Dave is THE best!!!!!

 

Why not just use stock bolts? Are you increasing the power significantly?

 

That was consistently my experience. They didn't want to commit to any kind of answer about most things. Not sure if it's a fear of litigation in the event an expensive engine lets go due to their advice, but it got frustrating.

Amusingly, the hardware I used was what was advised to me by ARP after filling out forms with all the measurements of the thread holes in the block, including the block material, which they even referenced in the reply, so I guess the person you spoke to disagreed with the person I did?

Either way, bit late now, and the engine hasn't blown up yet, so whatever, I guess.

I've also remembered I had a conversation with someone on Facebook about the seller of the bolts and problems he was also having, so I don't think I should name him here because I'm not entirely comfortable recommending him without this caveat, but I can't vouch for the accuracy of the info. I'll PM you.

 

That's very kind of you to say - this forum has a lot of members that contribute good stuff If anything I'm behind on a few threads on some things I've been up to recently...

 

Really not planning on going too crazy with it. I already have an upper SC pulley, and assuming I can afford it after all the engine parts/swap issues are taken car of, I'm planning on a lower crank pulley and a tune...which should be good for 600-625HP (give or take)

The biggest issue is the fact that I've purchased all new rods, pistons valves etc.... (Long story short I thought I could rebuild my NA engine into the SC version, but it turns out the blocks have one or two extremely small differences....hence the engine rebuild.

The new rods came with new bolts, but they don't appear to be a quality product. The heads aren't stamped, and I have my reservations about their longevity. I've used ARP many times before during my rebuilds and I'd like to stick with them if at all possible. Plus, if I use the same material ARP bolts all the way around, the overall "strength" of the engine will be uniform. I know it's silly, but I'm a firm believer in everything matching across the board. I have issues...I know this!

 

@davetibbs I got your email about the rod bolts, thank you VERY much! Unfortunately, my account isn't able to email you back through the system....so I'm posting my thanks here!! FYI, I'm going to reach out to Pavel this afternoon! Hopefully he'll just sell me the bolts, cause that's all I really want! I'm not a fan of mailing parts off....I like to be able to go to the shop and put eyes on them....as well as the machinist when they're dragging their feet! LOL!

 

I have rebuilt 4 of these, all SC model. Was not aware there were block differences, do you know what the differences are? Would be interested to know. I had one block repaired with a new liner but I was tempted to try to use a NA block as I thought they were the same. I know the heads are different. I have always reused all bolts except the head bolts, don't see a need to change any others personally. And I think I reused them on one engine.

 

Unfortunately, I don't know what the differences are. What I do know is that the blocks have different part numbers from JLR....literally, they're off by the final digit....and it's only off by 1. I've also been talking with a gentleman in CA who rebuilds a lot of these, and he confirmed that you can't use the NA blocks for the SC engine. Full disclosure, I found his advertisements on eBay and craigslist advertising his rebuilds. I called him looking for parts, but ended up getting a lot of advice.

Much like @davetibbs warned about the gentleman who he received some parts from, I feel as though I too should put a disclaimer. I have not put these blocks side by side, I am only going off what I have found, and what I was told. I can't confirm it 100%. I will say this though, I have found identical parts across both engines always have the same part number, so my suspicion is that if JLR had different part numbers, it was for a reason....I just have no idea what that reason was.

Wow! So you reuse all the main bolts? I'm tempted to do that now...at least it'll get this project back moving forward!

Out of curiosity, do you happen to know the torque specs for the M10's, M8 shoulder bolts and external M8 bolts? Plus, any idea what part number/where do you get new siliconized washer gaskets for the external bolts?

Thanks again for all the help guys, to say I was a little defeated last week would be an understatement.

Oh yeah, I forgot to add, ARP did commit to head studs for this engine. The part numbers they gave me to use are: ATP8.000-1LUB, with the washers: 200-8510 and the nuts: 300-8303.

 

The SC engines have oil spray jets to cool the undersides of the pistons and the NA block doesn't, I haven't ever seen the inside of a NA block to know of any other differences off the top of my head.

