06 LJ Randy Rebuild

[akadeutsch]

Just great work. Using the older intake for equal size runners was a good idea. I'm just curious why there appears to be a step from the brick shaped manifold that you welded to the older intake where it meets the runners? The added manifold appears larger than the runners. Wouldn't you want them matching size to minimize drag and maximize velocity?
Everything in your build appears to be well thought out and I don't doubt there is a reason. I just don't see it yet. So, i'm only curious how/why you chose the volume of the manifold you joined to the old runners/manifold? Again absolutely astonishing work. I can't wait to read the data. Id like to know about the equipment you used to weld braze solder or whatever it took to get that result... cheers! Great work!
and thanks for all the pictures.

[Randy Bobandi]

I'm just curious why there appears to be a step from the brick shaped manifold that you welded to the older intake where it meets the runners? The added manifold appears larger than the runners. Wouldn't you want them matching size to minimize drag and maximize velocity?

So, i'm only curious how/why you chose the volume of the manifold you joined to the old runners/manifold?

This is a turbocharged engine. General rule of thumb for plenum volume is 1:1 (displacement:plenum) volume for NA engines, 1:1.5 for power adders.
Though there other factors involved, other than displacement, like max torque RPM range and especially space in the engine bay. The plenum volume I ended up with is 290 cubic inches, just over the engine displacement. There isn't much more room to go larger than that without mounting the engine on a slant. The dang steering shaft is just a couple inches from the intake plenum.

I'm not concerned at all about the "step". The step is the plenum flange from the OE manifold. Most all inline engine manifolds are constructed this way and it would be extremely difficult to weld the OE runners to a plenum without that flange. The OD of the runners for cylinders 1/2 and 5/6 are 1/4" from eachother. They would have to be welded to the plenum from the inside out if you remove the flange from the OE manifold. The other way to go is to just build a totally custom intake, which requires buying a $250 intake flange from Newcomer. That's more than I spent on this whole setup including the throttle bodies.

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Id like to know about the equipment you used to weld braze solder or whatever it took to get that result.

I'm not using anything uncommon. I use the tried and true, YesWelder 205DS-B with a teflon liner in the traditional mig gun. 100% Argon. ER4043 wire which is preferable to 5356. 5356 is more likely to crack after several heat cycles.

[Randy Bobandi]

I am currently in the middle of the development of Jeep/AMC straight 6 Roller Camshafts. The first grind is only a couple weeks out.

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There are important things to keep in mind when converting this engine to a roller cam. This is a public service announcement.

1- This will be expensive. None of the major camshaft grinders have ever wanted to jump on board. I had to go to the guys that machine custom Tool Steel NHRA Top Fuel camshafts. Jesel and Militia Racing Products are the only two companies that found this project interesting and doable. The camshaft itself will cost $1,700.00. No refunds, but they can obviously be reground several times if necessary. Considering the cost, this conversion is not well suited toward a mild or stock grind. Flat tappet cams work great for that. This project is geared towards aftermarket EFI, turbochargers and goals of 1000+ HP.

2- Getting roller lifters with an anti-rotation mechanism into the lifter bores of these blocks is not simple. Roller lifters are typically 3" tall so you can't snake connected tie bar lifters into the bores. Dog bones could work but there isn't a great way to fasten dog bones into the block. They would call for an experienced machinist to come up with a good dog bone solution. Keyway lifters would work great but they're only available as a solid lifter, also installing the keyed bushings is very expensive and not really a project for the home garage. What we'll end up with is a custom tie bar solution. Well, it's really a modified tie bar. The tie bars will be riveted to one lifter and slotted on one end so you can snap them onto the other lifter while they're in their bores.

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3- The camshafts are the same material that they use in top fuel engines. The manufacturer doesn't want any other material but bronze used for distributor gears. Guess what? Nobody makes a 4.0L distributor gear in bronze, they're all iron. We have found bronze gears that will work however. Turns out, the Mopar R5 engine uses the same gear as the Jeep engine. Although, the Jeep distributor shaft is about .040" larger than the R5's. So you'll have to drill and hone the R5 bronze gear to .5285" and it will work just fine. You may want to have some spares and keep an eye on wear because you'll now have a bronze gear driving the oil pump. Or you can always go to an external pump.

4- The distributor gear may only sync up with the late model 99-06 EFI systems. It may not work with an actual distributor, The gear on the iron cast cores is indexed to a specific degree and getting the gear indexed properly presents a whole set of problems for the machinist. However, the gear is indexed due to the distributor not being able to turn 360 degrees. The fastening tab is cast into housing of those early model distributors. I think if you grind that tab off, it can then be clocked freely and fastened with an external tab.

If you guys have any thoughts on this project let me know. Especially with the lifter anti-rotation mechanism.

