140 replies to this topic

[Jim Drago]

PS: We both know it is the rare 1.6 that has not already optimized the header, so maybe a net 3 HP gain for $20. That's cool.

While I understand what you are saying. I think it is VERY important to realize there is a very real difference in an 'optimized " header that is meant to pass tech versus one that is fully legal to be ground on. I would guess that the gain will be 1.5 -2 x greater than optimized.

[ner88]

anyone doing the $20 manifold porting please let me know, I'll send you a few cars to do! Just sayin!

[dmq]

does anyone know if nasa is considering these changes for the 1.6?

[Derrick Ambrose]

does anyone know if nasa is considering these changes for the 1.6?

See Post #52

[38bfast]

Stop that frank it will leave a mark.

[B(Kuch)Kucera45]

From our testing we saw roughly 40 degrees drop in intake air temperature by removing the turn signal assembly. Basically it takes and makes the intake air equal to ambient plus 2ish. The theory is that colder intake air temp equals more HP. I think the rumor is like 1hp for every 10-12 degrees of reduction, but I'm not a motor guy so I will defer to someone who is. I can say that at a couple different tracks we saw roughly 2mph increase on all straight aways long or short, so it appears the car was getting off the corner better.

On the header grind, we saw no gain until 6K when it was like 1.4 and then at 7k it was like 1.6 both HP and TQ. This was an engine dyno, not a chassis dyno.

Sean

Thanks for sharing but I can understand the manifold grinding and how that will affect hp and TQ but I'm confused about the turn signal removal part. Yes the manifold could gain up to 1-2 hp and TQ on higher rpm and this will help on the top end but it doesn't help down low. My thought is that this isn't going to help us where we need it. Now I might be totally wrong about this but that's what I'm trying to get cleared up.

As far as the turn signal being removed I can understand how this will help with the heat soak problem but cant see how this is adding any power because it's not a ram air system. So an ambient temp 1.6 would be at its max power possible. So my thought on this would be no added hp or TQ from this only help maintain ambient temps.

Can you guys please clear this up for me if I'm thinking about this all wrong.

Again I'm thankful for the smac for giving the 1.6 something this year.

[38bfast]

Kuch everything tested and tried did not incress torque without increasing HP. It just a fundamental problem of a lower displacement engines not just the Miata, Yes there are ways to get it done but are way out of the scope and cost of SM. The only to get the torque in a 1.6 is to put in a 1.8. But then again due to the lack of torque of the 1.6 is why it enjoys being the lightest car in the class. Just to see how much that affects your car stap 125lbs in it the next time you go out to the track. You will come in and say "well that was no fun at all. The car is a complete turd"


The turn signal change has nothing to do with ram air. It's all about lowering the intake charge tempature. Lower charge tempatures increases the density of the air thus being able to add more fuel resulting in more heat / power / energy. Yes it does cure a lot of the heat soak issue but the benefit also can be seen on lap 1. The NB cars draw air from the LF wheel well. The NA cars are drawing air from under hood area.

Look on your Dyno sheets and look at the correction factor on a hot summer day vs cold ass winter day. No ram affect at all just tempature change.

Or when on track in the hot summer days you can go to gas much sooner because the car is just not putting out the power. But when it's cold if you go to gas at the same point the car can't hold the track.

Another example is you see all the big charge coolers on the boosted cars. It's all about reducing charge tempature creating a higher density of O2.


In my plane the affect of air temp is extremely evident. On hot summer days I eat up much more runway trying to get in the air. In the dead of winter the plane uses much less runway to get up in the air. Same goes with the rate of climb. When its cold as hell the thing loves to climb out but in the hot of summer its "I sure hope I can clear those trees". Almost like two completely different engines.

Or closer to home for you. On your 250 two smoke dirt bike. How much more jet do you have to add when you go ice racing? Colder air, now you need more fuel to match.

[Bench Racer]

Theory is that for each unit of 10* F reduction in air temp a 1% (some say more than 1%) power increase is gained. With ambient air intake and a wrapped snorkel from AFM to throttle body presume you are two (20*) to four (40*) temperature units cooler than you currently are. That would be a 2% to 4% power gain. My thermocouple numbers showed it's worth the few bucks and time to implement.

