Jeff's 3.8 and 4.2 Projects.

XR7 Dave

Registered User
Flex, that Morana set used long discontinued parts, so you can't copy that. The nice thing about that set was that the lower gear was already the correct size and it included the right chain. What Jeff is doing is the only way anymore.

Couple hints - you don't want to use a tensioner. The added abrasiveness of the roller chain vs. the stock flat link chain will chew it up and can cause catastrophic failure. It's happened.

Also, the SBF crank gear is narrower than the stock one. This will cause alignment issues if your vehicle is an 89-93 as those are very sensitive to crankshaft sensor alignment. Make a spacer so it's the correct thickness.

I'm sure you've looked at gear alignment. It's a bit tricky with SBF timing sets because there are many different iterations on the upper gear, many are designed for use with an oil pump eccentric, one piece, two piece, etc. It's annoying, but every single one is different.

Also, consider chain lubrication. The stock gear had forced oiling from the camshaft though chamfers and grooves in the machining. Getting oil to the roller chain will be a factor in long life while minimizing stretch.

Oh and on the girdle situation, consider using steel inserts since you can't use double nuts. You already machined the reliefs oversize, go ahead and put some stepped hard inserts in there so the aluminum distortion is minimized during torquing. With the ARP studs the torque values will be significantly higher than stock, so do everything you can to protect the aluminum.
 
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jb351

SCCoA Member
Flex, that Morana set used long discontinued parts, so you can't copy that. The nice thing about that set was that the lower gear was already the correct size and it included the right chain. What Jeff is doing is the only way anymore.

Couple hints - you don't want to use a tensioner. The added abrasiveness of the roller chain vs. the stock flat link chain will chew it up and can cause catastrophic failure. It's happened.

Also, the SBF crank gear is narrower than the stock one. This will cause alignment issues if your vehicle is an 89-93 as those are very sensitive to crankshaft sensor alignment. Make a spacer so it's the correct thickness.

I'm sure you've looked at gear alignment. It's a bit tricky with SBF timing sets because there are many different iterations on the upper gear, many are designed for use with an oil pump eccentric, one piece, two piece, etc. It's annoying, but every single one is different.

Also, consider chain lubrication. The stock gear had forced oiling from the camshaft though chamfers and grooves in the machining. Getting oil to the roller chain will be a factor in long life while minimizing stretch.

Oh and on the girdle situation, consider using steel inserts since you can't use double nuts. You already machined the reliefs oversize, go ahead and put some stepped hard inserts in there so the aluminum distortion is minimized during torquing. With the ARP studs the torque values will be significantly higher than stock, so do everything you can to protect the aluminum.

Thanks for the tips and advice David. It is very much appreciated.

I had been wondering about the tensioner since I trial fitted it, it really didn't seem to need it but I wasn't sure or not. Thanks for re-assuring my hunch, I will shelve it.

The gear alignment I wondered about when I first put it on but had not had a chance to get back to it to check it since checking the overall chain fitment. I just had another look at it now after seeing your post and sure enough it needs a spacer. I will make one next week for it.

It never occurred to me to use steel inserts in the girdle but it makes perfect sense and there is room and clearance to do so. I will make the modifications to it.
 

Flex

SCCoA Member
Good info David. Morana does say that you can run a tensioner with the double roller and Milodon had them available for some motors. I kept it on my brother's motor after reading that. Should I tear it apart and remove it? Who experienced the failures?

What chain do you use when you rebuild?

In regards to the oil pan Jeff, the 4.2 pan is a bit bigger than the car pan. Unfortunately they don't work in the super coupe. Does anyone know why the factory pan has that half round cast into the back of the pan? The 4.2 2 wheel drive pan does not have it.
 

jb351

SCCoA Member
In regards to the oil pan Jeff, the 4.2 pan is a bit bigger than the car pan. Unfortunately they don't work in the super coupe. Does anyone know why the factory pan has that half round cast into the back of the pan? The 4.2 2 wheel drive pan does not have it.
It is too bad it won't fit. Oil pan options are extremely limited it seems without going the custom route.

I suspect that the oil pan was also used for fwd cars with the 3.8 as well. It might have been clearance for the transaxel or something.
 

XR7 Dave

Registered User
When a tensioner fails, it will cause all sorts of havoc. I would not run one. I've seen one break the timing chain and of course bent half the valves. I've seen another where the chain didn't break but the parts found their way into the oil pan where a connecting rod shoved them through the pan. Not pretty.

