tonypaul

iTrader: (2)

Yes I have heat, but rarely use it here in Texas. The hear core is in my dash with heater hoses from the engine. I have a Vintage Air a/c-heat setup I just need to have some hoses made to complete the a/c part.

No kit was needed to install the LS4, I just fabbed up some motor mounts to mount it. The drivetrain came out of a 2008 Monte Carlo SS (fwd) it has the 4T65ehd auto trans which is controller by a Magnashift stand alone system. I made a homemade wireless paddle shifter out of a $20.00 ebay remote door unlock kit and some used Audi paddles.

This pic shows how my air flow is, its completely seperate from the engine compartment. The fans are on the back of the rads pulling air out. I did have some air flow problems in the engine compartment but I have since made some more openings to get the air out....


Im sure your problem is in the tune, which is sad that you spent so much effort changing out the stuff you did. But I think your on the right track, a good dyno tune should fix it.

yan2947

My next step is tuning. I really appreciate the advise and quick responses. My fingers are crossed and I will let you all know what those results are. They do make sense and it is any area I have never thought of.

My car, at 70 mph, is at 3000 rpm's so it does not take too much effort to get to 4000 rpm's. Is 4000 or 4500 rmp's too much for highway driving for these motors? Or do I need to swap out a 5th gear? I really wont drive often at 4500 but on long trips it does get loud.

yan2947

Tonypaul, that is a great setup. Most of the 911 setups (pre 1990) cut out the front tub to put a radiator there. I think there systems work very well but I hear complaint of the heat generated that goes into the cabin. I don't have to worry about that. Same with your system. Those tunnels are amazing. Keeps the heat out of the engine bay. You mentioned that you had to do some venting also? I was going to use one of my extra 14" spal fans or get a smaller one and pull some of the heat out of the engine compartment through the passenger side fender. There is a large opening in Porsche cars where an oil tank used to sit. I don't have the tank so I can vent out there. One other thought I have is that my air filter for my intake, as shown in the pictures, is in the engine compartment and hot air is all around. I plan to move that somewhere in the future. Do you think that has some significant appeal? I will visit the tuner tomorrow and hopefully he can change the timing tomorrow or soon...

thanks!

tonypaul

iTrader: (2)

I just cut 2 openings in my engine hood deck to help get the air out. I have almost everything for a cam swap and a turbo so I know the turbo is going to add even more heat. I have a LS6 engine cover (other pic) and it was covering up the only other vent on the engine hood so no air was getting out.
I switched the LS6 cover for a Lamborghini engine cover (center piece) that helped with the air flow but it still could be better.




I have just repainted the whole car 2 weeks ago and today got the car body completely wet sanded and buffed and started working on all the other panels (doors,bumper, front/engine/rear hoods,ect). I should be done with all the wet sanding and buffing this friday. Im going to put some Plasti-Dip (black) along the bottom of the car and the rear wing as well then start to put the car back together. Hopefully I will have everything I need to do the cam/turbo swap by Oct.... It never ends~~~~

yan2947

It does look incredible. It is amazing how those cars turn out if done right. You certainly are putting some time in it. Be careful with the Plastidip. I did my wheels and have to eventually remove it. It is peeling a bit. Vinyl wrap might be a better option with such a nice car!

bustac

iTrader: (1)

I tried 3 different Radiator setups each couldn't cut it, one was a Rod Simpson. My wife bought me a Renegade setup for Christmas and never had a problems since, nice huge fan 19". Fans generally work best as a pullers. Mine was just a SBC but same challenges.

yan2947

bustac, which fan was it? 19"? Didn't know they came that big. Do you have the model number off the fan?

thanks,

Yan

Sarg

iTrader: (6)

A couple things come to mind.

The first being the water pump. According to the articles and advice I have seen from griffin, there is no such thing as too much water flow. Griffin says that is a old myth. If you have access to a 55 gph, I would use that as you have a kinda smallish radiator.

The second is the tune. If this is a NA motor (no forced induction) revving at 4000 rpms for an extended amount of time, the tune will really need to be spot on. Just slapping in a ecu from a camaro....well it could be all over the place. If it is a MAF based car especially, unless you have all original factory air box pieces (from the camaro) routed in their original manner it is going to be off. I just tuned a buddy's 1981 Camaro that he transplanted a 2000 LS1 in and it was stock, but his MAF tubing was not. He was off as much as 25% in some areas!!! That can make a HUGE difference.

At 4000 rpms even if under a low load, 43 degrees of timing seems a bit high and I would want air fuels in the 13.5 range. These motors really were not tuned to cruise at those rpms. The 6 speed cars would cruise at around 2500 rpms, lol. If your tune is off and the timing is high there is no telling what may be happening in there.

