Boost v Temp v Timing v Power

**s4mmie** · 20-10-2012, 06:39 PM

Whats the relation?

I've started thinking about this with the onset of summer.. the poor little stock SMIC is feeling the summer heat.

I'm aware that the ECU can pull timing to stop detonation. Hotter intake charge temps would increase the chance of detonation, so the ECU would pull more timing on hotter days. Less timing = less power even with the same boost. So from what I gather, it's the combination of increased boost with more timing that equals better power.

Fitting a larger intercooler will reduce the intake charge temps considerably. I guess what I've been wondering is if I will see a considerable power gain by fitting the SEAT cooler? I'm running the stock SMIC at the moment and the intake temps are horrendous... if I'm correct, it has to be pulling a fair amount of timing. Fitting the SEAT cooler should lower the temps and give me my timing back.. more timing with the same boost should equal more power right?

Additionally, is a larger intercooler enough? I have been taking a hard look at water+meth injection to further cool the charge.

**clicht** · 20-10-2012, 08:54 PM

Originally Posted by spraycanmansam

I have been taking a hard look at water+meth injection to further cool the charge.

Do IT

**h100vw** · 21-10-2012, 11:18 AM

Originally Posted by spraycanmansam

Whats the relation?

I've started thinking about this with the onset of summer.. the poor little stock SMIC is feeling the summer heat.

I'm aware that the ECU can pull timing to stop detonation. Hotter intake charge temps would increase the chance of detonation, so the ECU would pull more timing on hotter days. Less timing = less power even with the same boost. So from what I gather, it's the combination of increased boost with more timing that equals better power.

Fitting a larger intercooler will reduce the intake charge temps considerably. I guess what I've been wondering is if I will see a considerable power gain by fitting the SEAT cooler? I'm running the stock SMIC at the moment and the intake temps are horrendous... if I'm correct, it has to be pulling a fair amount of timing. Fitting the SEAT cooler should lower the temps and give me my timing back.. more timing with the same boost should equal more power right?

Additionally, is a larger intercooler enough? I have been taking a hard look at water+meth injection to further cool the charge.

You would need to log the temps and pull to be sure whats going on.

Since I fitted my FMIC I have been watching the temp using Torque on my phone and a bluetooth OBD thing. Generally on the highway the intake temp is less than 10 degrees higher than the dash outside temp reading. On boost this drops to less than 5 degrees.

I am seeing the same boost on my gauge but I would have to check pre and post FMIC pressure to be sure that the turbo isn't working harder to maintain boost in the inlet, that could be dropped across the FMIC.

With a stage 1 tune, I would doubt that you will see much timing pulled, unless you get massive heat soak or put 95 in on the 98 program.

It would be true to say that performance won't drop off if you can maintain lower inlet temps.

WMI has been mentioned before and also that it is illegal. A proper kit would be up to $1000, Aquamist does one that I would consider myself. I'd run water alone to be half legal.... I'd use it to supplement intercooling, over mapping to take into account the "octane improvement" from meth. Gains would be less but it's safer if you run out.

Limited improvement for the cash involved is my thoughts.

Gavin

**noone** · 21-10-2012, 01:38 PM

As far as my Polo experience goes, the FMIC is not going to give you much over the stock FMIC in winter. In summer, you wont get back to winter power (as the hotter air is less dense), but atleast you keep much more power in summer.

Cant say much about w/meth

**s4mmie** · 21-10-2012, 03:12 PM

Hmm I have an eBay OBDII reader, I'll see if I can get some logs with that to better see what's going on.

I wasn't aware that water injection was illegal.. methanol is understandable.
In terms of Mr Plod, I would say they'd be less likely to pick up on a w/m setup than nicking you for an open pod filter..

USRT (Usually Sideways Rally Team) make a few kits and a nice throttle body spacer to run a nozzle post-TB. I have to look into it further but I think I would run a nozzle post intercooler and post-TB with a progressive controller.
I am thinking of running a large tank in the spare wheel well and keeping a bottle or two of distilled water in the boot in case of emergency.
I'll have to have a look at the Aquamist gear as well.
I agree, water injection is icing on the cake.

I guess I'll see what effect high temps and heatsoak have at Lakeside next weekend!

**h100vw** · 21-10-2012, 03:18 PM

Originally Posted by spraycanmansam

Hmm I have an eBay OBDII reader, I'll see if I can get some logs with that to better see what's going on.

I wasn't aware that water injection was illegal.. methanol is understandable.
In terms of Mr Plod, I would say they'd be less likely to pick up on a w/m setup than nicking you for an open pod filter..

USRT (Usually Sideways Rally Team) make a few kits and a nice throttle body spacer to run a nozzle post-TB. I have to look into it further but I think I would run a nozzle post intercooler and post-TB with a progressive controller.
I am thinking of running a large tank in the spare wheel well and keeping a bottle or two of distilled water in the boot in case of emergency.
I'll have to have a look at the Aquamist gear as well.
I agree, water injection is icing on the cake.

I guess I'll see what effect high temps and heatsoak have at Lakeside next weekend!

I have 2 VCDS leads and 2 laptops, so you can use one if you like. I plan to log mine too.

Gavin

**gavs** · 22-10-2012, 11:25 AM

Have you considered the cooling of the intercooler itself and insulating the pipe work? I know many many people ceramic coat and wrap exhausts to keep the heat in the pipe, not the engine bay but with heat soak occurring at standstill, wouldn't insulation of the pipe work be beneficial? In regards to cooling the intercooler, you could use a water sprayer or a CO2 spray setup which super chills the intercooler. One of my work colleagues used to pack his top mounted Subaru legacy intercooler in summer with ice when going down to Philip island and even though the ice would melt fairly quickly, he assures me that the gains of chilled charge air remained long after the ice was gone with a tangible decrease in fuel consumption.

**s4mmie** · 22-10-2012, 03:19 PM

Thanks, I might take you up on that for a few runs, it will be good to see what's going on.
At the Polo dyno day I was seeing almost 90 degree IAT's on a fairly cool day

Don't think I'll be pushing it too hard on the track..

gavs, I have

In particular the pipe that comes straight off the turbo over the exhaust manifold. I think that's where the most gains will be from ceramic coating and thermal wrapping. That's what I plan on doing anyway

Re the external intercooler cooling, the main issue I have read is the activation point. It would be easy enough to get a fairly crude setup going but it chews through the water big time. I found this a good read --
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I also like the C02 sprayers but you have to make sure the air intake doesn't get a gutfull.
I was looking at these options inc water injection and so far the water injection seems to be the best.

**gavs** · 22-10-2012, 03:52 PM

The CO2 sprayers are fitted to the outside of the cooler on the front (or top), like below....

Your biggest issue with the CO2 sprayers however is where do you put the CO2 bottle..... Also not exactly legal unless you have your vehicle placarded!