far as the rear coilovers, this has been discussed many times over the years. The general concensus is that it can be done, but a lot of reinforcing must be done to the shock mounts. In the stock setup, the weight of the car is not carried by the shock mounts, so they aren't designed to carry that kind of load.

As a possible alternative, have you considered the adjustable rear perches from Respeed? That is what I went with, and they work great. http://mrcmfg.com/catalog/product_in...roducts_id=367

Billy from Respeed might also have some advice/ideas on your front suspension. You can reach him here on the forum by PM (Bwaits_).

Good luck. :)

nofords 12-31-09 11:53 AM


Originally Posted by Kentetsu (Post 9708910)
As far as the rear coilovers, this has been discussed many times over the years. The general concensus is that it can be done, but a lot of reinforcing must be done to the shock mounts. In the stock setup, the weight of the car is not carried by the strut mounts, so they aren't designed to carry that kind of load.

Have you considered the adjustable rear perches from Respeed? That is what I went with, and they work great. www.re-speed.com

Billy from Respeed might also have some advice/ideas on your front suspension. You can reach him here on the forum by PM (Bwaits_).

Good luck. :)

I read those threads on this forum and the problem i have with that comment is that the shock points take just as much vertical loading (or more) as the springs do. The shock tower has to withstand "shock" forces in both compression and tension and resist those changes instantaneous to each other. The shock has to counteract the force of the vehicle coming down (or going up) on the springs to the point of stopping the vehicle in vertical motion.

Now, in saying that, my shock towers are tied into my roll cage vertically and horizontally, and have been reinforced by other means such as stress welding and heavier steel.

The issue I have is with the adjustable spring perches is that in order for me to run coil springs at the track, I need to have limiter straps to stop the springs from flying out at full extension. These unfortunately cause wrapping and binding in rare cases and can have nasty consequences. My fellow team mate had an unfortunate incident with the straps last season and caused him to go off into the field plowing it with his new front bumper. :icon_no2:

This is why I chose, coil-overs! :nod:

Kentetsu 12-31-09 05:56 PM

Rather than using straps, I use short Bilsteins. :)

nofords 12-31-09 06:27 PM

straps are part of the rules! If you have coil spring and shock absorber, they are mandatory in my class. :(

Kentetsu 01-02-10 11:34 PM

Wow, even if the spring is still under tension at full droop? That would suck...

nofords 01-03-10 01:26 PM


Originally Posted by Kentetsu (Post 9713157)
Wow, even if the spring is still under tension at full droop? That would suck...

Yup! Don't matter if they are short or not. Must have "Internal Spring Tethers" if the suspension has coil spring perches separate from the shock absorber.

Got my rear in today. Pics to come.

nofords 01-06-10 09:38 PM

Wheel Tubs, GSL-SE Rear Install and 5 Bolt Conversion
 
Finished up my wheel tubs before i put the rear axle in. The passenger side i did first trying to mimic the original with curved top. Didn't work out so well. Looks real bad in the photos. I ended up getting frustrated with the dolly and hammer so I just flat patched it. The other side, I just made your typical hot rod squared off wheel tub.

http://i56.photobucket.com/albums/g1...B/P1060004.jpg

http://i56.photobucket.com/albums/g1...B/P1060003.jpg

I got the rear installed with the factory shocks and my new aluminum LCA's. Once my Strange Engineering double adjustable coil overs come in, i will install them along with my pan-hard bar. At this point, I have to order my third link now that I have the rear placed where I want. Hopefully that will arrive soon.

As the front has GXL/TII subframe (5-Bolt) i am converting the rear to 5 bolt as well. Drilled and slotted FC rotors, calipers and pads in all four corners.

Before

http://i56.photobucket.com/albums/g1...B/P1060001.jpg

After

http://i56.photobucket.com/albums/g1...B/P1060005.jpg

nofords 01-06-10 09:47 PM

Fuel Cell
 
Also got my fuel cell in. It's an aluminum drag tank with a sump. I won't be running this tank as it's intended (obviously by putting it into a road race car), meaning that I'm not running the sump. It will be capped and I will install a stock FC pickup and flange into the passenger side of the tank. The pickup will be running dual walbro's.

My camera batteries died so I will add to the mounting and some exterior shots later but this is the mount so far:

The tank has mounting tabs on the the bottom which are bolted to 1x1 box channel running from each frame horn front and rear. There are two straps stopping the tank from flying up into the cab as shown in the photos. I need to setup some kind of bulkhead so if anyone has any ideas, please pass them along!

http://i56.photobucket.com/albums/g1...B/PC290007.jpg

http://i56.photobucket.com/albums/g1...B/PC290013.jpg

http://i56.photobucket.com/albums/g1...B/P1060002.jpg

TrentO 01-08-10 02:42 PM

I started building my TII for ITGT. I read your specs and in my opinion the first thing you will want to do is get more rubber under the car. I'd also suggest a brake upgrade. I ran a CC car for five years and then built my ITGT car. My website is in the process of getting torn apart and put back together, but I'll try and make some progress. www.rxracing.com.

nofords 01-08-10 05:18 PM

the issue with the rubber is that I'm maxed out at 7" wide wheels as per the rules. This maxes me out at 225 which is the widest tire that i can "safely" run. IF the car was full GT class, it's eligible for GT3 ie: 7" rim. If i get the car to GT2, I can run 10" but that means I have to be heavier and make a ton more power to get my PTW ratio as close to 6.5 as possible.

As it is, I will have trouble meeting my min weight of 2375...that is of course, I didn't mess up my calcs based what they had in the book.

TrentO 01-15-10 04:01 PM

225's Toyo RA-1's are maybe good for 300 rwhp. You go beyond that and it is almost impossible to use throttle in a corner. I ran with around 340 rwhp and I had to soft pedal every corner until the car was pointed dead straight. Soft pedaling a turbo car really sucks as when you start to pick up the throttle, the turbo starts to spool and you have to back out.
With the 280 yokohama slicks, I can ride full boost (400 rwhp) through the apex without an issue.

-Trent

nofords 01-17-10 08:17 PM

Small Update
 

Originally Posted by TrentO (Post 9739492)
225's Toyo RA-1's are maybe good for 300 rwhp. You go beyond that and it is almost impossible to use throttle in a corner. I ran with around 340 rwhp and I had to soft pedal every corner until the car was pointed dead straight. Soft pedaling a turbo car really sucks as when you start to pick up the throttle, the turbo starts to spool and you have to back out.
With the 280 yokohama slicks, I can ride full boost (400 rwhp) through the apex without an issue.

-Trent

I am going to start small on the boost and tune the car's suspension and steering so I am planning on running azenis RT-615's for now and then go to either Toyo RA-1's or GY R1's. I have to stay away from slicks as they aren't allowed in my class.

Not too much progress as I was very ill for the last two weeks.

I finally finished my 5bolt conversion on the rear. I got my intercooler lower mount finished and installed my rad.

The rad I am using is a toyota tercel rad. It's 3/32 shorter than the width of the frame rails and extends full height from the underside of the frame rail to 3" below the hood when closed. I have a worn out rotten plastic one in the photos for mock-up but will be using the aluminum racing version for driving.

Also got my engine mocked up however, I have come to the sad realization that my FC NA strut tower brace won't work as the water neck, alternator and PS pump are in the way...or the brace is in the way of the accessories. I will have to construct my own I suppose!

Only one useful photo today...

http://i56.photobucket.com/albums/g1...B/P1170010.jpg

Hyper4mance2k 01-31-10 12:37 AM

where did you get the heim jointed lower control arms?


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