Thanks clear message on this ,

As I said , Matty is on my list of calls.

I would prefer the STI stronger piston/rod components but a short blocks probably fine , Target is restore what I had appx 320-340bhp.(adjusts on Kinguwa Acutuator spring rate / to 1.2 or 1.4 boost pressure on Simons twin maps )

And If I re-used my WRX heads I would not need to touch Simons map.
I am thinking I might leave it like this.

 

As above please speak with Matty,short block will be cheapest option,but if you know how to build the engine,then you can build good engine for reasonable money

Parts you can buy easily from US too for reasonable money and will cost you lot less,about the polishing crank,I wouldn't do that,new crank cost around £280

For £1500 you can have everything what you will need for forged build

Running AVCS on WRX this can be problem,but can be easily sorted if you can source JDM WRX ECU,which can run AVCS or second option modify yours existing loom to run AVCS and using STI ECU which is no problem,pinouts are available

Hope this help

Thanks,Jura

 

For Andaru's benefit , I really laughed.
but mine was white and rust colour , but it did have Twin Carbs.
And I only live with the Ethel mermans.

 

Jura , Ok Im on the pace for a build

but Im not going to do the AVCS on a 300WRX ,
its overkill for 320-340 , it has implications to my 5spd box , clutch , brakes etc

I do fancy getting the bottom end sorted though. So I will ring Matty and see what's available. Cheers everyone. Im off to bed its a hour later over here.

 

Yep, make sure it's an 8 bolt one from late classic/newage. Swap your oil pump, heads and pistons across. Boom

 

Ive just sent a pm, I can probably help out with a decent spec 'budget' short engine. You have to be wary of used engine, you really can't tell how good they are, ive just stripped a V8 STI short engine, my Customer bought it for good money as a good runner, one bore has alot of corrosion and the bearings were close to failure (copper showing). It probably was running ok, but not for much longer!

 

Agreed on not knowning the condition of a used engine! I have just stripped a V5 sti due to piston problems and the bearings were the same, down to the copper!
I always find NA engines have had far less abuse and obviously much less stress in them, cranks, bearings and bores usually mint

 

Less abused? You have to plant your foot to the floor to go anywhere and N/A owners only check their oil once every 5000 miles

 

Seen it for years with cars, NA engines are always fresher. Zetecs years ago when I was turboing them, like new inside.
Doesn't matter if you have to work them hard, they still only making 130hp.
I don't really care if no one believes me, I'll keep gobbling the cheap cranks and engines up you lot can keep buying dear stuff, doesn't put me up not down

 

So PMs are out to recomended SN contacts. I have given myself to Jan 2 to choose and one of them will have me back on the road in New year.

Thanks for the advice to all .

 

Turbo or NA?

 

Because wrx turbo engines get well looked after and have such an easy time in comparison?

 

Not sure if I would use NA engine as short block,just due assume NA running higher CR(Compression ratio),pistons are possibly higher compression and rods not sure if they're strong enough to hold high enough boost and crank too,seems is OK,but still I would rather go with used JDM STi engine like short or long block

Depends on target I would say,but in most cases used STI block will fits all requirements if money are issue and forged rebuild is not possible,that's my view on this

Thanks,Jura

 

Pistons are obviously not suitable and need swapped for turbo ones.
However that crank, rods and block is identical to WRX

 

I read Juras qualified comment , "Depends on target."

Lets try to focus on this for a moment :

I have(had ) about 320-340 bhp and a slightly worn 5 spd gear box.

As I don't have much cash and that's not changing till the kids get to 18.
then Im going to be sticking at <350 bhp .

So Im left with asking myself do I need a Sti block ?
However desirable it is for upto 450 bhp. I should have bought an Sti car.

So Im really thinking :

a) Find a NA short block and do what boosted says.
new gaskets/shells/ my WRX pistons.

b) Buy a used long WRX engine and drop it straight in.


c) Find a used short Sti block and put my WRX heads on it.

Right now option b is looking most likely at less than 500 quid , and still gives me the option to do a) or c) later in relative comfort if I should so wish.

The 5 spd gear box can be replaced at anytime for around 300 quid so that's not really a KO for any of this.

Unless anyone see's problems with this power level on used WRX engines , Im inclined just buy another one and fix the old WRX one up a bit better for the next time.

Comment ?

 

Used wrx block will of been subject to more abuse/use than an NA block, so will need definite inspection and bearings etc.
So why not save money and hassle and buy an NA block, if you just want your car back on the road DONT even bother splitting the casings, just home the bores and fire your pistons in in, if you home the bores well you will not need new rings.
Use your 10mm oil pump and some new head gaskets, head bolts will go again.
So your looking at NA engine- £100, HG's £40, oil and filter £40, antifreeze £20, three bind gasket £20. Circa £220 rebuild.
Oh and I strongly advise you run without an oil cooler (modine)
You will never clean yours out properly. Dishwasher does a good job of the sump and oil pick up however.
The above is exactly what I did to my WRX when it ran the big ends earlier this year, except I reused the head gaskets with a wipe of hylomar, and my NA engine only cost £60. Oil and antifreeze is free to me.
So was less than £100 to re build, still going strong 8 months and 7000miles later at 300+bhp.
It's given me time to get the bits and money together to build a "decent" engine (although the cheap and nasty one is still going strong lol)
I understand the family commitments, on exactly the same boat myself.
If your smart it doesn't have to cost the earth.
Oh and my super-duper engine is based on an NA block and crank because I believe there is no difference in them over a WRX one.

