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Discussion Starter #1
Hi All, I just picked up this OCC. Has TBI L05 350 and 700R4.

I took one test drive and had to have her, I fell in love with my bubble butt wagon. I saved her from a field in Kunkletown, PA. I paid 1800 for her which is way too much but is water under the bridge. The interior is very nice and the rust isn't too bad. I want to swap her to an LSx platform and T56 eventually, but first, have to make her roadworthy.
All the brake lines need replaced, so that was my first order of business. I drove her to my buddy's house and put in all new brake line. Also eliminated the Audacious Bull **** system while I was at it. Here are some pics:

This is the mess I pulled out........

New Left side line

T fitting to replace ABS crap and part of new passenger side line

New rear line ran and front line hooked up to prop valve (complete with factory-looking curly-cue bends to allow movement due to frame flex)

Lines hooked up to prop valve

Master cyl cleaned up and installed

My homebuilt (and short lived) brake bleeder :)
4 used tires later, new rear wheel cylinders, new front pads, and rear shoes later, and I was ready to take the beast for safety inspection. She passed. I still have to fix the rusted out spare tire well, lucky that inspection tech didn't notice the undercoated duct tape :-D

A week later I bought a 1992 caprice wagon that had a 3.23 posi rear in it, was going to use it for parts, but decided that she was too nice, so I got my best friend to buy it off me. I paid 800 for it, and sold it to him for 400 since I took parts off it. Here it is after I got the rear out of it. We put my old open rear in it and Murray is going to use it as a scrap hauler. He got bitten by the b bug too. I sold it to him so cheap because I just could no longer see him suffer with a 307 olds motor that he is currently driving, the LO5 is a powerhouse compared to it, lol!
Side view of my wagon

The Caprice!

My old open rear before it went into the caprice

More Caprice goodness
 

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Discussion Starter #2 (Edited)
More OCC stuff!

I did mention at the beginning that I want to swap this thing to a stick shift. I started evaluating my options, and started scouring yards. This is a good time to tell you all that I have a lot of experiences building Nissans and I love em as much as I like GM's. So, looking through the yards I couldn't find any camaros with stick pedals. I really don't like the idea of spending $500 for a spacer bracket to make F body pedals work, either, as I am in college on the GI bill and am broke! Also, when I took a brake pedal out of the yard and looked at the firewall.....

 

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Discussion Starter #3 (Edited)
Brake and clutch idea, continued.

I decided that there had to be a better factory solution. So I headed to the Truck section and took a gander at a Nissan Pathfinder. (WD21). These are very similar to the D21 hardbody, have the same pedal setups, were made over 10 years, are everywhere in the yards, and were much more common in a stick setup than the F body (or the Chevy trucks for that matter). On top of that, Nissan uses standard 3/16" double flared lines for thier clutch stuff, and they are made of aluminum, and come in many different bore sizes. The stuff is readily available at parts stores and the prices are similar to chevy stuff ( inexpensive:) ) .
I pulled the dash out and pulled these assemblies out.
Clutch (I love this offset!) I also like how the CLUTCH box is stronger than the GM brake pedal bracket. Wait till you see how beefy the brake box is!

Brake Box (and it is actually a BOX, not a flimsy stamped bracket I can bend with my hands easily like the GM part.....part of why our cars have such crappy brake feel imo)

GM pedal "box" on booster and rough guestimate of pedal height

Nissan pedal box on top of GM brake booster (I plan on either modding this to fit the GM booster or I will make a spacer to adapt to the Nissan bolt circle on the brake box) Look how close the top bolts are to lining up! If I drilled the nissan bracket holes to 3/8" like the GM bracket it would slide right on, just would have to mod the bottom. The GM clevis is actually attached to the nissan brake pedal (I will still mod the GM pushrod to use the nissan clevis, lol)


eyeball of clevis position on nissan pedal (approximately 1" above firewall if spacer is used)

I believe that I can cut down GM pushrod about 1" and use nissan clevis. This might allow me to mod nissan box and bolt directly to firewall and maintain pedal height.

eyeball comparison with the stock GM bracket


Bottom of bracket, have to extend the nissan box a bit but have to open up the hole in the middle to clear the dust boot anyway



If I don't use a spacer I believe the clutch and brake will be level with the gas pedal :)

eyeballing approximate pedal positions


This would put the clutch box right where the convenience center bracket resides on the firewall......

but that's ok because the firewall is flat here and this is what the clutch box looks like.

I would have to cut the top bracket off the nissan box but then it will be nice and flat on top and will be compatible with the b body cowl :)
The clutch box is about 1" shorter than the brake box, too! (the nissan firewall kicks in the same way)

Tilton sells clutch masters that will fit this pattern if I cannot find a way to install a remote reservoir on the nissan one.
Input on this/suggestions are greatly apprecitated!
I will do some actual measuring tomorrow after school :)
Thanks for looking, updates coming soon.
 

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Did you swap the VSSs to make your speedo correct (reasonably). The VSSs are different for the different gears on the 3.23 vs. the 2.56 or 2.73. The drive gears are the same, so you just have to swap the VSSs (including the driven gears).
 

