4 lug vs. 5 lug

[dgraves]

My new 914 has a couple of badly converted 5 lug hubs. Now I have the conundrum of buying four 4-lug hubs and wheels or replacing the bad 5-lug hubs.

A couple of thoughts go through my mind, has anyone had problems with 5-lug conversions if done properly? Wheel failures? Stress on the suspension or brakes?

Replacing the bad hubs is probably the cheaper way of going. I have 5 very nice "cookie cutter" wheels, while not 914, they are in good shape and look fine on the car. I have a feeling selling these will not net enough to buy five 4-lug wheels.

I'd love some feedback. I'm not in this for show quality, but rather from a daily driver perspective. The balance of the car is in sweet condition.

Thanks, Dan

[Dave at Pelican Parts]

Front or rear? I am assuming the rear, since the four-lug front hubs are part of the brake rotor. (Likely a 911 front end on the car?)

The biggest thing to worry about with a badly-done five-lug rear conversion is parts failure. Holes that are too close to the edge, in metal that is too thin, or are too close to other holes, can cause problems. Which can be more easily provoked by driving the car hard, with lots of power or by large cornering forces or any impact (with potholes, curbs, etc.).

If the new lug holes are not centered around the center of the hub, the rear wheels will never balance correctly and there will always be some vibration. It's usually not unbearable, but it can get annoying after a while.

Wheel failures are unlikely unless the bolt pattern is messed up. (E.g., the 5 holes are not evenly spaced or some are 127mm from the center instead of 130mm.)

Cookies are great wheels for a 914. They look nice on most 914s, they're not expensive, and most of them fit our cars pretty well.

If you're worried about the hubs, replace them. It's not worth it to be worried the whole time you drive your car. (BTDT--other worries, but still!) I believe that Eric at PMB Performance carries correctly-modified hubs. I wouldn't be surprised if other places did as well. I don't think that we do, but it is worth pinging Bruce Stone or Glenn Sager in our Sales department to make sure. They're both 914 guys and pretty cool people to boot.

--DD

[dgraves]

Dave, you are amazing to take the time to answer in such detail. Thank you very much. I'll start looking for some 5-lug replacements.

Originally Posted by Dave at Pelican Parts

Front or rear? I am assuming the rear, since the four-lug front hubs are part of the brake rotor. (Likely a 911 front end on the car?)

The biggest thing to worry about with a badly-done five-lug rear conversion is parts failure. Holes that are too close to the edge, in metal that is too thin, or are too close to other holes, can cause problems. Which can be more easily provoked by driving the car hard, with lots of power or by large cornering forces or any impact (with potholes, curbs, etc.).

If the new lug holes are not centered around the center of the hub, the rear wheels will never balance correctly and there will always be some vibration. It's usually not unbearable, but it can get annoying after a while.

Wheel failures are unlikely unless the bolt pattern is messed up. (E.g., the 5 holes are not evenly spaced or some are 127mm from the center instead of 130mm.)

Cookies are great wheels for a 914. They look nice on most 914s, they're not expensive, and most of them fit our cars pretty well.

If you're worried about the hubs, replace them. It's not worth it to be worried the whole time you drive your car. (BTDT--other worries, but still!) I believe that Eric at PMB Performance carries correctly-modified hubs. I wouldn't be surprised if other places did as well. I don't think that we do, but it is worth pinging Bruce Stone or Glenn Sager in our Sales department to make sure. They're both 914 guys and pretty cool people to boot.

--DD

[dgraves]

Excuse the stupidity of this question, Dave. I have 5-lugs on both front and rear. Are you telling me that the front end would have to be changed out to a 911 front end in order to use 5-lug hubs?

Originally Posted by Dave at Pelican Parts

Front or rear? I am assuming the rear, since the four-lug front hubs are part of the brake rotor. (Likely a 911 front end on the car?)

The biggest thing to worry about with a badly-done five-lug rear conversion is parts failure. Holes that are too close to the edge, in metal that is too thin, or are too close to other holes, can cause problems. Which can be more easily provoked by driving the car hard, with lots of power or by large cornering forces or any impact (with potholes, curbs, etc.).

If the new lug holes are not centered around the center of the hub, the rear wheels will never balance correctly and there will always be some vibration. It's usually not unbearable, but it can get annoying after a while.

Wheel failures are unlikely unless the bolt pattern is messed up. (E.g., the 5 holes are not evenly spaced or some are 127mm from the center instead of 130mm.)

Cookies are great wheels for a 914. They look nice on most 914s, they're not expensive, and most of them fit our cars pretty well.

