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Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Aug 13, 2021 8:59 am
by split1950
When I looked closely at my CB performance pressure HAT bases, I saw they are far from flat, there was not decent way of solving it so thanks to the magic of CAD and CNC I have an alternative, fresh back from the anodiser today
IMG-20210810-WA0001.jpg
I decided to put an O ring between the base and TB, not sure what CB intended but if I can avoid a crappy gasket I will.
I hope they work......
First I have to solve my gear linkage issue. The split bug has some cross braces inside the tunnel which stops me from running it along the bottom like I could on my later chassis I used on my last car (bug@5speed shifter), so I have some nice needle bearing UJs to make a Z link, and I mounted a shift rod guide the same as VW used at the front in the back, hopefully by the end of Sunday I'll have it done, but so far access inside the tunnel has been tricky to say the least, let's see. I refuse to cut holes in the tunnel unless there is absolutely no other way.
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Aug 13, 2021 11:12 am
by Steve Arndt
You could probably sell those on samba. Worth posting an add and checking interest.
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Tue Aug 17, 2021 9:03 am
by split1950
Exhaust system purge welded and 100% finished up to the turbo. Still need to decide on a silencer solution (later).
IMG-20210816-WA0006.jpeg
Also, my tinwares are finished too.
IMG-20210816-WA0001.jpg
If I can solve my shift rod Z link I'm gonna be happy!
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Tue Aug 17, 2021 9:13 am
by rubenski
That exhaust looks killer!
Verstuurd vanaf mijn SM-A515F met Tapatalk
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Tue Aug 17, 2021 1:45 pm
by Wally
split1950 wrote: ↑Tue Aug 17, 2021 9:03 am
Exhaust system purge welded and 100% finished up to the turbo.
Nice job!
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Tue Aug 17, 2021 2:23 pm
by madmike
nice work , you should be proud

Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Tue Aug 17, 2021 11:56 pm
by split1950
There's some hours in it for sure, and cutting stainless is a pain, but I am really happy with the result. I think the CAD mock up / model really made it easier to figure out. I can't wait to hear it used in anger!
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Dec 10, 2021 7:03 am
by split1950
Finally got around to fixing the small oil leak on the crankcase joins.....I previously used Permatex but after only an hour of cam break in / bench running it seemed to almost drip out in one spot, causing a "weep" enough to drip once a fortnight. Not good for my OCD.
I saw Jake (Raby) talking about RTVs so I've split it and sealed the case halves with "Renozil" +300C RTV and some Curil T for the cylinders to case.
I also swapped out my OE case through bolts for some 10mm CSP Chromoly type 1 head studs allowing me to torque up to 30 ft/lb.
Taking a look inside the cam break in had worked well so there's another positive of all this.
I had never been happy with the head to inlet manifold mating surface after the inlet porting (the width was thin) so welded
IMG-20211127-WA0005.jpeg
and got my buddy Steve to resurface them like this
IMG-20211203-WA0000.jpg
I obviously stripped and cleaned them after this, will finish assembling the top end tomorrow with new copper sealing rings.
Should get a good seal under boost now!
Hopefully soon I'll get my 915 trans back with the Quaife ATB / LSD
20211111_144326.jpg
Then there's these.....spot the difference?
IMG-20211007-WA0004.jpg
IMG-20211007-WA0000.jpg
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Dec 10, 2021 9:50 am
by Wally
split1950 wrote: ↑Fri Dec 10, 2021 7:03 am
.... allowing me to torque up to 30 ft/lb.
I would be extremely carefull with that.. Original is 25 ft/lb and more torque could lead to (too) smal(ler) bearing gaps with all possible problems originating from that.
Better studs doesn't need to be torqued higher, just because you could imho. I use better studs just for more stability, but torque them to original specs.
Just my 2 cents of course.
Very nice machining!
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Dec 10, 2021 11:38 am
by split1950
Hmmmm yes I do see your point Walter, no going back now I don't want to disturb the sealant.
The info came from Stateside I was careful not to exceed 30 as I was a bit cautious but JC knows his stuff so ......
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Dec 10, 2021 12:00 pm
by Wally
split1950 wrote: ↑Fri Dec 10, 2021 11:38 am
Hmmmm yes I do see your point Walter, no going back now I don't want to disturb the sealant.
The info came from Stateside I was careful not to exceed 30 as I was a bit cautious but JC knows his stuff so ......
First time I bought my ARP through bolts from LN, they said to torque to 36 # and came back from that later after I also experienced too tight and all consequences from it..
Its always confusing if you ask same question to several different tuners, you get same number of different answers haha! I hear you.
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Fri Dec 10, 2021 12:09 pm
by split1950
Yeah lol it's really hard to know what to do.
Hopefully I'll be ok as I said I'm no more than 30 which is plus 20 percent from stock.......
It rotated freely but obviously cold.
I do appreciate your comments though as you've proven your knowledge plenty!
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Sun Dec 12, 2021 12:44 am
by Eddie010
Did you use casesavers for those 10mm studs, and if so which ones.
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Mon Dec 13, 2021 8:44 am
by split1950
Eddie010 wrote: ↑Sun Dec 12, 2021 12:44 am
Did you use casesavers for those 10mm studs, and if so which ones.
I used the 10mm type 1 studs as through bolts to replace the 6 standard one's as an alternative to ARP case through bolts (I couldn't get any in the UK without paying £200 shipping and waiting for weeks).
Please note if you go down that road there is discussion if you should increase from the 25 ft/lb of torque or not. I went to 28~30ft/lb on the advice of a builder here, if I had to do it again I wouldn't go over 28, but I'll let you folks know if I run into any trouble or not later as a result of going higher.
For the heads studs themselves I used ARP type 4 head studs, they went straight into the case same as the OE versions.
Re: 2270cc type 4 EFI Turbo: my first engine build
Posted: Mon Dec 13, 2021 10:25 pm
by Eddie010
split1950 wrote: ↑Mon Dec 13, 2021 8:44 am
Eddie010 wrote: ↑Sun Dec 12, 2021 12:44 am
Did you use casesavers for those 10mm studs, and if so which ones.
I used the 10mm type 1 studs as through bolts to replace the 6 standard one's as an alternative to ARP case through bolts (I couldn't get any in the UK without paying £200 shipping and waiting for weeks).
Please note if you go down that road there is discussion if you should increase from the 25 ft/lb of torque or not. I went to 28~30ft/lb on the advice of a builder here, if I had to do it again I wouldn't go over 28, but I'll let you folks know if I run into any trouble or not later as a result of going higher.
For the heads studs themselves I used ARP type 4 head studs, they went straight into the case same as the OE versions.
Sorry my bad, I thought you were talking about head studs.