Topline head and ARP stud observations

[DanHoug]

well, i think my car is fixed and back in business. in the course of the repair (see end of New head, still blowing coolant thread), i installed a new Topline hydraulic head. here's what i see:

- head had everything in the right place. needed to transfer my idler pulley and coolant studs but that was it. i swapped out the existing VC studs for the shoulderless ones used with the rubber gasket.

- the injector wells are a bit tighter than the OEM German head. i had to grind down the outside diameter of my 27mm socket in order for it to fit on the injectors.

- port edges of the swirl chambers were a bit rough.. i thought about touching them up but didn't. figured the tough environment would smooth them out shortly.

- threads on both the injectors and the GPs seemed well formed and cut with unworn dies.

- i picked up .5-1.0 bar hot oil pressure just simply replacing the head.

- just buy a machinist straight edge. if you are pulling a head for any reason, you should check the head and block. the new head was dead flat. my old head with 320K miles was warped about .0015 or less.

- having tasted the beauty of ARP studs, no VW diesel head of mine will ever go back on without studs. pull the head 4 times and the studs are almost paid for. the certainty of the torque process paid for them the first use anyway. this new head has been off twice now and i should've had the studs from the first time on. get PN 204-4706 for 12mm studs made for VW diesel.

-dan

[Vincent Waldon]

Great post Dan... thanks for taking the time to share your observations. So often in our hurry to move on to the next "problem" we forget to report back on our learnings... yet there's huge value for the rest of the board in these kinds of posts!!!

[DanHoug]

this board has been extremely helpful and it only makes sense to contribute what i can...

and there was one other important thing i forgot about the Topline. there was a casting ridge just below the cam sprocket that protruded enough to cause the metal dust shield to stick out and rub on the idler pulley. i had to grind off the ridge so the tin could lay flat. if you have a new head with this ridge, just whack it off with a file or grinder before putting the head in place. it was sprue only about 1/8" wide and came off easily.

-dan

[vwtyp133]

Any indication of where Topline had the head cast or the machining done?

J.R.
SoCal

[DanHoug]

Raphaela, Argentina? not sure from the website..

http://www.toplineauto.com/about-us.asp

-dan

[Nevadan]

- having tasted the beauty of ARP studs, no VW diesel head of mine will ever go back on without studs. pull the head 4 times and the studs are almost paid for. the certainty of the torque process paid for them the first use anyway. this new head has been off twice now and i should've had the studs from the first time on. get PN 204-4706 for 12mm studs made for VW diesel.
-dan

I have a question on the ARP studs.......On my 85 Jetta Turbo Diesel there's that tin protective cover that's bolted to the block that will prevent the head from sliding down on the block because the cam nose and belt adjuster pulley bolt stick out. Is there a way around this? Possibly unscrew the stud and bend/pry the tin so the cam nose can avoid contact. Has anyone done this with a TD? Am I over-thinking this?

[Nevadan]

Another ARP Head Stud Question

Per this link to Summit Racing's page for ARP's part number 204-4706:

http://www.summitracing.com/parts/ARP-204-4706/

there's 14 long studs 4 shorter and 16 short studs. Has anyone purchased this?

Why 14 head studs? What are the 4 shorter ones for? I can see that there would be 16 exhaust/intake studs. I need some clarification here?

[82vdub]

It's a generic picture of a stud kit.

I purchased this exact set for my headgasket project a couple weeks ago only to find I have an 11mm motor. I have this stud kit listed in the for sale area if anyone needs a set.