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[Randy Bobandi]

Waiting for the roller cam to come in. Should be in this week. I got the ignition coil setup figured out with a slab of 5/16 aluminum plate, a fat 3/4" carbide burr and some odds/ends.

coilkit.jpg

To avoid replacing burned up IGN-1A coils every 3 months, the GTR coils are becoming the peoples choice. Twice the output of an LS1 coil, half the heat of an IGN. This coil kit is fitted with NGK 49025 coils, SPP208E boots for the 2JZ and BCPR7ES NGK plugs. (OE GTR boots are a little longer than the 2J)

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[Randy Bobandi]

Roller Cam is in...

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[dwg86]

I just stumbled across this thread. Awesome build!

[Randy Bobandi]

A whole bunch of heavy metal going together without issue.
Main Bearing Oil Clearance - .0028
Rod Bearing Oil Clearance - .002
Cam Bearing Oil Clearance - .003
Piston to Wall Clearance - .0025 (Coated (.005 without Coating))
Ring Gap Top - .028"
Ring Gap 2nd - .028"
Tappet to Bore Clearance - .0015
Crankshaft Endplay - .004
Camshaft Endplay - .004

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[D'sJeepWrld]

I am completely amazed at the extensive work you have done man,The word amazed is an understatement
My jaw has been dropped as I've been reading all of this and seeing it ,This is awesome !

[Randy Bobandi]

I've been reading all of this and seeing it ,This is awesome !

Thanks brother.

I'm just waiting on a new set of pushrods to finish it. The roller cam requires .300" shorter pushrods due to reduced base circle diameter.

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[Randy Bobandi]

This unit is pretty much ready to roll. I had a guy on Etsy make a custom classic AMC badge for the valve cover. Now it's time to hang it between the frame rails and build the turbo kit.

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[D'sJeepWrld]

This unit is pretty much ready to roll. I had a guy on Etsy make a custom classic AMC badge for the valve cover. Now it's time to hang it between the frame rails and build the turbo kit.

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Oh hell yeahIt looks so awesome man
Question,Although I got many but I'll figure em out till then,Why wouldn't/didn’t you go with the edelbrock aluminum head ? I have that head sitting on my shelf of parts for my build I'm planning (daily driven 4.8L stroker 4.060" crank)
Apart from the price what would be a reason not to go with it ? I'd understand warping under boost but I don't plan on running +1000 Hp like Newcomer racing did!

[Randy Bobandi]

Why wouldn't/didn’t you go with the edelbrock aluminum head ?

That cylinder head offers no significant advantage. All Edelbrock did was copy the OE casting and shrink the combustion chamber. I guess you could argue better thermal efficiency due to the material and maybe be able to run more ignition timing. We know for certain that it's not a superior design for porting. Though it's definitely easier to port the aluminum casting than iron.

My primary concerns are holding 30# of boost pressure and valvetrain stability over 7000 RPM. The iron heads are clear winners in those respects.

If we had an aluminum head available that was designed properly, I would be all over it. Imagine if there was casting with massive ports, 2.150" intake valve, a 3/4" deck and a rocker shaft or provisions for a huge one-piece rocker stand. Imagine if there was a completely redesigned head like a Hemi style or BBC style configuration. We don't have that unfortunately. We just have an aluminum version of the stock head.

[D'sJeepWrld]

Why wouldn't/didn’t you go with the edelbrock aluminum head ?

That cylinder head offers no significant advantage. All Edelbrock did was copy the OE casting and shrink the combustion chamber. I guess you could argue better thermal efficiency due to the material and maybe be able to run more ignition timing. We know for certain that it's not a superior design for porting. Though it's definitely easier to port the aluminum casting than iron.

My primary concerns are holding 30# of boost pressure and valvetrain stability over 7000 RPM. The iron heads are clear winners in those respects.

If we had an aluminum head available that was designed properly, I would be all over it. Imagine if there was casting with massive ports, 2.150" intake valve, a 3/4" deck and a rocker shaft or provisions for a huge one-piece rocker stand. Imagine if there was a completely redesigned head like a Hemi style or BBC style configuration. We don't have that unfortunately. We just have an aluminum version of the stock head.