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Discussion Starter #5
Vss

Nope, got lucky. The olds had a 3.23 open reAr and caprice had 3.23 posi. Verified speedo with GPS app on my iPhone and it's within 2mph everywhere. Speedo reads slightly fast which is common In my experience with gm cars (both my parents gms are same way, speedo indicates 2mph fast; so no need to swap out vss till I swap in 4.10's :D
 

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If you put 4:10s in it, you will probably have to get a pulse modifier to correct the speedo. The driven gears are becoming difficult to find. If you are going to build a new rear with 4:10s you could cover a lot of your costs by selling the 3.23 complete rather than replace the gears in it. Building one on the bench is a lot easier, and will keep your down time to a minimum as well. The rears are easy to find, and a used one for rebuild is cheap.
 

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Discussion Starter #7 (Edited)
Gear swap

I can't adjust the ecu? I remember the gear swap stuff from the nissans that had electric speedos. I also remember a link detailing how to mod a nissan speedo head to read pulses differently, ( lots of nissan 240's out there running gm ls motors and t56's and using stock gauge clusters :) ). I wonder if the GM cluster can be modded the same way? The nissan mod involved soldering resistors onto the board. I will get extra cluster and see if it is possible to mod board with a trim pot to allow adjustment of speedo readout. I won't be doing the 4.10's for a little while, school first :) I probably will get another rear to build up as you said, it's awesome idea!
 

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You can not adjust the computer. The speedo counts the pulses, and displays the result.

The pulse modifiers are relatively cheap, and you can adjust for tire size, and gearing by flipping a couple of tiny switches. Once you have it, it makes everything easy. You splice it into the wiring from the VSS, and mount it under the dash where you can easily reach it.

It is a lot easier than trying to figure out what resistor to solder into the board. You also do not have to tear the whole dash apart every time you change something. The dash is rather fragile, and you do not want to R&R it any more than you absolutely have to.

Make it easy on yourself.
 

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Discussion Starter #9
Thank you! I will definitely do the pulse modifier box then. I do know how fragile the dash trim is on these, I just fixed mine and have to pull it off again as my auto climate control unit does not dim anymore since I put a CD player in. Now I know where that extra wire goes (to illumination). I will work on adapting the nissan pedals for now, can you tell me what electronics are in that area? I know about the convinience center which I must relocate and the ABS controller (which I will eliminate) but not sure what is contained in the black box above it. I'm assuming the air bag module and check relay? If that is the case I will eliminate that as well since I have a friend with a nice cutlass sport wheel that will dress up my cruiser nicely. All this stuff needs to be relocated so I have room for the nissan clutch pedal box. Thank you again for all the good advice!
 

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It is either the DERM, or a resistor module. It could also be the daytime running lights dropping diode. It depends on which system you have. If you have twilight sentinel, you should not have the diode module.

My 92 has an alarm module in that area as well. It is a black box.
 

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Discussion Starter #11
Nissan brake pedal swap

Well it was a busy day at school but I managed to get a few ballpark measurements. I have decided to modify the nissan pedal bracket by extending it 2" and making it a bolt on deal. Spacer is not feasible due to the similarity of the bolt circles (about 3/8" different). Plus, the clutch box is the same length as brake box; about 9-1/4" (gm bracket about 11"). It still looks easy to adapt with my 110v mig welder and some steel ;) . I will post pics of the process tonight. I have to finish up a project for ceramics class this am then I am free to do the brake pedal. I will keep you guys posted.
 

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Discussion Starter #12
Nissan Brake pedal adaptation....

Welp this morning I went to school and finished my coil pot, and threw a few cylinders so I have something to do in class. I then came home and decided to work on the nissan pedal stuff. Here are some pics of measurements but I'm not gonna get technical on that because I decided to modify the pedal box to be a bolt-in to my car.
Nissan pedal bracket (firewall mounting)



Gm pedal bracket (firewall mounting)



GM bracket overall length

Nissan bracket overall length

GM brake pedal pivot point to clevis pin

Nissan brake pedal pivot pin to clevis (1" shorter, which I hope will make the brakes less grabby, lol)

Making the base plate

Finished base plate (still trimmed center hole a bit)

New base plate on Booster

Drilling out spot welds to remove Nissan base plate

Nissan base plate removed

and...I'm allowed 15 pics so on to the next post!
 

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Discussion Starter #13 (Edited)
Nissan Brake pedal adaptation....

Onward with the pic show. Let the modification begin (and may the odds forever be in my favor :) )
Making sure the angles line up somewhat on cowl side


Have to fill this gap in order to keep geometry with stock GM booster pushrod

Removing GM clevis pin from GM brake pedal

Drilled out clevis pin hole in nissan brake pedal and checked to see that everything will indeed line up.


Gm clevis pin ready to be welded into Nissan Brake pedal


The fun starts now :)

Top view after putting on a couple of tack welds (I'm using part of the stock GM bracket as well...this thing is gonna be STRONG even if my welds aren't the best in the world lol....)

