5-lug conversiosn-looking for advice, Putting on the PMB group buy 5 lug hub conversion Options

[DRPHIL914]

I am finally getting around to doing this, i am wondering who else has done this and whether you have any words of wisdom, etc.

One thing to know, I have newly re-done trailing arms, with the new hubs and bearings already installed, also new pivot shafts and bushings as well -

this week i was able to order my newly reman. calipers from PMB, so "while i am at it" is the catch phrase to use here i think, i also had them send me new brake hoses and master cylinder(mine just went bad, so i have not been able to drive the car).

So i have not seen anyone else that did this group buy post any thread or pictures on this process, so i figured i would do this when i get started, but would appreciate the advice! I have done brakes on many other vehicles but not my 914

here is what i already have done -
-new shocks and springs- rear: sport bilistein's with 100#springs, new factory anti-roll bar bushings.

thanks Eric and Bill H. for getting the group buy put together, and Eric for the ONE-STOP-SHOP and providing all the necessary components!!!!.

Phil

[Luke M]

Hi Phil,

How's things?
This is pretty straight forward as far as install goes.
Go to Eric's website and look at his videos on the install.
You may need to find some threaded rod and some large washers to install the hubs.
Otherwise easy to do.

Take care,

[DRPHIL914]

Hi Phil,

How's things?
This is pretty straight forward as far as install goes.
Go to Eric's website and look at his videos on the install.
You may need to find some threaded rod and some large washers to install the hubs.
Otherwise easy to do.

Take care,

Luke,

going good, been finishing a bathroom remodel, so next week i should be on top of this, getting ready to order tires, the calipers from eric came saturday, and new MC came today. so i almost set. I had the rear hubs and bearings installed into newly finished rear trailing arms by Eric, also new bushings and pivot shaft so that should be pretty easy. I will take a look at the Video, and Eric just sent me a link to his thread on setting the venting/clearance.

How's your six conversion going? did you put the new rims on yet? I have been doing a little self polishing on the outer rims, seem to be cleaning up nicely. I will post a pic once i paint the pedals!.

Phil

[lsintampa]

If you use stock rear calipers, you are going to have to shave a bit off of the rotors so they fit.

I went through this very conversion and it was really straight forward. Used the bolt on parts from Eric, for the front - they just bolt on - stock calipers not an issue.

The only problem I ran into was the rear rotors with stock calipers. Just have a machine shop take like 2mm off or as needed.

[Jeffs9146]

Just have a machine shop take like 2mm off or as needed.

(IMG:style_emoticons/default/agree.gif)

Just to be clear it is 2mm off the diameter! I took it the a brake shop and they were able to set up there machine to cut off the end of the rotors!

[DRPHIL914]

Just have a machine shop take like 2mm off or as needed.

(IMG:style_emoticons/default/agree.gif)

Just to be clear it is 2mm off the diameter! I took it the a brake shop and they were able to set up there machine to cut off the end of the rotors!

gotcha, thanks for the heads up. We have a local porsche shop, specializes in all things aircooled- they just did BillH1963's new /6 conversion engine work. I'm sure they will be able to help out if i have any fitment issues. I was orginally going to to a caliper upgrade but i talked it over with Eric(PMB) and really did not seem to make since, so i stayed with the stock set up stock calipers and new pads , new 19mm master cylinder will go in as well, and if i get it all set up right, i don't think i will have any issues stopping ability (IMG:style_emoticons/default/smile.gif)

[Eric_Shea]

Ummmmmmmmmmm...

Les bought 914-6 rear rotors.

The people in the group buy have 914-4 rear rotors that were machined to 5x130.

***DO NOT MILL ANYTHING OFF YOUR ROTORS***

[Jeffs9146]

Ummmmmmmmmmm...

Les bought 914-6 rear rotors.

The people in the group buy have 914-4 rear rotors that were machined to 5x130.

***DO NOT MILL ANYTHING OFF YOUR ROTORS***

Just to be clear sometimes the 914-6 original rotors will need to be milled and sometimes they won't! It depends on which rear calipers you have or where you purchased the rotors. Some kits for the "conversion" would have come with pre-milled rotors. The 4 rotors that were machined will NOT need to be milled!

If I didn't mill anything off my 914-6 rotors then my new calipers that I purchased from you wouldn't have fit!

I have had calipers that did fit with the 6 rotors but when I pulled off my old ones that did fit and replaced them with the ones I purchased from you, they didn't fit!

I had two choices,

1. Call you and try to convice you that they don't fit or
2. Mill 2mm off the rotor and call it a day!

I chose option 2 since I had someone to do the milling for free!

