My 2.3l whipple after stage 1 SOS, AEM EMS and more

bruce91nsx said:
IATs during tuning in Tempe started at 110, spiked to 240 at redline then
immediately came back down. It gets hot but cools quickly. Again, I think
this shows the charger is at its efficiency limit.

I have the big-bore throttle body from SOS.
Click to expand...
I think the 13lbs alone could be causing the 240deg spike at which point you're maxing out the efficiency of the cooler. I know it's too much hassle, but i'd love to see what a 10lb pulley will spike at. In combination with your 2.3L and the slower spinning pulley you might have a SMMR track monster right there. It's the 240 spike that worries me. Though, I suppose if you modify your shift points to say below <7k rpm you'll still be plenty fast and not work up the IATs so high. You better take me for a ride next spring!

BTW did Shad or SOS mention what they thought the max efficiency of the cooler would be? I.e. at what boost levels or what SC rpm. I'm thinking some measure like 8-10lbs can keep your setup at around 180degs all day long (i'm just pulling #'s out of my butt.

BATMANs said:
How much does that big-bore throttle body from SOS help for a blower application?

I've heard that for a blower with a fixed boost it doesn't help. For NA and turbos it helps with the right set up.

Also I heard that meth injection kits doesn't work as well in positive displacement blower as opposed to BBSC and turbos.
Click to expand...
Meth isn't as efficient if placed pre-blower on any FI setup. The key on any setup is to spray post compressor. Unfortunately, for piggyback blowers the installation for that is much more challenging.

Edit: I'm hoping to see what a pre-blower meth injector will be like but ultimately i'm preparing to spray after the blower. DDozier had a project on building an injector plate that sandwiches where the intercooler does. The limits of a heat soaking meth kit installed this way is way higher than an intercooler but it's also got it's pros/cons :(
 
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RYU said:
BTW did Shad or SOS mention what they thought the max efficiency of the cooler would be? I.e. at what boost levels or what SC rpm. I'm thinking some measure like 8-10lbs can keep your setup at around 180degs all day long (i'm just pulling #'s out of my butt.
(
Click to expand...

I am thinking you are correct about the 10lbs...
We didn't talk about the max efficiency 'till after the dyno...
I had wanted a smaller pulley, but it got nixed for good reasons.

Edit to add:
It was 13 lbs at an altitude of 1,500 feet... I am at 5,300 feet here,
so I'm certain my boost and temps are lower.
 
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bruce91nsx said:
Edit to add:
It was 13 lbs at an altitude of 1,500 feet... I am at 5,300 feet here,
so I'm certain my boost and temps are lower.
Click to expand...
There you go! It's likely just perfect for where you live and probably where you drive the car most. Can I ask how you're tracking IATs? Is it via the factory temp sensor or did you pick up an AEM sensor?

Like Shad was saying in a previous thread. The 2.3L isn't for everyone but at slower rotations you're still pushing a considerable amount more of air than my 1.7L and cooler too. It requires more HP to push bigger rotors but seems worth it. I'm learning that at around 350hp the stock low boost CT Autorotor is sized perfectly. I probably wouldn't overdrive it with a "high boost" pulley since it already needs a heat soak solution :(. This thread was helpful. Thanks
 
RYU said:
There you go! It's likely just perfect for where you live and probably where you drive the car most. Can I ask how you're tracking IATs? Is it via the factory temp sensor or did you pick up an AEM sensor?

Like Shad was saying in a previous thread. The 2.3L isn't for everyone but at slower rotations you're still pushing a considerable amount more of air than my 1.7L and cooler too. It requires more HP to push bigger rotors but seems worth it. I'm learning that at around 350hp the stock low boost CT Autorotor is sized perfectly. I probably wouldn't overdrive it with a "high boost" pulley since it already needs a heat soak solution :(. This thread was helpful. Thanks
Click to expand...

Thanks!

They were watching the temps during the dyno runs...so am guessing it came off the AEM data.
 
BATMANs said:
i was under the impression that with forced induction the system will maintain the pre-set boost levels regardless of elevation that can support human life.

no?
Click to expand...

