240zip Posted October 31, 2010 Share Posted October 31, 2010 Did a complete rebuild (engine, transmission, and triple webers). The engine is a 1981 block with an E31 head, 6 into 2 MSA headers, and Weber 42DCOEs rebuilt by Rex Chalmers. Brian Blake did the head and installed a moderate street cam. Intakes were ported, polished, and matched to the DCOEs. I was concerned about the compression, so I put some 108 race gas into the tank. Rex did an amazing job with DCOE's ... I'll post the baseline parameters (they're very close to the baseline for the 3500GT which these came from). the audio is terrible. it always seems when people film their DCOE's it sounds like a sewing machine going mad, the valve noise is not nearly that loud in reality. we go to the dyno in about a week. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 31, 2010 Share Posted October 31, 2010 (edited)  +1 for DCOE's they always get a bad rap but I think they are great.  Engine sounds good.  That is about the usual sound from the valves when making a video with most cameras. Sometimes holding your finger over the mic fixes the sound problem and makes the high frequencies sound more realistic. Edited October 31, 2010 by cygnusx1 Quote Link to comment Share on other sites More sharing options...
240zip Posted October 31, 2010 Author Share Posted October 31, 2010 we'll see what happens at the dyno ... my 'hope' is for 180HP at the wheels. I think it will come in around 170HP. It should still make for a fun car to drive. I did a complete suspension rebuild and even swapped over to a R180 LSD from an STi. It has the five speed transmission. The goal was a fun weekend driver that will also see some limited track time. Quote Link to comment Share on other sites More sharing options...
z-ya Posted October 31, 2010 Share Posted October 31, 2010 we'll see what happens at the dyno ... my 'hope' is for 180HP at the wheels. I think it will come in around 170HP. It should still make for a fun car to drive. I did a complete suspension rebuild and even swapped over to a R180 LSD from an STi. It has the five speed transmission. The goal was a fun weekend driver that will also see some limited track time. Sounds good. Tune it with the lowest octane rating you plan on running on a regular basis. Standard bore? 81' blocks had dished pistons, right? If that is what you are running then the CR should be around 8.5:1. With flat tops around 10.2:1. Quote Link to comment Share on other sites More sharing options...
240zip Posted October 31, 2010 Author Share Posted October 31, 2010 well z-ya, standard blocks did have the dished pistons, but I used flat-tops .5mm over with the E31 ... I have a 2.8L with flat-top pistons bored .5mm over and an E31 head yielding 10.32:1 compression. Stock cam was removed, and a 260 duration. .450†lift on both intake and exhaust was installed. I have 6 into 2 into 1 headers flowing into a 2.5†exhaust with a free flow resonator and Dynoflow muffler. My base elevation is 5000' (Denver). I have a Pertronix ignitition with MSD 6a. The settings on the carbs are ... 42 DCOE 32 3.5 135 F15 155 55F2 45 200 were the baseline settings. We swapped elivery valves to 175 instead of the 200s. We'll refine it further with the dyno. I hope I can get by on pump gas. It's fun running race gas, but at nearly $6/gal, it gets expensive. Of course my European friends will say, "$6/gal ... so what's the big deal?". I'd like to wean it down to a mix of perhaps 1/3 race, and 2/3 91 octane (the best we can get in Colorado). Quote Link to comment Share on other sites More sharing options...
240zip Posted October 31, 2010 Author Share Posted October 31, 2010 Some close-ups of the work done in the engine bay and the throttle linkage. I had a vintage fuel filter (Filter King) and we fabricated some simple things (for the spring and the trottle linkage). I selected the Filter King because I saw some vintage racing shots which showed the same filter. Also the bracket for the MSD is custom. Running the MSD 6AL and the Pertronix. Not sure if we'll keep that pressure regulator, will likely get a Holley or Aeromotive and think about another location for it. Quote Link to comment Share on other sites More sharing options...
zbloke Posted November 1, 2010 Share Posted November 1, 2010 That look very nice, you do know you can set/adjust your fuel pressure with the Filter King don't you? Quote Link to comment Share on other sites More sharing options...
240zip Posted November 1, 2010 Author Share Posted November 1, 2010 I wasn't sure how good the Filter King was with respect to pressure regulation. It mentioned that it removes pressure fluctuations in the brochure, but it wasn't clear how you adjusted the pressure. Quote Link to comment Share on other sites More sharing options...
zbloke Posted November 2, 2010 Share Posted November 2, 2010 Adjusting the Filter King pressure is pretty easy, if you remove the dome nut in the center underneath is a lock nut and set screw, slacken the lock nut and turn the set screw = adjust the pressure, just need to hook up a gauge and your sorted Quote Link to comment Share on other sites More sharing options...
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