[ScottP]

I spent some time this winter working on a DIY serpentine conversion with a
bit of a twist. Much like the original DIY Serpentine work done by Jimmo
and others, mine started out with the usual Ford pulleys used for the crank
and water pump. As a reminder, they are:

Crank, Ford F2UA-6312-CA
Waterpump, Ford EOVE-8509-A7A

However, as part of this update, I wanted to install a CS144 alternator. I
had been running my EFI conversion on a 94A 12SI, but recently added dual
electric fans, and wanted a bit more idle output. This is an area where the
CS144 really shines over the older 10 and 12SI series alternators.

I also wanted to keep my original '70 power steering pump, which uses a keyed
0.625" shaft. This poses a problem in that I'm not aware of any OEM application
that would have this shaft type and use a 6-rib serpentine. Fortunately,
March makes an aluminum pulley that fits the bill nicely. Its available under
p/n 623-09 for $54. Once painted GM underhood black, it blends in nicely like
any other stock pulley.

With the pulleys worked out, I moved onto getting the spacing right. The water
pump pulley sits closest to the engine, with all others being spaced forward to
match it. In my case, the crank pulley needed two of the stock Pontiac crank
pulley washers (0.220" total) to come into alignment with the water pump. Now
that they were aligned, it was time to move to the alternator and PS pump.

The March PS pulley was a VERY close match to the CS144 on the stock '70 accessory
bracket. The CS144 only needed to be moved rearward by 0.150" to be perfectly
aligned with the March pulley. This was done by milling 0.150" off the rear of
the alternator case mounting boss and using a 0.150" spacer in the front (both
the CS144 and the 10/12SI are 2" thick in the lower mounting boss). For me, this
was far cleaner than moving the PS pump 0.150" forward. The entire alternator
and PS pump assembly was then moved forward by 1.350", bringing all 4 pulleys
into alignment.

My original '70 alternator bracket wasn't compatible with this swap, so I
picked up a '69 upper bracket set, which fit much more cleanly. It required
a 0.900" spacer between the upper alternator mount and the front of the new
bracket pair.

The system is manually tensioned at the moment, and is running smoothly. I still
have to get an idler and a tensioner installed, but figured folks might like to
see the progress so far.

-Scott

[rustedgoat]

Very nice

[vidguy]

Well done and good info!

[Schurkey]

First Guess: You're going to need a lot more "belt wrap" around the alternator and the PS pulleys. The water pump will be fine, and I can't tell about the crank pulley.

[HWYSTR455]

Originally Posted by Schurkey

First Guess: You're going to need a lot more "belt wrap" around the alternator and the PS pulleys. The water pump will be fine, and I can't tell about the crank pulley.

That's kind of what I was thinking, but it looks like there's plenty of room to put a pair of idlers in there. A simple plate with a stationary idler, and a sprung idler would do it.

Scott - What kind of intake feed are you using there, the one that attached to the TB? And are you using an air box? Post a pic, I'm very interested, I need ideas for my project.

EDIT - You could probably get away with one stationary or static idler, between the water pump and alt. The PS pulley looks like it has about enough wrap, but the alt looks like it's only like a 1/3 of the pulley making contact, or less. I don't see that much of a concern over the water pump, since it doesn't usually see that much 'load', so slip is less likely than it is with the alt.

.

[ScottP]

Originally Posted by HWYSTR455

That's kind of what I was thinking, but it looks like there's plenty of room to put a pair of idlers in there. A simple plate with a stationary idler, and a sprung idler would do it.

My primary goal when installing the idler and tensioner will be to continue to
improve belt wrap. The belt that's on there now is simply to let me start the
car and drive it around the garage. I'll post more pics when I get to that
phase of the project, but I can envision two idlers and one tensioner being
used in the final product.

Originally Posted by HWYSTR455

Scott - What kind of intake feed are you using there, the one that attached to the TB? And are you using an air box? Post a pic, I'm very interested, I need ideas for my project.

The intake plumbing is a mix of bits from various '99-07 GM trucks. The
section that's connected directly to the 90mm TB is from a '99-07 4.3L V6
1/2 ton Silverado/Sierra. Its GM p/n 25176891. I stumbled upon it at my
local used parts yard while looking for inspiration for how to cleanly plumb in
my 85mm 5-wire MAF sensor.

