it's been hard getting anywhere on my CGT while i'm at school.. but my bro just picked this up...
02-13-2008, 05:14 PM
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it's been hard getting anywhere on my CGT while i'm at school.. but my bro just picked this up...
from my machinist.. i had dropped it off before i went to back to school after winter break to have it planed, cleaned a little, and have my valve stem seals installed... i'm bad at documenting projects, but i'll HOPEFULLY get the engine all together this weekend and have some more pics up.. this is torture being seperated from my cgt, not to mention it's been over a year since I last drove her 
.. at least i have the 4kq with me
<img src="http://pictureposter.audiworld.com/114286/head1.jpg">
<img src="http://pictureposter.audiworld.com/114286/head3.jpg">
<img src="http://pictureposter.audiworld.com/114286/head4.jpg">
.. at least i have the 4kq with me<img src="http://pictureposter.audiworld.com/114286/head1.jpg">
<img src="http://pictureposter.audiworld.com/114286/head3.jpg">
<img src="http://pictureposter.audiworld.com/114286/head4.jpg">
02-13-2008, 06:13 PM
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ahaha.. yes garza, i do know a thing or two about engines.. i have the whole engine..
actually i have an entire '91 90q20v.. so this has all been fairly easy, but i always get a very bad case of the "while im in there syndrome".. so every single last gasket on the whole thing is being replaced, everything was cleaned and painted.. i did a little gasket match porting (god did it need it), i got a bag o' snakes for it it, i'll be running 034 injectors.. all those sorts of things
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02-13-2008, 07:00 PM
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Easy big fellah! I wasn't "shine boxing" you!!! :-p
Good thing yer putting it in yer coupe, 20v's are total screamers! Weak bottom though, torque peak is at 4,500rpm. The lighter coupe will help, did you lighten the flywheel? If any engine needs it, it's the 20v, I'd also play with an adj. cam sprocket, advance the cam to get more mid range, I did that w/my 272° cam it makes it much more drivable around town....
02-13-2008, 07:13 PM
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its ok, its ok.. i was just messin with ya too.. but..
my dad drives a 90q20v.. so ive driven the 7a plenty, and the rev's seem too lazy, especially below 4500.. so a lightened flywheel is definitely in the works.. i may skip the gear (for now at least).. as i hope to do some cam work eventually, the stocks are terrible for n/a.. cams are 22x/21x degrees iirc.. that needs to be changed.. and im aiming for a screamer, i dont want a peak in the middle and then have it die up top, i want at least a plateau up to redline. i'm big on hp>tq for this project.. plus i'll have a stock 10v '84 cgt or my 4kq hangin around for town duty
but yea, im hopin this thing'll be fun in the cgt.. ill be doing solid subframe bushings, 2 piece struts from the 90, G60's, and i'm thinking im going to use the 90's cast control arms, and swap the 3bolt ball joints from side to side to get some more castor.. so it should handle and stop better to match the go
but yea, im hopin this thing'll be fun in the cgt.. ill be doing solid subframe bushings, 2 piece struts from the 90, G60's, and i'm thinking im going to use the 90's cast control arms, and swap the 3bolt ball joints from side to side to get some more castor.. so it should handle and stop better to match the go
02-13-2008, 09:18 PM
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Remember, an engine is just an air pump: more airflow= more power...
How you attain the increased airflow can be done in 3 ways:
More displacement/bigger engine,
Spin the engine faster, this can only be taken advantage of by cams, porting, bigger valves,
Forced induction: in most ways, this is the best alternative.
Turbocharged engines act like a variable displacement engine, at full boost (theoretically if the turbo and intercooler were 100% efficient), the displacement is multiplied by the number of "atmospheres" of total boost.
In other words, a 2.2L running 2.0bar of absolute boost pressure should have the same power output as a 4.4L normally aspirated engine, and uses the same amount of fuel.
Now the advantage is off boost or @ low boost the engine acts and consumes the same amount of fuel as a 2.2L, the best of both worlds!
Now to normally aspirated engines. If you can't increase the engine size, you have to spin it faster and correspondingly increase airflow through the head.
This causes the torque and power curves to get narrower and peaky, and even worse move higher up the rpm band.
The extreme example of this are F1 engines, an engineer once described their engine as having a "power spike" instead of a power peak.
With a close ratio trans, this works on the track, but sucks on the street.
The ultimate solution is variable cam timing and valve lift.
For your application, I don't think you can get more than about 180hp without having a stratospherically high torque and power peak.
As long as you put your coupe on a diet, it WILL be quick, but can be MUCH faster....
More displacement/bigger engine,
Spin the engine faster, this can only be taken advantage of by cams, porting, bigger valves,
Forced induction: in most ways, this is the best alternative.
Turbocharged engines act like a variable displacement engine, at full boost (theoretically if the turbo and intercooler were 100% efficient), the displacement is multiplied by the number of "atmospheres" of total boost.
In other words, a 2.2L running 2.0bar of absolute boost pressure should have the same power output as a 4.4L normally aspirated engine, and uses the same amount of fuel.
Now the advantage is off boost or @ low boost the engine acts and consumes the same amount of fuel as a 2.2L, the best of both worlds!
Now to normally aspirated engines. If you can't increase the engine size, you have to spin it faster and correspondingly increase airflow through the head.
This causes the torque and power curves to get narrower and peaky, and even worse move higher up the rpm band.
The extreme example of this are F1 engines, an engineer once described their engine as having a "power spike" instead of a power peak.
With a close ratio trans, this works on the track, but sucks on the street.
The ultimate solution is variable cam timing and valve lift.
For your application, I don't think you can get more than about 180hp without having a stratospherically high torque and power peak.
As long as you put your coupe on a diet, it WILL be quick, but can be MUCH faster....