How come with half a liter less displacement....
#3
Evolved Member
iTrader: (11)
Dont know that its an Aways thing, Similar sized motors produce similar results. With the STI/EVO you cant mod the stock block sti motor to produce similar power to the EVO without major changes--the stock sti block is good for around 300hp before major work needs to be done and the evo its around 400hp. So I feel sure many owners dont want to spend the extra cash for the extra HP as its a major tear down. Different designs, different intentions for use, diff displacement all determine the operating range of a motor. In this case larger displacement yield more down low with a limited upper end. The EVO can be built to produce all its power up top and rev to an RPM out of range for the STI. Again different designs. It take more then a turbo to differentiate a motors output.
#4
Evolved Member
iTrader: (3)
evos can take MUCH more power than STI's, I believe the limit with STI's are they are prone to ringland failure and by that they are limited to ROUGHLY 400whp, where as the 4g63 is very tough and can take wel over 600whp reliably. Now our drivetrain is far weaker so you will find us paying a lot to beefen up the drivetrain.
#6
Evolving Member
iTrader: (6)
This is a gross oversimplification, but bear with me:
Peak horsepower is generally proportional to bore size. Stroke primarily affects where on the power curve and engine will make power.
So the mere fact that an engine has a bigger displacement does not say very much by itself.
Peak horsepower is generally proportional to bore size. Stroke primarily affects where on the power curve and engine will make power.
So the mere fact that an engine has a bigger displacement does not say very much by itself.
#7
EvoM Guru
iTrader: (1)
Agreed there is some very specific airflow characteristics to each motor that make them stronger and weaker.
Airflow is targeted at lower engine rpms on a sti than an Evo aswell. Pretty obvious when you compare the oem turbos. The oe configuration works well but change one aspect and the system has a restriction somewhere else. I4 motors are easy to do cams in among nearly every other mod so they respond well to airflow improvements
And a Subaru 6 speed is like holding gods ####
Airflow is targeted at lower engine rpms on a sti than an Evo aswell. Pretty obvious when you compare the oem turbos. The oe configuration works well but change one aspect and the system has a restriction somewhere else. I4 motors are easy to do cams in among nearly every other mod so they respond well to airflow improvements
And a Subaru 6 speed is like holding gods ####
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#11
Newbie
iTrader: (1)
Not sure on the techinical side of it but the newer subaru engines seem to be much better then the older ones when it comes to high hp levels on a stock motor. 4G63's in general are some of the most well prepared motor's for handling higher hp on the stock motor that ive seen. Assuming maintenance is kept up with and there arent any 1/2 *** corners cut.
#12
Evolved Member
iTrader: (125)
cheeze. why pussyfoot around the truth. the 4g63 smokes the subi engine in the design department. waaay more reliable at any high HP level. it makes power much easier as well. if you took the fastest top 1000 subis and 4g63s around the country I bet 900 would be 4g63 powered.
#13
Evolving Member
iTrader: (8)
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this guy knows he stuff
Dont know that its an Aways thing, Similar sized motors produce similar results. With the STI/EVO you cant mod the stock block sti motor to produce similar power to the EVO without major changes--the stock sti block is good for around 300hp before major work needs to be done and the evo its around 400hp. So I feel sure many owners dont want to spend the extra cash for the extra HP as its a major tear down. Different designs, different intentions for use, diff displacement all determine the operating range of a motor. In this case larger displacement yield more down low with a limited upper end. The EVO can be built to produce all its power up top and rev to an RPM out of range for the STI. Again different designs. It take more then a turbo to differentiate a motors output.
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#15
This made me laugh. It is a true statement though. I wish I could put an STi 6-speed in my Evo. Seven years later, and with 524whp on our Mustang dyno, my stock STi transmission is still working like a champ. I just wish Subaru motors could have the volumetric efficiency that the 4G63 has. It takes a lot of money to make more than 500whp with a Subaru (reliably).