serpentine conversion recommendation

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bricud

bricud

Cuda's Cuda
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I'm in the process of swapping the original 318 engine with a 1973 360. I wanted to convert the belt system to a serpentine system. Has power steering and no AC. I also wanted to upgrade the charging system in the process. Looking for a recommendation on a kit and what exactly is needed to accomplish this. I'll be replacing the power steering pump in the process also. I believe this means getting the reverse direction water pump but wanted to confirm exactly what I need. Thanks in advance.

Brian
 
In my opinion the easiest (and quite possible cheapest) would be the magnum setup. For that you’ll need a timing cover, accessory bracket, alternator (which you said you wanted to upgrade anyway so you can get a 90amp all the way to 150amp) crank pulley and you can either go with a truck style power steering pump and bracket or get a 5.2/5.9 Jeep pump and bracket. It mounts high on the driver side cylinder head. In all honesty you’d probably be just as well off going to a junkyard and buying a core for 2-300 then you get your accessory drive and a spare builder in the process.
 
Why convert to serpentine?
I'm pretty sure a Magnum timing cover won't take a mechanical fuel pump, fwiw.
 
The Magnum setup would also require the Dorman A/C delete pulley (unless you can locate one of the relatively rare non-A/C Magnum setups). The Magnum brackets also require a fair amount of trimming to clear a standard LA thermostat housing, unless you have a later manifold with the offset (and somewhat smaller) thermostat. Some of the mounting points will change also. Expect to do some rework to get the LA bypass hooked up to the Magnum water pump- usually just an angled barb adapter and a trimmed hose.
I don't know how it compares to the Jeep power steering pump and brackets, but the B van brackets fit well in the A body engine bay and clear the stock battery tray, which the truck bracket does not. Unsure of the Jeep or Dakota brackets.
 
I’m using a CVF 8 rib serpentine kit on my 360/410 SBM - no air but power steering. Fit, alignment and finish are all first class, thoroughly recommend their product! Used a Saginaw type PS pump and Std rotation as well so no need for RR water pump.

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I use the CVF setup as well, it is all iclusive. There is no room for a fan, so you will probably go electric.

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bricud said:
I'm in the process of swapping the original 318 engine with a 1973 360. I wanted to convert the belt system to a serpentine system. Has power steering and no AC. I also wanted to upgrade the charging system in the process. Looking for a recommendation on a kit and what exactly is needed to accomplish this. I'll be replacing the power steering pump in the process also. I believe this means getting the reverse direction water pump but wanted to confirm exactly what I need. Thanks in advance.

Brian
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Hey Brian. I used the MARCH serpentine set up w/P/S on my LA 360.
Turbosmblk said:
In my opinion the easiest (and quite possible cheapest) would be the magnum setup. For that you’ll need a timing cover, accessory bracket, alternator (which you said you wanted to upgrade anyway so you can get a 90amp all the way to 150amp) crank pulley and you can either go with a truck style power steering pump and bracket or get a 5.2/5.9 Jeep pump and bracket. It mounts high on the driver side cylinder head. In all honesty you’d probably be just as well off going to a junkyard and buying a core for 2-300 then you get your accessory drive and a spare builder in the process.
Click to expand...
Partially agree. For me, that would be a 100% done deal but IDK if the OP would want a spare engine to build taking up space.
However! Reselling what is left over could make it free. Purchase price dependent! (I like the idea.)
Phreakish said:
Why convert to serpentine?
I'm pretty sure a Magnum timing cover won't take a mechanical fuel pump, fwiw.
Click to expand...
Converting to a serpentine belt makes replacement easier. Not all store around me have the proper V belts. Why I don’t know since there still used on other machines.

The serpentine belt system is a personal choice. IMO, they look good.

That’s correct. The Magnum will not take a mechanical fuel pump.
Professor Fate said:
The Magnum setup would also require the Dorman A/C delete pulley (unless you can locate one of the relatively rare non-A/C Magnum setups).
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Not true. While I happen to have a Magnum non A/C bracket, I did initially have the regular Magnum bracket that had the A/C.
Professor Fate said:
The Magnum brackets also require a fair amount of trimming to clear a standard LA thermostat housing, unless you have a later manifold with the offset (and somewhat smaller) thermostat.
Click to expand...
I have not found that to be an issue at all. Though I have not used it with a OEM intake manifold, just a Edelbrock RPM- AG.

Professor Fate said:
Some of the mounting points will change also. Expect to do some rework to get the LA bypass hooked up to the Magnum water pump- usually just an angled barb adapter and a trimmed hose.
Click to expand...
I used extra hose length. Not pretty IMO.
Professor Fate said:
I don't know how it compares to the Jeep power steering pump and brackets, but the B van brackets fit well in the A body engine bay and clear the stock battery tray, which the truck bracket does not. Unsure of the Jeep or Dakota brackets.
Click to expand...
I’m grey in this area myself. I’m sure the answer is in the grey matter upstairs somewhere. I know it’s here on FABO…..
Somewhere!

LOL!
 
Pretty sure none of the Magnum PS setups will bolt to an LA, nor will the Magnum tensioner. The LA head is missing some of the bosses, and I know the block is missing the boss for the truck PS bracket. Not sure the missing boss on the block is that big of an issue, but the missing bosses on the head are more troublesome.

I was going to try and convert my '91 Dakota 318 to a Magnum serpentine setup as an intermediate step before doing the full 5.9 Magnum swap due to the '91 tensioner failing again, and that is what I remember running up against. In my case, the '91 only timing chain cover supports the PS pump so that wasn't a big issue, but the tensioner didn't work as I recall.

The '91 Dakota 318 timing chain cover would be one way to get around getting a PS mounted, but you would still need to build some kind of a mount for the tensioner.

