It has been a while since I have posted here.

I searched around here and a number of other places with no results.

Unless anyone can come up with a good reason not to..... I am building up a phase one EJ25 block with the crank and rods out of a EJ22t. This will effectively destroke the EJ25. This looked to, in the mock up to be a really cheap way for me to build a turbo motor for my outback. I will only need to pick up some rings and perhaps a set of main bearings. I will be using the dished EJ25 piston, and the thicker headgasket, as well as the DOHC heads.

The only detractors I can think of is oil squirters (easily fixed), and the open deck (I only plan on running around 14LBS).

Thanks for the useful feedback.

Josh

by lowering the stroke from 79mm to 75 mm, what compression with stock pistons are you going to have? the EJ22T crank shares the exact same main bearing layout right? diffenetaly need to get new rod and main bearings for this, it wouldnt be worth it not to. and dont worry about the oil squirters( do they even fit into the EJ25 block?)


P.S. matt monson should chime in anytime now.........


~Josh~

Yes the crank fits, the opposite is the set up that many builders make 2.3l strokers out of the 2.2t block and 2.5 crank.

If the bearings do not look bad, or measure out of spec why would you replace them?

As for the oil squirters, they will fit with a drill bit and tap.... not that they are really needed but this is going to be a daily driver, so for a few more minutes work I will keep them.

I do not know how the compression works out, as I do not know the head volume of the heads I will be using, If I get bored perhaps I will find out using this http://www.csgnetwork.com/compcalc.html

The pistons have a negetive deck clearance of about 2ish MM.

Josh

I figured the compression to be 8.3:1 using the thin gaskets!

One last question can anyone make a case with there being a quench issue due to the piston being 2mm below the deck?

case as in SB?

You might want to recal that CR with the piston 3mm down due to the rods being 1mm shorter on the 2.2 VS 2.5.
Eric :)

PS - we'll have some 2.5 rods when we build Aarons stroker.

replacing bearings is just cheap insurance in my mind, if it costs an extra $80-$90 i say you might as well. if you dont, and spin a bearing, you'll kick yourself in the teeth because you didnt want to fork over the extra money. better safe than sorry.


~Josh~

case as in SB?

Huh????

Huh????

One last question can anyone make a case with there being a quench issue due to the piston being 2mm below the deck?

replacing bearings is just cheap insurance in my mind, if it costs an extra $80-$90 i say you might as well. if you dont, and spin a bearing, you'll kick yourself in the teeth because you didnt want to fork over the extra money. better safe than sorry.


~Josh~

If you rebuilt an engine you should always replace all of the bearings, gaskets, seals, rings. I would recommend calico coatings

i personally dont think it will be worth it. there are so many other options that are cheaper than what you are going to do and alot more powerful / pratical

pm me if your interested in my suggestions. i also have some sti rods if your interested.

remember, increased displacement will give you a larger torque increase than power. so what you are doing seems odd to me at least, havent known anyone wanting to destroke a motor before

I feel like I just read this exact same thread somewhere else... ;)

I feel like I just read this exact same thread somewhere else... ;)

More eyes the better, I suppose.

I just wanted to confirm I was not missing something obvious.

This motor will be going in my 97 outback.

Thanks

Josh

I wouldn't want to build an engine with the piston .080" in the hole.

Unless you're using custom rods and/or pistons, you're asking for detonation trouble, IMO.

S.

Destroking normally means you can run higher rpms safer. At least that was result of a few VW builds Ive read about over the years.

I think in this case he wanted a cheap turbo reliable motor. However I really don't understand why you would take rods and crank from a 2.2t motor and put them in a 2.5 motor. Seems backwards.

I am doing a buildup of a 2.2t block with Phase I 2.5 crank and forged Phase I 2.5 rods with Wiseco Hybrid .020 over forged 2.2 pistons. Aparently Wiseco had enough people getting these custom pistons made that they decided to assign them a part number and sell them off the shelf.

