Author Topic: 11mm block for performance build? (Read 7135 times)

truckinwagen · « **on:** April 06, 2009, 01:56:32 pm »

I am working on a couple performance built motors, but only have the early blocks with 11mm head bolts, I am wondering if 11mm studs would be able to hold lots of HP and boost.

I dont want to have to try and find new blocks, should I even worry about it, just run 11mm ARP studs, or should I have the blocks tapped for 12mm studs?(of which I have set)

I am planning on supercharging one motor with a G60 and turboing the other with my K24 to compare power output, driving characteristics etc... looking for 150+HP from each build

what do you guys think about running 11mm studs on such builds?

-Owen

RabbitJockey · « **Reply #1 on:** April 06, 2009, 02:21:34 pm »

i don't know what all is actually different on the blocks but i think the 12mm bolts actually go much deeper, i don't know if you can just drill out an 11mm block. i don't think you will see 150hp with a k24, i even question if a g-ladder could do that i know they make alot more than that on a g60, but i think it takes alot more flow to make similar power in a diesel, like a guy in canada put a k24 on an aba and was making over 200whp but really i have no idea. we'll see though. i'm excited to see how the supercharging goes.

jtanguay · « **Reply #2 on:** April 06, 2009, 05:01:15 pm »

the 11mm studs will thread deeper into the block, so they aren't an option, but rather a necessity.

run that supercharger with a really slim pulley and hold on!!! :twisted: but really i think you want to take advantage of flow and equalizing pressure in the engine. having it breathe better will definitely let the supercharger do its job. lots of good porting/polishing!

Turbinepowered · « **Reply #3 on:** April 06, 2009, 05:42:32 pm »

Quote from: "jtanguay"

the 11mm studs will thread deeper into the block, so they aren't an option, but rather a necessity.

run that supercharger with a really slim pulley and hold on!!! :twisted: but really i think you want to take advantage of flow and equalizing pressure in the engine. having it breathe better will definitely let the supercharger do its job. lots of good porting/polishing!

In line with that, might I suggest something other than the stock TD air intake? If not something fancy like an all up dual plenum job, at least a good well ported gasser intake.

truckinwagen · « **Reply #4 on:** April 06, 2009, 06:54:11 pm »

I am currently running a ported gasser intake which will go on one of the new motors, and I will either get another one or modify an NA diesel manifold to work.

I am confident that I can get the HP numbers I want with the mods I have planned, A very aggressive port and polish of both motors, WM injection, 1.9 pistons with a sleeved block etc...

my question is will the 11mm studs hold the head down well enough with high boost or would it be necessary to go with 12mm ones?

it shouldn't be too hard to get the blocks tapped for 12mm studs, even if it means helicoiling it, but I just wanted to know if it would be worth the bother.

-Owen

jtanguay · « **Reply #5 on:** April 06, 2009, 06:59:00 pm »

Quote from: "truckinwagen"

I am currently running a ported gasser intake which will go on one of the new motors, and I will either get another one or modify an NA diesel manifold to work.

I am confident that I can get the HP numbers I want with the mods I have planned, A very aggressive port and polish of both motors, WM injection, 1.9 pistons with a sleeved block etc...

my question is will the 11mm studs hold the head down well enough with high boost or would it be necessary to go with 12mm ones?

it shouldn't be too hard to get the blocks tapped for 12mm studs, even if it means helicoiling it, but I just wanted to know if it would be worth the bother.

-Owen

andy2 was having head sealing issues.. its not exactly the studs that are the sealing problem, but the fact that the aluminum actually distorts with the super high cylinder pressures. i think he even tried 14mm studs with the same result

. 12mm studs couldn't hurt, but i can't see how 11mm studs would be a problem, unless they don't thread in as deep.

truckinwagen · « **Reply #6 on:** April 06, 2009, 07:01:36 pm »

I will check how deep the threaded bosses in the block are.

does anyone know how deep the 12mm bosses are? for comparison?

saurkraut · « **Reply #7 on:** April 07, 2009, 06:33:16 am »

The thread bosses in the 1.5 block are very deep. That is not the problem.

From my experience, the concern would be if any 1.5 block that has had a head already installed is still good. They all may be damaged from the intial head installation. The stock bolts a way too short.

It is possible that you could do everything right, studs and all, and still end up with a cracked block.