[Eric_Shea]

Kinda aware of all that. 914-6 rotors need to be milled. 911 rotors need to be milled.

[Eric_Shea]

Oh, I forgot to add these !!!

[lsintampa]

Ummmmmmmmmmm...

Les bought 914-6 rear rotors.

The people in the group buy have 914-4 rear rotors that were machined to 5x130.

***DO NOT MILL ANYTHING OFF YOUR ROTORS***

Yeah, my bad... I did buy 914 / 6 rotors and those needed 2mm taken off.

If you buy 914 / 4 rotors you need them machined as noted.

Sorry for any confusion.

Len

[Chris H.]

Ummmmmmmmmmm...

Les bought 914-6 rear rotors.

The people in the group buy have 914-4 rear rotors that were machined to 5x130.

***DO NOT MILL ANYTHING OFF YOUR ROTORS***

OK so I don't need to do anything at all to my rear rotors then? From 4 lug to 5 lug conversion group buy?

BTW Eric I think you'll be getting some calipers to rebuild very soon. The rears are looking very ratty.

[lsintampa]

Ummmmmmmmmmm...

Les bought 914-6 rear rotors.

The people in the group buy have 914-4 rear rotors that were machined to 5x130.

***DO NOT MILL ANYTHING OFF YOUR ROTORS***

OK so I don't need to do anything at all to my rear rotors then? From 4 lug to 5 lug conversion group buy?

BTW Eric I think you'll be getting some calipers to rebuild very soon. The rears are looking very ratty.

IF you keep your stock calipers you need to choose to have stock rotors drilled for the 5-lug pattern, or buy 914/6 rotors and have them milled.

[Chris H.]

Got it. The rotors in the group buy were redrilled 4 lug so we should be good.

[Eric_Shea]

Some Further Edification:

There's a couple ways to go to get a 5x130 rotor on the back of a 914 and, there are a lot of fit issues with each. The choice is usually predicated upon price and caliper selection.

If you are using stock 914-4 calipers with modified 914-4 hubs the choice should be a 914-4 rear rotor drilled to the 5x130 specs. with care given when indexing to retain the 2 chamfered mounting holes. The reasons being:

1. Your 914 hubs have these mounting holes machined into them and hopefully, they were also indexed to retain them. On our "group buy" the hubs and 914 rear rotors were both indexed to match and the mounting holes were retained.

2. You're going to have to machine either rotor so you might as well machine the less expensive 914-4 rotor to 5x130 vs. machining the expensive 914-6 rotor to the proper diameter

If you are using 911 rear hubs (as the 914-6 did) and stock 914-4 calipers, then you should probably get the 914-6 rotors and have them machine the diameter to match the 914-4 diameter. This involves shaving 2mm off the edge or 4mm off the total diameter. Because:

1. You will not have to machine two new rotor mounting screws into your 911/914-6 hubs.

2. You will not have to machine the rotor to 5x130. With both of those bits of machining needed, it would probably be a wash in price for the 914-4 rotor and the 914-6 rotor with minimal machining needed.

Obviously, 914-6 calipers and 914-6 rotors will mate right up. 914-6 rotors and 911 rear calipers will also mate up.

Here's another element of surprise:

If you want to move to a vented rear rotor (911 is about the only one available), then you will need to:

1. Take 4mm off the diameter if you are using a spaced 914-4 caliper "and" put 4.5 to 5mm spacers under the rotor hat or under the caliper mounting ears.

2. Check for fit with a 914-6 caliper and 911 rear "and" put 4.5 to 5mm spacers under the rotor hat or under the caliper mounting ears. Some brands of 911 rear rotors (Brembo Sports) seem to fit in this application whereas Zimmermann and Sebro appear to need the diameter trimmed.

If you go to a vented rotor you have the choice of either special ordering the factory GT rear rotors (still available and around $250.00 each last we checked) or simply spacing out the 911 rear rotor 1/2 the distance of the 10mm caliper spacer.

In Phil and Chris's case, the group buy used 914 hubs and 914 rotors so everything is a straight forward bolt on application.

