Engine questions: 4.0L OHV and 5.0L V8

[TennTechMan]

I built up a 4.0L for my Ex Sport RWD 5-speed about a year and a half ago. Rebuilt to stock bottom end, 95TM heads, 422 cam, dual valve springs, headers, etc. I'm happy with the power/torque, fuel economy, and drivability.

Ever since getting the motor running, it's had some valve noise. I used stock length pushrods, and I'm not sure that was correct. I've seen a lot of people post what the correct length pushrods are with the 422 cam, but I have never found what length stock pushrods are to compare. Comp Cams told me stock length should be OK, but my valve noise makes me think otherwise.

About 12 months and 15,000 miles, the motor started burning oil. It's getting pretty bad now, so I'm going to have to do something about it. The bottom end of my engine had about 200k miles on it and didn't smoke when I pulled it out. All cylinders were within spec at the time of the build, so I didn't have it rebored, just re-honed. I'm not sure if the burning oil is coming around the rings or through the valve stem seals.

With the burning oil and valve noise, I'm planning to pull the motor back out in the spring. I just need to figure out what I'm going to put back into the Explorer. Re-build the 4.0 again? Buy a junkyard bottom end, and swap the 95TM heads, cam, etc onto the junkyard bottom end? Buy a wrecked 94 or 95 Mustang GT and swap the engine/trans from it into the Ex?

4.0L OHV build option:
I'm thinking of having the cylinders bored on the block that I have, and building it back with SOHC pistons and 95TM heads (11:1 + CR). Anyone know exactly what compression ratio this ends up with? If it's 11.5:1 or less, I can do that with a custom tune.

4.0L junkyard build:
End up with the same setup I have now, but with a newer and lower miles bottom end. I will make sure I get the Delta Cam rocker arms and pushrods when I put it together this time (same for the above option also). This is probably my cheapest option. Since it's the cheapest solution, it's the most likely.

94-95 Mustang GT swap:
I really want to still have a 5-speed, so this seems like the best option for me to get a 5.0L in the Ex. I'm not sure of many of the details on this, but I'll be sure to do some more research before I even seriously consider this option.

Sell it option:
Pretty self explanatory. Sell it, and start over. Least likely.


Any suggestions? I created a build thread when I built my original 4.0L if anyone wants any background. It's got pictures and video.

 

[91exploreron37]

If you wind up swapping in the 5.0 I'll buy the 4.0 heads from you.
Another member had a similar problem to yours when he installed his cam but much worse. He bought new pushrods and problem solved.
This is an email I have saved about the pushrods:

Are you going to re-use your stock rocker arms? Or are you going with the upgraded ones from Delta Cams? Reason I'm asking is this will affect the length of the pushrods you order.

Stock rocker arms: order 5.550" pushrods
Delta Cams Rocker arms: order 5.525" pushrods

In addition to that they're going to need the year. make, and type of motor you have. (i.e, ford 19xx 4.0l OHV v-6)

If you're wondering what the Delta Cams rocker arms are...basically there is a durability issue with the stock rocker arms. There is a cup where the pushrod sits and that cup as well as the pushrod gets worn. This causes a valve tapping like noise in older 4.0's that you might be familiar with. What the delta cams rocker arms have is a hardened steel cup pressed into them so that the pushrod doesn't wear on the rocker arm. The delta cam rocker arms are another good investment in the longevity of your motor but not a requirement....I think a set of them runs about $250

 

[TennTechMan]

Thanks for the reply. Those pushrod lengths are the same ones I've found on the forum before. What I haven't seen is the stock pushrod length. The only reason a different length pushrod would be needed is if the base circle for a stock cam is different than the Comp 422 cam. I'll do a little research and see if I can find the base circle diameter for the stock cam.



Another question for the 5.0L people. What is the weight difference between the 4.0L and the 5.0L? How about the weight difference between the stock 2WD 5-speed and the T-5 that would be in the 94-95 Mustang GT?


I'm still wondering about the 95TM heads and the SOHC pistons. What's the compression ratio come out to?

 

[robmurt04]

I'm still wondering about the 95TM heads and the SOHC pistons. What's the compression ratio come out to?

SOHC Pistons plus 95TM heads will put you in the 12:1 range.

 

[jd4242]

the stock length is 5.475 for 1st gen and with the 410 and the 422 you will need .050 longer witch is 5.525 and are available from smith brothers and cost $100.30 shipped (3 day to the east coast) and the part number is nr54a-ed, phone number is 18003671533 i also talked to delta cam (there web site is down) and they told me that you would not need to change the push rod length that there rockers are with in spec of your lifters and a set of rocker assembles cost $135 with a $42 core charge or if you want push rods with them its $182.50 + $42.00 core deposit. the part number is # F-40 and phone number is 800) 562-5500. this is all info for a 1st gen bottom end and top end if you use others heads you would have to double check

 

[little x]

Wow, that' twice the price I paid for my Smith Bro custom rods less then 4 years ago.

 

[jd4242]

they were $80, shipping is what killed me ,but thats the cheapest i could find them anywhere

 

[seth247]

All that slack in the pushrod was slamming the rocker down on the valve stem. Heavily whereing your stem seals/guides.

Take the heads to a machinist, have him press new ones in, good to go.

But if you've got a 5liter Layin around. Go for it!

 

[jd4242]

hey little x what size rods did you use?

 

[jd4242]

which dual valve springs did you use and what does it normally cost to have the head machined for them?

 

[CHEESYPOOFS]

Id have to say go 5.0 but then im a little biased... I love my 5.0 in my X. one thing if you do get a 5.0 out of a mustang get a set of GT-40P heads and the intake manifold from a 98-2001 explorer they are definately worth the effort.