2007 Exige S Intercooler Air Flow Study

[apk919]

Originally Posted by charliex

i think the problem with the start/stop traffic is the sheer amount of heat coming from the engine/headers.

I'd like to do a little more investigation of the following graph (the graphed temp is of the ducted air after passing through the I/C, not charge temp):



It doesn't look like there was a lot of heat soak at the intercooler from standing still (there are a few segments in the data where I was waiting at a light for at least 30 seconds), and the largest increase in temperature was during high load periods... but as soon as the car's speed got to around 30-40mph (unloaded) the temps went back down. I'd like to correlate that to charge temps when I get a chance...

[charliex]

as expected, the most load generates the most heat but it has less airflow, higher speed, less load, more airflow.

then the IC temp drops way off on decel since there's no load, so less heat being generated and lots of airflow.

so if you're on track you're probably in the worst area, high load, medium speed, medium airflow.

i'd like to see a graph that measured how long it takes for the IC to heatsoak, then how long it takes to cool off, if it can, so sustained high load, medium speed, til the temps max out.

next time i'm at the track i'll try to do something along those lines.

there is going to be a point where the efficiency maxes out and thats where we ought to be looking at, but a few degrees isn't going to do a whole lot, removing the rear panel dropped temps for us by about 20 degrees.

[apk919]

Originally Posted by charliex

as expected, the most load generates the most heat but it has less airflow, higher speed, less load, more airflow.

then the IC temp drops way off on decel since there's no load, so less heat being generated and lots of airflow.

so if you're on track you're probably in the worst area, high load, medium speed, medium airflow.

i'd like to see a graph that measured how long it takes for the IC to heatsoak, then how long it takes to cool off, if it can, so sustained high load, medium speed, til the temps max out.

next time i'm at the track i'll try to do something along those lines.

there is going to be a point where the efficiency maxes out and thats where we ought to be looking at, but a few degrees isn't going to do a whole lot, removing the rear panel dropped temps for us by about 20 degrees.

I'd like to try removing the rear panel and increasing the size of the side intakes (either without the mesh or with larger gauge mesh... I know Frank's already done this), and fabbing up an aluminum heat shield that would go between the I/C and the top of the engine... I also need to straighten out my data acquisition equipment for OBD-II parameters... as long as the Innovate module is interrupting my tach and speedo (and possibly the warning lights) I don't want to take the car out on the track that way...

[charliex]

Is it using the CAN line instead (2008 car? ) , yeah that'll be why its interferring with the cluster.

[robains]

When sitting in my garage making tuning adjustments (10-15 minutes at idle and/or some rpm hits) charge temps goes up to about 121 F. Same thing happens when driving in LA traffic -- goes up to 121.

It seems to cool down extremely rapidly with higher speeds. Going over the grape vine, I was trying to generate some heat going up with no success. In fact, in 6th gear over 100 mph I think I may have to make a tune adjustment as it really keeps the charge temps very low. At larger tracks like Thunderhill 3.19 mi long straight where one hits 130-135 or so or like Fontana 150-160 or so I don't think heat soak could ever become an issue (at least with the RLS anyway).

Probably end up tuning for each track I go to next year.

Rob.

[ZJChaser]

Originally Posted by robains

At larger tracks like Thunderhill 3.19 mi long straight where one hits 130-135 or so or like Fontana 150-160 or so I don't think heat soak could ever become an issue (at least with the RLS anyway).

Probably end up tuning for each track I go to next year.

Rob.

Keep dreaming that one. Both on expected speeds at Fontana and temps . I hit 138mph at Fontana and saw charge temps post IC of 190 on a nice cool 75 degree day. I know you'll be better with a larger pulley but still... I'd love to see my temps in the 120-130 top range

I dont know why people keep compairing a few pulls on the freeway to a track session. THey are soooo far different situations that they cant be compaired. I cant get my air temps over 300(from the blower on the street) but it happens plenty on the track

[Monsi]

Originally Posted by apk919

I have to wait until I get my Christmas present first: Failed 2nd Gear Synchro - Warranty Claim Approved (was denied)

[apk919]

Originally Posted by charliex

Is it using the CAN line instead (2008 car? ) , yeah that'll be why its interferring with the cluster.

My car has the stock '07 ECU (but possibly not for long ), the Innovate OT-1 is plugged into the OBD-II port and is supposed to automatically select the correct protocol... that's not to say it's not doing something silly on the CAN line... I've called them and posted on their forum and have gotten no good answers... Mag's '08 S240 has no issues with the same setup

[apk919]

Originally Posted by apk919

I have to wait until I get my Christmas present first: Failed 2nd Gear Synchro - Warranty Claim Approved (was denied)

Originally Posted by Monsi

You're telling me! It failed before my first two track days... I had to double clutch all my 3-2 downshifts...