The Mustang oil pan will fit and doesn't have the cutout in the rear. They can be bought new pretty cheap and then baffling can be welded into them. I've done this. You don't need more capacity, just better clearance around things and some baffling. I've cut out the front to add 1/2" clearance which is about all you have up against the stock K member and steering rack anyway. If you use a Mustang oil pan you should relocate the pickup more to the rear since the pan has a larger bottom footprint.
 

jb351

SCCoA Member
When a tensioner fails, it will cause all sorts of havoc. I would not run one. I've seen one break the timing chain and of course bent half the valves. I've seen another where the chain didn't break but the parts found their way into the oil pan where a connecting rod shoved them through the pan. Not pretty.

The Mustang oil pan will fit and doesn't have the cutout in the rear. They can be bought new pretty cheap and then baffling can be welded into them. I've done this. You don't need more capacity, just better clearance around things and some baffling. I've cut out the front to add 1/2" clearance which is about all you have up against the stock K member and steering rack anyway. If you use a Mustang oil pan you should relocate the pickup more to the rear since the pan has a larger bottom footprint.

Just checked Rock Auto and I can get a new oil pan for as little as $115 CAD + shipping. On the other hand I can probably buy some aluminum plate for less and invest some sweat equity and make a new pan or possibly save the flange of the old pan and weld a bunch of new metal to it instead. The smarter decision would be to buy the oil pan and make a couple of mods to it but it would be way more fun for me to design and fab a new pan. Might just shelve the oil pan issue for the moment and revisit it later.
 

jb351

SCCoA Member
I made up the stepped steel inserts for the stud girdle that David had suggested. I used a 1" piece of Grade 8 threaded rod and made the inserts out of that in the lathe then installed them in the girdle with a dab of loctite 242.



Then I made up the spacer for the crankshaft timing gear for proper gear alignment. I had an timing old gear from a previous carb'd 3.8 so I just put that in the lathe, turned it size then parted it off. It was easier that turning, boring and then broaching a new one and I like the idea of piece of my first real car (86 Cougar) making it's way into the new engine.

 

Flex

SCCoA Member
When a tensioner fails, it will cause all sorts of havoc. I would not run one. I've seen one break the timing chain and of course bent half the valves. I've seen another where the chain didn't break but the parts found their way into the oil pan where a connecting rod shoved them through the pan. Not pretty.

The Mustang oil pan will fit and doesn't have the cutout in the rear. They can be bought new pretty cheap and then baffling can be welded into them. I've done this. You don't need more capacity, just better clearance around things and some baffling. I've cut out the front to add 1/2" clearance which is about all you have up against the stock K member and steering rack anyway. If you use a Mustang oil pan you should relocate the pickup more to the rear since the pan has a larger bottom footprint.


Question on the Mustang pan David. I found one cheap. I am a fan of more oil. Have you drilled and tapped for the oil sensor?
 

jb351

SCCoA Member
I made the stepped steel inserts for the girdle a bit longer than I needed them to be so I had to cut them down a touch on the underside after they were installed with a drop of loctite 242 for retention as I move it around.



My bearing came in today so I machined the existing thrust spacer for it and added oil grooves front and rear like I had seen SCU do on theirs.




I think that about wraps up the double roller timing chain/roller thrust bearing part of the project.
 

Flex

SCCoA Member
When a tensioner fails, it will cause all sorts of havoc. I would not run one. I've seen one break the timing chain and of course bent half the valves. I've seen another where the chain didn't break but the parts found their way into the oil pan where a connecting rod shoved them through the pan. Not pretty.

The Mustang oil pan will fit and doesn't have the cutout in the rear. They can be bought new pretty cheap and then baffling can be welded into them. I've done this. You don't need more capacity, just better clearance around things and some baffling. I've cut out the front to add 1/2" clearance which is about all you have up against the stock K member and steering rack anyway. If you use a Mustang oil pan you should relocate the pickup more to the rear since the pan has a larger bottom footprint.

David,

How do you deal with the torque converter nuts or have you done this with just 5 spd cars?
 

Flex

SCCoA Member
Jeff,

Both yourself and David Neibert mentioned bushing the mains. I assume this is to eliminate cap walk, but is that needed with a girdle?
 

jb351

SCCoA Member
Jeff,

Both yourself and David Neibert mentioned bushing the mains. I assume this is to eliminate cap walk, but is that needed with a girdle?