[DRPHIL914]

Eric,

thanks for all this info. for once it seams i made the right decision, that is to NOT change my calipers, but stay with the stock ones. I did not know as i was thinking about this last week ,and i was strongly considering: the Brembo alloy front caliper "upgrade" and 914-6 rears, that not only would it be so much more $$, it would not have been the best decision considering my choice of conversion-(914 rotors drilled to the 5 lug spec). Now if i had sourced 911 hubs etc, then of course 911 rotors and matching calipers would be the way to go. So- glad i asked the question before just blindly jumping in and going the other way.
-btw the rest of my order arrived yesterday!! Going to have fun this weekend -

except i think i just realized that although i just put my tranny back in and replaced all my CV gaskets, i guess i will have to replace these again?(its been less than 1500 miles)

Phil

Some Further Edification:

There's a couple ways to go to get a 5x130 rotor on the back of a 914 and, there are a lot of fit issues with each. The choice is usually predicated upon price and caliper selection.

If you are using stock 914-4 calipers with modified 914-4 hubs the choice should be a 914-4 rear rotor drilled to the 5x130 specs. with care given when indexing to retain the 2 chamfered mounting holes. The reasons being:

1. Your 914 hubs have these mounting holes machined into them and hopefully, they were also indexed to retain them. On our "group buy" the hubs and 914 rear rotors were both indexed to match and the mounting holes were retained.

2. You're going to have to machine either rotor so you might as well machine the less expensive 914-4 rotor to 5x130 vs. machining the expensive 914-6 rotor to the proper diameter

If you are using 911 rear hubs (as the 914-6 did) and stock 914-4 calipers, then you should probably get the 914-6 rotors and have them machine the diameter to match the 914-4 diameter. This involves shaving 2mm off the edge or 4mm off the total diameter. Because:

1. You will not have to machine two new rotor mounting screws into your 911/914-6 hubs.

2. You will not have to machine the rotor to 5x130. With both of those bits of machining needed, it would probably be a wash in price for the 914-4 rotor and the 914-6 rotor with minimal machining needed.

Obviously, 914-6 calipers and 914-6 rotors will mate right up. 914-6 rotors and 911 rear calipers will also mate up.

Here's another element of surprise:

If you want to move to a vented rear rotor (911 is about the only one available), then you will need to:

1. Take 4mm off the diameter if you are using a spaced 914-4 caliper "and" put 4.5 to 5mm spacers under the rotor hat or under the caliper mounting ears.

2. Check for fit with a 914-6 caliper and 911 rear "and" put 4.5 to 5mm spacers under the rotor hat or under the caliper mounting ears. Some brands of 911 rear rotors (Brembo Sports) seem to fit in this application whereas Zimmermann and Sebro appear to need the diameter trimmed.

If you go to a vented rotor you have the choice of either special ordering the factory GT rear rotors (still available and around $250.00 each last we checked) or simply spacing out the 911 rear rotor 1/2 the distance of the 10mm caliper spacer.

In Phil and Chris's case, the group buy used 914 hubs and 914 rotors so everything is a straight forward bolt on application.

[bigkensteele]

Some Further Edification:
...
If you are using stock 914-4 calipers with modified 914-4 hubs the choice should be a 914-4 rear rotor drilled to the 5x130 specs. with care given when indexing to retain the 2 chamfered mounting holes. The reasons being:

1. Your 914 hubs have these mounting holes machined into them and hopefully, they were also indexed to retain them. On our "group buy" the hubs and 914 rear rotors were both indexed to match and the mounting holes were retained.

2. You're going to have to machine either rotor so you might as well machine the less expensive 914-4 rotor to 5x130 vs. machining the expensive 914-6 rotor to the proper diameter.

Crap!

Anybody need a set of unused 914-6 rear rotors? Better yet, is anyone in the opposite predicament from me, needing 6 rotors instead of machined 4s?
Nevermind (IMG:style_emoticons/default/screwy.gif)

[Jeffs9146]

Just have the rotors milled 2mm! If you don't want them......I will take them! (IMG:style_emoticons/default/shades.gif)

[bigkensteele]

Just have the rotors milled 2mm! If you don't want them......I will take them! (IMG:style_emoticons/default/shades.gif)

I just realized that I misunderstood. I was thinking that Eric was saying that the chamfered holes for the mounting screws were not on the 6 rotors. I just went out to the garage to check, and they are there. So I am good.

[Jeffs9146]

Just have the rotors milled 2mm! If you don't want them......I will take them! (IMG:style_emoticons/default/shades.gif)

I just realized that I misunderstood. I was thinking that Eric was saying that the chamfered holes for the mounting screws were not on the 6 rotors. I just went out to the garage to check, and they are there. So I am good.

(IMG:style_emoticons/default/beerchug.gif)

FYI: The holes for the screw that holds the rotor on may not be in the proper place if you have 914-4 hubs that have been redrilled and studded! But that is not a big deal, just a pain sometimes! I have redrilled the screw hole before and made it work but it is not nessary!