Question for the hydroboost conversion folks.

[agp23109]

Anyone know if the fluid resivor from a stock 1 1/8 master cylinder will fit on an 1 5/16 master cylinder found on the super duty?

 

[icanfixall]

Nope... Don't know but its a good question to find the answer to... I'll be watching this thread.

 

[RLDSL]

I just did the swap, if I can remember where the heck I tossed the old MC I'll measure the thing. It's laying around here somewhere.

 

[paulb3]

From what I have read not sure where the article is but reusing the original master cylinder requires that the mounting holes be elongated/sloted a bit to fit.

 

[Alex S]

From what I have read not sure where the article is but reusing the original master cylinder requires that the mounting holes be elongated/sloted a bit to fit.

this is correct which takes 5 minutes with the die grinder

 

[RLDSL]

THats not what he was asking. HE was wanting to know if the plastic tank from the original MC would push into the holes of the replacement SD sized MC. Some new and rebuilt master cylinders are sold without the plastic tanks.

That said, a brand spanking new SD size MC with a new plastic tank is only around $28

 

[agp23109]

THats not what he was asking. HE was wanting to know if the plastic tank from the original MC would push into the holes of the replacement SD sized MC. Some new and rebuilt master cylinders are sold without the plastic tanks.

That said, a brand spanking new SD size MC with a new plastic tank is only around $28

Where did you get one for $28? I have an 1 5/16 mc but no resivor. A quick eyeball check of the 1 1/8 tells me no go. Autozone tells me its a dealer item and the stealersship wants $94.00 for JUST the resivor cheaper at this point to get a mc with a resivor.

And for clarification im currently running hydroboost with 1 1/8 mc and although it's better than the vacuum booster I think there's more to be had with the 1 5/16 mc. I'll keep you posted with the results for anyone considering the swap or who's done it and stayed with the 1 1/8 mc like I did.

Thanks for all the replies

 

[RLDSL]

Where did you get one for $28? I have an 1 5/16 mc but no resivor. A quick eyeball check of the 1 1/8 tells me no go. Autozone tells me its a dealer item and the stealersship wants $94.00 for JUST the resivor cheaper at this point to get a mc with a resivor.

And for clarification im currently running hydroboost with 1 1/8 mc and although it's better than the vacuum booster I think there's more to be had with the 1 5/16 mc. I'll keep you posted with the results for anyone considering the swap or who's done it and stayed with the 1 1/8 mc like I did.

Thanks for all the replies

I got it at advance. I thought it was a rebuilt and brought the core back and me guy tells me it was NEW
I will try to find the thing later or at least in the next day or so. Had a minor disaster in the shop. Had a toolbox fall over and it's a mess out there ( ground shifts a lot here )

 

[towcat]

Where did you get one for $28? I have an 1 5/16 mc but no resivor. A quick eyeball check of the 1 1/8 tells me no go. Autozone tells me its a dealer item and the stealersship wants $94.00 for JUST the resivor cheaper at this point to get a mc with a resivor.

And for clarification im currently running hydroboost with 1 1/8 mc and although it's better than the vacuum booster I think there's more to be had with the 1 5/16 mc. I'll keep you posted with the results for anyone considering the swap or who's done it and stayed with the 1 1/8 mc like I did.

Thanks for all the replies

if you can make the drive down to santa clara, I have a couple of used hydro master cylinders with the reservoirs still attached.

 

[agp23109]

if you can make the drive down to santa clara, I have a couple of used hydro master cylinders with the reservoirs still attached.

Thanks for the offer but with fuel prices the way they are it's cheaper to just return my resivorless mc and buy one with a resivor. The difference is only $10 or $15. Thanks again though.

 

[RLDSL]

Thanks for the offer but with fuel prices the way they are it's cheaper to just return my resivorless mc and buy one with a resivor. The difference is only $10 or $15. Thanks again though.

I was sitting at the parts counter wondering if my f350 one would fit and my friend standing on the other side reminded me that the old one would most likely break trying to get it removed from the old MC anyway , and for the scant few bucks difference between one with a tank and one without, I just got the one with the tank.

 

[agp23109]

Decision made. Buying a new mc with resivor for $60. Problem solved. Thanks for all the help. I'll update the thread with the difference between the two mc once I swap them out.

 

[agp23109]

Swapped master cylinders today. And YES the master cylinder makes a difference. Huge difference between the two. Anyone considering the swap should not even waste their time with the stock master cylinder. Just bite the bullet and get the 1 5/16 mc to get the full potential out of the hydroboost swap. Thanks for all the replies!

 

[oldblue05]

Don't mean to hijack but I'm gonna do this conversion sometime and was wondering which pump and bracket I need; I know it's a saginaw, if someone could just post a link from rockauto or something that would be great. I know they have em in salvage yards but would rather get a new one and not have any reliability issues.

 

[franklin2]

Swapped master cylinders today. And YES the master cylinder makes a difference. Huge difference between the two. Anyone considering the swap should not even waste their time with the stock master cylinder. Just bite the bullet and get the 1 5/16 mc to get the full potential out of the hydroboost swap. Thanks for all the replies!

What type of difference was it? In theory, the larger master cylinder bore will give you less pedal travel, and also less pressure. But the hydroboost might overcome the less pressure. Some smart people designed this system, so I would suspect it would work better as designed, just curious what you found out.