Lastly have you considered just adding a small additional radiator somewhere in series or maybe an oil cooler to help pull some more heat out? Just thoughts that came to mind. I love the build though. Very original!

yan2947

Sarg, thanks for the input. I am hoping the tune really helps. The local tuner is taking his dyno apart this weekend so I won't be able to go there until the middle of next week. My fingers are crossed because I have really tried to take out all the kinks that could be a cause of the heat rise at 4000 rpms. I realize the Porsche trannys ran quite a bit higher in rpms then the gm cars. One day I will put in a really tall 5th gear. If the tuner helps then I am set but if not I will be adding an additional radiator somewhere in series. Regardless, the taller gear will really quiet this monster down on long road trips. I am at 3000 rpm at 70 mph in 5th gear. Once the motor is dropped it is not too difficult of a gear swap. The motor drop is a 6+ hour to 12+ adventure with my mechanic.

thanks for the comments and advise!

Yan

Andy1

Yan,

That's a nice looking car! I always liked that black on black look on the 911.

You've gotten some solid advice to help resolve your problem. Certainly, the timing must be correct, otherwise you're fighting a losing battle. I'm not a big fan of horizontally mounted readiators since it's incredibly hard to pugre all the air out of such a configuration, and any incidental air or air bubbles could trap there over time. However, if I were to assume you did get all the air out, that radiator ought to be plenty large enough to cool your LSx motor. If after you resolve the timing/tune issue, I would venture to guess you don't have adequate air flow through the radiator. Remember, that getting the air to exit flow is more important than how it intakes. You must have a adequate pressure differential between intake and exhaust, otherwise flow is compromised.

Though not the same car, I have a 914 Porsche with an LS1. The temp stays dead on 195 degrees in hot SoCal weather. I'm using an AFCO dual pass ASA racing radiator mounted in the front of the car. Intake is at the front, and exit air is through the hood; it is all ducted and sealed. I'm using the stock LS1 water pump.

BTW, did you plumb in the steam vents on the heads?

Andy1

yan2947

Andy1, steam tub goes back to a hose coming from the radiator. I think that is what you mean? I am hoping that the radiator is big enough. There are so many examples out there where rear radiator can work. My horizonal one has no air in it. I have learned, as you can guess, how to bleed it. The cap is on the top and I bleed it by raising the hood where the cap is at the highest point. It is a sealed system and no air gets back in once it is closed unless of course I burst a line...

thanks!

ktm240z

iTrader: (1)

I did not see this addressed anywhere. Are you sure your radiator hoses are not kinking? I see in the picture that the passenger side hose is kinked when you open the rear deck. I assume that it straightens out when you close it, but are you sure the lines are not kinked when closed?

yan2947

ktm240z, very perceptive. I did have a problem before. The passenger side is perfect. The driver's side had an issue but it has been addressed. I wish there was a pivoting radiator hose connector but there is not.

cam

iTrader: (9)

Kinked hose very likely. LS engines are not known for being difficult to cool. Time for some hard walled piped in coolant lines perhaps with flex connectors. Seems odd that it happens so quickly, almost as if coolant flow stops altogether... which sounds like kinked hose could be very suspect. Good luck

yan2947

Its not kinked hoses. I do use a flex hose with some nice aluminum bends. It had been kinking before but not at all now. I took the car down the road again today while monitoring the timing advance. It does jump right up to 43 degrees anywhere above 3500 rpms or so. Don't know if the tune will solve it but it is the next step...

yan2947

Finished up at the Dyno today. Stock LS1 after being tuned had the following:

362 HP at the Crank/Engine and 315 at the wheels
386 Max Torque at the Crank/Engine and 336 at the wheels

There was a lot of tuning done. Lowered the advanced timing and corrected all the ratios. The car ran incredibly cool. It was a cool day today, in the 60's so the real test on the coolant system will be in the summer but I tried to get the car to climb in temps. I drove for 5 miles at about 4200 rpm's and could not reach 200 degrees. The fan now comes on at 180 and shuts off at 168. Previously it reached 195 before kicking on. I have all the confidence that I will not get above 220 on the hottest days of the summer.

I plan on taking the car to the drag strip on Sunday to see the times on the car.

cobalt964

nice build yan, I am building a 1993 911 ls3

cobalt964

glad to see you got a tune. likely that was your issue or most of it.
ill address some of your questions you have posted.

a good rule of thumb in these cars is at least a griffin 16x26 aluminum dual or triple core radiator with dual 12" spal fans.
pcm set at 180/165 ish for fans
meziere 55gpm inline electric water pump
drill a 1/8" hole in your tstat as a bypass(renegades recommends this)

gearing wise, if you wish to drop rpms at highway speed or others use a g50/05 ring and pinion. you will gain 4-12mph over the spectrum of the gears and drop rpms at 70mph. if you want further gearing get a g50/03 2nd thru 5th along with the g50/05 r/p. or the ultimate of coarse is a g5050 or g5052.

and last but not least, a ls3 non dry sump gmpp oilpan with trap door baffles. have a nice skid plate for under it to. other than that, have fun. my .02

yan2947

Thanks for the advice. One of the most important reasons for doing these builds online is for getting help and giving help and this site has some amazing people. Thanks! My build is documented mostly at:

http://forums.pelicanparts.com/porsc...ersion-17.html

Had I known about this site first I would have kept it here. Makes more sense!
thanks again!