I suspect that a girdle would help some but without bushing the caps there is still room for the caps to walk due to the size of the bolt holes in the caps/girdle compared to the size of the bolts or studs used. The holes in the SC block caps are 0.500" and the largest shoulder on the stock bolt and diameter of a replacement stud is 0.468". This allows potential movement of 0.032" or 1/32" which is quite a bit as it can move 0.01625" (1/64") toward the front and rear. With the bushings any movement is all but eliminated or limited to the clearance between the outer diameter of the bushing and the inner diameter of the main cap hole which should be next to nothing.

I made the girdle before I found out about bushing the caps. I seen main cap bushing on SCU's facebook page and thought it was a very good idea. Getting the proper fit and alignment is critical though and very time consuming and you will need the mains align-honed afterwards. The girdle I made just fits the studs diameter with minimal clearance and also locks side to side into the top machined step on my main caps. This is about as rigid as I can make the bottom end without going to a 4-bolt main conversion. I am confident in the bottom end now regardless but making some 4-bolt main caps for it would have been a fun project, maybe next time.
 
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jb351

SCCoA Member
Back to the intake manifold.....

I finally got around to adding the bolt holes that allows the middle intake section to bolt to the modified Freestar lower. It was tricky to get all the holes in the right places. What I did was locate, drill and tap the center 3 holes for alignment then marked where I wanted the holes to go on the lower intake and then drilled and tapped them. After that I took some setscrews and sharpened them to a point and threaded them pointy side out into the new lower holes. Then I placed the middle section on top of the points and lightly bolted it down with the 3 middle holes. After lightly tapping the middle intake with a rubber mallet I was left with punch marks on the bottom of the middle intake from the "pointy studs". I then drilled and countersunk the holes.

There some port matching to do between then two pieces but I had been expecting that since the beginning but at least now either the M90 or Turbo plenum will bolt to it properly.



It's going to need a bit of clearance on the bottom edge where the intake manifold bolt heads will be. No biggie though.
 

jb351

SCCoA Member
Looks nice bud.

Thanks Flex.

Today I machined and welded some brackets for the fuel rails on to the middle intake section. It holds them very securely and allows easy swapping between the M90 blower and turbo plenum tops. The fuel injectors are just el 'cheapo chinese ones I bought on ebay to use for mock ups and measuring. I don't have the actual fuel injectors yet. I figure #80 or #90 ones should work out for it with the power I am hoping to put down with it.

 

Flex

SCCoA Member
Well that will definitely be a unique build. The splitport centrifugal and turbo cars have made good power in the past and the M112 mock ups lacked an intercooler which greatly reduced their capabilities.

Why a Freestar intake? Why not a Mustang split port? The Mustang single port heads don't have the same thickness in the jackets as the SC so they can't be ported as much. I too started to work on a set of split ports for my brother's 2000 Mustang that is getting a 4.3 kit and am hesitant to cut too deep. I would love to see the pictures of the cutaway head if you decide to do it.
 

jb351

SCCoA Member
Well that will definitely be a unique build. The splitport centrifugal and turbo cars have made good power in the past and the M112 mock ups lacked an intercooler which greatly reduced their capabilities.

Why a Freestar intake? Why not a Mustang split port? The Mustang single port heads don't have the same thickness in the jackets as the SC so they can't be ported as much. I too started to work on a set of split ports for my brother's 2000 Mustang that is getting a 4.3 kit and am hesitant to cut too deep. I would love to see the pictures of the cutaway head if you decide to do it.

The Freestar lower is basically a huge open path to the cylinder head and has no EGR stuff to plug like some of the other intakes. Just remove the IMRC shaft and butterflies and then plug the IMRC holes and it's ready to go.



I milled an inch off of the top for the sake of hood clearance but in retrospec I wish I hadn't as it would not have been as much work and easier to replicate down the road if needed but at the time I was building for the M90 intake only but now with the turbo plenum I could have kept the lower intake the same size and just lowered the plenum a bit.

When I chop up the scrapped head I will post the pics here. I'll cut through the center of an intake and exhaust port. I will probably get to it tomorrow sometime.
 

jb351

SCCoA Member
I would love to see the pictures of the cutaway head if you decide to do it.

Done. I chopped it up this morning. Keep in mind that this head had some porting started on the intake side and about 0.100" milled off the deck as I was trying different speeds and feeds for a good surface finish before I milled the good heads.



Exhaust:



Intake:
 
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