The filter is from an early C5 Vette cold air kit - can't remember the specific
manufacturer. I modified the core support to add openings for a cold air feed.
The intent is to eventually fabricate an enclosure around the air filter.
Interestingly enough, my datalogs show extremely low IATs, even idling in
traffic on a hot summer day, despite not having an enclosure yet.

-Scott

[HWYSTR455]

Wow, that's perfect. I've asked and mentioned on a number of threads that this is exactly what I was trying to piece together, and, there it is. Thank you VERY much for the elbow part number. And if you can determine the cold air kit part number or even manufacturer, that would be super.

Did you also cut into the inner fender well to help feed the filter/intake? Looks like you may have, and are pulling some air from below?

I'm guessing you're using a MegaSquirt then? I'd be interested in more info about your setup.

.

[ScottP]

Originally Posted by HWYSTR455

Wow, that's perfect. I've asked and mentioned on a number of threads that this is exactly what I was trying to piece together, and, there it is. Thank you VERY much for the elbow part number. And if you can determine the cold air kit part number or even manufacturer, that would be super.

I did some digging, and I think I've found a close match. It looks to be a
K&N RP-5070 filter. Mine is all rubber construction, but it looks like the new
variant is faux carbon fiber.

Originally Posted by HWYSTR455

Did you also cut into the inner fender well to help feed the filter/intake? Looks like you may have, and are pulling some air from below?

No cutting was done to the inner fender well - only a few small holes in the
core support that are hidden by the placement of the filter. The stock shape
of the '70 fullsize inner fenders provided lots of natural outside air. My plan
is to fabricate a simple two-sided barrier to better isolate the filter from the
engine bay. I need to start mocking things up in cardboard soon.

Originally Posted by HWYSTR455

I'm guessing you're using a MegaSquirt then? I'd be interested in more info about your setup.

No Megasquirt here, I exclusively use stock GM ECMs/PCMs for all of my
EFI projects. My 455 & 4L80E is controlled by a GM 12200411 PCM running
'02 L31 (Vortec 5700) & 4L80E code. That means that at the moment I'm
running a 4x crank trigger signal with a distributor, but I'm in the process of
sketching up the parts to convert to 24x and Coil Near Plug.

And, to tie this all back to the serpentine conversion, here's one last piece
of the puzzle. I just had a 0.220" crank spacer fabricated to move my
damper forward, and eliminate the spacer between the damper and the
serpentine crank pulley. This frees up just enough space between the
damper and the timing cover to locate my new crank sensor setup.

-Scott

[HWYSTR455]

So the filter comes with the tube and flange the filter mounts to?

I was thinking about using a K&N kit that has the box or baffle/divider as part of the kit. But shuffling thru part image by part image of 100s of kits is a pain.

On the crank trigger wheel, the user here 'ollie' has a 24x and 36x I believe wheel cad drawings that allow them to be directly attached to Pontiac balancers, can even mod a Holley one.

http://forums.maxperformanceinc.com/...&highlight=24x


.

[Interceptor]

Originally Posted by ScottP

Crank, Ford F2UA-6312-CA
Waterpump, Ford EOVE-8509-A7A

Looks good, thanks for sharing. Where can these 2 pulleys be found at a wrecker, what are they from?

[ScottP]

Originally Posted by Interceptor

Looks good, thanks for sharing. Where can these 2 pulleys be found at a wrecker, what are they from?

The answer to that and more can be found in the original DIY Serpentine thread:

http://forums.maxperformanceinc.com/...d.php?t=690512

[ScottP]

Originally Posted by HWYSTR455

So the filter comes with the tube and flange the filter mounts to?

No - the p/n I listed is just for a replacement filter that is the same size/shape as what I used, not an entire kit.

Originally Posted by HWYSTR455

I was thinking about using a K&N kit that has the box or baffle/divider as part of the kit. But shuffling thru part image by part image of 100s of kits is a pain.

I figured there was just about no hope that I'd find an enclosure that would
fit nicely in my fender well. I've resigned myself to the fact that I'll be
designing something custom, which I honestly don't mind.

