whypave

I am new to the site but I decided to join up after seeing what a great resource this is for late model GM small blocks. Lots of people from Pirate4x4 speak highly of this site.

I recently built an offroad buggy with an L92 engine and 6l80 transmission combination. it is setup with a car intake with injectors from Mast, Mast cam and ECM/harness and it was setup with an F-body car pan for a lower profile (packaging in the buggy).

Well the first time I tried to climb and obstacle with the buggy the engine lost oil pressure and it spun several rod bearings and damaged the connecting rods. I have an accumulator setup but it wasn't enough. I believe the problem was the farther forward setup of the f-body pickup in the pan versus the truck pan and the lack of baffling specific to our use. I've got a Kevko gated f-body oil pan setup to go back into the buggy so that should be resolved.

But what I'd like to discuss with anyone that cares to help a newbie is what parts should I consider upgrading for longevity while I've got the engine open. The engine is at a machine shop and he is well regarded but it never hurts to get more info. I'm not looking for more power at this point but stuff like good coated Clevite bearings are the types of improvements I'd consider. the machine shop says the block and crank are fine but I need to replace at least two connecting rods. So are there new rods I should be considering besides stock?

Thank you to anyone who chimes in to help me out!

WKMCD

iTrader: (2)

You'll want to add an Accusump when you get it back together.

Silver408z

iTrader: (1)

Rods are not going to make more power. If you arent going with big cubes or a power adder stock rods will be fine. There are alot of guys running power adders on stock rods with no problems. If you want to do something bearings while its apart I am sure it can only help. Not sure how much difference if any you will pick up from doing something like that though. It kind of sounds like you are at the point if you arent going to add cubic inches then go back with a stock rebuild.

cam

iTrader: (9)

These engines are not typically known for their lack of durability. The only unproven element to your whole build is the VVT system as its still pretty new and relatively ignored from a performance standpoint until this year when they started build L99 VVT engines for the new Camaro. MAST was pretty much the only company putting any effort into building GM VVT engines for hi-perf prior to this and their offerings are limited. Not saying anything bad about MAST dont get me wrong but one companies experience pales compared to the legions of folks soon to test the limits of these VVT set ups for hi-perf ( me included in that )

I'd agree with the last post that unless your looking to add a power adder or spray then stock replacement parts will do you fine. I'd upgrade all the fasteners to ARP or the like while you have it open though

whypave

Thank you for all the information so far. Cam you've got the intent of my question nailed. I'd really just like to know what parts I should consider upgrading from stock even if I don't want more power than I already have. ARP fasteners are a good example of that. Coated bearings are another. Connecting rods most often don't improve performance but since I need to replace two of them perhaps theres a reasonable cost aftermarket part I should look into. like the Titanium rods in the LS7 but I researched in the L92 sticky thread and those have a different stroke.

So I will probably just stick with 2 stock replacement con rods unless the machine shop has a better idea.

Thanks for the info so far!

cam

iTrader: (9)

Your most welcome. Good luck on the rebuild!

frito1

iTrader: (12)

I would love to see pics of your buggy if you have any handy. Thanks!

whypave

Here is the truck pan and the car F body pan with lots of bearing bits in it


here is a whole thread with tons of pictures.
http://www.pirate4x4.com/forum/showt...racing&page=24

Thanks

cam

iTrader: (9)

I just read some of your thread over there at pirate and it made me think of something else. I've been trying my DAMNDEST to find out what/if there are any differences between the LS7 lifter and the L92 lifters to no avail. From everything I've read they are the same but a few folks around here think they are different. I do recall reading about the LS7 lifter and how its designed specifically for high RPM usage and that probably means oil by pass or some kind of anti-pump up etc. Probably wouldnt be a bad idea in your case to swap out for a new set of LS7 lifters as well. They are a direct replacement meaning they will work fine with your stock cam and they're only $125 new for a full set from Summit or somewhere like Scoggin Dickey.

Seeing as you had oil issues I figure it couldnt hurt to mention you might as well cover all your bases just in case.

On a small aside I'm curious about the nec of that oil bypass valve in the stock truck pan myself? Im swapping an L92 into a car now and I do need the camaro pan for clearance but I could mod the truck pan by making one of the two if that bypass is an absolute requirement. Definitely interesting and has me thinking... Funny thing too as I posted in here to try and help you out and inadvertently your helping me now! Gotta love the internet

whypave

I have a Mast cam rather than stock but I will have to look into those LS7 lifters. In the thread on Pirate we have some discussion about that bypass and it is supposedly only needed with the newer L92s that have active fuel management or displacement on demand (why it has two names I don't know because the pressure can built up too high for the collapsable lifters or something. my lifters are standard LS lifters.

its also been recommended to me to drill small holes in the plastic part of the lifter piece that goes between a pair of lifters so that oil drains down before filling up the entire plastic area I believe.

Any opinions here to back that up?

If you need an extra truck pan to hack up let me know because I have that one available. I also have a complete L92 truck intake.

cam

iTrader: (9)

Yeah I did some searching this seems to be the perspective of the mere handful of people who have posted up about it so im going to just ditch it and hope it'll work out ok. I do have a stock L92 pan here if I decide to weld one up but thanks for the offer.

As for DOD/AFM acronyms? Marketing crap. Remember posi-trac? Suregrip? limited slip? etc. etc. all different names for the same damn thing LOL

posi won btw