[1968 GTO Resto-Mod]

i spent most of the day yesterday reading through this thread and i must say i am quite impressed with the effort that has gone into developing this idea.
currently i am building out the chassis of my 68 GTO but it certainly isn't too early to be thinking about what to do with the motor... and this serpentine idea has been on my mind for awhile.
you can see my build thread here:
http://www.gtoforum.com/f83/1968-gto...sto-mod-39843/

i am so excited to see that jimmo and ollie have proven this can be done in true DIY fashion!
are you guys still looking at this thread?

my project is a 1968 pontiac 400 (engine code XM).
there is a photo of the motor attached to this message.

i would be very grateful if i could get some input from you guys on my project as it seems like this serpentine idea is totally within the realm of possibility for me!

any help is appreciated!
thanks!

[Ollie]

Hi,1968 GTO Resto-mod.

Welcome to the Forums. Yes, I am subscribed to this thread, so any time a new entry is posted I get notified.
I see you have a 1968 engine with a 4 inch deep water pump. Keep in mind this modification was done on a later engine with a 4 1/2 inch ware pump.
You will have to figure out the correct spacer length for your engine.
I purchased the Idler arm, Power steering pump/ alternator Spacer, Water pump and Crank pulley from Jimmo.
The Alternator and Power Steering pump on E-bay.
The Sanden A/C compressor bracket form Vintage AIR.

[jimmo]

Welcome,Im still here too. I mostly lurk but I chime in once in a while. Id be happy to help in any way I can.

Ollie, your system is looking nice! when will ya be ready to fire it up?

By the way, for anyone interested, when winter hit I had a few people contact me looking for parts. I dont have much left, only spacers and the idler arm brackets. However, as soon as the snow melts away I plan on checking the junkyard for more pulleys.

[Tom Vaught]

So what bracket (year/application) was used for the Alternator and P/S on the driver's side?

[Ollie]

Hi, jimmo,
The motor is assembled.
Getting the MegaSquirt ready to go, so it can be run on the Dyno. wow what a lot of work building the wiring harness.

Originally Posted by Tom Vaught

So what bracket (year/application) was used for the Alternator and P/S on the driver's side?

I used a 79, alternator bracket. There is also an earlier bracket that will work. I can supply PN tomorrow.
With a E-bay 140 amp Alternator and Chevy/GMC power steering pump With the Hydro-boost brakes. The power steering pump is a press on pulley can be adjusted for alignment.

[Ollie]

As promised these are the two alternator brackets that will work with jimmo's serpentine belt system.
1. Photo of 79TA alternator bracket.
2. Photo of alternator bracket pn. 482254 pn stamped on back side.
Notice the differences in the off set jog. either bracket will work.

[1968 GTO Resto-Mod]

thanks for your response!
i plan to start mocking it up this week... might even look around at some of the local salvage yards to see if i can find the pulleys.
my GTO didn't come with the AC option so my application will look more like jimmo's setup as described in post #69.
thanks for the tip on the alternator bracket.
i'll start looking for one immediately.
attached to this reply are some photos of my power steering pump and it's mounting bracket.
the power steering pump has the "press-on" style shaft with keyway for the pulley...
will i be able to use the original pump?
also, will i have to mill the backside of the mounting bracket to accommodate a spacer like the one jimmo had fabricated to fit between his power steering bracket and the cylinder head?
i'm sure that i will have more questions as i proceed but if you guys could help me out with some guidance on these issues it would sure help me get off on the right foot.
please let me know if there is anything you would like to see a picture of, or if you need to know anything else about my original equipment.
thank you so much for your help!
danny

[Ollie]

Hold your horses on the alternator bracket. Your set up is going to be a whole different set up.
First thing I would do is obtain the water pump and crank pulley. In one of his post jimmo mentions which models he got the pulleys from. Mount those up and start taking a lot of measurements. the first measurement should be from the back of the water pump pulley. This will give you an idea of where the brackets should be.
The 68 crank pulley is 6 bolt so it may need to be re-drilled.
When taking any measurements, be sure to measure from a machined surface, not a cast surface.

[jimmo]

Yea, posts #69 thru 76 is where the bulk of the original info is but your system might need all together different pulleys. I am not familiar with the early stuff. Is it possible to get a newer style power steering pump to fit that motor?
Just curious, if you get a chance can you put the water pump in place and run a straight edge from the flange to the balancer to measure the offset? Im wondering what the offset is. Just a ballpark is good. Id like to see how it compares to the offset of mine to see how the spacing will differ.

