Spec Boxster Build

[thstone]

Originally Posted by Topless

Eeeeesh! That sucks the joy out of racing. Sorry Tom.

I do think "plan B" is wise though. When a motor grenades it stresses, wears, and deforms in unexpected ways and shiny bits get into everything, everywhere. A sound used motor with clean oil is not a 100% sure thing but probably a lot more certain than one that has been a metallic sausage grinder. I went through this in an earlier life with both a 350 Chevy and Ford 351 motors.

Best wishes for 2015 my friend!

Thanks and yes, my thinking is that it was time to start over with an engine with only street use and no previous metal processing! I am hoping that this engine will last as long as my previous stock engine.

[jaykay]

Originally Posted by thstone

The engine had an EBS sump baffle but otherwise is stock. No Accusump. But I am seriously looking at options.

Wow that hurts. Three in one season is just crazy! Any over revs? What was did different about your previous engine/car? Diff. tires and tracks?

I never really understood the EBS baffle's specific value other than being metal and the incorp. of the small baffle sections....I guess I would have to get my hands there to see how it fits up. There is no reserve oil volume and it would appear oil can still "climb" the baffle walls. I would think a trapped volume oil via a windage tray (horizontal baffle and vert. baffles would be the way to go with a deep sump as big as your ground clearance goes...then Accusump? Anyway there a few good sumps on the market now.

Ahh I know a guy....think he looses an engine a season (M97)chasing mustangs and camaros....high revs then boom

[thstone]

The more I learn, the less I know.

It seems that the only way to be sure of maintaining oil pressure (to the largest extent) is to use an EPC-based Accusump system. Anything less will leave open a window of uncertainty. Baffles, windage trays, deep sumps, etc. are all steps in the right direction but they don't seem to guarantee what an Accusump can.

The other concern not yet mentioned in this discussion is oil temp and film strength. It appears to be critical to never let the oil get too hot. Thus, I am looking into a data logging system that can provide temp alerts and possibly an external oil cooler.

I'll have to continue researching these subjects. Right now, not exactly sure what to do.

[seningen]

Originally Posted by thstone

The more I learn, the less I know.

It seems that the only way to be sure of maintaining oil pressure (to the largest extent) is to use an EPC-based Accusump system. Anything less will leave open a window of uncertainty. Baffles, windage trays, deep sumps, etc. are all steps in the right direction but they don't seem to guarantee what an Accusump can.

The other concern not yet mentioned in this discussion is oil temp and film strength. It appears to be critical to never let the oil get too hot. Thus, I am looking into a data logging system that can provide temp alerts and possibly an external oil cooler.

I'll have to continue researching these subjects. Right now, not exactly sure what to do.

I lost a 944 engine within accusump

We've been lucky since adding an oil cooler and running amsoil.

Is that the key? I don't know.

My next plan for my boxster s is an oil cooler and low temp
Thermostat.

Not sure I'll go all the way to an accusump.

Mike

[thstone]

Originally Posted by seningen

I lost a 944 engine within accusump

We've been lucky since adding an oil cooler and running amsoil.

Is that the key? I don't know.

My next plan for my boxster s is an oil cooler and low temp
Thermostat.

Not sure I'll go all the way to an accusump.

Mike

Thanks for the input Mike! My car already has a low temp t-stat. I am also looking at oil coolers and saw your post in the Spec Boxster area on Rennlist. Let me know if you learn something that doesn't get posted.

[steved0x]

I'm going to be the one to show my ignorance and ask: can you add the 3rd center radiator? Would that help keep things cooler, including the oil?

[thstone]

Originally Posted by steved0x

I'm going to be the one to show my ignorance and ask: can you add the 3rd center radiator? Would that help keep things cooler, including the oil?

That is a perfectly good question!

I have a few thoughts on the center (3rd) radiator;

One, I worry that using the coolant to lower the oil temps is hugely inefficient. Seems like direct oil cooling would be best. But you bring up a really good point.

Second, the 3rd radiator adds weight that would need to be removed somewhere else. Ok, so remove some weight somewhere else - I hear you.

Third, in my experience the 3rd radiator may not be enough. On days when the coolant temps in my car were getting too high, the same was happening to the cars with the 3rd radiator. So I wonder if the 3rd radiator is really worth the weight and expense. This one is a little harder to sort out.

Thanks for the input and I will certainly re-look at the 3rd radiator as I sort this out...

