Mike O

For the one or two that might be interested, check out this..... Oh No! My page has been stolen! Its mostly a list supplemented by pictures. Enjoy!

thingo

Mike

Great to see such detailed info, have you had it on the track much? What compression ratio are you running?
What sort boost of advice did heritage give you?

Yours is a little more sensible than mine, very nice.

Mike O

At the moment, boost is at 1 bar. I expect to go to 1.5 After that, we will see. CR is 8.5:1.

I reckon the only thing that's sensible about this car is that it still has a radio and 2 tuner seats. The first time I scare myself at the track, we'll be looking a cage and full race seats.

No track time yet, we're still fiddling around with the fine tuning. Maybe by November.

PorscheDude1

Very cool.
Must run like a bat out of hell.

Nice touch with inconel heat shield.
Lots of nice details.

Enjoy!

Mike O

Absolutely!

Jason Lee (engines) and Jason Hiler (restoration) are the detail men. Left to their own devices this project would have been twice as nice. If only Warren Buffet had been picking up the tab!

JarmoL

Hi there,

For some reason the site won't open for me. Is the link still valid?
Great looking car with great specs!

Jarmo

ehall

Have you guys considered addressing the heat outlet of the exit air from the radiator and IC? That's a long air inlet pipe, so I was wondering about potential heat soak.
I get down to C. Florida every couple of months. I'd love to see your car in person! BEAUTIFUL!

Mike O

Jarmo,

Its working OK for me. I'm not the web guru so someone else will have to chime in.

ehall,

Let me know when you are in town. There's also the periodic GTG's that the 951 guys have for the locals. I hope to attend the next one. For the intake, the runner is long and its hot when you open the hood. The good news is that it is stainless so it has a poor heat transfer coefficient and the measured temps going into the throttle are around 113F on a 95 deg day at a little over 15 psi (114KPa) boost. I think that is acceptable. On the other hand, this is my first custom turbo, so feel free to educate me wherever I need help!

thingo

Was talking to my builder and a guy who works on wrc cars the other day about this, we are aiming for 10C above ambient, and they were saying it is above around 115 that performance is affected, so I would say you are doing fine there, particularly for such a neat solution.

Site works for me

A.Wayne

Great looking car , 15 psi = 200 kpa

ehall

My concern would be in two very different situations.
1. track On the track you will be running really hard, getting the radiator really hot, as well as the IC. Though the air gets rammed in the nose, our cars 951's and 968t's, don't really vent that hot air out of the under hood area very well. So that really hot air basically becomes convection. The performance loss, based on hot charge air, especially with the power that your car makes, wouldn't be my concern. My concern would become reduced knock threshold.
2. Stop and go traffic We live in the heat of the deep South. I doubt you'll get stuck in Orlando I4 traffic, in this car, BUT that tube is gonna get HOT behind that radiator.
Heat soak will definitely hurt boost, via less dense air charge, but your car should crack 550RWHP at less than 1.5 bar anyway.
However, what if you used a 968 TRS hood vent, or perhaps some vent slats to pull hot air out and away from the IC/radiator?

I was just thinking that you've already gone this far, why not look into this aspect.
HOWEVER, this is just an idea, and your car is sh%t hot just the way it is!
Here are a couple pics/ideas

Mike O

Thanks for the kudos guys , I'm begining to feel like the mother of a new baby!

When I speak of boost, I stick with Corky Bell's definition in Maximum Boost. Boost is the pressure above 1 atmosphere, also known a gauge pressure. 1 psi gauge = 6.89475728 KPa gauge so 15 psig = 103.4 KPa gauge.

Absolute pressure is measured gauge pressure plus atmospheric pressure and is the same as MAP or manifold absolute pressure. For MAP in a car running 15 psi of boost: 15 psi boost= Patm+15 psi boost= 14.7 + 15 = 29.7 psia = 204.8 KPa.

So, it depends on whether you are referring to boost or MAP. I was talking about boost. Does the 951 factory "boost" gauge actually measure MAP?

Ahhh! Engine compartment heat soak and ventilation. I totally missed the point. Jason and I did discuss installing two RS-like NACA inlets but I did not favor it at the time. For venting the engine compartment I'm thinking that a hood louver type vent located further back in a low pressure zone would be more likely to get that done effectively. Like the red 951 you show. I will be keeping an eye on the temperature and I really need some track time to see where the temps are headed before I commit to cutting the hood. An alternate thought is to remove the engine compartment to hood seal at the firewall. Has this been discussed or tried? Rejected as totally stupid?...

As it turns out, I now have 2 air temp sensors. The TEC MAT sensor and a Westberg sensor and gauge. I can relocate the Westberg sensor to measure engine compartment air and monitor it via the in-cockpit gauge. At least I'll have an idea of what the under hood temps are and if a little thing like removing the seal will have a noticeable effect. I'll just add that to my never ending list of things to do!

RolexNJ

How about a bump for updates on this Mike. I know we can go to the other site, but, can you share anything new?

Mike O

Will do, Rolex, just not tonight. I have to get my beauty sleep.

Mike O

Update:

I've been measuring the under hood temps. The sensor is mounted above the space between the radiator and engine so it is most sensitive to the temperature of the air flowing through the radiator. Heat rising off the headers only appears to effect this measurement when the car is stopped or moving slowly. As long as the car is moving 30 mph and up, the sensor is measuring about 150 F when the OAT is 75 F. Coolant temps remain normal (9 oclock or so). In traffic jams or stop and go city traffic it will get as high as 200 F. At the same time, coolat temps will approach 200-210 F. Running with or without the firewall to hood seal did not make a significant difference. Once the engine compartment gets heat soaked the temps won't come down until I can cruise at a sustained speed of at least 45. I believe venting the hood will be needed to make a significant difference. The header, crosssover, turbo, and downpipe heat needs someplace to go if you are going to drive like an inner city commuter!

I made it to Roebling Road in October. Everything appeared to be working just fine until a plug in the downpipe decided to unscrew itself. The car made funny noises so I went back to the paddock to diagnose WTF was going on. It turns out that the downpipe has two EGO bungs. My wideband sensor was still tight but the plug for the extra bung was MIA. Zotz Racing gave me an old EGO sensor and I was back in business after missing one session!

Beauty Shot:



In December I went back to the tuner. Here is the result with about 1 bar boost.



Driveability is good and power is improved but there are plenty of things to play with! I'll be back at Roebling Feb 21.

There is a little extra info in the 951 forum 3 Liter Turbo Registry post#16

P.S. - My provider (Roadrunner) made a system change which made my web page address invalid. I'll be working on that next!