[Ollie]

Yes the spacing is going to be different.
The early 8 bolt water pump is 1/2 inch shorter than the 11 bolt.
The balancer is 6 bolt rather than 4.
The alternator and power steering pump mount are the cast aluminum bracket, 1968 GTO Resto-mod posted above.
The early heads only have 4 bolt holes on the end not 5 like the late heads.
Of course the missing hole is the one up by the water cross over that is the alternator pivot.

PS
jimmo
Did you get the belt problem figured out.

[1968 GTO Resto-Mod]

wow guys thanks so much for your input!
i'm at the shop measuring now, but i can't post photos from my phone...
the offset from face of water pump pulley mounting flange to face of harmonic balancer is about 2.265" (measured without water pump gasket in place).
the water pump is about 3.656" deep from mounting surface to face of pulley mounting flange.
my harmonic balancer has 4 pulley mounting holes.
if i'm going to pull this midification off i'm going to have to find a way to use the original power steering pump because it's been rebuilt and upgraded to work with the 12:1 steering ratio upgrade i've had done to the steering gear.
thanks again for your help!
i really appreciate it!
danny

[1968 GTO Resto-Mod]

this is about as far as i got with it today.
i won't have my hands on the power steering pump for about another week.
thanks for your interest guys!
jimmo, please let me know how that offset compares to your setup.

[AROWHED]

I bought a new a PS pump for a 95 Chevy 1/2 ton pickup with a 350, it already has the serpentine pulley attached, and if not you can order it seperately. The serp pulley will not work on the older pumps. HOWEVER, you will need to swap the pump's pressure output fitting with the one from your old style pump, OR change the fitting on that end of your high pressure hose..because of different styles. Or just have a new hose made at NAPA, etc. Old is inverted flare, new is bubble flare.

One other thing, my PS brackets are from a 73 455, and bolting up the 95 pump was a snap...really just about any year Saginaw pump will be, because (I believe) the bolt hole bosses are all in the same locations. So, you *should* be able to use your 68 brackets, but I wouldn't, since Jimmo's PS pump spacer is specifically designed for the much easier to adjust 70's style brackets. Since a period correct look is obviously out the window with a serp belt, I suggest losing the 60's brackets.

[jimmo]

OK, I measured my offset in a very non-scientific way and got aprox. 2.85". Once your gasket is in place and the math is done its probably the 1/2 difference that Ollie mentioned earlier.
To get around that you just need to get a crank pulley with an offset that is 1/2" less than the one from the f150. That shouldnt be hard to find at all. There are tons of different sizes of crank pulleys in the junkyard unlike the serpentine water pump pulley where I only found 3 to choose from and one of those(the sable/taurus) is made of plastic.

If your heart is set on that power steering pump, I think march sells a pulley for that but I dont know how much adjustment it will yield for belt alignment.
The largest hurdle I see is mounting an idler pulley between the waterpump and alternator if you are not able to use the newer style alternator bracket.

Does anyone know if this older style power steering pump will mount up to a 70s style bracket system??

[Ollie]

Another problem he has is using early heads. They only have 4 bolt holes. Later heads have 5 bolt holes, of course the 5th bolt hole near the water cross over is the alternator pivot bolt.

[1968 GTO Resto-Mod]

hey guys, thanks so much for putting some of your energy into this idea.
it's clear at this point there will be much more to this than simply recreating jimmo's setup... i'll have to put a lot of thought into this.
i've already talked to a couple local salvage yards about pulleys.
ollie is right about the 4 threaded holes in the cylinder head...
also, i'm considering upgrading to a flowkooler hi-flow water pump, and a 12si alternator, so i will know more about what it's going to take to develop this serpentine conversion for my application after i get these issues resolved.
thanks again for your help!
danny

[huddie]

Would this work on an engine using an electric water pump?Just alternator and power steering pump.Thanks.

[jimmo]

It would probably be a much easier install without the waterpump. Is this an A.C. or non A.C. system?

[huddie]

Non AC.

[jimmo]

Im pretty sure the belt would need to be routed around the waterpump. Im just guessing the pump probably sticks out too far for the belt to pass in front of it.
If it were me, I would try it without any of the spacers. I would replace the alt and ps pulleys first the try to find a crank pulley that will land in line with those.
In my system I spaced the alternator and PS pump assembly 5/8" forward to line up with the waterpump but in your case the waterpump will not dictate the spacing of the other accessories. You would just need to find a crank pulley that is 5/8" more shallow than the f150 crank pulley I used.
The only only other obstacle is where to mount the idler pulley to direct the belt around the electric water pump.
If the water pump does not interfere with the belt you can just go from the crank straight to the alternator and ps pump with the belt.
All this talk revisited makes me wish I had a motor on a stand to mess around with.