TMM 2332 FI Turbo Engine build thread

[miniman82]

Ebay is your friend.

[richie morena]

paul at vw speed shop can supply those exhaust parts www.vwspeedshop.co.uk

[Turbo_Manx_Maniac]

Update - Mostly been waiting on parts.

Recieved these offset rocker shafts from Autocraft.

When I spoke with them on the phone, we weren't sure of the shaft diameter and as it turns out these shafts were made for roller rockers and were too thin for the stock diameter SCAT rockers. They did look like they would do the trick if the rockers fit. Would have needed to add some oiling grooves if I used them.




After thinking about it for a while, I couldn't understand how I was the only one having issues with 1.25's. With nothing to use as a reference I decided to buy a set from CB and compare them.

So I ordered http://www.cbperformance.com/catalog.asp?ProductID=92


They are definately better, and ride on the valve where they are supposed to. Looks similar in the picture, but there is a big difference up close. Think I shot this pic before I shimmed the rocker pads properly. Probably make my pushrods too short now though.

SCAT




CB




Couple of differences:
CB uses 8mm swivels and SCAT uses 9mm, head looks to be the same size and the CB looks like it's made from chromolly.




Next, I scored on 1 5/8" thick flanges for the header. I was looking at Bugpack but they were $25 for 4, so I'd be at $50 for 8.
I got 8 of these for $2 ea, sweet!


So I'm sticking with swivels. Here's my reasoning, the ball in cup is supported very well and receives forced oil for lubrication. With an elephant foot, the shaft that holds the foot is small in diameter and recieves only splash oil. I've seen these wear, and heard of them breaking. I'd bet when used in a porsche they had additional oiling. Only bad things I've heard about swivels is they are harder to adjust and that's not an issue for me.


Gonna go wiff Nitro this weekend as NHRA is in town, no progress expected until next week.

[turbobaja]

[quote="Turbo_Manx_Maniac
[/quote]

I like those oil grooves in the shaft. I don't think mine came with those, but it seems like the best way to keep oil flowing out to the swivel foot .

Are those CB rockers 1.1:1? Maybe my eyes are playing tricks on me, but the P/R end of that CB rocker definately looks longer than that Scat rocker.

I've got an old set of Autocraft 1.25 rockers w/offset shafts too. I tried to swap shafts with my current build to correct the geometry, but I ran into the same problem you did . I never liked my Autocraft rocker setup, the pads always wore bad even with lash caps. I'm glad you're sticking with the swivel feet.

[Turbo_Manx_Maniac]

I like those oil grooves in the shaft. I don't think mine came with those, but it seems like the best way to keep oil flowing out to the swivel foot .

Are those CB rockers 1.1:1? Maybe my eyes are playing tricks on me, but the P/R end of that CB rocker definately looks longer than that Scat rocker.

I've got an old set of Autocraft 1.25 rockers w/offset shafts too. I tried to swap shafts with my current build to correct the geometry, but I ran into the same problem you did . I never liked my Autocraft rocker setup, the pads always wore bad even with lash caps. I'm glad you're sticking with the swivel feet.

Yeah they sure do look like 1.1's, I didn't put a dial indicator on them yet to verify but I will. I put them next to a 1.1 VW rocker and they are different.

Those Autocraft rockers need a spray rail, they wear bad if you use the stock oiling system. Not a big fan of roller rockers excpet for all out race, kind of like a serpentine belt for VW, fixes a problem that doesnt exist and creates new ones.

The groove in the shaft is really important, it's the only way oil can get from the pushrod to the rocker arm tip.

The SCAT rockers appear to be a higer quality rocker and are beefier, never used CB's rockers before so we'll see how it goes.

[Turbo_Manx_Maniac]

WOW!!!! Does anyone know of a place in the UK that can supply this kind of thing?

Cant wait to see how you plumb all this together!!!

Awesome stuff!!

J

Theres nothing magical about this pipe, it's just regular 14 or 16 ga mild steel. If you have access to a bender you can make this stuff yourself. Just buy a collector and flanges and fab away.

