cygnusx1 Posted November 10, 2007 Share Posted November 10, 2007 Corrected numbers are better for before/after comparisons though. Unless you are trying to figure out how mother nature effects the numbers. Quote Link to comment Share on other sites More sharing options...
slownrusty Posted November 10, 2007 Share Posted November 10, 2007 John - Fantastic and crazily inspiring....you have been one of the force drivers to get off my rump and get my L28ET build finished....I got some pics coming today for you! Yasin Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 10, 2007 Author Share Posted November 10, 2007 Post up the uncorrected chart! I want to see what it actually made today w/ this cool weather we've been having. Justin Here are uncorrected versions. They are a bit more generous.. 6/30/06 11/9/07 Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 10, 2007 Author Share Posted November 10, 2007 Good work, John - Makes me want to get back to work on my junk and get it out to the track. Rick, your car has been an inspiration to me. I've spent most of my time trying to get in the same ballpark performance wise. It seems I'm a couple years behind you. Once you get the Buick V6 done the game will be over. I don't think all do, but..... Am I the only one that thinks that way? No... good post-i am getting ready to dyno my z -has 1500 miles on new 2960 stroker motor.my turbo has a stock turbine side that has been remachined for stage 5 wheel and waste gate hole has been ported.compressor is 60-1.has stock internal waste gate.have to swap exhaust manifolds because of a leak.have spare ready to go-ported and machined.thinking about getting a new garrett gt ball bearing turbo-and redo down pipe to 3". Your car sounds a lot like my old setup. I had problems with the internal wastegate blowing open and bleeding boost. The 60-1 is a great turbo for the L28 but, in my opinion, needs at least a 3" DP to bring out it's potential. John - Fantastic and crazily inspiring....you have been one of the force drivers to get off my rump and get my L28ET build finished....I got some pics coming today for you! Yasin Thanks Yasin. I look forward to the pics. Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted November 10, 2007 Share Posted November 10, 2007 Nice job John!! It's been a long time coming. Quote Link to comment Share on other sites More sharing options...
510six Posted November 10, 2007 Share Posted November 10, 2007 Those are great #`s esp with that small of a turbo.makes me want to get back on the dyno for final tuning. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 10, 2007 Author Share Posted November 10, 2007 Nice job John!!It's been a long time coming. Z-Gad, The dyno shop I went to here in Portland is named RRev Motorsports. They are a big Supra shop and asked me if I knew you being that I was a Z enthusiast and all.. Apparently they were impressed with your setup... Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted November 11, 2007 Share Posted November 11, 2007 Z-Gad, The dyno shop I went to here in Portland is named RRev Motorsports. They are a big Supra shop and asked me if I knew you being that I was a Z enthusiast and all.. Apparently they were impressed with your setup... Wow, I'm humbled... I am familiar with RREV Motorsports as well... They do some impressive stuff. Amazing how small the racing community is... Quote Link to comment Share on other sites More sharing options...
BayAreaZT Posted November 12, 2007 Share Posted November 12, 2007 Impressive gains. It's good to see some data on the difference between the two setups. Makes it tempting for me to ditch my 2.5" DP and go with a 3" when it's time for a rebuild. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 12, 2007 Author Share Posted November 12, 2007 I was looking over my dyno graphs in the WinPEP software (awesome tool BTW) and wanted to better understand the differences between runs 9 and 10 on the 11/9/2007 graph. Basically, what was the reason for the delta between the two runs? For run 010 I changed some values on my fuel MAP which translated to a more torque but much less horsepower. Notice the rich condition on run 010 indicated by the large dip at 5863rpm. I obviously have more tuning to do but this really shows how power is affected by AFR. My observation is that an air fuel ratio of 12 to 12.2:1 makes best power. Of course, keeping EGT's down is a HUGE factor to consider in addition to tuning for peak HP/TQ At 5863rpm: Red/Run 9 was at 11.91 AFR (443.78HP) Blue/Run 10 was at 10.54 AFR (400.07HP) At 4674rpm: Red/Run 9 was at 11.40 AFR (459.73TQ) Blue/Run 10 was at 12.02 AFR (468.92TQ) Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted November 12, 2007 Share Posted November 12, 2007 I think its a pretty well accepted fact that 12.5:1 is ideal conditions for max power in petroleum powered internal combustion engines (all other things being equal). Dave Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 13, 2007 Administrators Share Posted November 13, 2007 I think its a pretty well accepted fact that 12.5:1 is ideal conditions for max power in petroleum powered internal combustion engines (all other things being equal). Not everyone would agree I've never seen an engine that was 'happiest' with one AFR across the board. I've only occasionally seen an engine make MBT (mean-best-torque) at 12.5. Most NA motors are a bit 'soft' at 12.5 and frequently even at 12.8. I commonly see MBT in the 13.3-13.5 range, sometimes leaner, sometimes richer, and never the same from one RPM range to the next. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 13, 2007 Author Share Posted November 13, 2007 I think its a pretty well accepted fact that 12.5:1 is ideal conditions for max power in petroleum powered internal combustion engines (all other things being equal). Dave Dave, At 12.5:1 my EGT's would be too high. In my WOT datalogs I'll tolerate spikes to 12.2 and down to 11.5 but with average of 12. That's the goal even though I haven't got it perfect yet. BTW, I figured out what you meant regarding the graph colors. You are right. It was confusing. Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 13, 2007 Share Posted November 13, 2007 I'll agree with Ron Tyler, we found past torque peak on JeffP's engine we started pulling fuel like crazy and kept making horsepower and EGTs were still in line with his tastes (and they are finnikey tastes...) At 12.5 across the board, after torque peak, the EGTs were skyhigh, and we were glowing the turbo and three feet of downpipe bright yellow-orange! Took out fuel and that stopped quickly enough. No engine will be happy with one AFR for all speeds. And suprisingly, they will tolerate a lot less fuel in some places as compared to others and still make power! Some of Jeff's bins past torque peak were in the mid/high 13s under boost without EGT issues or any detonation! Quote Link to comment Share on other sites More sharing options...
1 fast z Posted November 13, 2007 Share Posted November 13, 2007 So Tony your saying that when the turbo was glowing red, you took out MORE fuel, and that lowered EGT's? Seems backwards to me. I can see adding timing after peak torque, that would decrease EGT's. Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 14, 2007 Share Posted November 14, 2007 Pulled fuel. Went from 12.5 to as low as 13.8! The horsepower kept increasing, the pipe stopped glowing. I thought the same thing but Lance said 'pull fuel' and when we did even more power came, and the glowing ceased. I mean, if you could have seen how we were beating his car you wouldn't have believed it. I have some video, I should probably upolad some to YouTube...meh! When I get time. Quote Link to comment Share on other sites More sharing options...
1 fast z Posted November 14, 2007 Share Posted November 14, 2007 Still doenst make sence to me though, I can see the HP increasing, but not the EGT's lowering when pulling fuel. Quote Link to comment Share on other sites More sharing options...
Mack Posted November 14, 2007 Share Posted November 14, 2007 nice numbers man! Ill echo everyone else when I say that "hopefully, when I get my engine done, Ill have numbers that good!" on the pulling fuel thing/reducing EGTs... ill say this.... What COULD be happening is at upper RPMs, running super rich the mixture doesnt have time to burn completely in the cylinder, thus when the exhaust valve opens, it continues to burn all the way out the turbo and exhaust system. Pull fuel, solve problem. Quote Link to comment Share on other sites More sharing options...
1 fast z Posted November 14, 2007 Share Posted November 14, 2007 I say false on macks statement, as the burn rate does NOT change with more fuel, I bet they added timing to help EGT's. You can put tons of fuel, but it only burns at one rate. Quote Link to comment Share on other sites More sharing options...
jgkurz Posted November 14, 2007 Author Share Posted November 14, 2007 I say false on macks statement, as the burn rate does NOT change with more fuel, I bet they added timing to help EGT's. You can put tons of fuel, but it only burns at one rate. In my experience, adding fuel to richen your air fuel ratio will never raise EGT's. Too much fuel will bring down power but it will also cool the charge hence lowering EGT's. Typically, advancing timing will reduce EGT's but then you get into detonation problems if you go too far. It's a fine line. I do agree that to achieve optimum efficiency from an engine you cannot assume one AFR is correct for a broad range of RPM. However, I think it's extrordinarily difficult to 1) determine what AFR is best at each RPM/load point and 2) to tune to the desired AFR once it's know. For that reason I make some broader generalizations on what AFR to run at what load point. Quote Link to comment Share on other sites More sharing options...
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