2L 8V turbo shopping list

Cost feck all if you shave them down yourself with an alloy file.
You would lose no more swish than you would by installing a second head gasket.

To be fair though, as you know your engine has been built recently and is good the stacked gaskets will suffice. It was more a consideration for an unknown engine.

 

I trust the engine so will not over complicate things. If or when it blows up then Ill eat my words.

 

How would you know how much to remove to give a required Compression ratio?

 

CC check with a burette the existing clearance volume, do some calculations, and then remove metal to obtain the new desired volume.

 

I thought as much. Out of the skills scope for some then. Probably why the stacked gaskets will do.

 

It really is not that hard to do, even a decent syringe does the job. No harder than putting the right amount of sugar in one's coffee or toothpaste on the brush.
I wish they had used engine examples at school as it would have been far more interesting to learn the basic arithmetic and equations required to work it out.

It is good to use the grey matter occasionally and push what we can achieve.
Play around with an old engine and practice measuring volumes on that. In fact we still need an accurate clearance volumes for the various 16v engines. Have not seen it properly measure once on here. Head volumes, yes, but not a built engine. Be good to see if it matches the factory figures. Because the 8v specs ain't even close.

 

Errr,
Whipping out pistons ( or stripping the engine) is not for everybody though and is certainly more involved vs an additional MLS gasket to another that will compromise quench/squish areas (very abundant on an 8v EA827 motor). However this compromise is a very small penalty, to efficient combustion and the flame travel using the current NASP engine as a base. * I should also add the counter flow design of the EA827 8v and the excessive valve shrouding is already penalty to burn rate . To put into perspective the effect of this quench topic, one has to think of think of the significant torque increase and response from forced induction and tuning to match when the engine is boosted. Recall this engine was last tested by myself achieved ~ 130lbft on a DD rolls over a fairly wide range of low-mid rpm.
I really do not think that the owner will be bothered when the engine torque ramps up to a near potential 190lbft over a similar range of rpm. Retaining the original squish area and clearance to a point would make a more efficient engine possibly raising the det limit and allowing more spark adjustment for a given CR, fuel rating, AFR, load and engine speed, thus more torque over the hypothetical torque limit that was just mentioned. We would also require lower compression to further increase the det limit and run the spark closer to MBT. Overall this means correct pistons and more cost.
The same compromise occurs in boosted VR6 engines with a spacer by the way, which in a "mild" 311PS@6000rpm and 340lbft@4200rpm transforms a humble Golf 3 or Corrado into a bit of handful!

Fettled 2.8 NASP VR6 power and torque from a 2.0 8vT

Assuming all the other hardware is ready and consistant we have,

• Method 1 2 MLS gaskets paving the way for a potential 190lbft engine from 2-4k rpm and 180PS@5000rpm with some compromise in quench.

• Method 2 Or a full pistons w similar CR/engine rebuild for a potential 195lbft engine for the same revs 2-4K and 190PS@5500rpm. We are still using a used 5303 turbo and same cam.

Base engine was at least 130lbft 2-4.5K rpm ( using DD Toyotecwerke baseline 24-07-11) meaning an increase of 46% of clutch torque and possible axle torque from method one.
Or 50% increase in torque and accel in gears for the more costly and time involved method 2.

For the extra 4% in doing it the costly and "right way" will it be worth it?

For the cost of method 1 ABF/VR6 conversion or 1.8T looks expensive.

For the cost of method 2 BAM/APX engine starts to look like a bargain!

Rods and main shells can be checked without stripping the engine as already you know.
None of the above methods is expected to lead to an engine fail.

Perhaps I need to get out there with my G meter and build up a more data on this vehicle as it steps through various hardware changes.

 

His engine has recently been built. So a known quantity and easier with stacked gaskets as suggested.
But in an unknown engine, if the head is off anyway, and the sump too for an oil drain to be added it is not hard to undo 8 nuts and pull the rods to determine wear on shells, and check ring gaps and carbon build up of ring grooves and oil control rings. Especially when it is presumably going to be given a much harder time than when it was running NA.
It is not a full on complicated build using new forged pistons and rods. Keeping it simple and with carefully checking of oem parts should still perform well I would imagine. Still will need an LSD to put it down properly mind.

 

An unknown engine is exactly that - unknown.

Based on the dyno test, I would say this engine is very healthy with no blow by. A leak down test can be performed to add confidence to the dyno result and to avoid removing pistons.
If oil pressure is good when hot (oil >90C) and in idle ( gauge pressure > 1.4bar) I would be most confident the shells are in good shape. A good time to check would be for sump drain modification.
Forged pistons and rods add cost and are NOT required for this level of build.

LSD and transmission ratio/type is a different topic though important to desired application.

 

Who said rods and pistons were needed? Why are you quoting me, and then I am having to quote myself again?

I am only suggesting checking certain things when an engine is all but stripped for the sake of 8 nuts. On an unknown engine that other readers of this thread may have, it would be a shame to build it all up with 2 new headgaskets, all the turbo kit, install the engine and management, and then find when it fires up that there is an issue requiring a strip down.

 

Pistons and rods were mentioned as doing it the "right way" by someone else, earlier in the thread. Just seems like there are alot of opinions on this subject without any real world proof.