RE bolt reuse: Since the main bearing/conrod bolts are torque-to-yield they have a max number of tightening sequences they can go through before they stretch or snap. That's why the rebuild guides (which exist for the 4.2 but not the 5.0) are careful to state that you must mark the head of the bolts with a punch every time you tighten them, and replace after a certain number. Assuming one tightening at initial engine assembly you've got probably 2 more before you should be changing them out. Given the effort and expense to rebuild, a lot of people (myself included) don't find much point in saving (relatively) a few bucks and reusing bolts, but it's obviously possible. In my case, when I rebuilt the engine I couldn't find anyone who'd sell me the bolts at the time, so I decided to go ARP (even given subsequent disagreement over the specific hardware suitability) because you do not have a limited number of times you can tighten them, which allowed me to go through multiple torque sequences as I measured everything and assembled.

 

[QUOTE=davetibbs;2461602]That was consistently my experience. They didn't want to commit to any kind of answer about most things. Not sure if it's a fear of litigation in the event an expensive engine lets go due to their advice, but it got frustrating.



Amusingly, the hardware I used was what was advised to me by ARP after filling out forms with all the measurements of the thread holes in the block, including the block material, which they even referenced in the reply, so I guess the person you spoke to disagreed with the person I did?

Either way, bit late now, and the engine hasn't blown up yet, so whatever, I guess.
[/QUOTE

So, somehow I missed this post!

That's hilarious that I went through the exact same process and they told me nothing would work for the mains! I even asked asked about the M8 bolts too!!!! They told me there wouldn't be enough thread engagement for aluminum. While the jury is out on the 201-4302 studs I was thinking of using, I looked at the measurements and the M8 bolts you used have almost the exact same amount of thread as is in the block itself. (FYI, the studs in the 201-4302 kit are individually AM4.500-2B, basically the same as yours only 4.5" long). They did tell me the AM4.775-2gb studs you used are "a bad part number." So my guess is that they don't make them anymore? Or they're just out of stock and didn't want to tell me. It's a little frustrating as I too filled out all the paperwork and sent it to them.

I did find out why they don't recommend any of their rod bolts. I guess all the arp rod bolts in the 3/8-24 pattern have a shoulder just below the bolt head that is .374" wide by .15" tall....and the rod bolt holes are exactly .360" wide....so I could thread them, but never seat them unless I machine the rods....which makes me a little nervous when dealing with FSR's.

 

I couldn't agree more! While this is my first go round with the JLR 5.0 block, I've rebuilt many a' engine in my day. I've seen some TTY bolts get torques over and over and over with no issues, and then I've seen some snap before they even get halfway torqued on their second use....sometimes even their first.

As you said, I've spent so much money on this project/rebuild I can't turn back, and I've learned from some rather embarrassing experiences that cutting corners leads to disaster! Unfortunately, because I'm transplanting this into a different platform, I have a lot of additional swap costs....although it appears as though A LOT of the swap parts I've purchased will ultimately be unnecessary. That said, since this is a Jag forum and not the LR forum I've been posting to about this project I'll stop myself from going on and on about what I'm doing and stick to the engine! LOL!

 

I can't remember the torque I used on the mains, if it wasn't published I think I asked my race engine builder what he used typically for those size bolts and used that (he doesn't typically replace bolts either). The external M8s I think I did to 30 ft/lbs but that is from memory. I was amazed to find I had some of the washers in stock from years and years ago when I did my apprenticeship at a diesel test equipment manufacturer in England. They were exactly the same so must be an off the shelf part. Maybe try Grainger for them.

 

Sorry for the delayed response, my computer literally died overnight....not sure what the heck went wrong with it. Luckily, I had the PC I use for all things JLR software related, but migrating accounts and what not has been a bit of a pain....especially going Mac to PC...but, I'm back up and running for now!

Thanks for the advice! If it comes to it, I may end up re-using the stock bolts. That said, I do have ARP stuff for everything but the M10 mains....I even have M11 head studs for it....errr...well, I'm going to order M11 head studs for it, but ARP has given me a compatible part number!

I did email ARP back to ask what sort of thread engagement they were looking for in aluminum, and the rule of thumb they sue is AT LEAST 2.5 times the diameter. So, in the case of M10 studs, 25mm of thread engagement would be a minimum. Which after measuring my AM4.500-1LB, they have almost exactly 25mm of thread on them. (FYI, I also have some 3.75" studs and they too only have 25mm of threading on the m....and why I have these is a long story, but the cliff notes version is I ordered the wrong BMW main kit...and no, they're not all the same...insert yet another facepalm here)
Assuming the AM4.775-2gb's were the same, they will work as far as engagement is concerned, but since the block has approximately 44mm of material threaded, the stud will falsely bottom out prior to seating all the way into the block...assuming the stud main shaft is slightly larger than the threaded section. Which is a shame, because when I measured my block, I've got a total M10 main bolt depth of 4.2". which when put together with the washer and nut height of .52" give a total length of 4.75"...ish. So, in theory the AM4.775-2GB's should have been perfect! I should also note here they're on back order everywhere I can find them.

