Hi everyone!

I'm still sorting this turbo ITR out. It wasn't running all that great this last weekend, but still faster than most everyone but a couple of H2 cars (I had a passenger handicap, but still Ed Sackley was pulling very similar straightaway speeds...)

Anyhow, running at low (8 psi) boost, not making ALL that much power, oil temps were high. 295-300F or so, Mobil1 15w50, GReddy oil cooler and C&R Radiator. I don't know if it was any higher, my Defi temp gauge only goes to 300. I don't know if it keeps spinning past the end of its range or if the stepper motor just stops there.

Before the motor rebuild to 9:1 pistons and eagle rods: The stock motor with slightly more power would usually see oil temps around 260-265, never past 270. My EGT's are also a couple hundred degrees higher, 1850 instead of 1650. I'm starting to believe it needs more timing, because the A/F is 11.5:1 when warm, and richer when hot.

So,

What makes oil temperature higher? Cylinder temps? Bearing doing work? I heat-wrapped the downpipe where it crosses under the oil pan, that didn't help at all. I'm probably going to heat-wrap the whole manifold and exhaust to keep under-hood temps lower.

I've lost a few chunks of dipstick rubber grommet into the oil pan, I wonder if one is gumming something important up? I don't think so. The oil lines to/from the oil cooler are scorching hot.

Hmm!

RR98ITR Scott, who I had the pleasure of meeting, suggested placing some masking tape over the oil temperature gauge. Alternately, ditching the A/C condenser or getting a ricer wide-mouth bumper might help get some air through the intercooler/oil cooler/condenser/radiator.

Thoughts, feedback welcome. Be sure to remind me how dumb I am to HPDE a turbo car and expect it to stay in one piece.
-Chris

 

Hmm .. bigger oil cooler?

Are you still running 91 octane pump gas? At 11.5:1 A/F, I'm sure your cylinders are getting pretty hot. 100+ octane race fuel or av gas would probably keep the cyl walls a little cooler. You could also tune to run a little cooler (richer), but you'll sacrifice power. Is your oil cooler right in the air stream (i.e. in front of the radiator/intercooler)? If not, maybe you could duct air to it somehow to improve heat transfer.

I think I'm out of suggestions. HTH

- Scott, who doesn't have an oil temp gauge because he doesn't want to know

 

Do you have an intercooler on it? If so, you have: intercooler, AC condensor, radiator, and oil cooler all trying to get some of the air going in the bumper openings. Do you still have the factory oil squirters? If yes, that is one of the major heat sources. If your EGT are running that high, the combustion chambers are in fact getting rather hot. Much of the extra heat is being pulled out of the pistons via the oil squirters.

Get the tuning right, spend the time and money on the dyno to get it right, then look at how the temps are running. You may need a bigger oil cooler or some sort of ducting. Consider an air dam/splitter setup. It keeps air from going under the car and may increase what is available for cooling. Consider some sort of air extractor vents in the hood to let the hot air out faster. Vents over where the turbo is may also help hot air get out better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">Are you still running 91 octane pump gas? At 11.5:1 A/F, I'm sure your cylinders are getting pretty hot. 100+ octane race fuel or av gas would probably keep the cyl walls a little cooler. </TD></TR></TABLE>

Why would higher octane gas cool the cylinder walls better?

 

I remember reading in Corky Bell's book "Maximum Boost" that a larger turbo, and higher compression will both lead to less heat. Which turbo are you running right now?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FlyZlow &raquo;</TD></TR><TR><TD CLASS="quote">Are you still running 91 octane pump gas? </TD></TR></TABLE>

It's tuned rich and on 93 octane gas with Hondata. Suprdave pulled some timing and added extra fuel to keep it "safe". I run either 93 octane with 20% toluene added, or about half/half 93 and 100 octane. It runs the same either way, even up to about 100% 100 octane, maybe a little less power.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mohudsolo &raquo;</TD></TR><TR><TD CLASS="quote">Do you have an intercooler on it? If so, you have: intercooler, AC condensor, radiator, and oil cooler all trying to get some of the air going in the bumper openings. Do you still have the factory oil squirters? If yes, that is one of the major heat sources. If your EGT are running that high, the combustion chambers are in fact getting rather hot. Much of the extra heat is being pulled out of the pistons via the oil squirters.</TD></TR></TABLE>

Yeah, it's Intercooler-&gt;Oil Cooler-&gt;Condenser-&gt;Radiator. Yes the stock squirters are in place. Would you suggest I REMOVE them to keep oil temps down, and let the coolant suck up that heat? Coolant temps are fine so far...