All in all my used 2.2t complete shortblock was about $250, Rods and Pistons $800, and I still need to get the block cleaned up and bored .020" over. Pretty darn good for an under $2k investment :)

Brad

The object is to find use for parts that were cast aside from other stroker motors, like the one you built.

I am going to have under $200 into this build. I have no question for a few grand I could easily build a better bottom end, however I think for the money this will be tough to beat.

This should also be simmilar in displacement to your 2.2t stroker.

n2xlr8n ,

I do not think the motor cares what the parts are made out of.

Improper fueling or timing may result in detonation. Tougher parts may have a higher tollerance for improper tuneing, but I am not trying to build super high power motor. Just a fun turbo daily driver for really the cost of some gaskets.

As a note I should have this motor put together later today. In the next few weeks and months, I'm sure we will learn if I made a good decision or if I should have listened to your warnings.

The biggest issue I see, is the substantially smaller ringland areas on these nonturbo pistons.


Josh





Destroking normally means you can run higher rpms safer. At least that was result of a few VW builds Ive read about over the years.

I think in this case he wanted a cheap turbo reliable motor. However I really don't understand why you would take rods and crank from a 2.2t motor and put them in a 2.5 motor. Seems backwards.

I am doing a buildup of a 2.2t block with Phase I 2.5 crank and forged Phase I 2.5 rods with Wiseco Hybrid .020 over forged 2.2 pistons. Aparently Wiseco had enough people getting these custom pistons made that they decided to assign them a part number and sell them off the shelf.

All in all my used 2.2t complete shortblock was about $250, Rods and Pistons $800, and I still need to get the block cleaned up and bored .020" over. Pretty darn good for an under $2k investment :)

Brad

So your saying you don't actually have the 2.2t shortblock? If you do have it that shortblock alone will be more prepared to handle boost then any destroked open deck 2.5.

Why only run 14lbs if you can build a motor and turbo system for the same money?

n2xlr8n ,

I do not think the motor cares what the parts are made out of.

Improper fueling or timing may result in detonation. Tougher parts may have a higher tollerance for improper tuneing, but I am not trying to build super high power motor. Just a fun turbo daily driver for really the cost of some gaskets.

As a note I should have this motor put together later today. In the next few weeks and months, I'm sure we will learn if I made a good decision or if I should have listened to your warnings.

The biggest issue I see, is the substantially smaller ringland areas on these nonturbo pistons.


Josh


No, I believe you missed my point: If you install pistons that are .080" short of being flush with the deck (normally ~.015"), you'll have detonation issues, I'd bet.

You're increasing the quench area, which imo, is a bad thing in an engine that's prone to grenade to due to detonation to begin with :)

S.

I have to apologize. I didn't realize you didn't have the block.

And only $200 in is pretty good! What will that be for? New rings and bearing? You may want to look at a set of ARP head studs as well. If you want I can give you part number and the absolute cheapest place to buy them new ($169-shipped).

Brad

This motor will be dingle ball honed and new rings, the rod bearings did look discolored, so they and the mains are being replaced. Every seal, and o-ring as well as the water pump is being replaced, and a new timing belt.

This is going to be mated to some DOHC heads.

I am going to re-pin the ECU to an early version (90-94) turbo legacy ecu.

Should be fun.

Just an update to this thread. I have put 11k miles on this motor. It has seen between 8~14psi and ran great the whole time.

I pretty much did the same thing this year.

http://forums.nasioc.com/forums/showthread.php?t=1236649&highlight=build+pictures

However, I was running upwards of 30 psi so I lost a piston or two. haha.

But I did make 330 plus whp and a 12.5 @ 112mph!

It was a CHEAP build, and completely experimental, so I never bored, much less honed the cylinders, and that may have exlpained some minor problems at high boost, but had I left it at 20-24 psi, it probably would have lasted a long time.