Rack Mounting Dilemma

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Rack Mounting Dilemma

Postby Rickracer » Tue Jul 05, 2011 4:47 pm

Ok, I've got a nice short rack, (Sweet Manufacturing) 18.25" from inner tie rod to inner tie rod, and 6" of stroke. My problem is that, with the rack centered in the chassis, the input (pinion) shaft points right at a header tube. If I move it over just a bit, I have a nice line of sight to a u-joint. I could shorten one tie rod and lengthen the other to accomplish this, but I'm not sure what it will do to bump steer. My other option is to abandon this rack and find something with the pinion in a little better position.

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Rickracer
ASE Master Auto Technician, 36+ years
'76 Vega Notchback, Twin Turbo 355/TH350 (soon to be a Powerglide w/Brake), 4 link, Koni Coilovers, 3.50 geared 9" w/Spool & Moser Axles, drag only, best all motor 1/8 mile pass to date, 6.90@99mph, 6.57@107.0 on a 60 shot, Best 1/4, 9.66@139.78, still tuning...
Project Album: http://s68.photobucket.com/albums/i4/Ri ... 20Begins/'
93 S10 RCSB, Hyd. Roller Vortec head 363 ci SBC, 2800stall lockup 700R4, LS Front Brakes, Narrowed F*rd Exploder 8.8 disc brake 3.73 posi rear, 8.0s@89 mph, (all motor, haven't sprayed it yet...)and tows the Vega to the track too
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Re: Rack Mounting Dilemma

Postby speedphreake » Wed Jul 06, 2011 6:33 am

To keep that rack, you will need to move the header tube. If you offset the rack, I'm pretty sure you will wind up with all sorts of steering issues. Is there any way to make the rack longer?
71 Vega hb
11 2500HD duramax
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Re: Rack Mounting Dilemma

Postby overkillrc » Fri Aug 12, 2011 1:55 am

making the rack longer would just move the tie rods out some (which may cause more problems with bumpsteer) the pinion would land in the same spot. i would want to center it and move the header tubes.
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Re: Rack Mounting Dilemma

Postby spencerforhire » Fri Aug 12, 2011 7:18 am

If you move the rack mount forward an inch or so and rotate the rack upward so the input spline points more straight up, you might be able to miss the header tube. You would probably have to add an extra u-joint to your steering shaft.
Personally, I'd just cut out the offending header tube and weld in a piece that curves around the steering.
The "fleet"-
77 Vega Estate wagon- project(someday)will have TPI305/T-5, S-10 spindles/axles
72 Vega HB Drag Car -383/'Glide/9"(9.35@146.19)(5.94@117.28 1/8th)
76 Vega GT- 400/4spd/9" retired from active duty(rusty)
03 Silverado 2WD ex.cab (work truck/parts hauler)
04 Silverado 2WD ex.cab (retired)
06 Haulin' 20ft enclosed car transporter
93 Suburban- 350/4L60(retired)
00 Saturn SW2- wife's car
01 Saturn SC2- younger son's project
00 Saturn SL2- daughter's car
98 Saturn SW2- spare
and 3 more Saturn "parts cars"
Note- the very act of listing all of these has made me realize I have some kind of problem.....

Visit http://www.spencerforhire.ca
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Re: Rack Mounting Dilemma

Postby Rickracer » Fri Aug 12, 2011 9:42 am

I wound up sliding it over just a bit and rotating it up a little bit. It came out good, it remains to be seen how well it will steer, but it's smoother now than it's been since I got the car.

Image

Image

I've got a good pic of the whole system with the motor out, but I haven't uploaded it yet. 8)
Rickracer
ASE Master Auto Technician, 36+ years
'76 Vega Notchback, Twin Turbo 355/TH350 (soon to be a Powerglide w/Brake), 4 link, Koni Coilovers, 3.50 geared 9" w/Spool & Moser Axles, drag only, best all motor 1/8 mile pass to date, 6.90@99mph, 6.57@107.0 on a 60 shot, Best 1/4, 9.66@139.78, still tuning...
Project Album: http://s68.photobucket.com/albums/i4/Ri ... 20Begins/'
93 S10 RCSB, Hyd. Roller Vortec head 363 ci SBC, 2800stall lockup 700R4, LS Front Brakes, Narrowed F*rd Exploder 8.8 disc brake 3.73 posi rear, 8.0s@89 mph, (all motor, haven't sprayed it yet...)and tows the Vega to the track too
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Re: Rack Mounting Dilemma

Postby spencerforhire » Fri Aug 12, 2011 10:45 am

Offsetting the rack on a race-only car is no problem; is there enough travel left to let the spindles contact the stops on the lower control arms? Worst case is it just means the car will turn tighter in one direction than the other.
The "fleet"-
77 Vega Estate wagon- project(someday)will have TPI305/T-5, S-10 spindles/axles
72 Vega HB Drag Car -383/'Glide/9"(9.35@146.19)(5.94@117.28 1/8th)
76 Vega GT- 400/4spd/9" retired from active duty(rusty)
03 Silverado 2WD ex.cab (work truck/parts hauler)
04 Silverado 2WD ex.cab (retired)
06 Haulin' 20ft enclosed car transporter
93 Suburban- 350/4L60(retired)
00 Saturn SW2- wife's car
01 Saturn SC2- younger son's project
00 Saturn SL2- daughter's car
98 Saturn SW2- spare
and 3 more Saturn "parts cars"
Note- the very act of listing all of these has made me realize I have some kind of problem.....

