Stijn!!

[RKDinOKC]

Have had 3 different kinds of Porsches.
944 Turbo, BoxsterS, and 928GT'
These three cars with their different weights and peak HP amazingly enough had the same 0-60 times, 5.4 seconds. But that 0-60 time felt very different in each car.

The 951's hp curve starts low and increased significantly as rpm increased.
This made the 951 accelerate faster as you increased rpm. It kept pushing you back in the seat harder as rpm increased. Making it feel the fastest.

The Boxster started out higher in hp, but did not increase as much as the Turbo as rpm increased. As rpm increase you got used to the acceleration rate and while it felt faster as rpm increased it did not keep pushing you back into the seat as rpm increased.

The 928 hp curve, due to the dual plenum intake is almost perfectly flat. It has more power at low rpms, but does not increase much as rpms increase. The acceleration rate stays the same from low rpm thru high rpm. Once you change gears because the acceleration rate stays the same it feels like it accelerates slower as the rpms increase. Making it FEEL the slowest of the three even though their 0-60 times are the same.

The upgrades I made to the GTS each increased the power band, cams, headers, x-pipe, tuning. They were not peak or low-end, but raised the entire curve. While not getting the crazy peak hp of cars like the Hellcat, It increase the low end enough to make it a bit touchy on initial acceleration. That is why I mentioned when accelerating from 0 to over 25. Like when merging from a stop to 45mph traffic. Below 25 you can eaily accelerate without crossing too much into the power curve. I'm sure that going to injectors that are a little bigger will help smooth out that instant on transition.

[RKDinOKC]

Yep, one of the first things I did when made supervisor of the drafting/engineering department was put a vent hood on that blue-line copier. You turn on the blue-line, it turned on the vent fan. It really really helped. But the blue line copies themselves stinked too.

Was glad to see the darkroom with all it's chemicals go as well. The B/W offset press plate burner was the last thing to need the darkroom. When the per copy prices finally went down on B/W from the color laser press it was finally all digital.

[RKDinOKC]

When I first moved into the drafting department we kept all our drawings and the blue line machine in it's own room and kept the door closed.

Remember this one time a sales person brought his cat in to take to the vet later that day to have it put down. It had feline lukemia. The guy came in at 6:30 and put that cat in the drawing room. We did not discover it until we came in at 8. That cat had spread diarrhea all over the place. Man, the drafting supervisor (glad it wasn't me) was pissed! Made him take the stinking (literally) cat and put it in a box in his own office. It wasn't very long until his boss told him to get rid of the cat.

My boss made him clean the room 3 times before the stink was gone.

Can't imagine what possessed a person to do that. The room we kept all the production drawings etc. It was even locked, but that idiots master key let him in. We changed the lock!

[GH85Carrera]

I worked in a professional photolab with all the photo chemicals from 1971 until we shut it down and went all digital 2004 or so so well over 30 years. Anyone that remembers the old days of the x-ray department and the smell of the fixer is familiar with that "aroma" and the developers and other chemicals were not real pleasant, but I was around it so much I really did not notice unless I was mixing chemicals of working on the opened up processor.

More than a few customers came in and would ask how we could stand the smell, and I always said, what smell.

We had one employee that just hated the stink of the processor, when he was standing in total darkness feeding photo paper onto the feed table. The bleach-fix was not pleasant, but not horrid. They called OSHA and filed a complaint. So out comes OSHA and we had to shut the production down so we could turn on the lights. She spun a little gizmo around and found just a trace of amonia, and it was like 1/50th of the limit. That employee was fired soon after.

[flipper35]

The power band in the Cobra is flat other than below 1800 rpm. I think it is the overlap in the cam. Once you hit 1800 it is pulling hard and is really flat. Now I have to put the oil temp monitor in the new road race pan and try that out. I hate losing oil pressure because the g forces have removed the oil from the sump. Now I just need to baffle the fuel cell. If I am under 1/3rd tank and run hard I will run the floats dry by the top of third gear.

[GH85Carrera]

The El Camino is far from a powerhouse. Base 350 with cast iron manifolds. It has lots of low end torque, but it gets breathless pretty soon under full throttle above 2,200 RPM. Leaving a stoplight it is great up to 45. If I floor it on dry pavement I can get a little tire spin, but mostly it just goes. No doubt a throttle body fuel injection system I cobbled together from the V6 setup is part of the issue. Back when I wanted to convert, the options were very limited, as no real commercial system on the market. So I found a guy that sells the V6 FI system, with a chip programmed for the stock 305. It starts and runs and never hesitates. It will start up instantly when it is zero or 110 with a hot engine or stone cold engine. It runs like car is supposed to, and is exponentially better than the HORRIBLE OEM Rochester carburetor it came with.

