sr arp main studs cracked oil pan, wtf? pics

[boost addict]

so i realized why my upper pan wasnt sitting right, and thats cause it was hitting the main studs. what the fuck? this is dumb and now im kinda stumped. anyone got an upper pan laying around? im giving arp a call tomorrow
http://i53.tinypic.com/293irnm.jpg
http://i54.tinypic.com/2bzax0.jpg

[Sileighty_85]

Did you modify the pan to clear the studs?

If not you have to.

Is it not written in the instructions?

[[email protected]]

hahah fuck! Mine was hitting so just grinded some material off of the oil pan. You should of noticed when you were bolting on the oil pan. I know there had to be a gap and it was harder and harder to tighten

[boost addict]

i know i wasnt paying attention, i noticed one side wasnt sitting flush with the block but i thought it was maybe the little dowel pin not fitting right. so wacked it with a mallet to seat it and that did it haha

[sr20sean]

yea youre supposed to machine them

[Bbsalexaz]

DERP DERP DERP.

That sucks in all seriousness.

[BiG MiKE86]

Ive got an upper pan - LMK willing to ship

Pan from S13 SR/Redtop

[boost addict]

hahaha i was waiting for that, cant blame ya though

[jr_ss]

Yep, clearancing is a must on the RWD SRs... FWD SRs don't have too.

[s14unimog]

^Wow.... so I just made a frantic call to my machine shop because of this thread; although you would think they'd catch this. I literately had them hold up on progress so my studs would come in; and I dropped them off last week. Luckily they hadn't gotten to that far this week.

Does ARP warn you about this? What's the preferred method; shorten the back 4 studs? Anyone know how much interference there is?

[boost addict]

no there were no instructions about this, nothing said to modify the pan. arp even told me they have nothing about it in the kit. im glad i was able to help you instead of it happening to you too. they say to hand tighten the studs in but im thinking if you turn them two more or so times youll be able to avoid this. ill try to represent which studs they are
this is with the motor upside down, the studs are on the "exhaust" side if you think of it that way
_____. . . .
back . . . . front of motor
____^^
those are the 2 that hit and the closet to the front is the one that cracked it

[s14unimog]

Right on, I'll advise the shop; props on the diagram, it's clear enough for me. Luckily I've got a second one but I'd like to keep that for the other motor. Can't you just weld yours back up?

[codyace]

http://www.codyace.com/albums/album448/parts52.sized.jpg

http://www.codyace.com/albums/album448/parts53.sized.jpg

You'll only need to grind the last too.


Shame it's not marked in the ARP instructions, nor is it really full on common knowledge (I mean who ever really thinks to search for 'pan clearence'.

There have been some guys who have lucked out, others have had the exact thing above happen. If you're not looking to trim the studs, you can always cut a hole in the pan there, and have a welder modify the pan to clear it too.

[codyace]

Yep, clearancing is a must on the RWD SRs... FWD SRs don't have too.

Some FWD do, some don't. I think it really depends on DE vs DET, as I've had some friends with DE have no issue, and some with DET that have also had to grind them.

[jr_ss]

Uni- go to nico and do a search for threads started under my name. I have a thread all about this and the modifications I did to make them work without cutting/grinding my studs.

[jr_ss]

Some FWD do, some don't. I think it really depends on DE vs DET, as I've had some friends with DE have no issue, and some with DET that have also had to grind them.

Well, I was referring to the FWD DE blocks...

[boost addict]

And uni take a look at my diagram again, I think it was a little messed up. It's the back two on that side. Like I said arp is sending me a few shorter studs so I'll see how that goes an I'll let you know. Maybe you can just do the same if it works out. Seems like it'll be the cleanest solution

[mewantkouki]

Buy mazworx studs that are stronger and already modified to fit and don't worry about silly shit like this. ;)

[codyace]

Buy mazworx studs that are stronger and already modified to fit and don't worry about silly shit like this. ;)

Albiet the fitting part can't be denied; I would like to see if there is any proof in superior performance from the Mazworx studs. That is, will the ARP blow up at random and the Mazworx prevent that from happening?

Mazworx makes nice stuff, but to say their main studs are THAT much better is a big claim.

[s14unimog]

You'll only need to grind the last too.Shame it's not marked in the ARP instructions, nor is it really full on common knowledge (I mean who ever really thinks to search for 'pan clearence'. There have been some guys who have lucked out, others have had the exact thing above happen. If you're not looking to trim the studs, you can always cut a hole in the pan there, and have a welder modify the pan to clear it too.

Wow... that looks like a few 100 thousandths. You recall how much was needed? That's sure to play a hand with those length tolerances.

Uni- go to nico and do a search for threads started under my name. I have a thread all about this and the modifications I did to make them work without cutting/grinding my studs.

Thanks, I'll give it a look. The guys up there are really good so I'm sure they'll sort it well.

And uni take a look at my diagram again, I think it was a little messed up. It's the back two on that side. Like I said arp is sending me a few shorter studs so I'll see how that goes an I'll let you know. Maybe you can just do the same if it works out. Seems like it'll be the cleanest solution

That would be nice to get some shorter studs now... I'd be interested in keeping that hexagonal socket. Let me know how that works out. I wonder if I can get a pair myself. Shit, they can have the other two.

