109 block question.

[SS_Sean]

I appologize, but I'm rather new to this whole TB thing. I hear '109 block' thrown around a lot. Was this the stock block for the 86-87 TB's? It's my understanding it's a pretty strong unit (obviously - guys in the 9's with it). Were the stock rods, pistons and crank forged, and that's why it's desireable?

 

[Dominic]

109 is what all 86 87 turbo regals came with from the factory,it's the last 3 numbers in the casting # on the block, the crank and rods are cast. The pistons are hepalites (sp?) Stage 1 and Stage 2 are the better blocks. There are goods and bads to the stock blocks but they can hang in there pretty damn well if they are set up properly.

BTW:

Nice Malibu in your sig :biggrin:

 

[Boost231]

the 109 has been in the 8's and all 84-87 TR came with them

 

[SS_Sean]

Thanks. The malibu is great to race and fun to drive on the street!!

Cast crank and rods, though, huh? That doesn't sound too appealing. What's with this hepalite thing? Sounds like a new vacuum cleaner filter. :biggrin:

 

[marred4life]

the 109 has been in the 8's and all 84-87 TR came with them

true but the 84-85 109 blocks are weaker at the valley(lifter area) the 86-87 blocks is alot stronger at the lifter area

 

[Boost231]

true but thats not going to effect hp. there are some other differences as well but its still a 109

 

[SS_Sean]

So what's the story on the crank, rods and pistons?

 

[Jerryl]

A 109 block (as stated) is an indication of the last 3 numbers of the casting.
I am pretty sure that all 109 blocks are 20 bolt blocks.

84-85 are typically not 109 blocks but rather 329's or commonly referred to as "14 bolt block". These do not have the turbo oil return drain drilled in the front of the block. Sometime mid 85, some cars got the 20 bolt blocks as well.

There have been 10 sec 14 bolt blocks, so, while the 20 bolt blocks are stated to be stronger, the 14 bolt block has not been proven to be "weaker".

At the bottom of the link are some pics of the blocks.
Block Photo Guide

 

[SS_Sean]

Thanks...found more info here:

Index to Photo Guides

 

[NUTS4LC2]

So what's the story on the crank, rods and pistons?

The crank is 229 if not mistaken (can't remember), the rods are 3 dots, pistons are crap & hence 1st thing most guys replace when HP is intended & the heads are 8445. HTH.

 

[waddell87]

whats the difference between on centre and off centre blocks, would 109 stocks be classified as an on centre block? thanks

ya very nice launch in the malibu

 

[Jerryl]

Strength question

Just in case you missed this ............
http://www.turbobuick.com/forums/ge...53511-14-bolt-hot-air-block-will-hold-up.html

 

[49-blues]

6109s are all off center blocks-only stage2 0153 are on centers.

 

[Turbo1dr]

So what's the story on the crank, rods and pistons?

I can tell you're a Chevy guy....lol....worring about cranks, rods and pistons! When the GN starts to out run your Malibu then it's time to start "thinking" about upgrading the stock rods, crank and pistons. Even 125mph isn't too awful hard on the stock stuff....if you don't detonate it. Guys have gone 138mph on stock internals. Look up "bird" on here. He's gone super fast on stock stuff....just don't ask for how long.

 

[KevinB]

No, the stock stuff was not forged. My old one (100% stock) lasted to 11.1. I added a little detonation to it at that speed and melted a piston.

In the past year or so it's become alot more affordable to make a "109" last. Thanks to "Chinese" parts

If you are going to rebuild your stock block, you might as well buy the Chinese forged crank and forged rods. They do not cost that much more than having your stock stuff reconditioned. Another must imho is having an experienced Buick V6 builder take care of your build up. Attention to detail is the key.

My "109" block has many low 10 second and high 9 second passes on it. It contains an Eagle crank, K1 rods, forged pistons and girdle. So far it's doing great! My confidence in it is VERY high:biggrin: It's been way more reliable than my buddy's BBC running almost the same numbers (but slower:tongue:.) He's got good rods, crank, pistons in his, but has had bad luck keeping it together.

 

[Turbo1dr]

Look up "bird" on here.

Or look up KevinB...

 

[KevinB]

Or look up KevinB...

Thanks! Here's a list of about 40 or so stock block 9 second cars.
TSM leader board times - t6p.com - Turbo Buick Regal Resource


BTW, I'm near the bottom:tongue: There is a lot of people faster than me

 

[SS_Sean]

So that guy that ran an 8 did it on a stock short block???

 

[vader87]

It was with a 109 block but it wasn't stock.