If you're worried about the hubs, replace them. It's not worth it to be worried the whole time you drive your car. (BTDT--other worries, but still!) I believe that Eric at PMB Performance carries correctly-modified hubs. I wouldn't be surprised if other places did as well. I don't think that we do, but it is worth pinging Bruce Stone or Glenn Sager in our Sales department to make sure. They're both 914 guys and pretty cool people to boot.

--DD

[racer]

Over the years you could convert to 5-lug by

1) Swapping out a full 911 front suspension (which is what the factory did for the 914-6)

2) Over the years, various folks have made adaptors and brake kits that allowed the use of 5-bolt wheels.


You don't mention if your current issue is with the front or the rear.

Maybe this will help? http://www.914world.com/bbs2/index.php?showtopic=105728

[dgraves]

Thanks, Racer, for the return note. I do have 5-bolt wheels on both the front and rear. I'm no expert by any means, so are you telling me that the car had to have a conversion to a 911 suspension in the front and rear to utilize these 5-bolt wheels?

Second follow up, would the use of 5-bolt wheels require a change in the OEM brakes?

Thank you,
Dan

Originally Posted by racer

Over the years you could convert to 5-lug by

1) Swapping out a full 911 front suspension (which is what the factory did for the 914-6)

2) Over the years, various folks have made adaptors and brake kits that allowed the use of 5-bolt wheels.


You don't mention if your current issue is with the front or the rear.

Maybe this will help? 914World.com - The fastest growing online 914 community!

[Emo993]

Dan, can you take a picture of you front and rear set-up (hubs and brakes). Would like to know how badly the conversion is and the problems your having. Mark

[Dave at Pelican Parts]

Here's a Tech Article on the various ways to convert from four-lug to five-lug:

Pelican Technical Article: 914 Five Bolt Pattern Conversion Guide

The short version is that there are three main ways to do the front:
- Re-drill the hubs with the five-lug pattern. You have to re-do this every time you replace the front rotors, since the rotor is part of the front hub.
- Use bolt-on four-to-five adapters. I personally dislike this approach, as I do not feel the common adapters are good enough to be safe on a 914 that is driven the way it was meant to be driven.
- Change over to a 911 front suspension.

The 911 struts bolt onto the 914 A-arms. You get big brakes and five-lug hubs at the same time, which is nice. You can use the 911 A-arms if you like, but you will have to use the torsion bars (and the eccentric at the back of the torsion bar) from the 911 as well because they have a different number of splines.

The rears are a bit more complex to do; you basically have to re-drill the four-lug hubs. Best to have studs pressed in, because the studs can actually provide more support than a threaded hole through the thin material of the hub. (There are specific combinations of parts from various year 911s and 944s that actually let you use hubs that are already five-lug, but those parts are relatively rare. And the 914-6 hubs are even moreso.)

--DD

[dgraves]

Mark, I don't have photos...not in a position to get under car or take off wheel. But, there is no modification to suspension or change to 911 or 914-6.

The 4-bolts were just badly modified.

Originally Posted by Emo993

Dan, can you take a picture of you front and rear set-up (hubs and brakes). Would like to know how badly the conversion is and the problems your having. Mark

[dgraves]

I don't have the wheels off currently, Mark. From what my mechanic tells me it was a bad job all the way around. Evidently spacers are used between the hub and wheel to get them to seat properly. No other suspension adaption was made to 914-6 or 911.
It looks like I've got to decide on either a correct set of 5 bolt modification hubs or change back to stock 4 bolt. It's too bad, I like the 5 bolt cookie cutter wheels that came on the car.

Originally Posted by Emo993

Dan, can you take a picture of you front and rear set-up (hubs and brakes). Would like to know how badly the conversion is and the problems your having. Mark

[Emo993]

Just FYI, I bought 911 fronts (struts, calipers/rotor and hubs, raised) from Rich Johnson and rear drilled hubs and rotors from Eric Shea....Both just great to deal with. Best, Mark

[dgraves]

Thanks, Mark. Eric at PMP set me right up with what I needed.
Best regards,
Dan

Originally Posted by Emo993

Just FYI, I bought 911 fronts (struts, calipers/rotor and hubs, raised) from Rich Johnson and rear drilled hubs and rotors from Eric Shea....Both just great to deal with. Best, Mark

[dgraves]

You are the go to guy, Dave. Sorry to bother you.

The attached photo is poor but maybe you can help me out. Is this a 914 or 911 tach. My car is a 1974-914. It has a 5 gauge (3 big, 2 small) dash instrument cluster. Looking at the tach directly under 3000 RPM marker between the 3 and the two triangles there is a small black circle. I've been told that this is the turn signal indicator. Is this correct? If so, why would my turn indicator be lighting a red circular light on my temp gauge and oil pressure gauge? Is my tach not stock to a 914? I also noted another back circle to the right of the 4 on my tach near a light emblem. Should this be a high beam indicator?

