Yes, More Mk2. (VW, Aaron!)

So, I'm actually getting pretty close to go-time. A recent, 4 hr ride up to a friend to get cage work done made me realize I have some pretty important questions, ones that I have no idea how to answer.

My car has the VW ABA 2.0 block, but with an earlier 1.8 head on it. Where should I assume the 'redline' is at? Revs are limited by valvetrain, right? So the normal 1.8 limit?

I've had it to 5,500 or so, but its still pulling plenty hard there and I don't want to hurt anything...

Next question- what is the normal op temp for a motor like that?
the car was getting warm in traffic on the Washington bridge, and that's about when I noticed I have no idea where 'too hot' was.

---

Enablers, All of you.



Edited 1 time(s). Last edit at 04/01/2015 09:23AM by BobOfTheFuture.

Revs are usually limited by valve float and if the head had hydraulic lifters. Once those get sorted, the next limiting factor is Mean Piston Speed (MPS). This is all about stroke and rpm, but it doesn't take into account the weight of everything moving up and down. 18-22m/s is a generally safe area for stock engines.

So without knowing what cam, springs, and lifters you have.... it's hard to make an educated guess. Generally, I think, hydraulic 8vs are in the 6500-7000 range. Solid lifters are in the 8k range.

As fas as temps go, 230F is generally the high end of operating temperatures for most gas engines. My 16v doesn't get over 210 on a racetrack though.
Oil pressure is the real killer on any old engine. Make sure you at least have something at idle when hot.

I came here expecting this:


I am dissapoint.

---

KF7RWG
http://www.utahrallygroup.com

What Mr. Culbertson said... with a little head and bottom end work you can spin em up much higher.

A side note.. those motors are tough little buggers... ever see a tacho go around and back up to the 3krpm reading? Neither did I till it let me hit 1st on a down shift when I was aiming for 3rd...

Took a few tries to start.. but eventually she did and ran for another 20k of a wanna be a rally driver at 16 years old abuse.

Quote
DexterVW
What Mr. Culbertson said... with a little head and bottom end work you can spin em up much higher.

A side note.. those motors are tough little buggers... ever see a tacho go around and back up to the 3krpm reading? Neither did I till it let me hit 1st on a down shift when I was aiming for 3rd...

Took a few tries to start.. but eventually she did and ran for another 20k of a wanna be a rally driver at 16 years old abuse.

Picked up a $50 mk2 golf with a 1.8 8v. Drove the absolute piss out of that car on backroads in the woods and farmlands near where I grew up. It had less than 5psi of oil pressure until 2500rpm. Our solution was to always have it pinned, and it worked great until it didn't a few years later

Quote
BobOfTheFuture
My car has the VW ABA 2.0 block, but with an earlier 1.8 head on it. Where should I assume the 'redline' is at? Revs are limited by valvetrain, right? So the normal 1.8 limit?

Which 1.8 head?

Stock, the 16v 1.8 heads have a 7200 rpm rev limit and the oil temp sender is in the head about as far as possible from the inlet side, so it reads hot. I've seen temps over 310 on the EFA on long slow hard climbs, but usually it's somewhat lower. The operating manuals basically said "don't worry about it unless it's over 325".

Stock, the 8v 1.8 heads have a 6500 rpm rev limit. The oil temps shown by the EFA are much more normal. Should be around 180-190 when idling, and in the low 200s when pulling.


You can make them all spin up faster with some valve spring work, but you'll find the motors fall off the cam well before the current redline anyway. By that I mean the cams aren't designed to run that fast so they don't hold the valves open correctly for those RPMs and you start losing power. To correct that you'll either need a new cam designed to run at the higher RPMs or an adjustable cam wheel to turn your current cam (at the loss of low end power). And that's before you get into the whole hydro vs non-hydro tappet thing.

The motors are pretty tough. I've gotten one hot enough that it dieseled and kept running by itself after the ignition was cut. We let it cool down, reconnected the water hose, filled it from other competitors' water bottles, and off we went. Ran 7 more races on that motor and still have it in storage somewhere.

