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4.0 OHV Performance Build - An extremely capable daily!

Hello,

Let me preface this post by saying that this is my first ever post in a forum, so if I'm doing something wrong, let me know. This thread is a follow-along of the build for my 1994 Explorer XLT 4.0 OHV. I just figured that other 1st gen enthusiast, like myself, would enjoy seeing my unique approach to building my 4.0 to be an extremely capable daily driver.

As for the truck, I purchased it in Seattle, WA for $1000 with 150k miles on it. At 200k I managed to blow the head gasket while playing in the TN ice storms... That's an excuse to upgrade! (or just rebuild, as far as my wife is concerned :D ) I bought a second engine from a buddy, and away I go!

(First post, so I'm testing this out with a picture)

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"No officer, I didn't see anyone doing donuts in the addition..."



OK! On to the story! First thing after the tare-down is to get what I need. And what I cant get I must make! I ordered a .020 over rebuild kit from EngineTech. Good price, but later, I found, some of the items in the kit needed to be replaced with higher quality ones.

In tearing down the old engine, I found some interesting things that I wasn't aware of. It appears that the push rods are solid and the rockers tips are very poorly lubed from whatever happens to splash on them. This engine having 280,000 miles on it, the rockers were near non-existent and the push rods looked like spears. Because I'm looking for every excuse to upgrade, I went with a set of Harland Sharp roller rockers with the Morana racing adjustable rocker setup.

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These rockers come with a 1.8:1 ratio as opposed to the 1.5:1 of the factory rockers. This is all fine and dandy, but I had already decided to order the 422 cam from Comp Cams and with the profile of that cam, I would end up with .601" lift at the valve. Performance-wise, no problem.... Parts-wise, PROBLEM. I called comp cams and they were unable to provide me with anything that would work, along with Pac Springs, so I did some research and found that behive springs for a for modular engine could work as long as I modified the heads and valve retainers.

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Once I got the springs in, I took some measurements and determined that in order to minimize the machine work, the springs would be best installed 'upside-down' from the traditional installation. I reground all of the valves and put a nice 3 angle valve-job in the head and measured my valve spring height. I determined that by machining the heads approximately .0150" lower in the spring pocket while keeping the same diameter for the guide OD I would have enough spring pressure and travel.

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Next, I took the spring retainers and cut the OD of the spring seat smaller to fit the other side of the beehive spring. I used an endmill with a .0100" radius to help reduce the chance of stress fractures.

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Next, I test assembled the heads to check spring heights and travel. Everything fit perfectly, but in order to compensate for the height of the valve stem seals, I will need to cut the valve guides down a little.
 



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I cant believe this didnt get more attention! Roller rockers in a 4.0!
 






Id love to see updates..

Couple of things..
1-how do you plan to mount those "post" roller rockers??
You get Toms whole kit??if so i thought it came with the rockers??

2-those springs pictured are not "behive" those look like comp cams 988 dual springs..if they are the 988s then nothing needed to be done with stock retainers..

3-how do you plan on oiling the rockers??you get Tom's spray bar kit?or lifters and pushrods
 






The rockers are an entire kit with a mounting pedestal and locking set screws and the roller rockers are lubricated through the provided lifters and hollow pushrods. I decided on this setup because the original engine that I disassembled (like many 4.0 OHVs) had a lot of ware on the factory pushrods and rockers.

As for the springs; yes there are not a traditional 'beehive' shape, but they are actually tapered to reduce the coil bind and provide more travel, so they are sold as beehive springs. They are P/N 26125... As far as I know they are specd for a Ford Modular engine. But that was just my best guess, and I could be wrong about the application.

If people are interested, I will start keeping this thread updated. I totally stopped due to an apparent lack of interest.
 






Im very interested in the roller rockers..ive been talking to Tom for years about them,i have yet found anyone to drop that kind of cash..fyi comp cams 988 dual springs wouldve worked.

