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-   -   Front Disc brake upgrade kit (https://67-72chevytrucks.com/vboard/showthread.php?t=841743)

samert111 01-29-2023 11:47 PM

Front Disc brake upgrade kit
 
Looking at upgrading my 68 C10 front brakes to disc and 2.5" drop spindles too. I'm considering the CLP-6370SWBK6OE kit from Summit to keep the current 6 lug configuration for my wheels. I already have power brakes but will need a new MC for the front disc and also a proportioning valve. I'm seeing MC's with both 1" and 1.125" bores. Which one do I need or doesn't really matter?

If there's better kit that possibly has all the components I need all in one package, please make suggestions.

Accelo 01-30-2023 10:38 PM

Re: Front Disc brake upgrade kit
 
If you are using the stock wheels you have to be very careful when converting as the caliper takes up a lot more room than the drums. What for the center hub also, it's 3.025.
Read all the reviews, some are complaining bout hoses that are too long. The lowering spindle relocates the caliper so "stock" isn't going to always be correct on a lowered truck. Took me three hoses to get ones that I thought were safe. Others complained bout having to purchase upper control arms when they couldn't get the alignment. Once you get this far you are buried in it and typically can't go back.
The factory disc brakes connect the flexible line to the hard line in front of the spindle and with drums at the rear. You can convert to discs and have the line go either way but it is much easier to connect to the rear factory drum location. Which is what most kits do. Also a somewhat untested run for the flex hose. The brake lines were incorrect sized at the fittings and did not fit to existing hard lines on the truck. I am quoting several buyers "I would advise anyone to double check that so you don't end up with a down truck due to lines."

Some customers said everything worked perfectly. For me, I fought the brakes and the brakes won. Well I eventually did get it but it was a long and extended hassle. Getting the brake lines from the MC to the cross-member was hell for me. I now have a $250 hydraulic flaring tool that I needed to fix the "plug and play" lines I purchased. I recommend going with steel line for the first timers.

Some board members report a plug and play system. Hopefully, some will give you some feedback. I am suspicious by nature and rarely disappointed by resellers.
Cheers

samert111 01-31-2023 09:13 AM

Re: Front Disc brake upgrade kit
 
Quote:

Originally Posted by Accelo (Post 9173243)
If you are using the stock wheels you have to be very careful when converting as the caliper takes up a lot more room than the drums. What for the center hub also, it's 3.025.
Read all the reviews, some are complaining bout hoses that are too long. The lowering spindle relocates the caliper so "stock" isn't going to always be correct on a lowered truck. Took me three hoses to get ones that I thought were safe. Others complained bout having to purchase upper control arms when they couldn't get the alignment. Once you get this far you are buried in it and typically can't go back.
The factory disc brakes connect the flexible line to the hard line in front of the spindle and with drums at the rear. You can convert to discs and have the line go either way but it is much easier to connect to the rear factory drum location. Which is what most kits do. Also a somewhat untested run for the flex hose. The brake lines were incorrect sized at the fittings and did not fit to existing hard lines on the truck. I am quoting several buyers "I would advise anyone to double check that so you don't end up with a down truck due to lines."

Some customers said everything worked perfectly. For me, I fought the brakes and the brakes won. Well I eventually did get it but it was a long and extended hassle. Getting the brake lines from the MC to the cross-member was hell for me. I now have a $250 hydraulic flaring tool that I needed to fix the "plug and play" lines I purchased. I recommend going with steel line for the first timers.

Some board members report a plug and play system. Hopefully, some will give you some feedback. I am suspicious by nature and rarely disappointed by resellers.
Cheers

Thanks for the feedback Accelo. I'll certainly need to investigate everything you brought up. Hopefully Summit will have answers to your points.

67C10Step 01-31-2023 11:03 AM

Re: Front Disc brake upgrade kit
 
1 Attachment(s)
The brake system on my truck started out with one plan and ended up a total replace. All new hard lines from Inline tube. In the front I retained the hard lines on the rear of the crossmember. I didn't see the need to go four wheel disc on my build so just converted to power with disc up front. Drop spindles, calipers, and six lug rotors are all CPP through Summit. I've read much negative feedback on CPP but mine all went together without any problems.
For the flex line up front I used lines suggested by Grumpy Old Man in a thread. Duralast part number 88207, they are listed for a 1969 Buick GS. Took a little filing on the end that goes into the frame tab to get it to fit well but nothing out of the expected.

