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Oil temps way high after header install

18K views 118 replies 15 participants last post by  brapp 
#1 ·
Recently installed a set of Killer B headers on my car. I love them, but I'm a bit concerned about the increase in oil temps I've been seeing.

Before, the car would usually run around 180-200f around town and go up to 220f max on spirited drives through the mountains -- maybe creeping towards 230 if it was a really hot day or I was really pushing it. Track use would usually see temps maxing out around 250f.

Now though... I'm seeing 220 often around town (in the winter) and just yesterday hit 240 driving slowly up a mountain pass in a snowstorm. Keep in mind.. this was constant 3200 rpm, 30ish mph, no boost, outside temp was about 30f.

I'm wondering if the headers proximity to the oil filter is heating the oil significantly -- or, if the sensor in the drain plug is being overly heated from the outside.

I'm not too concerned about the 240f temp by itself... but the fact that I'm hitting that when it's below freezing out and the car isn't seeing any boost makes me pretty worried for 90f track days this summer...
 
#11 · (Edited)
I could see that for sure. But the jump seems really drastic, which is why I'm concerned.

Any ideas of how to shield the sensor?

raisingAnarchy said:
I'm assuming you're tuned. Are the headers coated or just bare?

I've been having trouble with putting the temp sensor in the pan's drain plug location. I think most sensor/thermocouples aren't designed well enough to mitigate ambient temps. I just don't know where else to put it because in theory it really is the best spot.
Yes, tuned for the mods.

Headers are bare... which I could see being a part of it.

Lots of horror stories around here from folks who have sent their parts to Swaintech... mixed with having the car down for 2 months to get the headers back make me not really want to go that route and local coaters just offer a basic coating that probably won't do a whole lot.

I've been considering wrapping them, but there's lots of people telling me that's a poor idea as well.

In the end, I asked around and heard from many (including Killer B) that running them bare wouldn't really affect performance much, so that's what I've been doing so far.

SubySal said:
Hey Danny,

This is my set up. I don't have any issues with false oil temp readings as far as I can tell. With the undertray winter temps peak at about 180ºF. Time Attack temps peak at 230ºF and track temps at 245ºF. Because I'm me I also throw a wrap of DEI gold tape around the oil filter.
Thanks Sal. I was actually thinking to wrap the filter and maybe the pan in gold tape to try to help the situation a bit. I wonder how much the bigger oil pan helps too. Do you have your oil temp sensor in the drain plug?

8cd03gro said:
Did you remove the undertray as part of the header install?
Still running the plastic undertray. It melted in one tiny spot... maybe size of a quarter. I have a Beatrush one on order but they are backordered 4-6 weeks.
 
#3 ·
I'm assuming you're tuned. Are the headers coated or just bare?

I've been having trouble with putting the temp sensor in the pan's drain plug location. I think most sensor/thermocouples aren't designed well enough to mitigate ambient temps. I just don't know where else to put it because in theory it really is the best spot.
 
#10 ·
Hey Danny,

This is my set up. I don't have any issues with false oil temp readings as far as I can tell. With the undertray winter temps peak at about 180ºF. Time Attack temps peak at 230ºF and track temps at 245ºF. Because I'm me I also throw a wrap of DEI gold tape around the oil filter.

Image Link
A little off topic, but can you share details on how you've insulated your oil temp sensor? Are you using the sender that came with the Perrin gauge? Is that a metal conduit covering the wire/sensor from the chassis up to the pan itself?

I read through your build thread on this topic again, but didn't find some of these details.
 
#7 ·
That could be. I know there's a lot of aero on the '06. I just use the plastic OEM undertray. I haven't had any melting issues in the 5 years I've been racing the car even with ambient temps over 100º at the track. I just put some DEI gold tape on the tray where it was close to the header.
 
#12 ·
How to wrap your header/uppipe - NASIOC


I wrapped my Killer B just like Unabomber above when I installed it about 13 months ago and it's been great (you do have to put some foil paper however on the wrap near the oil filter during oil changes).


My oil temps in South Florida have been +5 or 10 degrees increase or so vs. stock manifold with heat shields even with the wrap (my oil temp sensor is in the oil pan).
 
#13 ·
I am pretty sure I'm going to do the same. I've been a bit wary of wrap mostly as I live in Colorado and the car gets driven all year in all seasons. So it does see a lot of moisture and I don't want to rust out or crack the headers. But it seems like a lot of folks have been running wrapped for a long time with no issues so I'm leaning towards doing that.
 
#16 ·
You'd be surprised how little header and header proximity effects oil temps. Many years ago (before we made headers) we had a road coarse track guy who had a set of F-R headers that made contact with our pan. Not just a little contact, but primary contact along a +6" surface ON the pan. He had no overheating issues. NOT what I'd ever recommend, but it certainly showed how little the header effects the areas around it. If you you look at flow, volume, surface area, etc. a worse case scenario and you're exposing <2% to higher temps.