[Turbo_Manx_Maniac]

Time to finish up the valve train.

Fisrt let's make sure these CB rockers are really a 1.25.

Setup the dial indicator and take a reading.


Measured .480" lift. The SCAT rocker measured .495" lift on the same cam lobe, so the CB is slightly less than 1.25:1.

The cam lift is .397" measured.

CB = .480/.397 = 1.21:1.
SCAT was .495/.397 = 1.25:1.

The CB rocker does fix the issue I had with the swivel riding too high on the valve stem through the lift cycle, so I am going to use them.


The swivel foot has an oil hole drilled and receives oil from the pushrod through the rocker arm. This keeps it from running from just splash oil like an elephant foot.


Here's the oil passage through the rocker arm. One hole is the oil from the pushrod, and the other is the path to the rocker tip. Now you know why there is a spot of weld at the tip of rockers, it's to seal the drill hole through the rocker. There are grooves cut into the rocker arm shaft, the oil from the pushrod oils the rocker shaft, and is routed to the pushrod tip.


As I mentioned before, the SCAT setup uses a 9mm swivel, and CB uses an 8mm. The tips and ball size are the same, so no difference on contact patch with the valve stem.




Each rocker set has advantages over the other IMHO.
CB has a nicer endcap system, and I like the anti friction coating they put on all the parts. We'll see how they holdup over time. They also send you a great selection of shims to dial in the clearances.

SCAT rockers look to be a little beefier, have the 9mm hole so you can use a larger swivel or elephant foot. If I were using more lift >.500" I would have used a 9mm elephant foot and these rocker would work. You get less shims but they are a nicer shim.

On the CB rocker, looks to me that they have one forging and then drill differently for either a 1.1 or 1.25.




With both rocker sets, I was unable to prevent a rocker from riding on a mounting block. There was not enough space to put a shim between the rocker and block without binding things up. You should have 3-5 thousands side play on each rocker. I suppose it's fine to run with a rocker next to a stud block, however I usually grind the rocker block to provide the proper clearance. With the CB setup I was able to grind the blocks and set all of the side plays to ~.003-.004". I used a bench sander, you need to keep rotating the part to make sure it is ground perfectly flat. Take a little off and remeasure.



Works great to flatten exhaust flanges too.



Here's one side all happy. Valve train done.

[Turbo_Manx_Maniac]

Well the ball is rolling again.

Had fun with the car over the Thanksgiving weekend, that was the last trip on the little motor. It had an impressive showing, pulled 4 of us up Sand Dam repeatedly while the Subaru cars both failed to make it up until their 2nd or 3rd try.
This was a damn good motor, at higher boost settings this thing really makes some power. I did race a Suzuki 450 Quad on the street, I had 4 adults in my car and we stayed even until about 50 and then I started pulling away. I was amazed I could stay with a quad. I was at about 15 psi at that point, the close ratio tranny really makes all the difference though.

Today I pulled it out. Before doing so, I did a compression and leakdown test just to see how she was doing. This motor has been together for about 8-9 years if I remember, 99% off road.
Cyl #1 - 150 psi, 9% leakdown
Cyl #2 - 135 psi, 13% leakdown
Cyl #3 - 140 psi, 8% leakdown
Cyl #4 - 145 psi, 9% leakdown

Cylinder #2 was a bit low about a year ago when I checked, but it does not seam to be getting too much worse.

There is a forum member interested in the turbo and motor, we'll freshen it up and he'll get a great motor. Will be very interesting to see how the insides have faired over the years. It was built with good parts and very accurately balanced so I expect it will look VERY good inside.


Here she is ready to be taken apart and inspected.




Now that I had access to the T3 that was on the car (50 trim, .42/.48), I wanted to do a comparison to the hybrid going on the new motor.




Definately should flow more air.


Next was to take some of the parts off the old motor and prep them for the new motor.




I'm reusing the induction system, all the tin, Fan & alt, Dist, alt stand, etc.

I won't bother showing how to install these parts as it's very simple stuff.