Originally Posted by HWYSTR455

On the crank trigger wheel, the user here 'ollie' has a 24x and 36x I believe wheel cad drawings that allow them to be directly attached to Pontiac balancers, can even mod a Holley one.

http://forums.maxperformanceinc.com/...&highlight=24x

I like what he's done there, but I have a different design direction in mind.
One of my design requirements is that I use only OEM sensors for my EFI
conversions. The sensor I'm using for the crank position signal will be
mounted behind the balancer, similar to what you see on the Series2 3800's,
lots of GMs early 2000's V6's, and loads of Mitsubishi and Ford engines.
I'm also running a PowerBond balancer, which provides me with some nice
machined surfaces to reference for my trigger wheel and adapter.

-Scott

[HWYSTR455]

So the only tubes you used to go from the filter to the TB is the one you listed for the truck? The GM p/n 25176891 one?

.

[ScottP]

Originally Posted by HWYSTR455

So the only tubes you used to go from the filter to the TB is the one you listed for the truck? The GM p/n 25176891 one?

That's correct - I used two of them total. Keep in mind, in each case I only
used the section that I needed. So the piece I used from the TB to the MAF
sensor is one section I cut from the V6 tube. Same can be said for the
section from the MAF sensor to the filter - its also a section I cut from
another sample of that same p/n. Once you see one in person, it'll be a bit
more obvious - its a quite long section of tube and flex assemblies molded
into one part. With all of its bends, it can be cut up quite creatively to solve
lots of intake plumbing problems.

-Scott

[HWYSTR455]

Originally Posted by ScottP

That's correct - I used two of them total. Keep in mind, in each case I only
used the section that I needed. So the piece I used from the TB to the MAF
sensor is one section I cut from the V6 tube. Same can be said for the
section from the MAF sensor to the filter - its also a section I cut from
another sample of that same p/n. Once you see one in person, it'll be a bit
more obvious - its a quite long section of tube and flex assemblies molded
into one part. With all of its bends, it can be cut up quite creatively to solve
lots of intake plumbing problems.

-Scott

Ah, that's where I was confused, got it now, and thanks a ton! It wasn't obvious by the box or online pics, adding to the confusion. I will order one and play with it.

Sorry for the hijack!

.

[ScottP]

I know this is an old thread, but its my old thread so I think that makes it OK<g>

After almost 6 years of running the serpentine setup just as you see in the first
few posts, I finally got around to adding a pair of idlers to improve the routing
and the overall belt wrap. For reference, in all that time and driving, I never
experienced any belt slip, but I did want to finally bring this old project to a close.

I used a piece of 1/4"thick steel, 4"x8" and transferred the hole pattern from the
stock "hockey stick" (see the pics) onto the new plate. Some CAD (Cardboard
Aided Design, an expression one of my friends used when he saw this) was
used in the mockup process. Once I had the plate, the location for the two
new idlers was determined transferred from the cardboard and the plate
was drilled/tapped.

The new belt routing results in much better wrap, and an overall more
compact presentation. I elected to keep it manually tensioned using the
alternator, as that has worked really well this entire time. Looking forward
to getting some miles on this once spring rolls around.

-Scott

[gtospieg]

Nice job...

[71 Goatman]

The serpentine set-up looks great. I may take you idea and adapt to my engine, I have A/C so another pulley and longer belt will be in order.

[nUcLeArEnVoY]

Would that waterpump pulley you have on there work with a March Performance system seamlessly? I love the stock look and finish on it. Like it belongs there. I plan to do a serpentine conversion down the road using the budget March sport-trac system and am trying to avoid having it look too bling-bling, and have been hunting for 6-rib pulleys that have a stock-ish look to them. The crank pulley, alt pulley, PS pulleys that come with the kit look pretty basic if you omit the decorative covers, but I'm not too happy about the water pump pulley.

Thanks! Awesome setup, man.

[ScottP]

I doubt that the Ford water pump pulley would work with the March setup as-is,
simply because of the placement/spacing front to back. Its unlikely that the
Ford pulley is in the same plane. Its possible that you may be able to space
it out, if it just so happens that the Ford pulley is too far rearward, but I don't see
a good solution in the case where it happens to be too far forward.

That all being said, it certainly can't hurt to grab a used one and try it out.