Seriously, this should not be this hard!

 

With 4 bolts on each main these engines are incredibly strong, as you know most engines only have two bolt mains, even race engines producing similar power figures. So standard bolts should be just fine, probably why ARP don't bother to offer a replacement.

Torque figures:

 

I can't thank you enough for the main torque specs/sequence! Thank you! I've been putting a few fires out lately, but I'm about to get into the rebuild 100% this week.

One other question, does anyone have the stock rod bolt torque specs/sequence? I have come up empty WRT the ARP bolts there as well....unless I machine the rods to enlarge the bolt holes enough to accommodate the "shoulder" of the ARP rod bolts....but that's a lot of work and potential for screw up when I can just use new OEM bolts.

I think the specs are somewhere in the 4.2 V8 manual? Cause I can't find them anywhere in the LR/RR manuals. But I can't locate the 4.2 V8 manual either.....

Why has JLR made it so hard to find information on these engines? Oh wait, the less people know, the more $$ we'll have to pay JLR to work on them!

 

See attached specifications which contains torque specs for the main bolts listed above but also the connecting rod bolts.

A lesser-known fact: the custom ARP bolts I purchased for my connecting rods were actually for the 4.2, but despite the design of the 4.2/5.0 conrods being different, the bolts used are actually the same specification, meaning you should still be able to order 4.2 bolts from JLR - they generally don't list any internal parts for the 5.0 block for purchase.

 

Also please see attached for 4.2 rebuild manual

 

Hey @Davetibbs! Thanks for the specs! I have most of those in my RR manual, but they leave the rod and main bolts out!

You're absolutely right, I've found the OEM rod bolts on a couple different sites, and truthfully, I may go with them. I have new rods for my engine and they came with new rod bolts, I just don't know how good/bad they are and as such was trying to swap them.

Oddly enough, the rod bolts are 3/8-24 thread pitch....which threw me off as they're not a metric thread pattern. Again, the only real issue with the ARP bolts I found is the shoulder on the bolt. It's only .1" tall and the diameter is only .014' wider than the rod bolt hole (.374 vs .360)....but it's enough to keep it from seating unless you machine the rods ever so slightly!

 

While 4 bolt mains are nice they are quite a ways from the strongest bottom end. Even some plain old Ford engines use cross bolted mains which have 6 bolts per cap. MUCH stronger than any 4 bolt main. Note that 4 bolt and cross bolt mains have been around for a VERY long time so their benefits are well known but it is the cost that drives their use.

Much like the piston oil squirters which are very common now but were pretty rare. The benefits of oil squirters are now realized and the manufacturer's have added them to a lot of engines. The increase in FI which massively increases the heat load on the pistons is another factor in making them common nowadays. I have even seen instructions on how to add squirters to your block.
Installing Oil Squirters
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.
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@Davetibbs, did you do any sort of machining for your M10 main studs? I'm curious how far you were able to seat your studs in the block.

I've found that the best fit for my block are the ARP M10 AM4.000-1LB. They provide the perfect fit due to the fact that I can't actually seat the stud all the way into the block due to the "shoulder" of the stud. You should be able to see the larger center section of the stud. Granted this equates to greater strength, but the trade off is the fact that I only have 1" of thread engagement vs. the OEM 1.8" of thread engagement. I found the AM4.600-2LB had the exact same shoulder issue, and when fully seated in the block the center section actually extended beyond the main cap....and hence they won't work.

Pictured is the stud I'm using to show the "shoulder" on it:


AM4.00-1LB

I've also included a picture of the AM4.300-2LB I also tried, but even though it has the "skinny" center section, I am unable to thread it past where the threads stop on the stud itself, and hence it doesn't fit this application.


AM4.300-2LB


I've toyed with the idea of machining the block a little to accept a thread sleeve such as the one I'm using for the M11 head stud conversion:

https://www.huhnsolutions.com/jaguar

But, I think at this point I'm just WAY over doing it especially since I'm not going crazy on this engine. Now, I just have to answer the mental question of whether the extra strength of the stud is a better trade than the double thread engagement length of the OEM stretch bolts.

I need to make up my mind though, as I'm trying to get the block to the machine shop early next week!