89 911 LS1 Conversion

[Bill Jennings]

Yan,
I love my car just the way it is which is almost 100% pure Genuine original Porsche, its fairly rare so I am not about to hot rod it. Thats just me with my particular car
However, I pretty much love everything Porsche, including hot rods, modified, conversions etc and I love what you have done.
This site has tons of examples of owners brave enough to make their vision a reality and like you some do it very very well.
As for those that have been harsh with you they are entitled to their opinion but have to say I was impressed how you handled them and kept on going on your way.
By the way I probably wouldn't swap my car for yours but I sure could make room for it in the garage next to mine anytime!
Cheers Mate!
Bill

[Yan2947]

Bill, thanks for the kind words. We all enjoy different things in life or life would be pretty darn boring. Many people modify their cars on Pelican and get help from the entire forum. I have certainly benefited from the forum even if a few have been harsh. The amount of energy and wisdom here is incredible. Dedication of the members speaks for itself.

[Mitch Leland]

I installed a taller ring and pinion in my 996 C2S-LS3/480 HP (removed the front wheel diff), at 70 MPH I'm turning 2,200 RPM. The net weight of my car after removing the front diff and installing the LS3 motor is 3,030 lbs. That's net with the fuel removed at 6.5 lbs/gal.

With the taller gear the performance is still there in all gears, (387 ft.lbs. torque) also the engine is a lot quieter at cruise. In fact I get more tire noise than engine noise... Breath taking to drive...

[Yan2947]

Mitch, sounds incredible! Do you know where your rpm was prior to the change? Did you put in taller gears and taller ring and pinion? Love to see you keep a chart and post it as you visit certain speeds...

And is you hp and torque at the wheel or crank?

Thanks!

So much snow here. Can't wait for spring!

[Mitch Leland]

Yan,

Here's the speed/RPM chart for the taller ring and pinion. The engine is rated at 480 HP, the car dyno at 391 HP at the rear wheels, and 381 ft.lbs. of torque. Max torque peaked at 4,600 RPM.

[Yan2947]

Mitch, those are some amazing numbers. Did you ship out your tranny? Very costly I would assume. If I drop my motor again I am sure I will have to follow suit. Can we see some new wide shots of your beast on your build...

[Mitch Leland]

I delivered the transaxle to Renegades shop in Las Vegas. It gave me a another opportunity to ask questions and look around. It was expensive and added a lot of cost to the build, however I believe that it's the correct decision for the long haul.

I can leave in 2nd gear now, with the stock Ring and Pinion I don't think you would need lst gear. Guard makes gear sets for the 911, but not for the 996. I've got hundreds of shots of the build, but most are detailed shots.

[Yan2947]

Took the 89 911 LS1 to Lebanon Valley. The car ran a 12.554 at 112.83 - bone stock 04 LS1.

https://www.youtube.com/watch?v=VOSv-dxFxtQ

[drmatera]

Very cool Yan2947. Car sounds great too

not for nothing but with more practice (read aggressive) driving she should go into the 11's

[Yan2947]

I am sure practice makes perfect! I will try next time. Does anyone have a completely stock LS1 with 1/4 mile times less then 12?

[ChrisP911]

great job....... Still waiting on mine to get done...hate body shops.

[Yan2947]

I am using the Toy Jet system. I really wish a couple of LS guys could let me know what their temps are when at high rpms. Even the guys with tall gears when they drive down the road in a lower gear at 4000 - what are their temps on the LS temp sensor (factory installed)... for front and rear radiators. I have a good sized radiator and by math it should do the cooling. I am not sure that the LS motors were meant for high rpms and therefore the real answer is tall gears or a larger radiator...

Last Wednesday it was 86 degrees outside
3000 RPM for 10 miles Temp of engine coolant reached 208 degrees - MAS temp was 84 degrees
3500 RPM for 10 miles Temp of engine coolant reached 233 degrees - MAS temp was 82 degrees
4000 RPM for 10 miles Temp of engine coolant reached 244 Plus degrees - MAS Temp was 82 degrees - the temps at 4000 would have risen but I wouldn't chance it.

3000 rpm on highway 5th gear around 71 mph
3500 rpm on highway 5th gear around 82 mph
4000 rpm on highway 4th gear around 74 mph

Can anyone else post some results here. Thanks!

[dtakenname]

Hello,

Have you experimented with different types of thermostats? Maybe the coolant does not "stay" in the radiator long enough to cool off before being sent to the block.

3000 Rpm for those speeds seems too high for such a torque generating engine too.

By the way when you drag raced the car, did you took off in first or the second gear?

Best wishes.

[Yan2947]

I have removed the thermostat but didn't notice a difference in temps. It is back in the car. Getting a new temp sensor today to see if it could be that. At Lebanon Valley I used second gear for the runs except the last run where I started in 1st. My last run was the best but each run saw an improvement. I think the extra shifting will prove to be slowing the car down. My second gear takes my to about 60 mph while 1st only to about 30 mph.

[drmatera]

Originally Posted by Yan2947

I am using the Toy Jet system. I really wish a couple of LS guys could let me know what their temps are when at high rpms. Even the guys with tall gears when they drive down the road in a lower gear at 4000 - what are their temps on the LS temp sensor (factory installed)... for front and rear radiators. I have a good sized radiator and by math it should do the cooling. I am not sure that the LS motors were meant for high rpms and therefore the real answer is tall gears or a larger radiator...

Last Wednesday it was 86 degrees outside
3000 RPM for 10 miles Temp of engine coolant reached 208 degrees - MAS temp was 84 degrees
3500 RPM for 10 miles Temp of engine coolant reached 233 degrees - MAS temp was 82 degrees
4000 RPM for 10 miles Temp of engine coolant reached 244 Plus degrees - MAS Temp was 82 degrees - the temps at 4000 would have risen but I wouldn't chance it.

3000 rpm on highway 5th gear around 71 mph
3500 rpm on highway 5th gear around 82 mph
400 rpm on highway 4th gear around 74 mph

Can anyone else post some results here. Thanks!

Yan, could be an air flow problem. At speed you could be creating some dead air space in front or around the radiators. My buddies mustang used to do that. Around town the temps never got over 180* but as soon as he hit the highway they went up. The faster he went the hotter it got.

Yes the engine will produce more heat at higher rpm so that is normal, making sure the coolant slows down enough in the radiator to dissipate heat is very important but so is lots of air flow across the radiators. Can we see some pics of your radiator locations?

[drmatera]

ok, i just ran back thru the post looking at the radiator. Looks good to me, I say ring and pinion time. These Ls motors like to idle down the highway. My 85 500 SEC has an LS1 / T56 swap and I can go 80mph at well under 3000rpm

[Yan2947]

Very sweet MB! Speed isn't the issue. I can replicate the issue at 20 mph in first gear at 4000 rpm. Sensor was just replaced and I will see if issue is still there...

[drmatera]

Originally Posted by Yan2947

Very sweet MB! Speed isn't the issue. I can replicate the issue at 20 mph in first gear at 4000 rpm. Sensor was just replaced and I will see if issue is still there...

oh ok, very interesting. That changes things. Possibly not enough ignition timing in the light load high rpm bins? That set-up uses a remote water pump right?

[Yan2947]

Can u take your MB out for a short ride at 4000 rpms for 5 miles low speed and let me know what temp u reach on an obd2 device for the internal ls computer?

Yan

[drmatera]

Originally Posted by Yan2947

Can u take your MB out for a short ride at 4000 rpms for 5 miles low speed and let me know what temp u reach on an obd2 device for the internal ls computer?

Yan

I can try it on the way home this evening