Thanks in advance.
Dan

[Dave at Pelican Parts]

It looks like a 914 tach. Since the tach guts count ignition pulses, a 6-cylinder tach will read wrong on a 4-cylinder motor, and vice-versa.

As you have been told, the light next to the two triangles is the single turn signal indicator. It should blink when either the left or right turn signals are blinking. And the light next to the shining light symbol is the high-beam indicator.

The similar lamp on the speedometer is for the running lights--it should be on when the headlight switch is pulled partway out, turning on the running lights but not the headlights.

--DD

[Mark Henry]

Without pics of the front and rear hubs it will be hard for us to tell you what you have but I'm assuming that you have adaptors, your 4 lug has been redrilled for 5 lug or you have a T front hubs and struts and redrilled rears.

For adaptors just take them off and get 4 bolt wheels.
For redrilled F/R hubs replace the front rotors, rear hubs and get 4 bolt wheels.
If it's just a bad rear job I'd get better redrilled hubs and stick with 5 bolt.

But honestly you could have funky brakes, early 911 non-vented rotors, heck it could be drilled for chevy rims, without pics we have no way of advising you on which way to go with this.

[Jim Smolka]

For the rear conversion, a couple of options...

Currently, my 914 rear 5 bolt, uses early 911 cv axles. Then I purchase 911 stub axles and brakes rotor etc. Found a set of 911 / 901 transmission stub axles and put them into the 914/901 gearbox. Then I installed a ~1" spacer between the 911/901 transmission.

A hard way to do this w/o the 911/901 gear box stub axles is

Used the regular 914 cv axles. Then I purchase 911 stub axles and brakes rotor etc. Then I installed an adapter that I make that allows the 911 stub axle to bolt up to the 914 cv joint. The adapter was custom made by a friend. Up to a point, this works well, but for 200+ HP, the 914 cv's are not the best

[Racerbvd]

88 Carrera 911 front struts, with 944 Turbo (modified to fit) calipers




The rear 4 lug hubs have been redrilled to 5 lug on these.


There is one more option (other than adapters)
A set of rear control arms that are modified to use SC and Carrera rear brakes, not an inexpensive choice, this set is also boxed and even more reinforced.



The Carrera struts with the 951 calipers and cookie cutter mounted.

[socal1200r]

I found a nice set of 924 phone dial wheels, 15x6, +52mm offset. Haven't pulled the trigger on them yet because I want to know what it would take to convert the stock 4-lug to 5-lug to mount these wheels, and if these wheels will work. From reading this thread and the technical article, seems that the easiest and least expensive way is to just get the stock rotors/hubs drilled to take 5x130 studs (14x1.5mm?). Understood whenever new rotors are needed they'll have to be drilled again with new studs, but at the rate I'd drive this car, that could take 10 years! Are 14x1.5mm wheel studs fairly common, or in the realm of unobtainium like other things for 914s?

[Racerbvd]

Originally Posted by socal1200r

I found a nice set of 924 phone dial wheels, 15x6, +52mm offset. Haven't pulled the trigger on them yet because I want to know what it would take to convert the stock 4-lug to 5-lug to mount these wheels, and if these wheels will work. From reading this thread and the technical article, seems that the easiest and least expensive way is to just get the stock rotors/hubs drilled to take 5x130 studs (14x1.5mm?). Understood whenever new rotors are needed they'll have to be drilled again with new studs, but at the rate I'd drive this car, that could take 10 years! Are 14x1.5mm wheel studs fairly common, or in the realm of unobtainium like other things for 914s?

The studs are common, but you would need spacers for the 924S rims, as you don't want over 23mm offset.
Early 911 and 9

[dgraves]

I purchased the 5-lug conversion package from PMB Performance. $772.40 includes everything you'll need including bearings and seals. It was a beautiful job. I had the hubs installed last week. Car rides "round" and smooth with 5 lug wheels.

Originally Posted by socal1200r

I found a nice set of 924 phone dial wheels, 15x6, +52mm offset. Haven't pulled the trigger on them yet because I want to know what it would take to convert the stock 4-lug to 5-lug to mount these wheels, and if these wheels will work. From reading this thread and the technical article, seems that the easiest and least expensive way is to just get the stock rotors/hubs drilled to take 5x130 studs (14x1.5mm?). Understood whenever new rotors are needed they'll have to be drilled again with new studs, but at the rate I'd drive this car, that could take 10 years! Are 14x1.5mm wheel studs fairly common, or in the realm of unobtainium like other things for 914s?