There are certainly a couple of bosses that match up between the LA and Magnum heads, but as I recall there isn't anything there to make things stable as the LA head doesn't have the 3rd bolt to form the triangle.

Now, if a set of Magnum heads were swapped onto the LA like I've done on my Duster, it works great outside of the missing boss on the block. In that case, I would just use the Jeep bracket and pump as they just bolt to the head. But a full LA doesn't work in my opinion.
 
I'll be running the TrickFlow 190 power port heads so I have a few extra holes drilled for mounting brackets. I'm also running fuel injection so no mechanical fuel pump.
 
It's not just the mounting holes. The Magnum head bracket bosses are on a different plane than LA stuff. If I am not mistaken, I think the Magnum head bosses sit more forward than the LA. Unless the Trick Flows are Magnum heads, the Magnum stuff will not work on them.
 
bricud said:
I'll be running the TrickFlow 190 power port heads so I have a few extra holes drilled for mounting brackets. I'm also running fuel injection so no mechanical fuel pump.
Click to expand...

Looks like you are golden then. Those heads appear to match the Magnum bolt pattern on the end of the heads and are built up to match the plane.

Based on that, I would grab a Magnum TC cover, a van or Jeep PS bracket and a standard Alt/AC bracket.

Edit!!!

Just cut the AC mount section off and use the Alt mount. The big issue with the non-AC bracket is they move the idler so the truck and van PS doesn't cause the belt to rub, but the Jeep pumps are higher and don't have that issue. Both the van and truck pump that has the issue. And not sure if a Jeep pump clears the battery tray.

/Edit!!

Only other thing to be aware of is that the Magnum water pump has a threaded nose on it for the radiator fan. A Magnum fan might work, no idea, but I know they are different. Not a show stopper but something to be aware of. You could use a '91 Dakota 318 pump as they still used a bolt on fan, but you would have to find the matching pulley and the belt was narrower than the Magnum one so it might be too narrow. And no idea if the bolt pattern is the same, so an earlier fan might not bolt on either way.
 
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RustyRatRod said:
It's not just the mounting holes. The Magnum head bracket bosses are on a different plane than LA stuff. If I am not mistaken, I think the Magnum head bosses sit more forward than the LA. Unless the Trick Flows are Magnum heads, the Magnum stuff will not work on them.
Click to expand...

You are right, the LA has bosses up at the intake side of the head and then it tapers away from there. The Magnum head has bosses all the way across but the plane is the same as what the LA bosses use. So any head that is solid all the way across that face and has the holes drilled and tapped should work for either setup. The Trick Flow heads are solid and should work fine.

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DionR said:
You are right, the LA has bosses up at the intake side of the head and then it tapers away from there. The Magnum head has bosses all the way across but the plane is the same as what the LA bosses use. So any head that is solid all the way across that face and has the holes drilled and tapped should work for either setup. The Trick Flow heads are solid and should work fine.

View attachment 1716179961
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Well, thankfully Trick Flow had common sense. I knew I remembered some differences like that from when I built an LA 318 with Magnum heads.
 
Here is a thread about the non AC w/ PS issues and some fixes:

www.forabodiesonly.com

Van power steering bracket issues

Installed the power steering bracket on my magnum swap so I would gain battery tray clearance like others have done. However, when I route the belt like the factory van/truck diagram shows (for no a/c) it hits the water pump pulley. It's like the water pump pulley is too large. It is a factory...
www.forabodiesonly.com www.forabodiesonly.com
 
rumblefish360 said:
I have not found that to be an issue at all. Though I have not used it with a OEM intake manifold, just a Edelbrock RPM- AG
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No pics of my own, but pulled these from another thread:
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Magnum with LA air gap intake and serpentine
rumblefish360 said:
Not true. While I happen to have a Magnum non A/C bracket, I did initially have the regular Magnum bracket that had the A/C
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Sure it technically could still be used, but the belt wrap on the WP is pretty marginal without the ac or Dorman pulley.
 
So I've decided to go with the CVF serpentine belt kit. It has the brackets and pulleys I need and I am ordering it with the bracket for the 1 wire gm alternator set up to boost my output from the standard Chrysler 80 amp to 150 amp. Internal regulator also. I think the price wasn't too bad at $551 for what I need. I ordered their water pump as well to get the exit on the correct side. Thanks for all your input!
 
Just personal opinion, but not a fan of a multi belt system unless one of those belts turns a supercharger :D . And I don't think they fit the definition of a serpentine belt system because the accessories aren't all on one plane and (generally) there isn't a tensioner.

A multi belt setup is really just a v-belt system with multi groove belts which makes them even deeper and pushes some of the accessories that much farther off the front of the motor. Certainly the belt is better and it has the look, but I just don't think it is the same.

Not saying people shouldn't run them, they are probably tons better than a v-belt. I just disagree with labelling them a serpentine setup.
 
This is a Jeep bracket and pump, an a/c bracket that was cut to “appear” like a non a/c bracket. Belt routing is fine with this setup. The non ac idler is up and to the left about 3/4”

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DionR said:
Do you think the PS pump assembly would clear the stock battery tray?
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I honestly can’t say. This is in an e-body and I don’t own an A so I don’t know how much more cramped the engine bay is. I’ll say though the Jeep bracket is a lot tighter to the center of the engine than the la power steering that was previously installed.
 
DionR said:
Do you think the PS pump assembly would clear the stock battery tray?
Click to expand...
I just went and took some measurements. From the centerline of the water pump pulley to the outside of the reservoir is around 14.5”. I also “mocked” the original tray in place to show how much clearance there is. If the reservoir doesn’t clear a tray and battery there are ways around this. The later model pumps have remote reservoirs so you could use this pump and make a bracket to hold the reservoir if you’d like.

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