I would check your sender connections/ground. If they were disturbed during the header install that could effect the temp reading on the gauge.

What else changed when the header was changed? Oil change? Tune? Fuel type?
 
#19 · (Edited)
Interesting. The intake was changed from an SPT to a Grimmspeed along with the headers and the car was retuned for those changes.

I am starting to wonder about the sensor. It's a Defi sensor in the pan using a Killer B drain plug adaptor. The part of the sensor that is exposed to the air around the headers (not the actual sensing part, more where you would tighten it into the plug) is metal and is open to the air. I could definitely see how it could be getting heated and cause an elevated reading -- though I'd imagine it would be insulated against something like that.

killerbmotorsport said:
As far as wrap goes, we no longer warranty headers that are wrapped. This was a change we made a few years ago after seeing some failures due to wrap induced corrosion. In short, wrap in-use under daily driving conditions causes rapid oxidation (corrosion) of the base metal. Ideally headers used for daily driving are either left bare, or coated. If you want a coating that performs on the same level as a high performance wrap (and have the time and budget, as it's a long and expensive process), I recommend a product we use; Swain Tech Multi-Layer Ceramic Coating.
The one nice thing about CO is that they don't salt the roads here. So while it would be exposed to wet conditions (or as much as the undertray lets through), it wouldn't be getting covered in salt. Even so... sounding like you wouldn't recommend a wrap?

I'm sure Swaintech has a great product... and if I had gotten the headers straight from you I would've opted for that option. I got an amazing deal on them from a vendor though, so I bought them bare. It's not so much the cost for Swaintech that has me shying away... it's the huge downtime for the car and especially how many folks on here have had problems with receiving their headers back in poor shape or with overspray issues they had to clean up later.

As an aside... your website says both that you can wrap (and keep the warranty) and also that you do not warranty wrapped headers. Might want to remove the first mention :)
 
#18 ·
^ I don't see why not. I typically take a piece of tin foil over the header and remove the filter.

As far as wrap goes, we no longer warranty headers that are wrapped. This was a change we made a few years ago after seeing some failures due to wrap induced corrosion. In short, wrap in-use under daily driving conditions causes rapid oxidation (corrosion) of the base metal. Ideally headers used for daily driving are either left bare, or coated. If you want a coating that performs on the same level as a high performance wrap (and have the time and budget, as it's a long and expensive process), I recommend a product we use; Swain Tech Multi-Layer Ceramic Coating.
 
#25 ·
Update...

Got some Fire Sleeve... covered the sender and about half the exposed gauge wire in it. Then wrapped the rest of the wire in gold heat tape. No change unfortunately. So, while the gauge itself could be wonky... the heat isn't affecting the reading.

I'm kinda doubting the gauge is off as it wasn't touched during the header install and immediately started showing higher temps after the headers were on.

I also got some of DEI's new oil filter heatshields, so I'm going to try that next and see if that has any measurable benefit.

Also thinking to try to pick up a Killer B oil pan here soon... mostly for the extra oil capacity on track, but also thinking it'll help with oil temps some.
 
#26 ·
Update...

Got some Fire Sleeve... covered the sender and about half the exposed gauge wire in it. Then wrapped the rest of the wire in gold heat tape. No change unfortunately. So, while the gauge itself could be wonky... the heat isn't affecting the reading.

I'm kinda doubting the gauge is off as it wasn't touched during the header install and immediately started showing higher temps after the headers were on.

Although that may be a good reason to not jump to the conclusion that the gauge/sensor has gone bad, I wouldn't rule it out. Unfortunately, I'm not sure how to diagnose that deterministicly without spare parts to swap in.
 
#34 ·
So normal AFR.

You have to start with something you know is good and work from there.
I'd start with the sensor. If bad, all this is moot.
 
#40 ·
Danny, it might be easier to use an IR thermometer to test the sensor in place instead of messing with boiling water and such.

I ran the road course at PPIR a couple years ago and my temps peaked at 245ºF with the Killer B pan, baffle, pickup. That was with my old gauges, but as far as I know the oil temp at least was accurate. I do think the pan is totally worth it even for the time attack series. The track has way more grip than your typical autocross surface and the corners are generally longer. My temps there peak at about 225-230ºF.
 
#41 ·
Would the IR thermometer work though with the sensor actually inside the pan? I'm imagining the exterior part of the sensor would be a lower temp.

That's another thing that had me thinking about the pan. I've heard from Gladu and a few others that well-prepped STU cars can be in the danger zone even just on an autocross course. I usually do 8-10 autocross days per year, most of the time attacks, and a good 5-6 track days on top of that. I'd say probably 20+ motorsport type events per season.
 
