Twin Turbo LSx Rx7 Photoshoot
10-31-2011, 05:53 AM
#22
Yah, but boost controllers also confirm that your not using all "under the curve" power/tq. It's a great build, not trying to diminish it. It just makes more power than the car can put to the ground. Nothing wrong w/ that.
11-01-2011, 10:25 AM
#26
What happened after 6000 RPM? Was it slipping on the rollers, was boost controller doing it, or was there a fueling issue? My guess is that it was slipping on the rollers. Would be cool to see air/fuel ratio plot, an air intake temp plot, timing plot.
What size injectors are you using? Are you using any water or meth injection?
Again, very cool build. Am just interested. Am always trying to learn.
What size injectors are you using? Are you using any water or meth injection?
Again, very cool build. Am just interested. Am always trying to learn.
11-01-2011, 11:23 AM
#28
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What happened after 6000 RPM? Was it slipping on the rollers, was boost controller doing it, or was there a fueling issue? My guess is that it was slipping on the rollers. Would be cool to see air/fuel ratio plot, an air intake temp plot, timing plot.
What size injectors are you using? Are you using any water or meth injection?
Again, very cool build. Am just interested. Am always trying to learn.
What size injectors are you using? Are you using any water or meth injection?
Again, very cool build. Am just interested. Am always trying to learn.
11-01-2011, 03:21 PM
#30
Coils I had were junk. E85 requires a lot more spark energy to burn. The total pull is from 2400 to 6450 rpm, the reason it is graphed by speed and not rpm is that the arcing ignition was making the dyno tach signal go haywire. I've since replaced the coils with a brand new set of LS1 coils. That power peak is right at 5400rpm. Injectors are low impedance 120#ers. And no water or meth injection.
Did not realize that it was running on E85. If I recall correctly, this helps cooling due to the higher volume of E85 burned verses petrol. So, can run higher boost or timing without requiring water or meth.
In regards to coils...you will benefit from LS1 truck coils. There's a thread here linked to where a tech tested LS1 truck coils against LS1 coils & there is no comparison. Either type of truck coil is an improvement. The best being LS2 coils w/ heat sinks. A spark plug was set up w/ an adjustable gap, through a micrometer. Then spark was tested over varying gaps up to some high RPM (maybe 8000 or so). LS1 coils were said to be weak & inconsistent. Truck coils were shown to keep up with gap increases through the whole RPM range.
So, if you are saying that the coils are limiting the the peak to 5450 RPM, as seen on dyno graph, LS2 coils will eliminate the issue. If the power peak is cam related, then OK. Although, typically LS1 head/cam set-ups peak anywhere from 6-7.5K RPM depending on specs.
11-01-2011, 05:40 PM
#31
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Combustion temperatures with E85 are lower than gasoline because unit for unit, e85 has fewer BTUs than gasoline, and therefore burns cooler.
Also, not being a dick, just trying to be informative, but nothing you said about the coils is actually correct. It's all internet hoopla. I had the LS2 truck coils on my car. The ones with the heat sink need the heat sink, because the microchip in the coil itself sporadically unloads the built up spark when the unit gets to hot as a self protective measure. That's "fine" for a stock truck, but that's not ok for high horsepower FI/N2O applications where you have increased dwell times, which means lot's of built up heat in the coil. Uncontrollable preignition = bad
Also, not being a dick, just trying to be informative, but nothing you said about the coils is actually correct. It's all internet hoopla. I had the LS2 truck coils on my car. The ones with the heat sink need the heat sink, because the microchip in the coil itself sporadically unloads the built up spark when the unit gets to hot as a self protective measure. That's "fine" for a stock truck, but that's not ok for high horsepower FI/N2O applications where you have increased dwell times, which means lot's of built up heat in the coil. Uncontrollable preignition = bad
11-01-2011, 05:57 PM
#32
Combustion temperatures with E85 are lower than gasoline because unit for unit, e85 has fewer BTUs than gasoline, and therefore burns cooler.
Also, not being a dick, just trying to be informative, but nothing you said about the coils is actually correct. It's all internet hoopla. I had the LS2 truck coils on my car. The ones with the heat sink need the heat sink, because the microchip in the coil itself sporadically unloads the built up spark when the unit gets to hot as a self protective measure. That's "fine" for a stock truck, but that's not ok for high horsepower FI/N2O applications where you have increased dwell times, which means lot's of built up heat in the coil. Uncontrollable preignition = bad
Also, not being a dick, just trying to be informative, but nothing you said about the coils is actually correct. It's all internet hoopla. I had the LS2 truck coils on my car. The ones with the heat sink need the heat sink, because the microchip in the coil itself sporadically unloads the built up spark when the unit gets to hot as a self protective measure. That's "fine" for a stock truck, but that's not ok for high horsepower FI/N2O applications where you have increased dwell times, which means lot's of built up heat in the coil. Uncontrollable preignition = bad
OK, no good for forced induction (increased dwell), but, is not hoopla. When a megasquirt is hooked up to a coil & strength of spark can be seen through RPM increases, it's not internet hoopla. I didn't know that the dwell time requirements were that much different in FI. So, for applications that require increased dwell times, heat sink type are not preferred. That doesn't rule out all LS1 truck coils. There are 2 types, one w/ & one without heat sinks. Each were better than stock LS1 coils when controlled using stock LS1 dwell times.
So, w/ new LS1 coils, is the curve now stable above 5400 RPM?
11-01-2011, 06:11 PM
#33
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I'm going to trust the builder/tuner of the worlds fastest drag radial car, who tuned my car, with real world first hand experience over internet "tests" and "hearsay". There's private party testings that disprove the truck coils superiority as well. Tests can be manipulated to show whatever results the tester wants to see (hot rod's 4.8/5.3 twin turbo build, for example)
Seat of the pants says yes
Seat of the pants says yes
11-02-2011, 08:33 AM
#34
That's cool. As with everything, we share our experiences & then weed out the stuff that doesn't fit. If there ends up being an issue w/ the LS1 coils, wanted to also mention LS3 coils. They are used in forced induction. Haven't seen the dwell time tables for LS3 coils, but, they are used in the SC vette. So, they may be another option if need be. There have been reports of stock LS1 coils failing when running increased dwell times.
Again, just talking here. Not trying to create an issue. The RX-7 is a great build & I hope that it provides a lifetime of enjoyment. The pics are awesome.
Again, just talking here. Not trying to create an issue. The RX-7 is a great build & I hope that it provides a lifetime of enjoyment. The pics are awesome.
11-03-2011, 06:27 PM
#35
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Badass. I like the bottom of the dyno graph "your **** is slow"
One suggestion though: only post a couple shots of the same angle of the car.
One suggestion though: only post a couple shots of the same angle of the car.
Last edited by HoLLo; 11-03-2011 at 06:32 PM.
