the sawtooth build thread Options

[sawtooth]

Wanted to start a build thread for my na suby conversion. The car is my newly acquired '73 2.0L fi. It is very clean, appearance group, 2nd owner, 88K. I currently use it as my daily driver.



I want to do a suby conversion because I believe the overall package will have the performance, drivability, and dependability I'm looking for.

EDIT: I've changed motor selection slightly and am also taking a bigger plunge by going with a suby trans, see Post #49.

[charliew]

Matt's been around a long time and is very knowledgeable. I just wish I knew what he knows and could always remenber all of it. I enjoy reviewing that thread. Google cfm flow to hp and torque, there are formulas for power. The suby has a pretty good ve but from my memory the good heads flow about 220-230-240 cfm on the intakes na. When you go to 14 psi on the turbo you double the cfm flow to the cylinder thats how a 2.5 can perform like a 5.0 but still get the fuel economy of the 2.5 off boost if you leave the ports stock. When you go to bigger cams on na you always loose some lowend power on any motor, the same with bigger ports. My google button found 1 hp = 1.45 cfm There are charts somewhere on this.

For me 250 is VERY optimistic. That will probably be on the lean scary side on av gas with 11:1-12:1 compression, which means a built motor. Probably a 8000.00 motor if you pay for it.

[sawtooth]

Matt's been around a long time and is very knowledgeable. I just wish I knew what he knows and could always remenber all of it. I enjoy reviewing that thread. Google cfm flow to hp and torque, there are formulas for power. The suby has a pretty good ve but from my memory the good heads flow about 220-230-240 cfm on the intakes na. When you go to 14 psi on the turbo you double the cfm flow to the cylinder thats how a 2.5 can perform like a 5.0 but still get the fuel economy of the 2.5 off boost if you leave the ports stock. When you go to bigger cams on na you always loose some lowend power on any motor, the same with bigger ports. My google button found 1 hp = 1.45 cfm There are charts somewhere on this.

For me 250 is VERY optimistic. That will probably be on the lean scary side on av gas with 11:1-12:1 compression, which means a built motor. Probably a 8000.00 motor if you pay for it.

I guess for me it comes down to this... say Matt is wrong and I can only squeeze 200chp out of this motor. With the flat torque curve I've seen out of this motor, it has more than enough power to make the 914 feel pretty crazy. It's a good balance for this car. I'm obviously not an expert on any of this by any standard. But I do know from an upgraded STI that I get to drive once in a while that it has an enormous hit, but comes on pretty late, there is definitely a lag waiting for the power to come on. I like the way my car pulls better, it's very strong right from the start. No, it doesn't produce anywhere near the same power at the top side, but down low and in the medium range it is more than enough for me. That, combined with the simplicity of not having a turbo is a winning combination for me. If it's not enough, I could plug-n-play upgrade to an EZ30R to get 300hp without a turbo.

charliew, seriously love getting your feedback, gets me thinking through things. Really appreciate it.
- Dean