Thread: Building up a 3800... how much did it cost??

I thinking about building up a 3800 soon, not sure yet if i'll assemble the bottom end myself or not, most likely probably not. For the bottom end I plan on using 9.5:1 Diamond forged pistons uncoated, L67 rods (since i've seen way more L32 failures than L67), a new crank (again, seen alot of failures from turning these), ARP hardware most likely and thats all I can think of at the moment. Not sure if I should go with Clevite bearings or stick with stock, not sure on a cam either.

Whats your setup? What did it cost you? And no, i'm not interested in a junkyard short block. I'd rather build something potentially stronger than stock.

...why? the stock bottom end holds up to pretty much anything you throw at it. i dont see a need to build.

Originally Posted by Iron Indian

I thinking about building up a 3800 soon, not sure yet if i'll assemble the bottom end myself or not, most likely probably not. For the bottom end I plan on using 9.5:1 Diamond forged pistons uncoated, L67 rods (since i've seen way more L32 failures than L67), a new crank (again, seen alot of failures from turning these), ARP hardware most likely and thats all I can think of at the moment. Not sure if I should go with Clevite bearings or stick with stock, not sure on a cam either.

Whats your setup? What did it cost you? And no, i'm not interested in a junkyard short block. I'd rather build something potentially stronger than stock.

Shawn - you probably already know all of this, but just get an L36 shorty - you can get them for ~$250 all day long.

Tank it and polish the crank - ~$125-ish
Deck it - ~$75-ish
Resurface heads - ~$60-ish
Valve job - new seals - ~$150-ish
Clevite bearings (yes ) - ~$22
Main bolts (I wouldn't mess with studs - because if you do, then you "should" get it align-bored, too.) I would use studs for the heads, though - and I did.
Mains - ~$50
Head studs - $80
Rod bolts - ~$100
All new gaskets/seals, etc - ~$170-ish (full gasket set from ZZP is $160)
Cam - gray area here - VS or XP is tried and true, but it's all about preference. ~$320
Diamond 9.5:1's - ~$700-$900

I've already decided that my next GP will be turbo.

-Swash

May i suggest steering away from the diamond pistons.

They have a short skirt on them and after a few miles they will be nice and broke in, causing your car to sound like a diesel.

Plenty of aftermarket pistons out there that would be a better investment.

Originally Posted by Merlin

They have a short skirt on them and after a few miles they will be nice and broke in, causing your car to sound like a diesel.

This is sometimes true - but not always. Certainly a good point to consider. I know in LSx applications - and other SBC instances as well - they come with an offset pin - specifically to address the noise issue. I know of 1 GP owner with diamond pistons - and he has (at least) several thousand miles and numerous track passes on them - no piston slap.


-Swash

I know of a wbody owner and a 3.8l f body owner that have the worst piston slap i have ever heard.

They are hit and miss. I would spend 200 more and not take the gamble.

Originally Posted by Bio248

...why? the stock bottom end holds up to pretty much anything you throw at it. i dont see a need to build.

L67s and L36s are far from bulletproof. I'd rather build something personally. Too many people are scaried to build these motors and I don't know why. I don't want the cheap way out.

I'd rather build a good solid foundation that last for years, instead of replacing short blocks every season (like some people tend to do). Thats my opinion...

Originally Posted by Swash

Shawn - you probably already know all of this, but just get an L36 shorty - you can get them for ~$250 all day long.

Tank it and polish the crank - ~$125-ish
Deck it - ~$75-ish
Resurface heads - ~$60-ish
Valve job - new seals - ~$150-ish
Clevite bearings (yes ) - ~$22
Main bolts (I wouldn't mess with studs - because if you do, then you "should" get it align-bored, too.) I would use studs for the heads, though - and I did.
Mains - ~$50
Head studs - $80
Rod bolts - ~$100
All new gaskets/seals, etc - ~$170-ish (full gasket set from ZZP is $160)
Cam - gray area here - VS or XP is tried and true, but it's all about preference. ~$320
Diamond 9.5:1's - ~$700-$900

I've already decided that my next GP will be turbo.

-Swash

Good info, thanks....

Originally Posted by Swash

This is sometimes true - but not always. Certainly a good point to consider. I know in LSx applications - and other SBC instances as well - they come with an offset pin - specifically to address the noise issue. I know of 1 GP owner with diamond pistons - and he has (at least) several thousand miles and numerous track passes on them - no piston slap.


-Swash

Good info, i'll keep that in mind if I go with forged Diamonds. I've also heard with the diamonds, don't go with the coated version. Something to do with tolerence? I donno I just heard uncoated was the way to go with diamonds.....

bump ( so i can subscribe and be updated on this thread )

Originally Posted by QwikGT

i run an L32 now because of the coated pistons and powdered rods. brand new GM
timing set, new rings bearings, etc. there are no reliable timing sets so i didnt go cam and kept my roller rockers. ive said it before, the tune is the most important piece to these cars. a crappy tune will break rods and destroy diamond pistons in no time. my build cost me 500 for the shortblock, 300 for the remaned heads, 1200 to rebuild it and put it all together

Tuning is definatly the key with any build. So many learn the hard way though. I want the Diamonds for extra durability. They are without a doubt stonger than stock L67/L32.

You right about the timing sets, with all the problems out there i've honestly thought about just sticking with rockers for realibilty.