If looking for real performance call Manley and get a set of custom 1.8 and 1.5 valves for it.they will run you $480ish but biggest performance gain you can get.those valves are extremely small..your need new hardened exhaust valve seats and custom bronze guides. .

SI makes stock stainless one piece valves in stock sizes..i wouldnt run the stock two piece valves,they have been know to break in half with the added spring pressure. Any SS valve will need custom bronze guides tho,the stock cast guides will wear and stick to the SS valve...TRUST ME

Also throw a Mellings M328hv oil pump in,helps a ton to get oil up top
 






Ps...can we get a mod to move this thread to the performance section??? [MENTION=71]Rick[/MENTION]
 






Im very interested in the roller rockers..ive been talking to Tom for years about them,i have yet found anyone to drop that kind of cash..fyi comp cams 988 dual springs wouldve worked.

If looking for real performance call Manley and get a set of custom 1.8 and 1.5 valves for it.they will run you $480ish but biggest performance gain you can get.those valves are extremely small..your need new hardened exhaust valve seats and custom bronze guides. .

SI makes stock stainless one piece valves in stock sizes..i wouldnt run the stock two piece valves,they have been know to break in half with the added spring pressure. Any SS valve will need custom bronze guides tho,the stock cast guides will wear and stick to the SS valve...TRUST ME

Also throw a Mellings M328hv oil pump in,helps a ton to get oil up top

I'm still a bit confused about how the 988 springs would have worked.... The installed height of the springs from the factory was only about 1.580"-1.590" I modified the cylinder heads to have an even 1.600". But with the rocker ratio and cam, the lift is .601". That's cutting it pretty close. I could have cut more off of the head, but they are OE heads, and since they are prone to crack in the spring seats I didn't want to cut any more than I absolutely had to. Especially with the Increased spring rate that was suggested for the cam. The springs I chose have a coil bind of .970", so there is a little bit of room left for 'oh sh**' moments.

Also, I do have the high volume oil pump. I made sure to get that, since the OHV is known for oiling issues.
 






The 988s is what is used for the 410 and 422 cam..the seats have to be milled for those to work also but nothing to the retainer. .if i recall i think Tom said that just 70 thousand needs to come off the valve stem seal guide for the rollers to work..you need to trim them about 30 thousand for the 422 to work anyways(100 total if 422 and rollers are used) ..also if i recall the lower manifold and lower manifold gaskets need to be cleared for the pushrods also

also the cast humps can all be removed from the exhaust ports (studs and bolts need to be installed)and the lower intake can use alot of material removed..

There aint much i havent done performance wise with the OHV

This happens if 30 thousand isn't removed and a 422 is ran with proper pushrods...this also is 988 springs..
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Bolts and studs after cast humps removed
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Here is the part # for the SI valves,highly recommended. Also use the felpro superduty head gaskets,they are blue and have a ""SD"" at the end of part number

SI valves part number,you have to call them
sev2027 and sev2028 $138 http://www.sivalves.com/onlinecatalog.html



Here is my thread..its long and lots of bs but TONS of info,tricks and part numbers in it..my new motor should be done hopefully next week

http://www.explorerforum.com/forums/showthread.php?t=382711&page=9

I have already purchased the heavy duty gaskets and ARP head studs. I have also already ported the heads and of course removed the bolt boss' inside the ports. I will take a look at those valves and see what I can do. I tried to find oversized valves initially and finding the valves wasn't the issue, so much as a keeper to match because they also had an oversized valve stem.
Thanks for the info!
 






Here is the Block after it was torn down;
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And on to the 'Boring' Work!
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I'm still a bit confused about how the 988 springs would have worked.... The installed height of the springs from the factory was only about 1.580"-1.590" I modified the cylinder heads to have an even 1.600". But with the rocker ratio and cam, the lift is .601". That's cutting it pretty close. I could have cut more off of the head, but they are OE heads, and since they are prone to crack in the spring seats I didn't want to cut any more than I absolutely had to. Especially with the Increased spring rate that was suggested for the cam. The springs I chose have a coil bind of .970", so there is a little bit of room left for 'oh sh**' moments.

