89 911 LS1 Conversion

[Yan2947]

e p slick, that is a sweet V8. Nice work! How expensive were the gear changes? 200mph! wow!

[e p slick]

I built this car 10 years ago so memory is hazy. Paul Guard pieces + labor etc. was around 5K.

EPS

[toyjet2000]

Yan, this is the system I have been running for a while.

It also houses the AC condenser.

[Yan2947]

What are your normal and high operating temps of the engine on a 90 degree day. On normal days (70 degrees and humid) I stay at 200 degrees but on 85 plus days I have seen my temps go to 220 and start to creep up to 225. I also know (or think) that 225 is really not too bad for these engines that like to run hot but any hotter and one has to worry. I know my radiator from Ron Davis is large enough for about 416 hp even though I am only about 350 hp (untested). I have had the car up to some high speeds on the hot days and I stayed above or at 220 degrees. Could not drop down to 200 until I met the speed limit. I have decided to add a small radiator in a new fiberglass front spoiler (935 model) from better bodies motorsports. Once I mount the spoiler I going to mount a radiator there. I have thought of adding a subaru wrx hood scoop to the wing. The 4" tall scoop would direct much more air into the rear radiator. Perhaps I should do that before I add the front spoiler. What do u think? It certainly won't look too stock.

[toyjet2000]

It works well.

I have been beta testing one on my new designs on my car for about 3 months.

Results so far.

In 100 degree Texas humid weather it maintains about 160 degrees in stop and go traffic. It goes to 190-195 when maintaining 80 mph. on the hwy.
The temperature is controlled by an adjustable rheostat that gets it signal from a
thermostat bulb, which in turn pulls in, a relay to cycle the cooling fan on and off.


With the same summer temperature settings:

On cold days the engine temperature runs a little hotter because it takes longer to turn the fan on because the temperature bulb utilizes the radiant heat off of the radiator surface area to send a signal to a relay to turn the cooling fan on.

You will have to re-adjust the rheostat in the wintertime to set your temperature to the desired value you want to maintain. My rear cooling system has never over heated or went near or above 210 degrees under any circumstance.

And keep in mind I am running a supercharger and a motor with over 600 hp.

[Yan2947]

I have a themostat. What is the rheostat and how can that benefit me with this rear wing? My fans seem to go on quite a bit.

[toyjet2000]

I do not know if it will benefit you.

My rheostat acts like your thermostat except it manipulates my fan control not water flow.

It is an adjustable device that senses temperature then pulls in a relay when that desired temperature is reached. The relay is hooked to my fan. All in a nutshell it is acts as an electronic thermostat rather than mechanical.

[shanghai_todd]

Yan
What RPM are you at and what are you considering as high speeds? I have done both a rear radiator in my initial conversion and this year swapped to a RH front mount and in both systems have seen similar temps that you have mention but in Florida weather. My experience is that holding the RPM @ 3K for a cruising speed can drive my temperatures upward in the 215~220F range and if maintaining @ 2K RPM on the highway is 205~210F.

Other factors to consider
- AIR in the lines (Took me 1 day of burping my system to get all the air out)
- Spark plug gaps (This can cause a hotter spark)
- Air/Fuel ratio
- Exhaust element (muffles tucked close to motor, back pressure, heat shielding)
- Dyno tune

Originally Posted by Yan2947

What are your normal and high operating temps of the engine on a 90 degree day. On normal days (70 degrees and humid) I stay at 200 degrees but on 85 plus days I have seen my temps go to 220 and start to creep up to 225. I also know (or think) that 225 is really not too bad for these engines that like to run hot but any hotter and one has to worry. I know my radiator from Ron Davis is large enough for about 416 hp even though I am only about 350 hp (untested). I have had the car up to some high speeds on the hot days and I stayed above or at 220 degrees. Could not drop down to 200 until I met the speed limit. I have decided to add a small radiator in a new fiberglass front spoiler (935 model) from better bodies motorsports. Once I mount the spoiler I going to mount a radiator there. I have thought of adding a subaru wrx hood scoop to the wing. The 4" tall scoop would direct much more air into the rear radiator. Perhaps I should do that before I add the front spoiler. What do u think? It certainly won't look too stock.