[steved0x]

What about a dedicated oil cooler in the 3rd radiator spot? Or do you lose too much pressure with a long run like that? I seem like I remember reading folks have a hard time adding oil coolers due to space constraints?

[thstone]

Originally Posted by steved0x

What about a dedicated oil cooler in the 3rd radiator spot? Or do you lose too much pressure with a long run like that? I seem like I remember reading folks have a hard time adding oil coolers due to space constraints?

Exactly right; the worry about running an external cooler in the front is the pressure loss over that distance. I am looking to see what might mount in the rear to keep the distance minimized.

[seningen]

Originally Posted by thstone

Thanks for the input Mike! My car already has a low temp t-stat. I am also looking at oil coolers and saw your post in the Spec Boxster area on Rennlist. Let me know if you learn something that doesn't get posted.

Need to see if I can find it again, but I saw a nice looking setup
Where they ran an accusump and remote oil filter in the trunk and
Two coolers in the rear bumper area, one for oil and one for tranny.

Not that I want more weight in the back...

I wouldn't run the oil cooler up front, although
That is what my RSR does, but 911s are used to pushing oil to the dry sump
And it does help with weight distribution.

My S already has the 3rd radiator.

I've seen a setup that deletes the oil/water radiator on top of the block and takes the oil from there for circulation, however I think most take it off the filter housing.

I'll look for the pictures of that setup.
I had sent a q about a turnkey system but got no response.

I'm also considering a forced air setup in the triangle
In the bracing are near tranny, but not in love with oil cooling near exhaust
But that maybe no different than rear bumper

FOUND IT --- to me this looks like a pretty sweet setup.

http://www.dartauto.com/projects/2013/8/20/spec-boxster-accusump-and-transmission-oil-cooler/


Mike

[Topless]

RE: oil cooler setup

Have a look a McDuff's ext. cooler in the rear trunk. It may be overkill but data on temps and pressures looked really good at Chuckie last month in 95F ambient. I was pretty impressed with his results. Not sure if his setup meets current BSR rules though.

Meanwhile another accusump-equipped car developed rod knock. Accusump looks like it is batting about 220 so far this season.

[stephen wilson]

I think a Accusump quickly runs out of oil under sustained cornering/oil starvation. Isn't the best solution (and the most money) still adding a scavange pump to the other cylinder bank, in addition to a deep baffled sump and extended pickup ? A water/oil heat exchanger would also be a great idea.

[seningen]

Originally Posted by stephen wilson

I think a Accusump quickly runs out of oil under sustained cornering/oil starvation. Isn't the best solution (and the most money) still adding a scavange pump to the other cylinder bank, in addition to a deep baffled sump and extended pickup ? A water/oil heat exchanger would also be a great idea.

What is the pumping rate of the oil pump? Accusump typically has 3 qts under
about 60psi.

I wonder if the pickup sucks air -- which drops the pressure -- but now you
are shipping around aerated oil as well as your pressure drop?

I wonder if there is something to temperature, aeration, and oil starvation
that comes into play at the same time.

Mike

[cmacduff]

Gents- my $.02 cents for what it's worth.

As topless mentioned I had an external oil cooler added to the rear trunk of my car ( capacity and efficiency of the cooler was conveyed to me to be 4x the efficacy of the stock S cooler) I had motec data analysis before and after the addition of the cooler. Additionally I had some oil pan baffle mods done by Dwain at Vision Motorsports and have before and after data. My oil temps before the cooler in the warmer weather were topping 250 degrees and engine temps were topping 210. Usually toward the mid to end of a 20 minute session. Additionally I was having oil pressure issues in a few corners at WSIR and AA speedway. With the addition of the cooler, oil pan mods I was running 25-30 degrees cooler in back to back events in September at WSIR and ambient temps were pretty similar. Additionally oil pressures improved quite a bit. My engine temps never topped 195 degrees where previously they had topped 210. I have all the data to support these changes and conclusions. I've had the oil tested twice also since these changes and it came back clean. This also included a day on the AA speedway roval. As Topless mentioned data from CVR where it was pretty warm again was really good.

I like Tom have been through a motor in the last year so we'll see how this one holds up with these mods. Initial signs look good.

[seningen]

Originally Posted by cmacduff

Gents- my $.02 cents for what it's worth.

