doorgunner

Today I discovered more benefits that the radiator exhaust air diverter provides.......

Normally during the summer when I raise the hood after the car has warmed up thoroughly or has been driven, a super-heated blast of air hits my upper body...after I reach into the engine bay to do/check anything my shirt becomes wet with perspiration....by the time I am finished making a carb adjustment/relocating a wire that is too close to the exhaust manifold/adjusting the distributor/etc.....both hands are toasted from "swapping them out" as I do the work. Also...components that I handle are so hot that it takes longer to accomplish anything.
That is now all history...the dread of raising the hood is now gone LOL (I may be eating those words after an hour test drive...but for now....... )

doorgunner

Three piece diverter (two side-pieces and main panel)....It is a very simple modification....fabrication and installation was 4 hours---fitting the diverter by making minor clearance cuts took most of the time......





The diverter installed and viewed from above the engine bay.....





View of lower end of diverter where radiator exhaust air exits to rear of underbody....







View from under car upward and inside diverter toward electric puller fan

F22

I'd be curious as well, Sir Doorgunner, as to how it works, when you hit the hour mark, because that's been the typical period of.time, as to when the interior heat, really gets bad. Great looking and inventive mods, though!

F22

Spark Plugs? I've got to do some actual temp measurements next week, but I'm encouraged by the effect a simple spark plug change had on the interior heat. When we pulled the plugs, we found out that we had installed 'cold' plugs. The threaded end of the cold plug, was half the length of the 'hot' plug and measuring the depth of the aluminum head, the cold plug only made it half way down the hole! Meaning, the spark plug and the electrode didn't even extend.out into the combustion chamber!

With no timing change, whatsoever and temps in the low 90's, went out for at least an hour, leaving town and getting out into the hills, where I engaged in some spirited driving. Went out to a local biker hangout in the woods, turned around and went back. While I felt that there was some heat, it wasn't nearly as bad as before! I drove barefoot too (it's not good to drive a four speed with flip-flops) and usually, the soles of my feet would feel like baked potato skins, but didn't get that at all. It was pretty warm, but nothing like the blast furnace between my legs either.

I'm thinking the cold plugs acted very much like a retarded timing situation, because the electrode was actually buried in the spark plug hole a good half inch! That delayed or late firing, was still happening when the exhaust valve opened, transferring a lot of excess heat out to the exhaust.

Right now, it's just a theory, haven't researched it yet, haven't measured yet, but just reporting on the results.

doorgunner

F22....thanks for the encouragement and advice (PTSD/ADD/ETC make getting anything accomplished a major obstacle). I realize the initial modification is somewhere between Redneck and Bubba, but I needed to try something because of all the "heat" threads....and like I said "Do not do this to a real car!"....LOL! I will try to cover/install the seats and get the infamous La. State Veh. Inspection sticker Monday which will also solve the 1 hour curvey-road-cabin-temp. question.......(whew!)

I am going to pull one of the new plugs now to check the depth-of-fit....(no sense in leaving that turn un-stoned). I'll bring the I.R. gun with me to get on-the-road readings Monday.

doorgunner

I've spent the last 5 months indoors/shades closed/ ......but I'm starting to snap out of it!

Remember----I'd never modify/Bubba the CAI or radiator exhaust air on an original/stock Corvette!!!

So.......here goes with the latest results........

The floorboard stayed around 3 to 4 degrees above the ambient air temp today at the gas pedal and along the tunnel.

There's other good news.......(Copied from Doorgunner's '68 Convertible Project )

I drove it hard and put it up DRY!

The cooling system worked like it's supposed to work/no more 220* overheating.....180*,

The recovery tank only needed to catch about a pint of coolant about a minute after I turned the engine off.

I'll try to get some video/audio of the Harley mufflers on the open road.....IF the Kodak is up to it.

Remember---I would NEVER take a stock Vette and put a Bubba CAI in it.......

So....since there was no air cleaner or radiator fan or shroud on the car, I decided to (re)invent the shroud/cleaner......EXCEPT....I went strictly electric fans which are independent of each other------

One fan has ductwork just for exhausting the hot radiator air UNDER the car, rather than onto the engine.








The other E-fan takes ambient air from the front grills and forces it DIRECTLY onto the engine......the blue arrow shows the driver's side 4" inlet duct........the result per the infrared gun----65* ambient air going into grills---68* air blowing on the engine/engine bay. when E-fan turns on at 180*......








The CAI takes ambient air from it's 4" ductwork....infrared gun shows 65* ambient air at grills----68* at the air cleaner lid with hood open.......




Basically......the underhood temperature went from 170* to approx. 10* above the current ambient air temp......no more raising the hood/toasting my fingers while trying to removed the air cleaner/with the engine running after driving for an hour!

More testing will be done this weekend/I'm trying to make a 2 hour test drive to get better readings with the infrared gun.


Edit: Another member nick-named the enginebay mods...................... R2D2 .........LOL!!!

doorgunner

Update: After dealing with engine overheating issues, the cabin heat problems are under control. Now...if I could make the modifications look less-Bubba.....and MORE-resto-mod!

(Rookie-me didn't realize how much warm air goes around the transmission in the tunnel....those infrared guns really reveal lots of info!

I know I've said this a dozen times....but I would never expect others/nor would I make these engine bay mods to an original car.

