Was up at Harry's Hot Rod Shop today looking for an adaptor for my BOV and wound up purchasing a couple of rolls of DEI "Cool Tape" insulating tape. I figured it was worth a try wrapping the new 4" Home Depot Motorsports and Racing Development Turbo Inlet Duct with it even though I was skeptical of it actually having any benefit. Turns out I was correct. Even though it dressed the ducting up a little bit, it doesn't seem to have added any effectiveness to the duct at all. Looks like 100% of the massive drops in IAT's is attributed to sticking the air filter back outside of the engine bay into an ambient environment. Today it was 57-60*F when I went out cruising. IAT's on the highway while cruising were 105-110*F so the same ~45*F different still seems to be a constant.





B

 

Have you tried wrapping the pressurized pipe from the turbo to the TB? I'll bet that is soaking up a lot of heat.

 

That would have some effect only if the temperature of the air inside the pressurized pipe is lower than the one on the engine bay. If not, it will be counterproductive I think. And judging by the temperatures some people get in their pipes after the turbo ( between 200 and 300 degrees) I would say it is pretty hard for the engine bay to get that hot. Maybe it does, I dont know.

 

Brian you could use one of those reverse vents that replaces the stock hood scoop to reduce the engine bay temps. I do like how your engine bay looks now.

 

Good points, but keep in mind he is cooling the charge air with Meth injection. So, with that in mind, it's possible that the pipe is conducting heat to the charge air.

 

That's exactly why I'm going to pursue coating the pipe and possibly wrapping it if the coating proves to no avail. I could care less what the charge temps are once they rise above engine bay temps in the hot air pipe. I just want to keep the charge temps in that pipe down during normal cruising and times of post-boost recovery to help reduce the load on the alcohol to drop them.

B

 

Personally it doesn't seem like wrapping the turbo outlet pipe would help too much. Even if it showed lower temps at the intake sensor. The air still has to travel through the UIM and LIM which are probably the hottest part of the whole intake being large chunks of aluminum bolted to the engine. Although I suppose if you could reduce the temps enough they would stay a little cooler as they enter the engine. I just have my doubts it would be enough to be effective.

But for the purpose of science and testing I say go for it.

 

That's the idea, Brent.

Just got back from RP. Ari welded up the aluminum flange for the blow-off valve. It's on. Going to put it all back together tomorrow and finally start doing some real tuning!

B

 

Just wondering, has anybody in the past ever got AIT readings from some place after the throttle body, like on the LIM right before it engines the engine? Would be interesting to see what those are, how big of a difference it is between your regular AIT and what the engine is seeing. If there is a 30-40 degree increase, maybe we could net some serious gains figuring out a better way to keep the UIM and LIM cool..

Just an idea, no clue how it could be done. I would love to do it, but I don't have an extra RE LIM.

(Maybe a thicker custom LIM gasket, and some sort of multi-layer, metal/fiberglass/metal/fiberglass/metal heat shield between the engine and the intakes to help keep the radiant heat from soaking into them?)

 

I used to use an IAT sensor located in the LIM next to the center iron housing in the primary intake port runner. It used to heat soak pretty badly.

B

 

I thought so too until I read Howard Coleman's post on meth injection. His UIM is literally frozen, too cold to touch due to his methanol injection.

 

I know it will be cooled during meth injection, my previous posts reflect that. But he wanted to wrap the pipe to cool the intake during off boost. During boost the turbo outlet temps would be higher then the engine bay so the wrap would do no good. Its the off boost when no meth is flowing that he wants to drop temps

 

BOV is welded on. Going tuning today if it warms up a bit. It's just above freezing here in DFW today. During my tuning today I plan on lowering the TurnOn point of the alcohol down from 8-9psi to about 2-4psi to help get the IAT's down earlier.

B

 

awsome, i think thats a good spot for bov as well.

 

Brian, how hard is it to adjust the "turn on point" for the AI, on the fly? I would do the exact same run at 2-4 psi, then again at 1psi. Just so you can see the difference that half second makes.

 

Yep it's on-the-fly. I've got it around the 2-4psi mark right now. If I turn it down further, I'll have to re-adjust the Gain ****. TurnOn is the starting point of the curve. The Gain **** adjusts the angle of it. So, to maintain the same volume of alcohol at 15psi I'll have to kick it down a hair bit (like I had to earlier today) if I move the TurnOn point back a bit.

B

 

did ya hit 20+ psi yesterday? Doooooo it!

 

Gimme a break Zack. I'll do it soon. I already hit 16-17psi yesterday but couldn't keep going. Got into too much traffic. Air temps held at 115*F. I'm adding 5% more alcohol at 15+psi to move it from a 70/30 ratio to 65/35. We'll see what happens. So far it's running really powerful. I'm also going to go ahead and put in one of the two new EGT gauges I've got so I can get some good 5V EGT probe readings to datalog. The IAT's are one thing; the EGT's are a whole other bag.