I've spent the money to dyno and street tune it right, a couple of times now. I'm going to give it another shot though, I agree.

 

all motor

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EK4civichatch &raquo;</TD></TR><TR><TD CLASS="quote">I remember reading in Corky Bell's book "Maximum Boost" that a larger turbo, and higher compression will both lead to less heat. Which turbo are you running right now?</TD></TR></TABLE>

GT2871R, small turbo. Low compression too, 9:1. But at the same time, low boost, 8 PSI. I can't imagine it's making much more than 220-230 WHP on a dynojet at that power. 12 PSI is close to 320 WHP on a dynojet, but after coming off of a track I stuck it on high boost and plopped it on a Mustang dyno, and only had 239 on high boost, running visibly (sooty) rich.

-Chris

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">Be sure to remind me how dumb I am to HPDE a turbo car and expect it to stay in one piece.
-Chris</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dan GSR &raquo;</TD></TR><TR><TD CLASS="quote">all motor </TD></TR></TABLE>
:middlefinger: Thanks Dan.

 

Where is your temp sensor placed?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">Where is your temp sensor placed?</TD></TR></TABLE>

Sandwich plate under the filter, right next to the oil pressure sensor, along with two oil cooler lines.

-Chris

 

did you have the same defi guages before the rebuild?

 

Do you have a bigger oil pan? I'm thinking something in the 6.5-7qt range will help.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dan GSR &raquo;</TD></TR><TR><TD CLASS="quote">did you have the same defi guages before the rebuild?</TD></TR></TABLE>

Same gauges, same locations, same cooler, same oil, nothing changed outside the motor and turbo. *shrug*

I'm considering running THINNER oil to get more flow through the cooler.

Oil pan is stock, unbaffled. A bigger one might slow down the heating... I think a bigger oil cooler would be in store first.

 

Water/alchohol injection?

 

I think keeping the squirters is a good idea, they probably keep the piston temps down some and reduce the likelyhood of detonation. More oil volume will help. Getting air directly to the cooler will help a bunch, as will a larger cooler. You should be well within the efficiency range of that turbo and 9:1 is reasonable. I think airflow management is the way to be looking.

My guess is that either there is poor airflow where the cooler is now or the air getting to it is already too hot. I'm guessing you don't have access to a full size wind tunnel to check it out either. A couple of remote temp sensors with a readout in the car would allow you to find out how hot it is in different areas at speed. I think the oil cooler really needs to be out front, getting the best possible airflow. How big is the intercooler, could it be too big? By too big I mean blocking airflow to the other coolers and having more cooling capacity than is needed. I really do think vents in the hood to release hot air could help a lot too.

 

A lot of heat comes from the valve train. Bend a paper clip back and forth a few times and feel the heat...now think about 16 valve springs working their butts off while the bottom end is turning @ 8,700 rpms. Those cam cover plates are full of oiling holes for lube and cooling. VTEC pistons are oil cooled, so the oil has to absorb that too...along with all the friction generated at the bearings etc. Now you have a turbo (oil cooled I assume) and you are making 120+ hp more than stock, and more HP = more heat. You need the big cooler, 25 - 30 rows that gets good air flow, -10 lines and all the capacity you can muster (bigger pan, bigger filter, etc). No matter what, you may be limited to 30 minute track sessions.

I'm making about 180whp. I use a 25 row, -10 lines, HP-1 sized filter and my temps stay under 250. Before installing my cooler I'd hit 300.


Modified by Track rat at 6:52 PM 5/31/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Track rat &raquo;</TD></TR><TR><TD CLASS="quote">A lot of heat comes from the valve train. Bend a paper clip back and forth a few times and feel the heat...now think about 16 valve springs working their butts off while the bottom end is turning @ 8,700 rpms. Those cam cover plates are full of oiling holes for lube and cooling. VTEC pistons are oil cooled, so the oil has to absorb that too...along with all the friction generated at the bearings etc. Now you have a turbo (oil cooled I assume) and you are making 120+ hp more than stock, and more HP = more heat. You need the big cooler, 25 - 30 rows that gets good air flow, -10 lines and all the capacity you can muster (bigger pan, bigger filter, etc). No matter what, you may be limited to 30 minute track sessions.

I'm making about 180whp. I use a 25 row, -10 lines, HP-1 sized filter and my temps stay under 250. Before installing my cooler I'd hit 300.