#42 ·
The oil and pan should be very close in temperature. If the sensor is brass it too should be the same temp as the oil. Rubber's an insulator and even so with tires if you don't get a probe in right away the temps are quick to equalize. It might be a few degrees difference, but shouldn't be way off especially if the car is stopped and no air is flowing over the pan or sensor.

I personally think the stock oiling is good for nothing beyond some spirited driving. So yea fast driver's can drive past stock oiling capabilities on an autocross course. Chris had the Killer B pan on this last engine. The engine failed because of some new screwy octane rules that had just been implemented in ST and he was trying to stay legal. That led to detonation and it lunched #4 I think.

The engine before that however was lost to oil starvation. I believe it happened at Spring Nats a few years ago. He said there was a pretty long sweeper and that did it in. I think he had a Killer B pick up, but didn't have the pan at that point because it was not yet legal in STU. Since installing the Killer B pan Spring Nats hasn't been an issue. Though I haven't asked if there were corners similar to the one that gave him trouble before.
 
#46 · (Edited)
The oil and pan should be very close in temperature. If the sensor is brass it too should be the same temp as the oil. Rubber's an insulator and even so with tires if you don't get a probe in right away the temps are quick to equalize. It might be a few degrees difference, but shouldn't be way off especially if the car is stopped and no air is flowing over the pan or sensor.
Thats a good point for the thermometer. I think I'll give that a try. Been wanting one of those anyways for tires... good excuse I guess :lol:

killerbmotorsport said:
Well, not really. The oil control valve actuates ~1.45Gs. On the street you're not going to see this unless you're running a fairly non-street-legal setup. Oil doesn't start to push out the breather ports until ~1.6Gs (track/conditions dependent). So in short, if you had the OCV on a street car it just wouldn't activate ever. So in my opinion you'd be better off spending that money on more worthwhile mods.

We have them installed on several track dedicated race cars with documented +1.8Gs sustained, and all the issues with pushing oil out the breather ports has gone away with the OCV in place. This is really the environment they were designed and intended for.
Gotcha... so if I'm reading you right, the valve helps with a different G-force related oil starvation issue than the pan. I was thinking they accomplished the same task in different ways. But I suppose the pan helps with keeping enough oil at the oil pickup? If the OCV is to keep oil from getting pushed out the breather ports... yeah that seems a bit extreme.

Leemanfor said:
Brapp, do you go to HPR?
Only made it out there for the first time last year for a Track Night in America event. Loved it though... definitely planning on going there a few times this year. Most of my track days have been at La Junta or at WHP/Bondurant down in Phoenix.

HPR mid-summer was actually when I really realized I needed to start with cooling and reliability mods with the car. I was running in the advanced group and could only really go about 10 minutes before I had to back off and take some cooldown laps to let brakes and coolant cool back down. Oil wasn't at the point of backing off yet, but was sitting right at 250 at that point as well. And that was an evening event with like 75 degree temps too.
 
#47 ·
I'm not an engineer, but I play one on TV. :wave:

Dan, The IR thermometer will work, but it's not the best way to track tire temps. A tire pyrometer works much better, but even with that you almost need someone right off the course ready to stick your tires to get accurate temps. By the time you get back to grid they will have already started to equalize.
 
#49 ·
So, update. I'm starting to run out of thoughts at this point.

I've wrapped the sensor wire in Fire Shield and DEI Heat Tape, I've wrapped the oil filter in DEI's new oil filter heat wrap. Added Killer B pan and Beatrush undertray (both primarily for reasons other than oil temps, but both should help). I used a high end IR thermometer with help from Harvey at The Boost Creep, it reads the temperature right at the sensor as within 5-8 degrees of what the sensor is reading.

I tried a track day. Went to La Junta Raceway... a pretty small track that I've never had any sort of cooling issues before. I hit 260 oil temps within 3-4 hot laps... which was under 5 minutes of going at full pace.

The next day was a local track's Time Attack series. It's more or less a large autocross run by connecting different infield sections together with cones. Laps were right about 60 seconds in 2nd and 3rd gear. Two back-to-back runs with a couple minute cooldown in between got the oil up over 250.

So... I'm kinda at a loss. According to everyone on this thread, the headers shouldn't be causing the oil to get hot. But I'm pretty much completely out of ideas other than that.
 
#52 ·
But I'm pretty much completely out of ideas other than that.
If it's been covered I opologize, but what radiator are you running?

You can put the gold heat reflective foil on the pan surface facing the header and coating the header with Swain Tech or wrap would provide benefit as well. I don't think either of those will have a measurable impact, but at this point, you're running out of things to try.
 
#61 ·
"Racing" is expensive.

This is where I harp on people about building a car for cooling. For track, cooling should be a HUGE focus if you want it to last. That is why my S2000 is setup the way it is.

It’s impossible to run straight 20mins even on a stock car. Those that do it aren’t monitoring.
I could melt down a stock car pretty quickly. I've ridden passenger in some stock cars with novices and even they were overheating their cars.
 
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