STI block SOHC heads completed.
12-14-2003, 07:52 AM
#1
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Join Date: Jan 2003
Location: Colorado
Posts: 144
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
STI block SOHC heads completed.
Well all of my annoying questions paid off.. I finished swapping out my block on my 2.5RS.. First I will explain why I did this... My car had been running "funny" for a while.... idling rough, hesitation, and leaking oil out of the valve cover vents.. so I thought great I blew some piston rigs, but to be on the safe side I took it to a dealer... YES A DEALER, and they did a leak down saying that I was leaking 70% from my number 4 cyl. So I thought ####.. I must have a freakin hole in my piston... The dealer said that it would be a minimum of 1400 to take everything apart to see what the problem really is.. I thought to myself.. Funk that!!!!! So I did some research on the new STI block assy.. and asked a million dumb questions and found out that MAYBE all of my stock parts including all of my pumps, etc will swap to the USDM sti block.... So I went that route.. Well I tore my motor aprt a few days ago and discovered that there was absolutely NOTHING wrong with my motor.. Nothing at all.. I did a leak down.. after I turened my right side cam to TDC (will explain ) and did a leak down my self... it only leaked 5 % and this is with a motor that is missing a piston ring (took one off to look at it) and bone cold... pretty good huh? apparently my right side cam sprocket slipped about 30 deg. clockwise and m,y car had been runing like that fro quite some time.. I don't know how, or how long but it was off.... way off.. I paid 1400 dollars for a timing belt... oh well at least I have a new block... but ZI am for sure going to go down to the dealer where I had the work done and ***** thme out.. I won't tell anyone who they are ( Ehrlich Subaru in Greeley CO) because I don't want them to get a bad rap ( $%^$heads) BUt everything does sawp perfectly.. the vent on the top of the sti block is in the way of the water pipe, but some grinding and hammering made room for the vent.. and man it is soo awesome.. my car runs great.. everything works flawlessley.. If anyong has any questions or anything please write me.. I am excited!!! woo hoo!
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12-17-2003, 01:22 PM
#5
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Join Date: Jan 2003
Location: Colorado
Posts: 144
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
no I am not still N/A I have a GT25 DBB turbo.. I am not too sure what I want for the shortblock.. pm me,
12-17-2003, 07:23 PM
#7
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Join Date: Jan 2003
Location: Colorado
Posts: 144
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
yes EVERYTHING swaps.. I have the stock ECU right now with a rising rate fuel pressure regulator.. but I will soon have (Monday) an FTC1 that is made by split second.. it has 3D mapping of both fuel and ignition... it is pretty sweet.. but to get back to your question.. everything swaps.. the sti block looks identical to an RS block even down to the "EJ25" printed on the block... The stock ECU will work just fine though, it will just lower the compression to 8.2:1
12-22-2003, 12:35 PM
#9
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Location: woodstock, ct
Posts: 169
Car Info: 2002 2.5rs
what exactly do you ahve done to your car? did you have the sti block on while you were still na? if so, did you notice anything? would that be a good block to mate with twe heads/ cams/ springs/retainers? worth doing this swap for a na build? what did this cost you all together?
thanks a lot in advance for the multiple questions!
thanks a lot in advance for the multiple questions!
12-22-2003, 01:37 PM
#10
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Join Date: Jan 2003
Location: Colorado
Posts: 144
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
no i didn't run my car NA with the sti block, I have a turbo. This is an awesome block to mate with twe heads, cams, springs, etc as long as they are 2.2 or 2.5 liter parts.I would not recomend doing this swap if you are going to run NA. on a 2.5 RS they have 10:1 compression, and the sti is 8.2:1 compression.. lower compression withoput added induction equals LESS horsepower. When you run NA you want to have higher compression to make more power.. hope this helps.
12-23-2003, 10:22 AM
#11
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Car Info: 1993/2000/2001 GF4 mostly red
Could you perform one more little experiment for us? Would you mind finding the exact volume of the SOHC head combustion chamber? And more importantly, find the volume that the RS piston displaces above the deck? That way, we can determine exactly what the new static compression ratio is of the hybrid motor.
By the way, thanks for verifying this. I am putting ported/cammed SOHC heads onto an EJ257 block next month for my own turbo kit.
By the way, thanks for verifying this. I am putting ported/cammed SOHC heads onto an EJ257 block next month for my own turbo kit.
12-29-2003, 07:05 AM
#14
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Join Date: Jan 2003
Location: Colorado
Posts: 144
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
I wouldn't want to rev past the 6200 rev limit due to the fact that I still have the stock SOHC 2.5RS heads.. If I were to have headwork done than I could rev to about 8000 safe.
