#301
|
||||
|
||||
No rush to get it back together, I'm sure I'll think of a few other jobs to do at the same time! Bit of a shame as a photoshoot for Volksworld feature was planned for last week, won't be happening for a little while now. I now have the shortblock sat in the garage
__________________
http://www.ricola.co.uk |
#302
|
||||
|
||||
Sorry about the bad luck. Keep your head down and before you know it, you will be back stronger than before.
__________________
NO_H2O 72 1302 Smack Black GL 73 Bus (2L CIS Powered) 66 Beetle, 73 Standard Beetle 72 Pinzgauer 710M Volksport Kafer Gruppe |
#303
|
||||
|
||||
Hard luck man Just keep thinking of those fun quick bursts of speed while you're rebuilding it to get you through. For my 2 cents, I recommend building it right, with forged rods/pistons now, even if it means waiting a little longer to get it back on the road. Do it once and be done with it, don't risk overboost, or bad gas or whatever blowing up the motor a 2nd time because it's on edge. You've got one of the sweetest projects on this site and I'd hate to see it undermined by another motor blow.
Also, now would be a good time to paint match some engine bits, not that I'm suggesting anything |
#304
|
||||
|
||||
Paint match what? I think you can go too far with colour-coding, I prefer the OEM+ look to modifying. If it looks right then it normally is!
I just dropped by a local subaru specialist (API Impreza) and they are going to look over my parts and advise the best combination (3 engines to chose from!). I will more than likely go with forged pistons, the sti rods are already forged. They can also get early heads machined to the 2.5 volume and shape which would avoid detonation. I'll finish off with getting it mapped properly, not just a generic aftermarket one..
__________________
http://www.ricola.co.uk |
#305
|
||||
|
||||
With the old block unusable in its state I decided to bring the final plan forwards... So, with a bit of hunting I found a 'rebuilt' 2.5l STI shortblock on ebay.
Final build will consist of 2.5 sti upgraded with forged pistons, V3/V4 sti heads which I will rebuild, upgrade one of my turbos to td05-20g, new bigger injectors, new oil modine, sump baffle plate and probably some other supporting mods being topped off with a remap on an ESL daughterboard, probably by Bob Rawle when he visits API. The shortblock as I received it. With some thought I decided that I will always feel uneasy about the stock pistons as they haven't got a very good reputation. After a chat with David at API (well respeced Impreza engine builders only 5 miles away from my house!) I decided to go with some forged pistons. Supertechs have a good reputation for not being rattly like most and API have experience of them so that's the way I have gone. The stock rods are good for 450bhp ish as they are the latest spec ones. My goal is a good 400bhp. Time to split the block as the cylinders needed honing to fit the pistons. It would also give me a good opportunity to inspect the 'rebuild'. The big end bearings were supposedly new! I've replaced them with ACL bearings Main bearing clearances checked with plastigage, they are all good, as are the bearings. Luckily this is the better nitrided crank too.. Block halves back from API after being honed, they have been done to 3.8thou piston clearance. Here's the first supertech piston, I've gapped the rings to specs.. I'm quite enjoying this engine building lark, this is my first attempt!!
__________________
http://www.ricola.co.uk |
#306
|
||||
|
||||
Your being thorough with measuring bearing clearences and all, well done!
Pistons look nice indeed. Liner thickness seems plenty for 400-500 hp too :-) |
#307
|
||||
|
||||
The stock 2.5 blocks are at about their limit at 500bhp so I'm well within that. Any more and you have to either peg the block around the cylinders or press in an insert around the top of the liners which emulates the closed deck block design.. I had to draw the line somewhere!
__________________
http://www.ricola.co.uk |
#308
|
||||
|
||||
Glad to see your back on it Rich,I have heard good reports about API on scooby forums so I would say your in good hands there .
Sorry for the hi jack, but do you use a porsche starter or other high torque unit ? Regards Graham
__________________
gee dub |
#309
|
||||
|
||||
Hi Graham,
Just the standard fitment Porsche starter for the G50, I think they have different depth engagement for the pinion gear through the years (trans) so you need the right one for your flywheel.. Rich
__________________
http://www.ricola.co.uk |
#310
|
||||
|
||||
WRX/Porsche Karmann cabrio 1303
Quote:
I just spotted a small pic of your car at the Pod, in the December issue of the Volksworld Mag, got to say it looks the dogs.
__________________
gee dub |
#311
|
||||
|
||||
I saw the car IRL there at VW-Action. Its even more impressive standing next to it, believe me
|
#312
|
||||
|
||||
Block ready to go back together with new seals, note tape on rod little ends to avoid the risk of scratching the bores on assembly.
All torqued and sealed up.. first piston going in... all pistons in, you have to make sure they are all orientated correctly as well as positioning the piston ring gaps too V4 STI cylinder heads stripped for refresh. All valves cleaned up, re-lapped in to the heads and then ready for first lash measurement. These heads use under-bucket solid shims which come in various different thicknesses and you change shims to get the correct clearances. I knocked off any sharp edges in the combustion chamber to help avoid detonation, this can sometimes be an issue when fitting 2l heads on a 2.5 block due to the slight cylinder diameter mismatch You can see one of the shims sitting on top of a valve. Lots of measuring! and measuring, then swapping shims Ready to go on the engine! ARP head studs fitted to give better head gasket clamping under boost Back to a longblock! I had to fit the cambelt and re-check the valve clearances as the cam loading can change things. Luckily only one shim needed swapping after assembly. V3/4 cam covers were cleaned up and treated to some VHT wrinkle paint, note one on left hadn't had any heat applied ot get the wrinkle effect started yet. Coolant manifold needs modifying to clear the central 2.5l breather pipe. Now I just have to decide what turbo and injectors to go with!
__________________
http://www.ricola.co.uk |
#313
|
||||
|
||||
Turbo and injectors choosing is the fun part!
I noticed these heads seem to have more fillings between valves, suggesting a higher stock CR then others I have seen pics of? Nice job on the assembly and tnx for the pics! Out of interest: what are the intake and exhaust valve sizes on these 2,5ltr engines? |
#314
|
||||
|
||||
Looking good so far.
__________________
NO_H2O 72 1302 Smack Black GL 73 Bus (2L CIS Powered) 66 Beetle, 73 Standard Beetle 72 Pinzgauer 710M Volksport Kafer Gruppe |
#315
|
||||
|
||||
Wally, they are the early so-called cloverleaf style heads, I don't think the compression was originally any different. Combined with the 2.5 block and 1.6mm head gasket these should give about 8.2:1.. The heads are 2l, sorry, didn't measure the valve sizes but they are standard subaru, just being sti the exhausts are sodium filled.
__________________
http://www.ricola.co.uk |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
|
|