B

 

hahahaha i'm messin with ya buddy! just excited to really see what you can get out of the T70

 

I'd like to know myself. I'll probably mess around with it some again tomorrow. I've got a slightly modified map to load in. I'm also going to go ahead and put the one digital EGT I've got in and stick the new K probe in place of the broken one that's parked at the collector in the exh manifold. I really want some EGT numbers.

B

 

All of this playing around and after years of trying I still can't get Brian to play around with different intake manifolds!

 

Spent about an hr doing some tuning today. Didn't really have to do much in the form of fuel curve tuning on the Haltech. It was more getting the TurnOn and Gain settings on the alcohol system set so AFR's and EGT's would be good from 15+psi and above. I went ahead and removed 5% more at 15+psi on the fuel map and re-compensated w/ the Gain on the alcohol system to get it back in-line. AFR's are from 10.70's to mid 11's:1 at 15psi and above. EGT's are hovering between 1530*F to knocking on 1600*F's door pre-turbo. Today was the first time I was able to not only monitor EGT's via a new Digital EGT gauge but also log them via the Haltech's 5V spare A/D input.

Ambient temps today were high 70's*F. Cruising air temps w/o any load were about 115-125*F. I have alcohol trickling on at about 3psi of boost and progressively reaching 35% (for a 65/35 gasoline/alcohol ratio) at exactly 15psi.

The motor knocked hard twice in my 15-odd runs I did today. It knocked during one 3rd gear run and on my last, 4th gear run. It never did any other time. The only correlation I could find between both runs is the IAT's had reached 150*F. I initially was running about 16-15*BTDC Lead with an 8* Split but brought it down a degree on Lead and went to 9* Split. Didn't seem to make any change. The only thing I can think of that made it knock was pre-ignition of charge prior to timed spark event due to charge temp. Otherwise, all of the numbers are spot-on and it ought not be knocking. Without the two knock incidents, it ran very well and was quite powerful. I'm glad I swapped over to sequential leading ignition.

The next thing I'm going to try per a suggestion is to move the nozzles up-stream and stagger them by placing one very early up-stream and then the second one well later. As it stands now, they are directly facing each other only a few inches aft of the air temp sensor on the throttle body inlet adaptor. Perhaps I'm not leaving enough room or attacking it a certain way to get the charge temps down enough prior to the charge hitting the compression stroke. They may be way too close to the throttle. If anybody have any input on this point (time to flash, time for heat to be pulled via latent heat of evap, etc.), I'm all ears. I'm going to go ahead and give this one a shot instead of adding a small nozzle pre-turbo, first.

Attached in the next post are some screenshots of 5 runs. During these runs, I was modifying the TurnOn and Gain settings and it was having an effect on IAT's. BDCHA7 was a 3rd gear run that knocked. BDCHA11 was a 4th gear one that knocked. None of the other runs produced any knock. After the BDCHA7 run, I'd turned the alcohol up to run AFR's from mid 11's:1 to high 10's:1.

The photo below shows the location of the two nozzles in the hot-air pipe as well as the air temp sensor.

B

 

BDCHA7 - 3rd gear run, motor knocked











BDCHA8 - 4th gear run











BDCHA9 - 4th gear

 

BDCHA10 - 4th gear











BDCHA11 - 4th gear, motor knocked at end of boost run

 

BDC, aren't those IAtemps hot for full throttle runs??

This thread is epic, and I'm glad someone is doing this. Just as a curious observer to see what we (as a community) can learn.

In about a months time or so, my new revised vmount setup will be complete, and by than I figure you should have this system tuned well. My old vmount was poorly constructed, ducted, and ONE time it heatsoaked at idle. But I went back to the drawing board after I took it apart - because the errors I found in the system (I didn't build it) were so concerning. The important thing is I realized it was THAT particular setup and LEARNED to make it better. If you are coming to DGRR09 I would love to compare. I have a haltech e8 so I can datalog and post up as well, But mind you, our cars and systems are totally different. I'm trying to be as efficient as possible with no Auxinjection (to keep things simple). I'm a huge believer of air/air intercooler, and proper ducting/piping, and most importantly MATCHING.

What I mean by this is, matching your intercooler design to your engine and turbo setup, and often times on 7club I see people just upgrading power but not cooling, when it should be the other way around entirely. Most everyone in this thread seems to know what they are doing, so let us try to keep civil and see what we can all gain.



Another question back on topic, what injectors are you running? 550/1600? Why is your duty cycle so LOW at WOT. 30% average? Wouldn't running smaller injectors and a higher cycle mean more consistant spray? I'm a newbie to all this in retrospect to you all, so any advice is more than welcome.

thanks, Mikal