Where I did run into an area requiring work is the tin.
This motor is about 3/4 - 1" wider than the old motor, and the aluminum case held the shroud up too high.





I had to trim the bottom edges of the shroud to get the proper height. I installed the alt stand and alt & fan to make sure everything aligned before trimming. Also, having the oil cooler in there helps make sure the height is right.

I had to cut the cylinder covers to make them properly reach the end of the shroud and accept the screw. I cut them with a cutoff wheel and rewelded them after hammering on them a bit to make them fit nice. I'll post some pics after they are painted.

Next steps will be to finish painting stuff. I have one small screw I have to helicoil on the intake manifold, and then install all the induction. Then it's exaust fab time and then we start her up for the first time. On the fast track now...


Was thinking about hammerite silver for the tin instead of the blue body color. What do you think?

[finseeker]

TMM, I want to thank you for this thread. I am in the process of rebuilding my turbo 2276 from an old mag case to the Auto Linea aluminum case. The main bearing oiling hole work you posted probably saved my build. First trip to Glamis with the new engine this weekend. Your thread has been a huge help.

[Turbo_Manx_Maniac]

TMM, I want to thank you for this thread. I am in the process of rebuilding my turbo 2276 from an old mag case to the Auto Linea aluminum case. The main bearing oiling hole work you posted probably saved my build. First trip to Glamis with the new engine this weekend. Your thread has been a huge help.

Awesome, glad it was of help!

Let us know how the new engine runs.

[turbobaja]

Glad to see some forward movement with the build TMM. Although I'm pretty dissapointed there's no killer looking header in the lates update yet .

With 8+ years of turbo off-road use on that 1835, you must have done something right. I'm curious what your feelings are about using a t-stat and flaps on these engines. I'm trying to decide if I need to make some overengineered contraption of my own to adapt to the scat shroud I've got or if I should just bypass the whole idea and save some time for once. I guess the tear-down will tell in more detail how the heat cycling treated those p/c's, but those compression and leakdown #s look very promising. What was the static comp on the old 1835, and what cam was in it??

[Turbo_Manx_Maniac]

Glad to see some forward movement with the build TMM. Although I'm pretty dissapointed there's no killer looking header in the lates update yet .

With 8+ years of turbo off-road use on that 1835, you must have done something right. I'm curious what your feelings are about using a t-stat and flaps on these engines. I'm trying to decide if I need to make some overengineered contraption of my own to adapt to the scat shroud I've got or if I should just bypass the whole idea and save some time for once. I guess the tear-down will tell in more detail how the heat cycling treated those p/c's, but those compression and leakdown #s look very promising. What was the static comp on the old 1835, and what cam was in it??

Hi TB, I'm the wrong guy to ask about cylinder tin, I run the absolute minimum. I have the under cylinder deflectors, top cylinder tin and shroud only. No thermostat, flaps etc. Remember a Manx has the engine flapping in the breeze, so I can get away with alot. I wouldn't follow my example in a baja, probably best to run a t-stat and flaps to make it last longer and heat up quicker and more evenly.

The 1835 ran 8.25:1, and had an Engle TCS10. It originally had a WEB 109 on 105LC and dual 40 Dells when I first built it. I can't wait to tear into it and see how some of the things I did to it effected the wear.

Stay tuned, the new motor will be running within 2 weeks.

[MarioVelotta]

Would you mind taking a pic of your oil temp sender in the filter and posting it? I think more people should do it that way. Patiently waiting for the header build also

[turbobaja]

...probably best to run a t-stat and flaps to make it last longer and heat up quicker and more evenly.

Stay tuned, the new motor will be running within 2 weeks.

Thanks for the good advice.....I was afraid you'd say that.

SWEET!

[fusername]

I always thought you need the flaps to direct the air, as they are part of VWs overall air flow design. maybe I am thinking of T4, and with the amount of work you must put into your builds, I doubt you would overlook something like that. I know no flaps in a T4=roasted engine soon enough, not sure how muchit affects T1.