I have toyed with the idea of finding one of the modern programmable throttle body injection systems, and I am just too lazy to mess with fixing a problem that does not exist. Likely with a more modern system I can get more power, and better fuel economy, and it will pay for itself in 150,000 miles, maybe. But it ain't broke, so why fix it?

I could drop in a ton of power for not much money but that will happen right after I but the 30 inch wheels and monster thumping stereo. I will stick with my 15 inch wheels, and the two little 3.5 inch speakers in the dash.

[RKDinOKC]

On my GTS the oil pan is already baffled from Porsche. The problem it will have is the oil drain back from the heads. If you run at higher rpm too long the heads will fill with oil and end up starving the oil pump. They have an oil pan gasket that adds 1/2 inch to the oil pan depth that fixes the problem.

There are also some complicated systems with a separator setup to keep the crankcase vent from pushing oil into the intake. I just put a better baffle where the stock baffle is located. My intake is oil free. Originally thought that may have been my oil usage problem. That was until I found the there were some 928s Porsche did not drill the oil scaper ring groove hole that gives the oil someplace to go the oil scraper right takes off the cylinder walls.

[flipper35]

Oil will lower the octane of the fuel so it is good to keep out of the system. My valve covers have baffles for that. The heads and valleys are set up for good drainage so that isn't an issue. Has a windage tray also. The oil pan is the last weak link for this block. Should be good for the next one too, but I think an oil cooler would be a good addition. Adding another 100hp and 85# of torque might need a little more cooling. It gets warm now but not at the upper limit. The Cobra already has the opening for a cooler but I would want a thermostatically controlled oil cooler for those cool days here.

Rained yesterday, snowing today.

[Jim Richards]

Sunny & windy here today.

[GH85Carrera]

When I see how well the dry sump oil system works on the 911 I wonder why it is not used on more high performance cars. The big ol tank of oil in the fender just keep supplying the oil pump no matter how long you run high rpm or slide around corners.

Back when Helmuth Bott came to Oklahoma to talk to the War Bonnet tech group he took questions and answers. One person asked the max sustained RPM for long time running on a 911. He did not blink, what ever red line is for that particular flat 6 of the day. He said they would take a production cars off the line, and take it to a chassis dyno for a torture test. They would run it flat out for 24 hours, let it idle, check the oil levels, and continue for a week. Then run it on the bump track to look for suspension issues.

Of course we were all talking of the air cooled cars with the engine in the back like it is supposed to be!

[GH85Carrera]

My personal credit card was going to expire pretty soon. So the new one arrived last week. It does not expire until the year 2024. Dang that just sounds like the far distant future. 2024 will be here in a few months I suspect.

Once again I remember as a kid in grade school reading about Halley's Comet and I did the math and figured I would be in my early 30s and really OLD by then. I was one of the first few to see it in Oklahoma in 1986. I was big into astronomy back then and the astronomy club had a star party at a members house, well really his back yard. We had to stay up all fricking night to wait for it to rise above the horizon. It was just a little fuzzy blob in his 28 inch telescope. Totally disappointing.

I also remember we all went to breakfast, and then drove home. I was just going to bed about 8:00 AM and my mom called. I told her I was out all night looking at the stars, planets, and Halley's Comet. She paused and said they did not call it that when they were out all night. I told her, no really I was out in a field looking up. The cheapest hobby ever. Look UP!

[Jim Richards]

2024? Wow...I'll bet we'll all be getting around in flying cars by then.

[GH85Carrera]

Yea, I am still waiting for my jet pack.

[flipper35]

Originally Posted by GH85Carrera

When I see how well the dry sump oil system works on the 911 I wonder why it is not used on more high performance cars. The big ol tank of oil in the fender just keep supplying the oil pump no matter how long you run high rpm or slide around corners.

Back when Helmuth Bott came to Oklahoma to talk to the War Bonnet tech group he took questions and answers. One person asked the max sustained RPM for long time running on a 911. He did not blink, what ever red line is for that particular flat 6 of the day. He said they would take a production cars off the line, and take it to a chassis dyno for a torture test. They would run it flat out for 24 hours, let it idle, check the oil levels, and continue for a week. Then run it on the bump track to look for suspension issues.

