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Old 10-21-2018, 05:08 PM   #1
sluggy
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Stopping After the swap

I have an ls3/6l80 combo in my 62 C20. Currently i have discs up font and drums in the rear.
Because I still have the original 62 front suspension, I have used Early classics C20 to C10 conversion spindles, and their disc kit on the front end. Running a vacuum assist master cylinder. I changed the rear end to a 12 bolt and am just running the stock drums on the rear.
I have had a couple of close calls where she just keeps rolling !! So I feel like I need better anchors.
Id be interested to hear what others are using ?
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Old 10-22-2018, 10:41 AM   #2
ls1nova71
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Re: Stopping After the swap

The set up you have should be pretty decent, but if it's not working right, are you sure its fully bled? If so, what size of vacuum booster are you running? I had a 7" dual diaphragm booster on my car that everybody said was the thing to use and it was terrible. I switched to a Hydroboost and its way better. Might be something to consider, although I don't know how hard they are to come by in New Zealand.
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Old 10-22-2018, 11:02 AM   #3
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Re: Stopping After the swap

I'm running a hydroboost setup with Wilwood's up front, and am in the process of converting my 12bolt to run D52's out back via Captain Fab's setup.

Even on disc/drum my truck stops pretty damn flat in a hurry, plenty to lock em up if needed.

I did randomly find out this weekend that my truck had a Wilwood 2lb anti-drainback valve in the front lines...never knew that before. Supposedly it helps with calipers that draw-back too far when the master is mounted low. Not sure if its helping me, but I'm keeping it in.
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Old 10-23-2018, 10:17 AM   #4
truckdude239
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Re: Stopping After the swap

Im rocking the stock non power brakes on my 71 disc /drum and it stops just fine something isnt right with your set up
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Old 10-23-2018, 12:08 PM   #5
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Re: Stopping After the swap

Brew, which master cylinder did you go with on your setup. I am using one from a hydro boost tahoe and think it is too large of diameter. I am looking to swap down a size. I believe mine is 1.25 diameter bore. I think I need a 1.125
Thanks
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Old 10-23-2018, 01:23 PM   #6
BR3W CITY
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Re: Stopping After the swap

I'm using the master that came off the hydroboost donor. ~96 astro
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Old 10-23-2018, 03:34 PM   #7
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Re: Stopping After the swap

Pedal feels solid, but i will give it another bleed anyway, booster is a 9" single diaphragm. There is no way I can get this to lock up though. I am running 20" detroit steel wheels, these things are heavy - approaching 55lbs per rim plus the tyre, Im pretty sure that doesnt help much. Ive got some 15" rims that i will try on it to see if that makes muh difference.
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Old 10-23-2018, 03:50 PM   #8
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Re: Stopping After the swap

Quote:
Originally Posted by sluggy View Post
I have an ls3/6l80 combo in my 62 C20. Currently i have discs up font and drums in the rear.
Because I still have the original 62 front suspension, I have used Early classics C20 to C10 conversion spindles, and their disc kit on the front end. Running a vacuum assist master cylinder. I changed the rear end to a 12 bolt and am just running the stock drums on the rear.
I have had a couple of close calls where she just keeps rolling !! So I feel like I need better anchors.
Id be interested to hear what others are using ?

I have CPP dropped spindles, '75 1/2 ton mc, dual diaphragm booster and a 65 12 bolt drum rear with no issues. Are you certain your torque converter is unlocking?
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Old 10-23-2018, 03:54 PM   #9
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Re: Stopping After the swap

Quote:
Originally Posted by BR3W CITY View Post
I'm using the master that came off the hydroboost donor. ~96 astro
Thanks I may give one a try.
Dave
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1968 Custom Chevy with turbo charged 5.3 gen III T56 six speed swap
1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
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Old 10-23-2018, 05:23 PM   #10
1971Stepside
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Re: Stopping After the swap

Dave, I have one off an astro you can have. It is missing a cap off the big reservoir.
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Old 10-24-2018, 10:29 AM   #11
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Re: Stopping After the swap

Thanks Shannon, we do need to get together.
Dave
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1968 Custom Chevy with turbo charged 5.3 gen III T56 six speed swap
1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
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Old 10-27-2018, 12:37 AM   #12
sluggy
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Re: Stopping After the swap

Quote:
Originally Posted by verdell View Post
I have CPP dropped spindles, '75 1/2 ton mc, dual diaphragm booster and a 65 12 bolt drum rear with no issues. Are you certain your torque converter is unlocking?
I think that is the issue. It feels like its driving through the brakes. I'll check the wiring to the trans and make sure I have it right.
Thanks for the suggestion !!
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Old 10-27-2018, 12:46 AM   #13
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Re: Stopping After the swap

Quote:
Originally Posted by sluggy View Post
Pedal feels solid, but i will give it another bleed anyway, booster is a 9" single diaphragm. There is no way I can get this to lock up though. I am running 20" detroit steel wheels, these things are heavy - approaching 55lbs per rim plus the tyre, Im pretty sure that doesnt help much. Ive got some 15" rims that i will try on it to see if that makes muh difference.
I am interested how much of.a diffirence the 15" rims make in stopping. I have been looking at the Detroit wheels but the weight was my concern..
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Old 10-27-2018, 10:34 PM   #14
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Re: Stopping After the swap

Quote:
Originally Posted by BR3W CITY View Post
I'm running a hydroboost setup with Wilwood's up front, and am in the process of converting my 12bolt to run D52's out back via Captain Fab's setup.

Even on disc/drum my truck stops pretty damn flat in a hurry, plenty to lock em up if needed.

I did randomly find out this weekend that my truck had a Wilwood 2lb anti-drainback valve in the front lines...never knew that before. Supposedly it helps with calipers that draw-back too far when the master is mounted low. Not sure if its helping me, but I'm keeping it in.
Im still running 15 wheels. Will Wilwoods fit or do you have larger diameter wheels?
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Old 10-28-2018, 11:52 AM   #15
BR3W CITY
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Re: Stopping After the swap

That really depends on the wheel. My M/T front wheels clear them, and my Holeshot rears clear them, but my older Diamond's would be uncomfortably close.
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Old 10-29-2018, 10:32 AM   #16
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Re: Stopping After the swap

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Originally Posted by 1970 CST Short Wide View Post
Im still running 15 wheels. Will Wilwoods fit or do you have larger diameter wheels?
I have the Wilwoods D52 replacement on the front and they will not clear my old 15 inch aluminum wheels. It is close but there is a slight rubbing.
I have converted to an aftermarket spindle so that may have a little affect?
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1967-71 GMC 3/4 ton long step 4x4 (not sure what year exactly?)
"A good friend will bail you out of jail...but a true friend will be sitting next to you saying "that was frekin awesome".
"If it doesn't fit force it...If it breaks then it needed to be replaced anyway!"
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