 

Search for or call Mark Bennett. 

[B(Kuch)Kucera45]

Thanks Ralph but I understand all of that. My thought behind it is your only keeping it at ambient temp and when your on a dyno your setting it at ambient temp (air/fuel). It's not like a drag car that is running a fuel cooler on it.

So let's say when I set my air fuel and timing for an 80% day and I go out on the track and it's 80% out. Your saying I'm going to get more hp or TQ out of it. Is this correct ?

Because my thought was the turn signal is only going to help with heat soak issues keep the air temp down. Now if we where allowed to add a set up like the NB cars that would be diff. Like you said they pull air from the left front wheel well area and has a slight cone to the air box.

Am I correct ?

Now be nice I'm just asking to wrap my head around this ! Thanks

[B(Kuch)Kucera45]

Theory is that for each unit of 10* F reduction in air temp a 1% (some say more than 1%) power increase is gained. With ambient air intake and a wrapped snorkel from AFM to throttle body presume you are two (20*) to four (40*) temperature units cooler than you currently are. That would be a 2% to 4% power gain. My thermocouple numbers showed it's worth the few bucks and time to implement.
 
Search for or call Mark Bennett.

Cool so your saying no more waisting time at the dyno because we removed the turn signal bulb and this will keep it cooler and give us more power ! It will be a set and go now saving us money for more races.

[38bfast]

If you car is set for 80 and you go on track you are actually seeing 120 to the engine. So you are losing power. With the turn signal removed your engine will see close to 80. No loss of power.

Another thing just to prove the point. Next time you are on the Dyno take a pull with hood up and then take a pull with the hood down. About the same thing happens on track.

Some have tried the hood up on track but that has not seemed to work out well.

[B(Kuch)Kucera45]

If you car is set for 80 and you go on track you are actually seeing 120 to the engine. So you are losing power. With the turn signal removed your engine will see close to 80. No loss of power.
Another thing just to prove the point. Next time you are on the Dyno take a pull with hood up and then take a pull with the hood down. About the same thing happens on track.
Some have tried the hood up on track but that has not seemed to work out well.

Ok now I got it ! Duh

[38bfast]

Cool so your saying no more waisting time at the dyno because we removed the turn signal bulb and this will keep it cooler and give us more power ! It will be a set and go now saving us money for more races.

Sorry no. Tune it on the Dyno. Log AF on the Dyno. Take it to the track and compre your Dyno AF to track AF and ajust to match at the track. We do this with all the years.

[38bfast]

anyone doing the $20 manifold porting please let me know, I'll send you a few cars to do! Just sayin!

$20 intake tube wrap unless your Bench and fell compelled to spend $200

[Bench Racer]

$20 intake tube wrap unless your Bench and fell compelled to spend $200

Ok, you forced me to find the receipt.

 

Heat Barrier       $35.99

Spray Adhesive $17.29

Tax                      $2.72

Total​                  $56.00

 

Labor, it's a PITA

[Bruce Wilson]

more power, absolutely... but a hunch tells me that if some folks had an abnormal heat soak problem before, this will not solve it, but only make it slightly better.  I hope to be proven wrong.

[mhiggins10]

I didn't see this officially cleared up- since this is the prelim Fastrack, are these changes effective in December or do we need to write another letter?

 

And thank you to the SMAC for getting this through.  There are lots of 1.6 owners like me who are happy to take what we can get, and won't complain that it's not enough until we run several races and really see the impact.  I especially appreciate you guys finding low cost solutions!

[Bench Racer]

I didn't see this officially cleared up- since this is the prelim Fastrack, are these changes effective in December or do we need to write another letter?

Open for input to the CRB. I'll write another letter confirming it's a positive step for the 1.6.

[mhiggins10]

Open for input to the CRB. I'll write another letter confirming it's a positive step for the 1.6.

Just sent my letter of support.

[Mike Babcock]

Big THANKS to the SMAC for devoting so much time and energy to this!  I think the recommendations were absolutely appropriate and adequate to bring the 1.6 back into contention, without making it COTY, and at a minimal cost.  Seriously... well done!