[robains]

It was a little more than just a freeway pull 1 hour of stop and go LA freeway followed by a long long long pull up the grape vine at WOT -- I'm sure you've gone up the grape vine (it's not a short quick hill). But if you take a look at percent of track time actually on throttle it's not as massively different. But I agree you're not creating tranny heat, brake heat, etc. etc. -- tracks are different and my point was each track will be different.

If I had hit 150 at Fontana in a Mustang Cobra with worse aero and worse HP/Weight then I'd expect to at least do the same in my Lotus (I hope).

Rob.

[apk919]

Originally Posted by robains

...
If I had hit 150 at Fontana in a Mustang Cobra with worse aero and worse HP/Weight then I'd expect to at least do the same in my Lotus (I hope).

...

Top speed is not about HP/weight... it's about HP/effective frontal area...

And the Lotus doesn't have a very good HP/effective frontal area ratio...

EDIT: effective frontal area = Cd * actual frontal cross sectional area

[charliex]

Originally Posted by apk919

My car has the stock '07 ECU (but possibly not for long ), the Innovate OT-1 is plugged into the OBD-II port and is supposed to automatically select the correct protocol... that's not to say it's not doing something silly on the CAN line... I've called them and posted on their forum and have gotten no good answers... Mag's '08 S240 has no issues with the same setup

if its a 2007 car then try disconnecting the can lines on the OBD II port if the innovate has wiring on them, it should not interfere with the cluster if its purely K line.

[ZJChaser]

Originally Posted by robains

It was a little more than just a freeway pull 1 hour of stop and go LA freeway followed by a long long long pull up the grape vine at WOT -- I'm sure you've gone up the grape vine (it's not a short quick hill). But if you take a look at percent of track time actually on throttle it's not as massively different. But I agree you're not creating tranny heat, brake heat, etc. etc. -- tracks are different and my point was each track will be different.

If I had hit 150 at Fontana in a Mustang Cobra with worse aero and worse HP/Weight then I'd expect to at least do the same in my Lotus (I hope).

Rob.

my indicated speed was over 150 but my data logger told me otherwise. I'm pretty sure with a better run onto te oval and staying in it deeper I could hit 145 but then we are running out of gearing, developing load of intake heat, and just running out of steam on the top end. I'm sure once I get the air temp charge down significantly it will be a lot better.

[apk919]

Originally Posted by charliex

if its a 2007 car then try disconnecting the can lines on the OBD II port if the innovate has wiring on them, it should not interfere with the cluster if its purely K line.

Thx Charlie... I'll give it a try!

[robains]

1999 Mustang Cobra is a moving brick, it'll never be as efficient as anything Lotus. At the time the Cobra was running around 331 wHP but did have a good track gearing. But totally agree, need to get it out on the track and see.

But so far the following appears to help considerably with engine bay temps and air charge temps:

1. Opened mail slot
2. Sealed IC Shroud
3. RLS IC
4. Bumper removal with VonHep
5. Heat wrap exhaust pipe from header to muffler

For track I plan to drop in a ceramic coated no-Cat pipe.

[shay2nak]

Finally fettled da mail slot today and cut down the bottom edge of the thick gasket. Amazing to see the difference. The rear passenger bolt was a bitch to tighten. Was easy to remove it...WTF.

Originally Posted by robains

But so far the following appears to help considerably with engine bay temps and air charge temps:

1. Opened mail slot
2. Sealed IC Shroud
3. RLS IC
4. Bumper removal with VonHep
5. Heat wrap exhaust pipe from header to muffler

For track I plan to drop in a ceramic coated no-Cat pipe.

don't forget about...

6. Remove the grill from each side intake.

[qball]

What passenger bolt? You mean for the hard top?

7. Install two puller fans on the intercooler...

[shay2nak]

Originally Posted by qball

What passenger bolt? You mean for the hard top?

yeah, the bolt for the hardtop right behind the passenger seat.

[apk919]

Originally Posted by charliex

if its a 2007 car then try disconnecting the can lines on the OBD II port if the innovate has wiring on them, it should not interfere with the cluster if its purely K line.

Originally Posted by apk919

Thx Charlie... I'll give it a try!

I disconnected the wiring from OBD-II pin 14 (CAN data low) internally in the Innovate module... that seems to have solved the problem... I'm getting no cluster abnormalities while logging data.

Awesome suggestion Charlie!

[ericwgexige]

apk...the aluminum heat shield between the top of the engine and the IC...I was thinking the same thing. It would have to be of some help. Also, if one could fabricate another shroud on the engine side if the IC and duct the air directly outside...maybe with a puller fan or two to help it along...