Grumpy old man 01-31-2023 11:50 AM

Re: Front Disc brake upgrade kit
 
3 Attachment(s)
This video will help , The inline tube stainless brake line fit great , if your going to upgrade your brakes to disc/drum Start by rebuilding your rear drums first and work forward ,rear shock locators , parking brake cables from rock auto , brake lines from inline tube , brake master from inline / CPP . Moog front suspension parts from Rock auto I ordered the CPP 2 1/2 drop spindles and 6 lug rotors and calipers thru Summit for the fast free shipping . if your going to rebuild your braking system do it all at one time using parts that work together .

https://www.youtube.com/watch?v=y5q7uBQt_4g

67C10Step 01-31-2023 12:24 PM

Re: Front Disc brake upgrade kit
 
1 Attachment(s)
I followed Grumpy's road map almost exactly and to confirm that here is a rear frame photo.

samert111 01-31-2023 08:47 PM

Re: Front Disc brake upgrade kit
 
1 Attachment(s)
Thanks for all the feedback guys.

Fortunately, my truck has had a frame off restoration recently so all the brake lines and brake hoses are all newer.

My concern was if the current front hard brake lines are large enough to handle the increased flow/volume for the disc upgrade. So may need to upgrade those as necessary.

Secondly, the brake kit disclaimer says it will not work with factory 15" wheels but I have aftermarket aluminum wheels so I'll still need to take some measurements to confirm the calipers will clear my current wheels. (see pic)

I'm already power brakes but will need a new MC and proportioning valve for the front discs.

We're in Tucson for the winter heading back to MI in April so all I can think about what mods I want to make when I get home.

On the list first this summer is the drop spindle disc brake conversion along with 2" lower blocks in the rear and rear shock relocation kit from No limit Engineering to move the shocks to outside the frame rails and behind the rear diff.

Next would be swapping out the manual Saginaw 4 speed with a Tremec 5 speed manual with OD and converting the rear diff to a limited slip carrier changing the 3.08 gears to 3.73 and the rear tires to 295/50R15 from the current 235/70R15's.

Can't wait to get home.

Grumpy old man 01-31-2023 11:26 PM

Re: Front Disc brake upgrade kit
 
Quote:

Originally Posted by samert111 (Post 9173618)
Thanks for all the feedback guys.

Fortunately, my truck has had a frame off restoration recently so all the brake lines and brake hoses are all newer.

My concern was if the current front hard brake lines are large enough to handle the increased flow/volume for the disc upgrade. So may need to upgrade those as necessary.

Secondly, the brake kit disclaimer says it will not work with factory 15" wheels but I have aftermarket aluminum wheels so I'll still need to take some measurements to confirm the calipers will clear my current wheels. (see pic)

I'm already power brakes but will need a new MC and proportioning valve for the front discs.

We're in Tucson for the winter heading back to MI in April so all I can think about what mods I want to make when I get home.

On the list first this summer is the drop spindle disc brake conversion along with 2" lower blocks in the rear and rear shock relocation kit from No limit Engineering to move the shocks to outside the frame rails and behind the rear diff.

Next would be swapping out the manual Saginaw 4 speed with a Tremec 5 speed manual with OD and converting the rear diff to a limited slip carrier changing the 3.08 gears to 3.73 and the rear tires to 295/50R15 from the current 235/70R15's.

Can't wait to get home.

Don't do it , the 295/50/15 is only 26.6" tall vs the 27.95 tire you have now That combined with 2 " drop blocks will lower your scrub line ,Meaning if you have a flat the U bolts will dig into the pavement , Along with installing a 3.73 gear set your RPMS will climb on the interstate above 3000 , I'm not sure you can put 50 series tire on an 8" wheel . it's a vicious circle . :chevy:

https://www.tacomaworld.com/tirecalc...0r15-295-50r15

http://67-72chevytrucks.com/vboard/s...d.php?t=354644

https://spicerparts.com/calculators/...rpm-calculator

samert111 02-01-2023 07:01 AM

Re: Front Disc brake upgrade kit
 
Quote:

Originally Posted by Grumpy old man (Post 9173739)
Don't do it , the 295/50/15 is only 26.6" tall vs the 27.95 tire you have now That combined with 2 " drop blocks will lower your scrub line ,Meaning if you have a flat the U bolts will dig into the pavement , Along with installing a 3.73 gear set your RPMS will climb on the interstate above 3000 , I'm not sure you can put 50 series tire on an 8" wheel . it's a vicious circle . :chevy:

https://www.tacomaworld.com/tirecalc...0r15-295-50r15

http://67-72chevytrucks.com/vboard/s...d.php?t=354644

https://spicerparts.com/calculators/...rpm-calculator


Thanks Grumpy,
I may need to re-think the drop blocks and go with a drop spring instead. It's already close to the bump stops now so I think it's already been lowered some, I just don't know how much.

As for the engine RPM's at highway speeds, according to the calculator I'm using the, .72 final gear of the Tremec 5 speed would put me at just over 1800 RPM with the current 3.08 gear vs almost 2200 RPM with the 3.73 gear at 65 MPH.

It's the look of the wider 295 tire I'm looking for and yes, I probably will need to go with a wider wheel for it set right and not look like an inner tube on the current 8" wheels if it could even be done.

I may just keep the 3.08 gear once I get the Tremec installed and see how it performs and just go with the posi carrier.

It's all a work in process, but I'm having a great time with it.


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