If your really intent on makeing a forced induction 1.5, get a 12mm 1.6 block and put your 1.5 stuff in it. I also know of a bone stock, brand new, 1.5 short block that is available if you want to go that route, but it won't be dirt cheep.

truckinwagen · « **Reply #8 on:** April 07, 2009, 08:03:08 am »

the thing is that I got my hands on two 11mm 1.6L blocks as well as a 1.5

Getting another block in any configuration is a real pain in the ass up here, everyone thinks that 80's vw parts are made out of gold.

I will have the blocks checked for cracks before I bore them to be sure I am safe then.

-Owen

MJF · « **Reply #9 on:** April 07, 2009, 08:16:26 am »

Quote from: "truckinwagen"

I am currently running a ported gasser intake which will go on one of the new motors, and I will either get another one or modify an NA diesel manifold to work.

I am confident that I can get the HP numbers I want with the mods I have planned, A very aggressive port and polish of both motors, WM injection, 1.9 pistons with a sleeved block etc...

No comments of bolts, but inner mods are mostly waste of money if you are after only 150hp. You probably will get 150hp from 1,6 K24, but thats about it, no more.

truckinwagen · « **Reply #10 on:** April 07, 2009, 08:19:05 am »

well the 150HP mark is just a starting place for the motors, eventually I want to twincharge one of the motors, but I want to try the turbo and superchargers separately first to see how they act before putting them together.

arb · « **Reply #11 on:** April 07, 2009, 09:09:45 am »

Superchargers are sexy and have been in our hands longer than turbos... but there is a HP price to pay with them. 10% - 20% of your crank HP will be devoured by the supercharger. That's why turbos have become so popular - they get their hp from the wasted energy going out the exhaust.

And the type of supercharger also affects this - Roots, centrifugal, or twin-screw "

Here's a comparison : http://www.ststurbo.com/turbo_vs__supercharger

and details about 2 of the 3 types of supercharger
http://www.kennebell.net/techinfo/general-info/twinscrew-vs-roots-fromcatalog.pdf

saurkraut · « **Reply #12 on:** April 07, 2009, 10:53:06 am »

Quote from: truckinwagen

the thing is that I got my hands on two 11mm 1.6L blocks as well as a 1.5

Getting another block in any configuration is a real pain in the ass up here, everyone thinks that 80's vw parts are made out of gold.

I will have the blocks checked for cracks before I bore them to be sure I am safe then.

-Owen

A visual inspection is not enough. See if you can get a dye penatrant test of all of the 11mm holes befor you put any money into an 11mm block. And still i think your taking a big chance.

I got burned by 11mm fasteners on turboing a 1.5 a couple of years ago.

http://www.vwdiesel.net/forum/index.php?topic=11786.0

If your not in too much of a hurry, I'll sell you my 11mm raceware studs when i take the motor down. But I'm done with 11mm blocks. I seriuosly concidered that brand new 1.5 short block, but now I don't think I'd touch a 11mm block with a ten foot pole. I'll resurect the 1.5TD with a 1.6TD block, 1.5 crank, maybe 1.9 rods, and 1.6td pistons with a little shaved off of the crown.

truckinwagen · « **Reply #13 on:** April 07, 2009, 12:45:11 pm »

the supercharger I am using is a VW G60 scroll compressor, very efficient and makes lots of boost quick, they are a little fragile, but with regular maintenance and care they can be great superchargers

I will have a shop do a dye test on the blocks before I put any money into them, I really would like to get some 12mm blocks, but there are none anywhere near for less than a premium for junk.

as for the racewares, how do they compare to ARP?
I might be interested in grabbing those from you when you pull your engine apart.

jtanguay · « **Reply #14 on:** April 07, 2009, 03:19:15 pm »

Quote from: "truckinwagen"

the supercharger I am using is a VW G60 scroll compressor, very efficient and makes lots of boost quick, they are a little fragile, but with regular maintenance and care they can be great superchargers

I will have a shop do a dye test on the blocks before I put any money into them, I really would like to get some 12mm blocks, but there are none anywhere near for less than a premium for junk.

as for the racewares, how do they compare to ARP?
I might be interested in grabbing those from you when you pull your engine apart.

well personal experience from racewares is that they are junk. at least when using an MLS gasket anyways (they need extra torquing to 'crush') and mine broke while andy2 was torquing it

get the block magnafluxed if you can. even if it is cracked you could probaby do that stitching or something.

Author Topic: 11mm block for performance build? (Read 7135 times)

arb