Of course we were all talking of the air cooled cars with the engine in the back like it is supposed to be!

I think price is the issue. I would love a dry sump but they are $$$.

Jim, sunny and windy sounds lie sailing weather.

[Jim Richards]

Originally Posted by GH85Carrera

Yea, I am still waiting for my jet pack.

Too sporty for me. This is more my style...

[RKDinOKC]

They went thru several iterations to try to solve the 928 oil issues between both the oil getting thru the crankcase vent, high rpm starvation, and GTSs just plain burning oil.

People tried dry sump systems with mixed results.

There was one solution that used the smog pump to put a slight vacuum on the crankcase both sucking oil from the heads and keeping the crankcase from venting thru the intake. It however still had a catch can for oil.

There was another system that drilled holes in the heads to drain them back into the oil pan specifically to address the heads filling with oil.

There were several different baffle designs on the factory baffle for the crankcase vent. Most were a big improvement. The factory baffle was just a plate with louvers to keep oil from splashing directly into the vent.

Then they discovered most GTSs Porsche did not drill the relief holes to the inside of the pistons on the oil scraper ring groove. The GTSs were notorious oil users. There was no place for oil from the cylinder walls to go so extra oil that was scraped got burnt. Especially the more wear there was on the rings, the more oil got burnt. If you thought your under warranty GTS was using too much oil, Porsche replaced the motor with one that had the piston oil scraper ring communication holes drilled.

That is why I had the oil passages drilled on the pistons of my GTS. That combined with new rings (there was no cylinder or piston wear), cured the oil usage on my GTS.

They also discovered that if you added 1/2 inch to the depth of the oil pan it would increase the oil capacity enough it would let the heads fill, then pressurize and push the oil on thru getting enough oil back to the pan that the oil pickup did not get air and cavitate the pump.

The GTSs already have a baffled oil pan that keeps horizontal G forces from letting the oil pickup cavitate.

So my GTS has improved vent baffle, drilled pistons, and the deeper oil pan.

[RKDinOKC]

On the GTS went very conservative on the power upgrades and only then when another repair actually made is economical. The reason for that is the 951 before the GTS.

It was a 90 944 Turbo. It had be rebuild by a guy that was a Boeing engineer. It had a bunch of stuff. K27-8 turbo with custom chips, lightweight flywheel, Lightened knife edge crank, carilllo rods, had been nikasiled, the heads o-ringed, a boost/wideband/egt data logger, adjustable fuel pressure regulator, and a manual boost controller. It ran like a scalded ape. It had one problem though. The EGT got way hot accelerating. As I fixed and tuned stuff my goal was to add some power but also keep it as reliable as possible. Ended up with the shop I used putting a bigger turbo than I asked, leaving slop in the piston/cylinder tolerance (they thought it would rev faster being a little loose) and not torquing the bolts properly (bolts strarted coming out or breaking off). It had 420rwhp but at only 2500 miles was a disaster. To bad it cratered. Was planning make my own boost controller like the eboost controller that would let me program the boost curve through the rpm range for each gear. That would let me limit the boost/wheel spin in lower gears, but also crank the boost up where it could be used in higher gears.

So in maintaining the 928 I only added upgrades I was positve would not cause any reliability issues. The supercharge or turbos fur sure. Example: GT cams. When in needed new cams I went in with factpry GT cams. They made more power than the stock GTS cams, but could still use the valvetrain from a stock 928 engine. There were other hotter cams available, but needed custom springs, valves, and lifters to be reliable.

So my engine upgrades were GT cams, headers, x-pipe, and programmable ecu chips. Am adding 24lb injectors because tuned for the cams/exhaust it is using 100% of the stock injector timing at full load full throttle. Not a lot, but takes the 350hp crank (dynoed 295rwhp) to 380rwhp. Pretty significant considering the increase is across the entire torque curve not just bumping up the peak.

[Jim Richards]

iHola, y’all! It’s another beautiful Saturday out there!

[RKDinOKC]

Great!!! one of Jim's Saturday's we can all enjoy. Thanks for sharing.

[Jim Richards]

Christmas stuff all packaged ready for me to put them back in the attic. So, tomorrow will officially wrap that holiday up, just in time for a New Year. Lets hope it’s a happy one!