As topless mentioned I had an external oil cooler added to the rear trunk of my car ( capacity and efficiency of the cooler was conveyed to me to be 4x the efficacy of the stock S cooler) I had motec data analysis before and after the addition of the cooler. Additionally I had some oil pan baffle mods done by Dwain at Vision Motorsports and have before and after data. My oil temps before the cooler in the warmer weather were topping 250 degrees and engine temps were topping 210. Usually toward the mid to end of a 20 minute session. Additionally I was having oil pressure issues in a few corners at WSIR and AA speedway. With the addition of the cooler, oil pan mods I was running 25-30 degrees cooler in back to back events in September at WSIR and ambient temps were pretty similar. Additionally oil pressures improved quite a bit. My engine temps never topped 195 degrees where previously they had topped 210. I have all the data to support these changes and conclusions. I've had the oil tested twice also since these changes and it came back clean. This also included a day on the AA speedway roval. As Topless mentioned data from CVR where it was pretty warm again was really good.

I like Tom have been through a motor in the last year so we'll see how this one holds up with these mods. Initial signs look good.

This supports what I have found holds our 944 engine together in Chumps.
Before adding an oil cooler -- we went through several engines. Accusump didn't matter.

Do you have pictures of your installation? Do you have a build sheet we might be able to mimic?

thanks,

Mike

[cmacduff]

I knew that was going to be the next question....

Give me a few days and I will get some good pics of the cooler and the specs off the invoice. I think the most compelling thing was the oil pressure differences and my gut tells me that is the baffle mods that were done. I just had a stock EBS baffle and I was having pressure problems in a few corners at WSIR and then after the baffle mods and oil cooler they were gone. Pressures before got in to the mid to high teens in the problem corners and then I never got below 30-35 in the same places. I know that you have to be really careful and also analyze if I was on or off the throttle at those times also when making that determination. When I overlaid laps from before and after the pressure problem I had no less than 4000 RPM's in those same corners. Of particular note I have also learned it is important to know where those temperature readings are coming from and also where the pressure is read. I had an extra sensor installed and it reads these temps/pressures from the main bearing. It is my understanding that the stock sensor reads them from the oil pan.

That being said...I am by no means a Motec expert and am still a rookie in this hobby/sport and learning every day/time on the track. There are many others on this forum that know WAY more than I ever will. These are just my "rookie" findings. I know there are a ton of variables and nobody has the exact answer to this problem.

I want everyone to know I'm not an expert or claim to be one. Just want to share what I have learned about this issue thus far. I was fortunate to have a data system in the car before and after to make these comparisons.

I will follow up with some pictures and the specs on the oil cooler shortly.

[seningen]

Originally Posted by cmacduff

I knew that was going to be the next question....

Give me a few days and I will get some good pics of the cooler and the specs off the invoice. I think the most compelling thing was the oil pressure differences and my gut tells me that is the baffle mods that were done. I just had a stock EBS baffle

Clarification -- I'm running the EBS baffle -- just wondering what you mean by stock EBS? I also have a 0.5qt deeper sump with a pickup extension.

thanks,

Mike

[jsceash]

I'm not a spec driver But have been using an accusump setup deep sump and stainless windage baffles for almost 3 seasons, Mine is a 2 quart tank. I have data on 2 oil pressure point. One at the tank and the other at the port on the bank 1 head where the pressure switch normally mounts. I do not see pressure below 70 on the tank and 60 on the motor while on track. I am seeing 240-250 degree oil temps. I'm interested in additional oil cooling above the S engine mount cooler.

[seningen]

Originally Posted by jsceash

I'm not a spec driver But have been using an accusump setup deep sump and stainless windage baffles for almost 3 seasons, Mine is a 2 quart tank. I have data on 2 oil pressure point. One at the tank and the other at the port on the bank 1 head where the pressure switch normally mounts. I do not see pressure below 70 on the tank and 60 on the motor while on track. I am seeing 240-250 degree oil temps. I'm interested in additional oil cooling above the S engine mount cooler.

Just curious to see what your post track idle pressures are? I've seen mine drop below 15psi...

I snapped my temp sender post (ugh!!! and I am reordering a sender) so I don't have temp values yet).

Mike

[thstone]

Originally Posted by Topless

RE: oil cooler setup

Have a look a McDuff's ext. cooler in the rear trunk. It may be overkill but data on temps and pressures looked really good at Chuckie last month in 95F ambient. I was pretty impressed with his results. Not sure if his setup meets current BSR rules though.

Meanwhile another accusump-equipped car developed rod knock. Accusump looks like it is batting about 220 so far this season.

Yes, I've seen Chris's trunk mounted cooler. That thing blows like a ... uh, tornado. Unfortunately, not legal for BSR/SPB.