Buy mazworx studs that are stronger

yeah, I don't know about that now... bold statement.

[S14DB]

Mazworx kit is made from ARP2000 not the 8740 chrome moly that the regular ARP kit is made from.

[mewantkouki]

^ ding ding ding

http://www.mazworx.com/product/engine/nissan/nissan-sr20detsr20ve/hardware/mazworx-sr-main-stud-kit

[codyace]

Mazworx kit is made from ARP2000 not the 8740 chrome moly that the regular ARP kit is made from.

I knew what ARP still made them, however I was looking for quantitive data on how they were worth the price, especially considering DET main bolts are plenty strong.

[codyace]

^ ding ding ding

Mazworx SR Main Stud Kit - Engine - Mazworx (http://www.mazworx.com/product/engine/nissan/nissan-sr20detsr20ve/hardware/mazworx-sr-main-stud-kit)

Either way you haven't proven what I knew. Show me where traditional ARP/DE/DET/GTiR main studs have failed.

EDIT: Not trying to be a technical asshole, but there are countless/many/hundreds of cars running big power on stock stuff without any signs of failure. If anything the SR mains are pretty stout, unlike the rod bearings.

[mewantkouki]

I never said arp or stock stuff was prone to failure. I think you misinterpreted my original statement. I have stock main studs on my SR and have even re-used stock head and main studs on other engines. However pre-cut studs that are made from a stronger material is an easy solution the the cracked oil pan problem. Yes I realize you can modify arp fasteners to fit and correct the problem but not everyone wants to cut a main stud when there is a kit that is modified and ready for installation readily available. The fact that they are made from arp2000 material is a bonus. I'm sure you can see that. If you really wanted to pursue the difference in tensile strength between the two fasteners I'm sure mazworx could provide you with a ton of information and real world application that suggest that arp2000 material is stronger than the 8704 Chrome moly used in the other fasteners. There must be a reason for them requesting that arp produce the bolts and I'm fairly certain they use them in their crate motors and drag car. Let's not argue semantics.

[S14DB]

I have never stretched main bolts. The only ARP head studs I have stretched were on a Turbo Diesel where the cyl pressures are a lot higher. This was the only situation where the ARP2000's were needed. Like you said the ARP2000 is a bonus. Not necessary but when you want the best... The only thing I would use ARP2000 on our motors is the rod bolts.


I'm not a big fan of main studs. Have to check the main bore because the clamping load is different. The Nissan OEM units are a high grade steel(4130 IIRC) and up to the job. Sure some of the old domestic stuff used bolts that weren't as high grade as today. But, just because they need them doesn't make it a necessary upgrade on modern engines.

[sean350z]

Not trying to be a technical asshole, but there are countless/many/hundreds of cars running big power on stock stuff without any signs of failure. If anything the SR mains are pretty stout, unlike the rod bearings.

Stock mains or die. Well said

[codyace]

There must be a reason for them requesting that arp produce the bolts and I'm fairly certain they use them in their crate motors and drag car. Let's not argue semantics.

I wasn't looking to argue anything, other than the Mazworx stuff is over engineered and isn't going to work any better/worse than OE DET stuff. Much as said above, it's over engineering something that is already overengineered.

Nothing against Mazworx, they make nice stuff, but don't fall into the consumer trap of 'because XXX does it, that means it's the only way'


But, just because they need them doesn't make it a necessary upgrade on modern engines.

Which was exacty the point I was trying to make. Upgrading for the sake of ugprading is a waste.

[s14unimog]

so back on topic, how much interference is it? Shit I'm only swapping to these b/c its a "while I'm in here, I can afford it, it can't hurt" upgrade; lol.


S14DB, the difference in clamping forces is that different between the two?

[S14DB]

so back on topic, how much interference is it? Shit I'm only swapping to these b/c its a "while I'm in here, I can afford it, it can't hurt" upgrade; lol.


S14DB, the difference in clamping forces is that different between the two?

Shelf stock is a 8740 chromemoly steel and have a 190,000 psi tensile-strength rating. The ARP2000 have between 200,000 and 220,000 psi tensile-strength rating. Not a huge gain

The benefit of the ARP2000 is that it's more ductile. Which makes it ideal for head studs and rod bolts. Less likely to have the head lift or a rod cap break loose. Mains are more set and forget. They don't have the stretch loads that the others do.

[jr_ss]

so back on topic, how much interference is it? Shit I'm only swapping to these b/c its a "while I'm in here, I can afford it, it can't hurt" upgrade; lol.


S14DB, the difference in clamping forces is that different between the two?

I would say it's close to an 1/8" of interference, definitely not more than that though... It was a pain in the ass to clearance though. I think I pulled the upper pan more times clearancing for the mains, than I ever will in a life time.

[codyace]

I would say it's close to an 1/8" of interference, definitely not more than that though... It was a pain in the ass to clearance though. I think I pulled the upper pan more times clearancing for the mains, than I ever will in a life time.