Visit http://www.spencerforhire.ca
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Re: Rack Mounting Dilemma

Postby Rickracer » Fri Aug 12, 2011 3:02 pm

It turns far enough both ways to make the tire touch the header tube, :? :lol: 8)
Rickracer
ASE Master Auto Technician, 36+ years
'76 Vega Notchback, Twin Turbo 355/TH350 (soon to be a Powerglide w/Brake), 4 link, Koni Coilovers, 3.50 geared 9" w/Spool & Moser Axles, drag only, best all motor 1/8 mile pass to date, 6.90@99mph, 6.57@107.0 on a 60 shot, Best 1/4, 9.66@139.78, still tuning...
Project Album: http://s68.photobucket.com/albums/i4/Ri ... 20Begins/'
93 S10 RCSB, Hyd. Roller Vortec head 363 ci SBC, 2800stall lockup 700R4, LS Front Brakes, Narrowed F*rd Exploder 8.8 disc brake 3.73 posi rear, 8.0s@89 mph, (all motor, haven't sprayed it yet...)and tows the Vega to the track too
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1976 Chevrolet Vega

Re: Rack Mounting Dilemma

Postby chevy art » Fri Aug 12, 2011 7:01 pm

sounds likem you are ready to be up and running. good luck rick art
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Re: Rack Mounting Dilemma

Postby Rickracer » Sat Aug 13, 2011 8:11 am

It's moving along pretty good, been painting the rear subframe the last few evenings, pulled the rear end out last night to get in all the nooks and crannies and paint all the freshly welded spots on the housing as well as the 4 link parts, shock mounts, and track locator. Today I'm gonna finish all the front floor metal work, blow out all the metal dust and paint the floorboards. I might try to go get a sheet of aluminum today too, if they are open, rear tinwork is the next big hurdle, that and the wheel tubs and I can start reassembling. 8)
Rickracer
ASE Master Auto Technician, 36+ years
'76 Vega Notchback, Twin Turbo 355/TH350 (soon to be a Powerglide w/Brake), 4 link, Koni Coilovers, 3.50 geared 9" w/Spool & Moser Axles, drag only, best all motor 1/8 mile pass to date, 6.90@99mph, 6.57@107.0 on a 60 shot, Best 1/4, 9.66@139.78, still tuning...
Project Album: http://s68.photobucket.com/albums/i4/Ri ... 20Begins/'
93 S10 RCSB, Hyd. Roller Vortec head 363 ci SBC, 2800stall lockup 700R4, LS Front Brakes, Narrowed F*rd Exploder 8.8 disc brake 3.73 posi rear, 8.0s@89 mph, (all motor, haven't sprayed it yet...)and tows the Vega to the track too
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1976 Chevrolet Vega

Re: Rack Mounting Dilemma

Postby highstrungvega » Fri Aug 26, 2011 10:33 pm

Hope everything is coming together for you!
72 Coupe
71 Notchback selling
2013 Ford F150XLT company work truck
You learn more from doing it wrong the first time!
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Re: Rack Mounting Dilemma

Postby Rickracer » Sat Aug 27, 2011 10:22 pm

It's going pretty good. Somewhere in this thread: viewtopic.php?f=20&p=200235#p200235 , there are pics of everything, including the whole system with the motor out, :th: 8)
Rickracer
ASE Master Auto Technician, 36+ years
'76 Vega Notchback, Twin Turbo 355/TH350 (soon to be a Powerglide w/Brake), 4 link, Koni Coilovers, 3.50 geared 9" w/Spool & Moser Axles, drag only, best all motor 1/8 mile pass to date, 6.90@99mph, 6.57@107.0 on a 60 shot, Best 1/4, 9.66@139.78, still tuning...
Project Album: http://s68.photobucket.com/albums/i4/Ri ... 20Begins/'
93 S10 RCSB, Hyd. Roller Vortec head 363 ci SBC, 2800stall lockup 700R4, LS Front Brakes, Narrowed F*rd Exploder 8.8 disc brake 3.73 posi rear, 8.0s@89 mph, (all motor, haven't sprayed it yet...)and tows the Vega to the track too
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Location: Kissimmee, Florida

1976 Chevrolet Vega


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