[Yan2947]

Todd,

If I were to maintain 3K RPM on 90 degree weather I would never go above 205 degrees. Anywhere above 4K is where it creeps up. At this point in the year even at 5K RPM I am not going to heat up above 200 or 205. I think my radiator is oversized well shielded and a good portion of the air being sucked through goes out the back of the lid before entering the engine. Plenty still get into the engine area but it does help to have the cut out at the back to allow plenty to fall out the back. I will have to take some fall cruises to see where I am now with temp/rpm and speed. The car has been quite a sunday driver so I need to see where the open road sends the temp gauge. I will try it again this week and post some better results. If anyone has an extra - not used - wrx scoop (4" tall) please chime in!

[toyjet2000]

“Toyjet Cooling”

Lets keep in mind when others post about the pros and cons of the rear radiator system and their experiences, they are not referring to the Patented "Toyjet Cooling System".

They are referring to a system that they made themselves or purchased from some other entity other than Toyjet Conversions Inc.

My Toyjet cooling system operational cooling temps are much different and much more forgiving than what I am reading in this post.

I am challenged to get my LS1 to run the desired temperature the LS1 runs optimally at. I have absolutely no issues with my car overheating or ever getting near or past 220 degrees in any circumstance or weather condition.

When I first invented the Toyjet cooling system, I experienced exactly what you guys are going through. After extensive research and development I solved the over heating issue. I participate in as many local parades and car cruises as I can and occasionally drag race my vehicle with no cooling issues at all. The design of the system is the key.

[Yan2947]

Clemon,

I realize you have a lot of time and money invested in your design and appreciate all your help. I have no problem dragging my car in 1/4 runs and keeping the temp low and there is no way my car will ever overheat in a parade on 120 days in NY or Texas. The only issue I have seen is at long distance high speeds. A highway or track at 120 mph for 10 miles. The temp jumps up. With your DP 935 new tail that is not so different then my turbo tail with the cut out. I think it is very different then your patented tail. That tail is much higher then mine and allows much more heat to exit the rear. If your dp tail is doing the exact same thing as your patented tail then we have to be pretty close on temps unless....... you are also making all of your hot air from your radiator on the dp tail exit the rear without ever hitting the engine. That would be harder with the 930 tail. If you can see something that I am missing please feel free to call. I will PM my number to you.

Yan

[Yan2947]

Todd,

after your final conversion are you saying that your temp on the motor were about the same with your front compared to your rear radiator with the same weather conditions in FL?

[toyjet2000]

Yan,

You are correct.

I am venting to the outside. My air is exiting about 50% outside and 50% in the engine compartment. Since my wing is slightly longer than a stock Turbo tail, no air is hitting the engine. The 50% that's in the engine compartment is blowing in front of the motor, right over the deck-lid latch area and water pump adapter area. My wing is a custom made wing that is about the width of the stock AC condenser longer than a factory turbo tail. I purposely designed it that way so I do not have hot air blowing directly on top of the engine. This could be making a slight difference, that's my guess.

[Yan2947]

Check out Toy-Jets water pump adapter and motor mounts. I like the fact that he doesn't use an engine cradle. More room down there without the cradle. The water pump adapter gives a bit more room and is neater then using that extra hose. Single line in/out on his water pump. Nice and neat. RH is great but Toy-Jet is very inovative. I now understand why his rear wing/radiator works. I shall be upgrading my wing in the future to his new wing design....

[toyjet2000]

Here are the engine mounts

[Yan2947]

Clemons,

so you have no issue with the engine cradle since you don't use one. You have more room on the bottom. It took quite a bit of work to get the exhaust around the cradle. Nothing to crazy but you avoided that all together. It is great to have 2 schools of thought on this idea. People can make their own choices but this gives a great alternative at a respectible price! Nice to see the actual work!

thanks!

yan

[sirhiss]

Hello Yan
Now i have recived my "batwing" (Corvette) oilsump and my new hollow torsion bars 29mm is on the way from sway a way. What does mr. toy jet use for rear suspension?

[Yan2947]

Sirhiss, I am not sure that Clemons changed his torsion bars but he likes 1" taller tires. That may solve some issues with oil pan slamming/squatting!

[mystro]

X2......just cause you can, doesn't mean you should.

Originally Posted by cole930

Don't mean to be negative but, I love these cars too much. To me it's like cutting the center out of a Picasso to insert an Al Capp cartoon.

I certainly respect your right to do what you want with your car but your either a Porsche guy or your not. Your not. I would respectfully encourage you to go buy a Corvette.

Cole

[pcar9119]

This is a good discussion on this mod. Don't ruin it by coming on this thread and *****ing. I'm trying to learn somethings on this topic. Don't start wailing about correctness and purity. There's a thread for that too...