You're thinking of turbo or centrifugal superchargers, where there is a waistgate or such to regulate boost. With at positive-displacement (fixed-displacement) supercharger boost is generally a function of ambient pressure, RPM, and heat. There is a fixed amount of air compressed per revolution. You get what you get. This is why boost comes on instantly even at very low RPMs...once the system is closed/sealed, you're immediately at full boost.

What some people like Bruce (at least previously) will do at altitude is use a smaller pulley to get the supercharger RPM up to make up for thinner air...but then you can't go to lower altitudes without swapping back to a larger pulley.

Edited to add: Not having a wastegate or such to play with means it is more effort to turn up boost...which I think contributes to lower numbers of supercharger folks turning up the boost incrementally (I think the main cause of lower rate of engine failures).
 
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^^ What he said. Air is thinner just like how your GTO runs perceptibly better when it's cold outside.

At +5000ft alt a turbo compressor turbine has to and can spin the turbine shaft faster to achieve the same boost levels. Alternatively, (what latzke said) a belt driven compressor will always have a linear relationship to crank speed which makes altitude (air density) a variable. I suppose centrifugal SCs dont' perform this way too?

In any case, this is why a properly sized turbo is more efficient than any belt driven air compressor imo. You still don't really get that instant boost feeling with a turbo but man... the turbo technology these days are so impressive (e.g. 335i) that "lag" is almost unnoticeable. You also don't get parasitic drag on the crank either.

To go even further off-topic... I really wish Comptech built a turbo kit instead of a twin screw. It would be simply awesome to have a CARB legal turbo kit for the NSX.

I really like the variable vane turbo Mac_Attack is looking into...hope it works out for him. Sort of best of both worlds in concept.
 
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RYU said:
...... Air is thinner just like how your GTO runs perceptibly better when it's cold outside.....
Click to expand...

My GTO has so much silly power and a flat power band that at any temps I'm wrestling with trying to maintain traction 1-3 gears from a roll start.

And that's with 275/35/18 Dunlop Z1 in the back.
 
It would be great to see SOS or someone putting these SC kits together to redesign the intake manifold. They could copy mine or I could send drawings to have a casting made. My set up will hold a 1.7, 2.3 or 2.9L blower and has a off the shelf Fluidyne heat exchanger. They offer about 3 units that will bolt in place and sell for around 500.00. The other benefits are relocating all the bottom mount connection including the by pass tube to the sides so you have easy access to everything. The biggest advantage to me is being able to get the IC-SC under the factory engine hatch or Targa cover. I have no problems at 17- 19 PSI with heat. Ken
 
ken sampson said:
It would be great to see SOS or someone putting these SC kits together to redesign the intake manifold. They could copy mine or I could send drawings to have a casting made. My set up will hold a 1.7, 2.3 or 2.9L blower and has a off the shelf Fluidyne heat exchanger. They offer about 3 units that will bolt in place and sell for around 500.00. The other benefits are relocating all the bottom mount connection including the by pass tube to the sides so you have easy access to everything. The biggest advantage to me is being able to get the IC-SC under the factory engine hatch or Targa cover. I have no problems at 17- 19 PSI with heat. Ken
Click to expand...
+1

I would consider a cost effective AND efficient IC solution. Nice to hear your positive comments on the IC Ken. Time to find your build thread again!
 
Good news....just passed emissions!!!

Can't thank the SOS crew for all the great mods AND keeping me within the emissions laws here in Colorado... I described only a tiny bit of the mods SOS did in this thread...

I have such a fun all around car now... one weekend I was consistently running 12s in the quarter mile (at 5,000 feet altitude, subtract about a second for sea level), the next weekend I won a 1st place car show award in the import car division at the annual CU Sports Car Club car show, which had 320 entries this year.... then I passed emissions...

soon, now back to my road tracking days all summer...

and helping to organize NSXPO 2012! ...watch for complete details soon on the Web... i can promise you all an awesome time in Colorado! Personally... I can't wait!

cheers,
--bruce
 
Congratulations Bruce!

Tha is one of the cleanest and well thought out supercharger installs I have seen! And the numbers reflect this.

Well done!
 
Very nice build! About how much did it cost?
 

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