Modified by Track rat at 6:52 PM 5/31/2005</TD></TR></TABLE>

I'm glad to see I'm not the only one at 300F.

I will probably take out the A/C, which should help. Plus heat coat and wrap the entire exhaust in the engine bay. Plus, get the dump tube recirculated back into the exhaust. I'll consider a ricer hood next, then a bigger oil cooler.

 

How comparable are temps taken in the oil pan versus those by the oil filter. I'd think they'd be pretty comparable(within a few degrees really).

I have an SR20DET, and I run about 10-11 psi on the stock T25 at HPDEs. I have a baffled GReddy pan(which is badass, aluminum, baffles, +1 QT capacity, and lots of fins). I have a Defi oil temp gauge in the side of the pan(underneath the oil level definitely, it's right by the drain bolt). I run about 245*F oil temps on my SR at the very end of a session, it was about 75-80*F at the time, and this is with NO oil cooler. Water temps were 205*F in the upper radiator hose(stock thermo=176*F). I have an upgraded Koyo radiator. I think the Al oil pan is really helping keep the temps down on the oil, since it can probably dissipate quick a bit of heat energy with ~3-4 ft^2 of area. Not as good as a good sized oil cooler, but it's providing some cooling.

I was getting slightly concerned with the 245*F oil temp, but I think it's well within the range of Mobil1 15W-50.

Now, with the stock sidemount intercooler, I was running 190*F water temps(no FMIC to block flow) and 205-210*F oil temps. So it does make a difference if you block airflow to the radiator.

Are you also watercooling your GT2871R? That might take some load off your oil cooler.


My plan is to build a splitter and put some ducting/block off plates around the side of the radiator and underneath it. Basically making sure that any air that's going in the radiator opening pretty much has to go through the radiator. I've thought about throwing in an oil cooler, but if I can keep the temps below about 250-260*F I'm not all that worried about it.

I suggest you look into building some ducting for your oil cooler and radiator. The air will take the path of least resistance, so if you just have the oil cooler hanging out in the open it won't be getting much flow at all since air will just go around the core instead of through it for the most part. Same with your radiator. I can give you some basic pointers on how to make a good duct on the inlet and outlet of the core if you want.

BTW, I'll trade you turbos for $100! The T25 will bolt right up!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote">Sandwich plate under the filter, right next to the oil pressure sensor, along with two oil cooler lines.

-Chris</TD></TR></TABLE>

I'm assuming it measures the temp before the cooler, right? I'd start with a larger cooler and make sure the lines you run are sufficiently large. I wouldn't run a larger oil pan.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">

I'm assuming it measures the temp before the cooler, right? I'd start with a larger cooler and make sure the lines you run are sufficiently large. I wouldn't run a larger oil pan.</TD></TR></TABLE>

I'm going to see if I can get the most from my current setup. AC is coming out first. I'm also going to run slightly thinner oil which seemed to run cooler too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by El Pollo Diablo &raquo;</TD></TR><TR><TD CLASS="quote">Why would higher octane gas cool the cylinder walls better?</TD></TR></TABLE>

I had read that higher octane fuel burns more slowly and has better cooling properties which is why it's better for higher compression ratio motors. My impression was that you run higher octane fuels to avoid hot spots on the cylinder walls, which can cause detonation if enough heat builds up. Perhaps this is incorrect? Feel free to straighten me out ... I'm no expert by any means on this stuff and we all know there's as much misinformation as information to be had on the internet.

- Scott

 

Higher octane burns SLOWER, and is harder to ignite. So, if there is a hot spot, it is less likely to preignite high octane gas.

That's my understanding.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris F &raquo;</TD></TR><TR><TD CLASS="quote"> My EGT's are also a couple hundred degrees higher, 1850 instead of 1650. I'm starting to believe it needs more timing, because the A/F is 11.5:1 when warm, and richer when hot.</TD></TR></TABLE>

EGT's of 1850, that thing is a hand grenade and the pin has been pulled. Turbo must be red hot, it might be heating the oil.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Def &raquo;</TD></TR><TR><TD CLASS="quote"> I think the Al oil pan is really helping keep the temps down on the oil, since it can probably dissipate quick a bit of heat energy with ~3-4 ft^2 of area. Not as good as a good sized oil cooler, but it's providing some cooling.</TD></TR></TABLE>
I know this is kinda an odd suggestion but has anyone tried putting finned heat sinks onto the sides/back/front of their oil pan? You can get computer heat sinks for pretty damn cheap that'd add quite a bit of surface area to the pan in an effort to help disapate heat...

Christian