Stock port S4 NA w/ TWM 54mm
12-02-2006, 07:39 PM
#1
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Join Date: Oct 2003
Posts: 352
Title says it all. Stock port S4 6-port with a TWM 54mm ITB setup. RB header and primarily craptastic exhaust. Haltech E6K and 440 injectors. Engine is in a lightweight Datsun 510. So the car gets down the road real well. 
12-04-2006, 04:09 PM
#4
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Thread Starter
Join Date: Oct 2003
Posts: 352
It's a hodgepodge for the intake. The short block is all stock S4. The LIM is a GSL-SE piece. The primary ports for that and the center iron don't line up well. But the upper intake is the RB Dellorto piece which I needed to mount the TWM. So I couldn't easily swap in one of the many S4 NA lowers I have sitting around because the -SE and S4 upper to lower flange is different. Soooo... I match ported the -SE LIM to the center iron as best I could and went from there.
The power ended up about where I figured. The funny thing was that when we went to the dyno I spent 2 hours trying to find power but only lost or made no gains for every change I made. With the work we'd done with our ITS car I had a real good idea what the engine would want for a/f and timing and I had done a bunch of street tuning and datalogging. Our first pull the a/f was flat at 13.2 and the graph above was from that first pull. We then tried fattening the fuel up some and lost a few hp. Then we leaned it up a bit and lost a few hp. Added some timing and didn't gain anything. Atleast I confirmed what I thought I already knew.
The exhaust on the car is the choke point right now. Has an RB header which is decent but from there back it's crush bent 2" with two restrivtive mufflers. The power peak is at 6800. With the ITS car and a good exhaust we were seeing power peaking over 7200. The 510 is making better torque up to about 5000 than the ITS engine but from there up the ITS engine is even and starts to eek ahead above 6000. I'm guessing with a good (re: too loud for the street) exhaust the 510 would peak somewhere around 7200 and make 175. The owner of the car opted to keep it quiet...and I can't blame him. It's actually a very quiet car.
That little dip at around 4200 was a rich spot I ended up getting worked out.
http://www.ludwigmotorsports.com/bro...510Dynorun.wmv
The power ended up about where I figured. The funny thing was that when we went to the dyno I spent 2 hours trying to find power but only lost or made no gains for every change I made. With the work we'd done with our ITS car I had a real good idea what the engine would want for a/f and timing and I had done a bunch of street tuning and datalogging. Our first pull the a/f was flat at 13.2 and the graph above was from that first pull. We then tried fattening the fuel up some and lost a few hp. Then we leaned it up a bit and lost a few hp. Added some timing and didn't gain anything. Atleast I confirmed what I thought I already knew.
The exhaust on the car is the choke point right now. Has an RB header which is decent but from there back it's crush bent 2" with two restrivtive mufflers. The power peak is at 6800. With the ITS car and a good exhaust we were seeing power peaking over 7200. The 510 is making better torque up to about 5000 than the ITS engine but from there up the ITS engine is even and starts to eek ahead above 6000. I'm guessing with a good (re: too loud for the street) exhaust the 510 would peak somewhere around 7200 and make 175. The owner of the car opted to keep it quiet...and I can't blame him. It's actually a very quiet car.
That little dip at around 4200 was a rich spot I ended up getting worked out.
http://www.ludwigmotorsports.com/bro...510Dynorun.wmv