Closing in the gaps with 1/8" steel

 

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Discussion Starter #14
Finishing up the nissan brake pedal box modification

Almost done!

Welding in the GM switch bracket so I can use my stock B body brake and cruise control switches



Cleaning it all up a bit

Ready to go...need some nicer weather to try it out in the car.

I think I can just drill a hole in the middle and it will just bolt right into my olds.


I apologize for the silly looking weld. I wanna make sure that brake clevis pin doesn't come out!


Onward to the clutch box. Just have to remove this bracket.

Bracket removed.

Guestimate of approximate pedal box positions. This should place the clutch master just to the left of the brake booster.

 

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Discussion Starter #15
Clutch and brake pedal offset!

Wanted to end the last post with this pic....

but hit my limit of 15. So had to do it this way.
Gonna get ready for Thanksgiving now, going to Harrisburg tomorrow. Stay warm, everyone and I wish you all a very delightful thanksgiving. Hopefully Friday I will be able to take some pics of installing this setup into my Oldsmobile. The pedal bracket is so much stronger than the stock one the brakes should feel completely different. Update soon!
 

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Discussion Starter #18
@ghettowagon: hey, thanks! Where did you get the grass guzzler bumper sticker? I think it would be a great gift for my mom this christmas ( at least one of em). She drives a tahoe and owns two horses...
 

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Discussion Starter #19
Nissan Brake pedal adaptation....

Well guys managed to get some time to work on the car, in between working on my final art project. Here I am getting some of that stuff together before tearing into the car.


The torso shape is a leftover from when I built it for a friend's individual studio project last year. She and I don't talk anymore because she went back to her uber possessive boyfriend and she doesn't wanna make him uncomfortable. I kept this, and the gears she had made (otherwise she would have thrown them away)
Now...on to what you're really hear for. I started tearing the car apart and decided to make it a grand ole' write up. So, I began by removing the lower dash trim (2- 7mm headed screws)

2) I then removed the lower dash brace (4- 10mm headed bolts)

3) I then pulled the brake and cruise control switches out of the brake pedal bracket (they just pull out, and disconnected the brake light wire from them so my battery wouldn't go dead)

4) I then removed the lower steering column brace (4- 10mm headed bolts)

5) I next removed the two phillips head screws from the firewall side of the ABS module...

and then pulled back the clip on the dash side to pull the connector off.

6) I then removed the 10mm headed bolt on the dash side that holds the module in, and removed it.



7) I then removed the two 7-mm head screws in the convenience center and the one 7mm screw that secured the twilight sentinel relay and pulled them out of the way.

8) I then removed the three 10mm nuts that held the Air Bag module in, disconnected it, and removed it.

9) I then broke out the plastic tray that these mounted to (I tried to unclip it but it's like 20 degrees F out here and it broke. I can't use it anyway :)

10) I then removed the two 7mm screws, unplugged the chime module, and set it aside.

10) I then cut out all the firewall insulation to the left of the steering column and brake pedal assembly.
 

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Discussion Starter #20
Nissan Pathfinder Brake and clutch install write up, continued

11) I then lowered the steering column (2- 15mm headed nuts)

12) I then removed the upper steering column brace (1- 13mm headed bolt)--it's under the column in the middle, refer to the pic of the brace after I removed it

13) I then removed the brake pedal assembly (4- 15mm headed locknuts at the firewall and one 13 mm headed bolt at the dashboard end of the bracket, plus the cotter pin that holds the booster pushrod on


14) Now it is time to test fit my Nissan brake pedal box!

15) Love the pedal placement :)

16) It bolted in just like the old one, awesome (ok i admit it, I had to do some filing, drill a new hole, and move the clip over half an inch, I had a little warpage from all the welding). I also removed the reverse light switch from the lower steering column as it was in the way at this point. It fit right back in after I installed all the braces and bolts.

17)I had to trim the upper column brace as the nissan brake box is wider than the GM brake bracket

18) Brake, cruise control, and reverse switches back where they are supposed to go.

19) I then pulled off the steering wheel because I am having trouble with my shift lock, so I am removing it. I won't have a shift lock anymore but it doesn't matter because by the time that will matter for inspection it will be stick. I also took the opportunity to remove the air bag wiring since the module won't be going back in.

20) I then removed the convenience center bracket, and did a trial fit of the clutch pedal box. The spot welds didn't want to let go and I tore up the firewall a bit, but I have a welder so its all good.


21) Due to the way the cowl is shaped, I have to mount the clutch box lower than the brake box, so until I shorten the clutch pedal (tomorrow!) the pedal heights are different. Keep in mind that I haven't drilled the holes in the firewall yet so the clutch pedal can still move toward the firewall about 2 inches.


22) Mounted into firewall (it's coming back out, still have a lot to do!)


Clutch pedal stops about 3/4" above the floor, gonna have to make a stop (or get the one out of the pathfinder and adapt it)


23) Gonna have to modify the clutch pedal box due to having to mount it lower.


Continued next post!
 
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