But it does prove that "things" don't have to stay the way they are because auto manufacturers won't go the extra mile....not that they haven't done a great job on the Corvette.

F22

You're doing a great job on the mods, DG. It looks fine to me and if it,works, why not. There are certainly areas on these cars, where the engineering is definitely questionable!

mklrly

I think I saw this somewhere on this forum, but it bears repeating.

Make sure you have the weatherstrip on the top of the radiator.

Otherwise the outside are comes in the front and bypasses the radiator, getting further heated by the engine and flows into the vents, very hot. Not to mention overheated engine.

I went to Lowes and got 2 inch foam weatherstrip, glued to the top rail of the radiator across the entire width of the engine bay.

There is and official part for this, but my solution was only about $10 including some 3m weatherstrip glue. Also make sure the hood gasket is in place.

Dropped the engine temp nearly 60 degrees, and made the interior much more comfortable.

I have a 1979 L-48 auto.

mac79vette

I have a 79 that had a interior heat problem but I have solved it. I cover the underside of the car with the dei floor and tunnel shield and lined the inside of the floor with dyno mat and the fire wall with Dyno liner. Before driving this car would back me and long trips would burn my leg. In fact my carpet gad melted to the floor next to the gas peddle. Now with the outside temp at 105 and driving at 80 mph for a hour + the floor is the same temp as my seat. This is a 355 with 335 hp at the wheels long tube headers a t10 and 3.55 gears. But also everything else in the car is sealed up well.

doorgunner

Thanks Men....I made sure I did every improvement this thread offered...the top-radiator-foam was missing on my project car (along with many more things LOL)....which made the interior FINALLY comfortable (there's nothing like sitting at a traffic light with the top down and SWEAT/not perspiration LOL.....pouring down your face.....NOT BECAUSE OF THE SUN.....but because of the 140*F inner firewall and floorboard.

Also....I believed in 100 years of 'AUTOMOBILING", there MUST be a better way of cooling the engine/engine bay.....and give extra life to the engine and accessories, while helping to keep unwanted heat out of the cabin.

Now, the radiator is happy with it's own fresh-air cooling fan.....the engine is happy with it's own fresh-air cooling fan....the carb is happy with it's "CAI" (if you can call 95* summer air Cold.....LOL).......and my poor feet are happy!

persuader

Gunner, I do have to say that your idea of a hot air diverter for the back of the radiator is a swell idea. That is something for people to consider in the way on lowering under hood temps. Thanks for the R&D.

doorgunner

persuader...... thanks......but I refer to it as Bubba Gone Wild.

I just came from the garage after doing a re-mod to the mod of the CAI....I reversed the two flexible ducts to draw air from the "water trough", as another Forum member has done in the last year (can't remember his name). I think I'll go to the garage and get a pic of the new conflageration.....errrrrrr....configura tion.....be back in 10.




Since CAI is a given.....I'll order one of those nice/neat kits to draw air from the cowl.....that will eliminate the R2D2 dusts to the air cleaner.

mac79vette

Your fuel line next to the exhaust manifold is making me nervous.

doorgunner

Thanks for keeping an eye on me/I need all the help I can get......it's a "camera illusion".....it's actually no closer than 5" at the lowest/closest point near the exhaust manifold....I couldn't see how the original route would do any good with steel line running next to-up the front of a 200*+ engine block. The rubber hose looks Bubba'd, but it stays cooler. Once I re-do the engine bay, all rubber will be new or braided/the upper radiator hose will be re-located to the lower location and a correct upper hose will be installed (I've been solving overheating problems the last month...aarrgg!)

mac79vette

I had a car when I was 16 that a rubber fuel line caught on fire and burned the car so its just a pet peeve of mine.
Here is how I did mine.



But back to the topic here are some photos of the insulation that I used.









It really works well. The car was supper hot before but this insulation fixed the problem. Before I had lots of felt padding in the car, the factory tunnel shield and the foam collar. I felt that I did not need the foam collar any more or the factory tunnel shield so there not in the car currently. Also before the shifter would get so hot that for highway trips that were over an hour I would bring a rag to keep from burning my hand on the shifter but now it is the same temp as everything else in the car.

doorgunner

Let's compromise.....I'll do a steel line somehow.....but I won't run it in front of the block/too much heat!
Annnnnnnnnnnnnnnd...that's a great-looking project!

LudemJo

Great job Doorgunner! I am impressed with your engineering and execution. It looks great just the way it is.

Just a thought, given the direction you are going with this. I wonder what advantages may be gained by adding aluminum plate under the complete engine bay clear back to the back of the trans? My thought process being that it would allow the hot air from the radiator to continue flowing under the car unimpeded. Now, I don't know what problems that may cause in the engine bay, but there will be some openings to let out ambient high temps around the running engine. I am thinking of the big motors they put in boats that are completely sealed away in an engine bay with no airflow...doesn't seem to be a problem for them.

You are doing great work here. This just peaked my interest and got me thinking about other research ideas.

John

doorgunner

It just so happens that I have a large piece of (experimental) medium thickness steel sheeting that I've been wondering about....annnnnnnnnd, those fender louvers/gills need to be more efficient

Haggisbash

Just thinking out loud, I wonder what would happen if the side gill vents were fitted with fans to help pull air out of the engine bay?