Also, I do have the high volume oil pump. I made sure to get that, since the OHV is known for oiling issues.

Ok so ive done ALOT of research onto this as im debating getting these rollers ...

We are both wrong about a couple things..

Did you add in .060 into your coil bind and seat height equation? ?the 422 cam has .334 lobe height on intake..
.334x1.8=601
If your cam has a bind measurement of .970 then you only giving the middle coill .029 of clearance. .they will be smacking each other all the time and 90% will be binded at .601 lift..they call for .060 clearance in middle coil at full lift before coil bind..
.970-1.600-.060=0.570 <<max lift...
Max ratio rocker you can run with those springs is 1.7

Ive confirmed this with comp cams,how i figured out my 988 springs wont support .601 lift..
988s have a coil bind of 1.0 and installed spring height of 1.6 also..
1.0-1.6-.06=0.540 <<< max lift
Max ratio rockers i can run is 1.6


Here'sa diagram they sent me confirming where to measure for safe max lift before coil bind...also confirmed the "coil bind" measurement does not include the safety margin, its just when bind/damage happens

ValveSpringClearance_zps3ydr5ly9.gif
 






In my experience, in an engine that isn't running forced induction and isn't going to be running max RPMs for long periods of time, .030" should be sufficient. But I did factor in the extra clearance. Although, I do find it hard to believe that they haven't included any safety margin in the .060" clearance, if this is true, then I may end up with some problems. Of course, I can always just machine a little more out of the head. The only problem being that I am on the low end of seat pressure, so going any lower than 130 may be pushing it. The only advantage that I have is that I'm still running factory sized valves.
 






In my experience, in an engine that isn't running forced induction and isn't going to be running max RPMs for long periods of time, .030" should be sufficient. But I did factor in the extra clearance. Although, I do find it hard to believe that they haven't included any safety margin in the .060" clearance, if this is true, then I may end up with some problems. Of course, I can always just machine a little more out of the head. The only problem being that I am on the low end of seat pressure, so going any lower than 130 may be pushing it. The only advantage that I have is that I'm still running factory sized valves.

The .060 is the safety margin.. .030 is really tight and they are going to be smacking each other. .it doesnt matter if it runs for long periods at max rpms or not..will it work??probably. .will it last??probably not..

I dont understand how your changing seat pressure without changing the installed height? ?if you change seat pressure it should change the installed height and the open pressure. .

Im not risking it..thats for sure
 






What I'm saying is that I can change the install height and increase it from 1.6 to 1.630. That would give me the full .060." The problem with doing this is the decrease in seat pressure. It's 130 right now. that would take it down to 120 or so. That may be too low for the cam profile. I would have to go back to my notes to find out.
 






What I'm saying is that I can change the install height and increase it from 1.6 to 1.630. That would give me the full .060." The problem with doing this is the decrease in seat pressure. It's 130 right now. that would take it down to 120 or so. That may be too low for the cam profile. I would have to go back to my notes to find out.

Yea thats what i thought,it also would change you open pressure though. .

Id be nervous as hell with what milling you've already done to that seat pocket, especially in stock heads that tend to crack around that area. .i got spare stock heads in 93tm style and 95tm if you need them..lol
 






Called and talked to Tom today and ordered a set of 1.7 he said that he likes .60-.80 for cushion and said to take it off at the seat.said there is plenty of room

He also said you have the first set made and ill have the 2nd..i swear other people have been claiming to have these rockers but never report back,obviously they weren't telling the truth. .i really wish more people have used them before us..it appears we will be the genie pigs..

Let me know when you get yours running
 






Hey did you get adjustable pushrods with your kit??ever get it running
 






Ps...can we get a mod to move this thread to the performance section??? [MENTION=71]Rick[/MENTION]

I moved this thread to the need for speed sub forum. Hope this helps.
 



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I moved this thread to the need for speed sub forum. Hope this helps.

Thanks.think it will get more attention there
 






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