---

Self-righteous douche canoe

What fuelling or management is the car running?
Being an 8v, it would need to be a pretty fruity engine spec for the bottom end internals to become a concern. They are tough engines.

For info the "tall block" 2.0 engines have an 82.5mm bore and 92.8mm stroke and a rod length of 159mm (21mm pin) if you wish to work out piston speed.
The "short block 2.0 has the same bore and stroke but uses a 144mm rod length (20mm pin).

---

Disappointingly not yet a Jackass

Quote
hoche

Stock, the 16v 1.8 heads have a 7200 rpm rev limit and the oil temp sender is in the head about as far as possible from the inlet side, so it reads hot. I've seen temps over 310 on the EFA on long slow hard climbs, but usually it's somewhat lower. The operating manuals basically said "don't worry about it unless it's over 325".

Yah, on our 16v we see 300+ degrees f on every stage because the sensor is right over the #4 exhaust port. Never had any issues even at 350f but it makes people excited to look at the gauge! Water temp never budges from 180f.

---

____________________________________________________________-

One. Class -- 2WD

www.quantumrallysport.com

http://www.facebook.com/home.php?#/pages/Quantum-Rally-Sport/281129179600?ref=nf

Quote
danster
What fuelling or management is the car running?
Being an 8v, it would need to be a pretty fruity engine spec for the bottom end internals to become a concern. They are tough engines.

For info the "tall block" 2.0 engines have an 82.5mm bore and 92.8mm stroke and a rod length of 159mm (21mm pin) if you wish to work out piston speed.
The "short block 2.0 has the same bore and stroke but uses a 144mm rod length (20mm pin).

I can see why they made the tall block...nice numbers..
Wonder if that block ever made it to Fortress Amerikuh™?

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

The "tall block" is the ABA block the OP was talking about. It was an 8v crossflow head and was the standard 2.0 engine in the Mk3's.

There was also a 16v variant, the ABF, which didn't make it here. You can sorta make one by taking an earlier 16v head and slapping it on an ABA block though. You have to block off some oil ports and find the right manifolds and dick around with the ECU and so on. Nothing major. Or just import one from Europe.

---

Self-righteous douche canoe

Hoche, the OP has Hollingsworth's old car. You probably know what head is on that thing?!?!?

---

rally gods would turn in their graves if they ever knew Lada's were now part of EU rallying!!!

Oh!

That's an 8v CIS head on an ABA block. It's got hydraulic lifters and a mild cam, probably something like a 268. It's a good strong motor though - plenty enough to make that car scoot, especially if you're just starting out.

Craig would occasionally run it up and hit the rev-limiter while rallycrossing, so I wouldn't worry about that aspect of it too much.

---

Self-righteous douche canoe



Edited 2 time(s). Last edit at 03/31/2015 09:10PM by hoche.

For your collective amusement, this is from the 1985 GTI Owner's Manual (8v):




I thought I had one from an '88 16v, but I can't find it.

---

Self-righteous douche canoe

Quote
hoche
For your collective amusement, this is from the 1985 GTI Owner's Manual (8v):




I thought I had one from an '88 16v, but I can't find it.

---

John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

Quote
hoche
The "tall block" is the ABA block the OP was talking about. It was an 8v crossflow head and was the standard 2.0 engine in the Mk3's.

There was also a 16v variant, the ABF, which didn't make it here. You can sorta make one by taking an earlier 16v head and slapping it on an ABA block though. You have to block off some oil ports and find the right manifolds and dick around with the ECU and so on. Nothing major. Or just import one from Europe.

The 16v head should fit an ABA block without issue. One headgasket locating dowel may need tweaked.
Obviously one still needs various other components such as pistons, IM shaft, oil pump with drive gear and dizzy blank, and timing belt gears swapped to build an ABF clone but it is fairly simple.

Oil port modifications sounds like an issue when using the later 06X type block, or when fitting the 8v crossflow head to an early block which does not have the extra area cast in at the front to seal the oil drain between cylinders 1 and 2.

---

Disappointingly not yet a Jackass