 

Thanks boosted , I understand the cleaning issue, I have built several engines for myself over the years and for a rebuild I normally go through two rolls of cleanex towels and that's actually why I would be concerned about regrind of the crank. I had an engineering firm do 2 re-builds on my first Spitfire and eventually found the reason for repeated fail myself as swarf in the crank. A futher rebuild by a firm doing my Lotus went the same way, and so since this experience in late 80's. All engines I have subsequently done, I have cleaned and re-assembled everything myself. On a mini engine I had a new 13 row oil cooler, and that was fine. But with the gearbox sharing the oil you were asking for trouble if not.

I would have choosen to do a new oil cooler on the WRX anyway as when I checked the magnet sump plug I found it looking like a christmas tree.

Your idea on the NA block therefore makes very good sense as the crank will be in good condition. When you check the bearings and find them still clean / no copper grining through then its a simple new bearing replacement. Id have to check my WRX pistons and personally Id like to use new rings after a hone, but assuming the pistons are still good its a low cost alternative. I appreciate the photo's and experience to make this option a possible.

Im going to scour the net for a bit , and see what I can find.

 

No probs, here are the bearings out of that engine;

 

That's interesting isnt it Not much wear on the NA bearings,
you could put them back in and run another 50k .

I wonder how big ends look on a WRX engine at same age.

 

forgot , When you put them all back with WRX pistions I would keep the Rod combination the same & check the weight of the rods , pistons match and polish up them to within 2 g

 

Yep that's what I thought, kept them for a rainy day
[/QUOTE]
I wonder how big ends look on a WRX engine at same age.[/QUOTE]
Facked!

 

Well I have looked to several options including costing out advice from Boosted which is still the cheapest way back on the road but I have decided for STi block as you and the Shrek amongst others advised. The sti pistons particularly are better for my tune 1.45 bar .

After loosing the reasonable WRX engine , Im waiting for answer from Matty on a used Sti Long engine , if that's not available for the money
I have , then Im going to take a rebuilt Sti short block and put my WRX heads on it. Best regs Linksfahrer

 

I will be interested to see the condition of crank/bearings in a used sti engine. Keep us posted

 

Matty was able to do a long sti , but as I didn't need the heads and am short of funds , I have just ordered a short block sti from Andy at wmsracing its coming for a reasonable price with a new 11mm pump ACL bearings Honed with Sti pistons new rings. This makes sense to me because I expect I have already given the original WRX pistons a hard time with that boost peak. I will be running 1.45 bar again on the TD05 16G so its nice to have a safer margin for the 320-340 bhp on tap. I will post when I get the old WRX engine out , then we will see what a 107 k PPP engine / crank wear looks like , might be a while as the weather is terrible , I doubt if I will get into the garage before March.

 

Remind me, is it a big end failure you have suffered?

 

It was . MBC jammed , Boost alarm went off , I saw well over 2 bar on the gauge , it had spiked badly. Obviously you lift off but it just takes too long to reduce the over pressure and then tick , tick , tick , I had just joined the motorway , so just coasted it along , but a mile later it had developed to tack , tack , tack. I rolled out of the exit then switched off.

I had thought before I fitted the Ebay MBC for 10 Euro that , it would be ok for a bit , the new WG actuator was already in customs. Its tough luck , but with 107k on the WRX PPP and 2-2.5 bar , I am not entirely surprised.

At least now the sti bottom end, should do well with the power asked.

 

Sounds to me like the high mileage has done it.
Over boost shouldn't wipe the big ends out immediately, remember the sti bottom end is no stronger in this way, it uses the same bearings and oiling method. The rods and pistons are stronger, but this was not your failure.
Having said that new bearings and stronger pistons/rods will be great with your setup.

 

I was looking at your post on the Engine build thread re your TD05 20g ( or hybrid 19g as you put it ) . Do you think the gas temp into the TD05 16G is a big restriction to developing more power past 330bhp ? , I did try 1.7 bar briefly for a gigle on 102 octane ARAL fuel on the MBC at least It felt like it gave a lot more ooompph in spool up.

I say this because I have a twin map and I can switch over from 1.2 to 1.5 its no big deal to change to trim that to 1.6 once I have the new WG acuator springs / sti bottom end in. I also have a TMIC thats 25 % bigger than the Sti 8 one.

 

1.7 bar will feel good at 3500rpm, the turbo has no problem supplying the boost at this rpm/flow too. However, try that boost at 6000rpm...
The 16g just can't flow enough air, if you look at a compressor map for a 16g, it's max efficientcy is at 1.0 bar, and it will only manage more boost under certain circumstances (ie lower rpm/ less cfm)
And to answer your question on gas or air temp, yes it is a problem, if you have ever monitored the temperature exiting the turbo you will see 100 plus degrees! Heat is a result of the turbo spinning too fast and causing friction upon the air through turbulence and compression etc. Bigger turbo will always be more efficient and run lower turbine speeds for a given flow.
I understand you have a big Intercooler, but it's not an efficient way of running more power, essentially you are superheating air through a small turbo spinning way faster than it's designed to, creating excess exhaust back pressure etc, then the energy you have just wasted heating up the air then has to be removed through the intetcooler (reducing the mass, reducing the boost pressure) the turbo tries to keep the pressure up and can't manage, escalating the problem even more, until you get to the stage you can't make any more boost and you find the boost gauge dropping (up the revs as the engine demands more flow)

 

Mine is set to 1.45 peak and holds 1.4 to the redline, different spec engine obviously.

Also my shortblock was from Andy @ WMS. Great guy!