It is VERY close. 1/8th is a fair estimate.

[s14unimog]

Shelf stock is a 8740 chromemoly steel and have a 190,000 psi tensile-strength rating. The ARP2000 have between 200,000 and 220,000 psi tensile-strength rating. Not a huge gain

The benefit of the ARP2000 is that it's more ductile. Which makes it ideal for head studs and rod bolts. Less likely to have the head lift or a rod cap break loose. Mains are more set and forget. They don't have the stretch loads that the others do.


Good info, but I was referring to your comment about checking crank bore clearances with the aftermarket hardware.

I'm not a big fan of main studs. Have to check the main bore because the clamping load is different.

[jr_ss]

Good info, but I was referring to your comment about checking crank bore clearances with the aftermarket hardware.

Ideally, you'd want to line hone your mains with the ARP's trq'd down. Since they provide a greater clamping load, they augment the OEM dimensions. It's not necessarily needed, but not a bad thing to have checked out. I didn't, but probably should have. Next motor I suppose...

[s14unimog]

No I understand what he means but I just question there being a difference. If the cap is bottomed out, it's bottom out; no? My motor will be checked and assembled with them but I just thought in general if the cap is down its down.

[jr_ss]

Well, generally speaking, studs have a higher clamping load than bolts. This can cause some distortion in the caps. I'm not saying by any means that it is or will happen, but there is a greater chance using studs rather than OE bolts.

[smelly240]

this has been documented - i can see how it can be overlooked tho - you dont think to look for "install instructions" for main studs... I have a special tool i made out of a valve and it works awesome for clearance of the oil pan.

[S14DB]

Well, generally speaking, studs have a higher clamping load than bolts. This can cause some distortion in the caps. I'm not saying by any means that it is or will happen, but there is a greater chance using studs rather than OE bolts.

It's more that the clamping load is at a different angle with a stud and nut compared to a bolt head. It's even more noticeable with rods when switching from a bolt to stud. Why a lot of rods use a bigger bolt rather then studding them.

All caps deform when you tighten them. Why you have to check the bores tq'd to spec rather then just in place.

The difference in deformation between bolts and studs isn't always great enough to oval the caps out of spec. But, it is something you still want checked with a bore gauge to make sure they are round.

[s14unimog]

just to add a bit more to this thread. I spoke with my machinist this morning and he told me that he had to counter bore the girdle 0.150" and remove approximately the same amount from the stud... This is quite an interference. I also spoke with a representative at ARP, Sam Benson, and he said that the only bolts they stock that are a 1/4" shorter are actually made from a different material. He did not feel comfortable supplying those for that reason, but said if I insisted he would. He recommends parting them off in a lathe, with coolant, as opposed to a friction cut as to have less heat put into the studs. This is surely valuable information for those who intend to deal with this in the future.

[lewisfk]

Did you modify the pan to clear the studs?

If not you have to.

Is it not written in the instructions?

i have arp main studs and i havent installed my pans yet! how do u modify the pan? Is it simple thing i can do or am i better of taking it to a machine shop! My bottom end was lined bored with arp mains!

[boost addict]

i wouldnt take any off the pan cause i dont think theres enough material, take it off the studs

[s14unimog]

^you couldn't, as I stated there is approximately 0.300" of an inch clearance needed. You would need to fabricate reliefs, and weld them on, if you intended to go that route.

[kouki_drifter]

i think my motor is suffering from this problem its a brand new rebuild, the driver side rear of the "oil pan" has a small gap i put 2qts of oil in it to check for leaks before i install it good thing i did, i have arps installed i didnt think to check clearance. im going to pull the pan tomorrow and asses the situation i dont think the pan cracked i hope not any way i will post pics i got a dremel tool so i will trim the rear studs a bit and see how it goes good thing i used the search button and found this tread!

[kouki_drifter]

fuck! mine is cracked to! does anyone have an extra one or do you think JB weld would work?

[Kingtal0n]

fuck! mine is cracked to! does anyone have an extra one or do you think JB weld would work?

Do not use JB weld, lol :wtc:

[s14unimog]

fuck! mine is cracked to! does anyone have an extra one or do you think JB weld would work?

The only reason JB Weld is still in business is b/c everyone tries it at least once. DON'T do it. It will surely leak. Find a shop in your area and weld it up. If not, shoot me a PM and I have an extra I could sell ya.

[kouki_drifter]

^^^ cool man thanks! I had it welded earlier lets see how it holds up I might still be interested in the one you got, I'm gonna put a couple quarts of oil in it and see how it goes pm me a price for yours just in case. Also I might need a I guess you could call it a "main seal retainer" the one on the rear of the block, because I guess the studs hitting the pan put pressure on the little bolts and when I tried to take um off they just broke right off and I noticed that there was a little oil seeping out of the bottom of the seal so im thinking it might of warped it and caused a gap at the bottom between the seal and the crank fucken beautiful! Lol so if anyone has one laying around let me know

[kouki_drifter]

O and I did trim the studs down 3 of them the rear 2 and the one right in front of the rear one on the exhaust side so good to go

[kouki_drifter]

it held up good motors in the car running great!