Yeah man i completely agree with you! I just somehow suckered myself into the rabbit hole of "Well i dont see myself spending money to rebuild a stock head so this new Eddie head sounds like a good alternative....Ooooooo nice....thermal efficiency more timing,more power i guess" but yeah in a sense i kinda regret my purchase especially since i could've gotten me a nice ported head from newcomer considering what i paid for the Eddie head but at the time and given the situation i was in the eddie head was cheaper and it was supposed to be on my LJ as of right now but then i said "Nahhh....ill use the new head on the stroker i plan on buidling) so i ported the stock head as i waited on my ARH Headers..... that was about 5 months ago? But i digress!
But yes that would be friggin amazing if one could go to Summit racing and get a head with all the goodies Big ol'e ports,thick deck and a different rocker provisions! HOWEVER a gentleman on facebook about a month ago " John Brown" from the "Jeep 4.0 inline performance" page. I spoke to him and IIRC he told me that he runs a BBC shaft rocker setup on a eddie. head,I know he was that style setup on the eddie head after alot of machine work to make it all happen! Pretty awesome guy!!! Shed some light on some stuff i didn't know much about! But Id give him a message to see if he can get that style of rocker on a jeep head for you ! I havent even bothered to even ask how much he'd charge since im just some broke 20 year old so to not come empty i just dont ask. i only got enough to rack up the parts i need here and there to then hopefully be able to put it all together someday, Hopefully in a year i can atleast have an N/a 4.8 stroker dream come true Turbo and different trans. can come later XD !

I don't ever see myself revving my LJ out to 7k...a 42rle wont like(it already doesn't like what it sees)and even if i could....It would see 7k rpm everyday from me. given the cam harmonics ive heard about, the engine wouldn't last me long....so longer stroke and keeping it under 5500k Rpm it is for me&my daily application, But i would be slightly concerned with head warpage once i decide to go with a turbo, Id want/love to run one and better yet! Make a turbo kit for my LJ and go standalone (most likely haltech) But that'll take place once I get a different tranny that has its own controller and not one like a 42rle that depends on the same computer as my engine controls....

[Randy Bobandi]

a gentleman on facebook about a month ago " John Brown" from the "Jeep 4.0 inline performance" page. I spoke to him and IIRC he told me that he runs a BBC shaft rocker setup on a eddie. head,I know he was that style setup on the eddie head after alot of machine work to make it all happen!

Big blocks don't accept full-length shaft rockers because of the twisted wedge design. They're usually equipped with individual shafts per rocker arm, with a one-piece rocker stand.

bbcshaft.jpg

The Jeep head is an inline pedestal mount like an LS. Crower has been known for a long time to make an excellent full shaft rocker system for the LS. Why Harland Sharp decided to go with the tiny 5/16 shaft per cylinder is an odd choice. The Jeep head could easily accept a full length shaft like the Crower system.

LSshaft.jpg

The next best option is a full length rocker stand, like the OE LS system. That's what I did on this engine. I fabricated a full length stand and welded the Harland Sharp pedestals to the stand. So the entire valvetrain is locked in place, with the added support of the "per-cylinder 5/16" shafts" from Harland Sharp.

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I also removed the silly orange anodizing from the Harland Sharp rockers, but that's another topic.

[D'sJeepWrld]

a gentleman on facebook about a month ago " John Brown" from the "Jeep 4.0 inline performance" page. I spoke to him and IIRC he told me that he runs a BBC shaft rocker setup on a eddie. head,I know he was that style setup on the eddie head after alot of machine work to make it all happen!

Big blocks don't accept full-length shaft rockers because of the twisted wedge design. They're usually equipped with individual shafts per rocker arm, with a one-piece rocker stand.
bbcshaft.jpg

The next best option is a full length rocker stand, like the OE LS system. That's what I did on this engine. I fabricated a full length stand and welded the Harland Sharp pedestals to the stand. So the entire valvetrain is locked in place, with the added support of the "per-cylinder 5/16" shafts" from Harland Sharp.
LSstand.jpg

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I also removed the silly orange anodizing from the Harland Sharp rockers, but that's another topic.

Excuse the late response,For some reason my phones&wifi IP is blocked on here so I've been up and down looking how to get past that.....anyways back to the subjects in hand

Yeah man you're more than correct on that! when I actually think about it....I mean I've worked on Big block chevys so theres no way to fit that'll fit but I digress, I just know that "John Brown" runs a rocker setup that requires him to run 2 valve cover spacers! Why ? Well I don't know since I didn't get too indepth with the questions on that topic since he was on a time limit and i was mainly interested on oiling and running a Dry sump setup and why the #1 rod always seems to sling out the block,cam harmonics Etc.

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Edit- Also I was also wrong about him running an eddie head,He talked about it but the picture tells me otherwise! Memory didn't serve me too well....

Also any real advantage apart from Newcomers rocker setup apart from it being pretty,already a raw aluminum part... To me it looks like a Harland sharp rocker but it looks like they took it and saved weight here and there by machining it in certain spots which Is kinda cool,But it doesn't look like it'll be a true benefit to my specific application but saving weight where you can should help as far as the valvetrain goes ?
I'm glad I'm not the only one that doesn't like the orange anodizing causd it looks cheesy as hell to me. What do you use to remove the anodizing,On my rc cars I've found that "Greased lightning" works pretty well to remove anodizing on parts !