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Brian_e  Samba Member

Joined: July 28, 2009 Posts: 4307 Location: Rapid City, South Dakota
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Posted: Thu Dec 11, 2025 10:07 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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| Murt wrote: |
Hi RickS
I’m using Scat |
Dave, you most likely have the 5/16" bolts, or the 3/8" bolts at most.
Double check the diameters on the next set before you do final assembly.
You are looking for thread diameter, not socket head size.
Brian _________________ So more or less the lazier and stupider you want to be, the nicer quality parts you need to buy.
-Modok
Narrowed beams, Drop adjustable spring plates, Bus disk brake and IRS kits.
www.type-emotorsports.com
Type E Engine Parts and Supplies
https://type-emotorsports.com/collections/engine-parts |
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Rob Combs Samba Member

Joined: December 30, 2020 Posts: 930 Location: South Bay LA, California
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Posted: Thu Dec 11, 2025 10:56 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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Hey Dave,
Brian is right on this one - mine torqued to 50. Recheck your Scat PN on the box against their website and you'll know exactly which bolt/rod combo you have.
Sorry OP, none of us meant to veer off but this is important to all of us! |
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RickS Samba Member
Joined: May 05, 2005 Posts: 653 Location: Speonk, NY
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Posted: Thu Dec 11, 2025 11:09 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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| Murt wrote: |
Hi RickS
I’m using Scat |
I don't believe Scat uses 7/16" bolts in any VW rod. I think you are headed for a rod bolt failure. I would find out what you have and buy new bolts, and torque them to the proper value. |
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Murt Samba Member

Joined: October 01, 2017 Posts: 689 Location: Kent, England
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Posted: Thu Dec 11, 2025 11:26 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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Interesting
Sorry dommer, I’ll follow this up over on my 2007cc build thread.
If I’ve effed up on the torque that I used on the instructions that came with the Scat rods, then it looks like I’ll be buying a new set of ARP2000’s when I eventually build the engine, and for the moment I’m just going to carry on with geometry
Dave _________________ 1966 VW Beetle ‘Jules’
1967 Kombi Splitscreen ‘Barney’
2018 VW Caddy Maxi R Line
2017 Golf GTD saloon
2008 VW EOS 2.0 TFSi |
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dommer Samba Member

Joined: December 19, 2007 Posts: 92 Location: Atlanta
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Posted: Yesterday 6:41 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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So it's been awhile since an update, and I guess this is now just my build thread, so sorry for the weird name.
When last I posted I'd just realized my issue with a borked bearing, which needed replacing. The new set of main bearings arrived and I've got the short block completed.
Before Christmas I went through the process of measuring all of the ring gaps in all 4 cylinders, weighing them for balance, finishing the fins a bit on the cylinders because they were a bit gunked up. I ended up spending several hours with hand files to do this only to realize a dremel would have done the work in a few minutes.
I then mounted and measured the deck height on each cylinder, and that revealed that all 4 of them were a bit too tall, which would have resulted in a pretty crappy and low compression ratio. I spent some time trying to find someone to machine them down for me. That took some time and $400.
The cylinders are now all machined to my specs and they're set up for 8.7:1 compression ratio, which I'm happy with. I mounted the heads, the tins for under the cylinders and the pushrod tubes, and tried to begin working on the rockers, but the studs were way too long, so I've got to cut those down a bit. I actually already cut them down, but was a bit too conservative and didn't remove enough material.
So now I've got the choice of either pulling the heads off to shorten the studs, or else doing the plastic bag and shaving cream/grease tricks to keep metal shavings from getting into my engine. I'm leaning toward the second as I'm a lazy man and I don't want to remove the heads for the third time. Am I stupid to consider shortening the studs while mounted to the motor?
Sexy pics for clicks:
Why won't the rocker assembly go all the way down?
Studs too damn long for the rockers.
Almost looks like a motor now.
Way too early picture of what the tin will potentially look like. |
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Cusser Samba Member

Joined: October 02, 2006 Posts: 33565 Location: Hot Arizona
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Murt Samba Member

Joined: October 01, 2017 Posts: 689 Location: Kent, England
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Posted: Yesterday 7:53 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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Hi @dommer
Good to see you back at it
Don’t be Lazy my friend, pull the heads, take off your studs and cut them properly away from your engine. _________________ 1966 VW Beetle ‘Jules’
1967 Kombi Splitscreen ‘Barney’
2018 VW Caddy Maxi R Line
2017 Golf GTD saloon
2008 VW EOS 2.0 TFSi |
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Brian_e  Samba Member

Joined: July 28, 2009 Posts: 4307 Location: Rapid City, South Dakota
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Posted: Yesterday 9:34 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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Another perfect example of why you never seal up ANYTHING until after you have done an entire mock-up of the engine. All the way out to the valve covers.
If you do the full mock-up, you don't have to worry about the mess, you just slip it back apart quick, cut them, and then continue on with your mock-up.
Only after you have ALL of your rocker geometry done, do you pull it all back apart for a final clean and then final assembly with sealer. Then you know the final assembly will go together nice and smooth with no surprises.
If the rockers don't go down all the way, spin the shaft 180deg. There is a slight counter bore on one side of the shaft to index on the lower end of the rocker studs.
Brian _________________ So more or less the lazier and stupider you want to be, the nicer quality parts you need to buy.
-Modok
Narrowed beams, Drop adjustable spring plates, Bus disk brake and IRS kits.
www.type-emotorsports.com
Type E Engine Parts and Supplies
https://type-emotorsports.com/collections/engine-parts |
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sled Samba Member

Joined: February 16, 2005 Posts: 6366
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Posted: Yesterday 9:41 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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| dommer wrote: |
| Am I stupid to consider shortening the studs while mounted to the motor? |
no, not stupid, but this needs to be done VERY carefully. I have actually done this once, and while I would definitely recommend Brians ^ methods, sometimes we need to improvise a little. First off I would use a pneumatic belt grinder. If you don't have one, go get one, they're an amazing tool. Then build a "bib" around each stud (maybe do this one at a time). Like take a paper shop towel and poke a small hole in it and push it over the end of the stud so everything else in the head is covered except the stud. Carefully grind (go slow). If the bib is a tight fit on the stud as it should be, zero grinding dust will be able to contaminate the rocker box (or anywhere else). If you go crazy grinding or cutting at full speed, sparks will get everywhere.
_________________ drive your split. |
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dommer Samba Member

Joined: December 19, 2007 Posts: 92 Location: Atlanta
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Posted: Today 6:16 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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| Murt wrote: |
Hi @dommer
Good to see you back at it
Don’t be Lazy my friend, pull the heads, take off your studs and cut them properly away from your engine. |
Damnit, I was afraid someone would say this. The dude I'm working on the engine is of the opinion that we just cover it with a trash bag, pushing the studs through the bag, cut the studs, and then remove the bag and blow it out once we're done with shop air. |
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Rob Combs Samba Member

Joined: December 30, 2020 Posts: 930 Location: South Bay LA, California
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Posted: Today 10:58 am Post subject: Re: Thinking of trying to build an engine for my type 3 |
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How tight are they in there?
Can you pull them one at a time, cut, and reinstall? Not sure if you have enough room to double-nut them or get a stud remover on them... |
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