the engine in my mk2 runs at correct but i know there is a lot of heat in the engine bay i dont want to vent bonnet any suggestions please

 

I know heat and how to eliminate it in a Jaguar as I have a 400+ HP V8 in my Jaguar 3.8s. I encountered the exact same scenario as my high capacity aluminum radiator kept the V8 plenty cool but the engine bay temperatures rose high enough to cause the fuel to vaporize and many other issues. To me these Jaguars like many old cars were never designed to run in stop and go heavy traffic and if you upgrade the power of the stock or in my case a powerful V8 you just make it poor design even worse. Look at most every new car besides the intake for the radiator they have additional vents to vent the engine bay as well as brakes and in the 1960's they never designed that into the cars.


The solution is what Dave at Market Auto in San Jose, CA 408 292-1828 designed. That was a custom aluminum ram air intake which is very subtle and under a custom front valence below the bumper. The flexible valence really improved the car's esthetics as Jaguar left the stock front frame, etc. exposed which looks ugly and unfinished. The ram air intake only goes a little lower yet it funnels a large amount of air up and then directs it around the engine and enables the air to flow out. On the inner fender wells we have triangular vents which allow the air to flow out. This works so even when I encounter close to 100 degrees outside air I can even run the AC with no issues. This was the single best solution to eliminate this issue.


I also had my headers coated with the 2500 extreme Jet Hot coating which helps a little but by far the ram air intake is the key. You can contact Dave as he is making one for another Jaguar owner I know. It looks clean and works wonders... I drive my car daily in heavy traffic as well as race it hard whenever I can with no issues. I have put over 45,000 miles in roughly the first year after my car was finished.

 

thanks for the help that is the answer'' is that a oil cooler at the bottom vent

 

Then you have nothing to gain and nothing to worry about. The car is operating as per design.

 

The round cooler is for the power steering. There is one scoop for the power steering and one for the engine bay.


If you rarely drive your Jaguar and never get the car in long 1-2 hours of stop and go, and if you have a bone stock car, you just might not encounter heat issues that would stop the engine. What you can still get is excessive heat that will plaque more havoc on the famous Lucas electrical. What I also encountered besides too hot issues that caused running issues was that many electrical components, such as, air horn, electronic ignition, etc. failed way early prior to these modifications and now those are a non issue.


There is a lot to gain with these modifications to me as they are a great upgrade even if you do not have a V8 as the engine bay in these cars run very hot and if you do performance upgrades for more power which these cars really could use to keep up with modern cars then the issues increase. I pushed my car harder than most as how many of you have driven your Jaguar over 45,000 miles in the first year and in daily driving situations with 1-3 hours of stop and go, in heavy traffic, rain or shine, and from 40 degrees to 105 degrees with no reliability issues?

 

Primaz that's a really interesting solution. I've vented my Mk2, wrapped the exhaust, covered the hood and firewall with heat shield, and run a huge aluminum radiator and E-fan and still gets HOT and pushed 90*C in traffic.

I'm going to call him and see, I imagine it would be a pretty similar solution for a Mk2 as an S type.

Does it require a lot of cutting or drilling holes to install?

 

Don,


I did the same as you I spent a lot of money on all these other areas which did very little to solve the key issue. Yes it should be nearly the same on a MK2 and no cutting is needed just some small holes to then screw the pieces in. Next time you look at any new car, look at the multiple vents and you will see vents clearly for the radiator, and then other vents for the engine bay and in performance cars brake air vents. Now look at your Jaguar and all you see is the one small grill for the radiator...

 

Stuffing the Ford Windsor has presented its own set of problems, along with my penchant for horsepower.
This lead to a very large exit for under the hood heat. I've moved the footwells back 3" and recreated the rear section of the inner fender that was once the footwell. Now there are two 3" x 12" exits to the underside of the car, between the bottom of footwell and the new inner fender. This crowds the rear seat, not to mention, the other required modifications. So not likely an ideal situation in most minds.


The attached photo shows the gap between the rear of the inner fender and front of the footwell. This pocket will be sealed off from the interior and open at the bottom for enine compartment air flow and exit.

 

primaz,
I just noticed the black spoiler that goes side to side in front of the aluminum scoop.
What is that from? thanks

 

Dave at Market Auto took it from a modern car and modified it for my car since he owns a body shop but I do not know which car it is from. I just told him that I really did not like the front of the car not having any front valence and he designed and installed it for me. It really makes the front of the car look nicer as the stock 3.8s has nothing to hide the ugly frame, etc. It is made of a flexible material as the car is fairly low so it works great as none of the many rocks that hit it do not make any marks.


Here is a before and after pic

 

The air ram is an interesting concept, but I would guess having a way for all that air to exit is key to it working properly. Has anyone tested this on a stock Mk2 engine bay? If you haven't opened up additional vents in the bay it would seem like you would create a high pressure zone around the engine and actually impede air from flowing through the radiator correctly.

That said, I'm in the position now to decide what to do with mine as engine is out and engine bay is being freshened. Seems like opening up the triangular openings would be the right thing to do at minimum. Living in Seattle though extreme temps aren't much of an issue... but still seems like the right thing to do.

 

I think you need a way to let the air flow out. What Clyde did is cool but involves a lot of fabrication work. On my car the simple triangular cut outs are easy, clean and do the job of letting the air flow out of the engine bay.

 

Clyde,


You are a metal master! You have done so many cool crazy work on your Jaguar! Keep up the work as I cannot wait to see the finished car...

 

Living in Austin, I've been battling heat management for awhile. The biggest issue has been vapor lock when the outside temps are approaching 100 F and running the A/C. I've measured carburetor fuel bowl temperatures in excess of 150 F. I think fuel boils around 135 - 140.

None of the standard solutions made any significant difference. Based on the positive comments here, I figured the ram intake and wheel well vents combination was worth a try. Removing the triangular pieces of sheet metal was easy using a cutting wheel. While the aluminum intake ram looks great, I took a simpler route using aluminum angle stock to fabricate brackets that bolt through existing holes on either side of the rails below the radiator. A piece of 1/4" black ABS sheet was attached to the brackets to create the intake ramp. Total cost of materials was less than $15.

The results are pretty impressive: a 10 - 20 degree reduction in fuel bowl temperatures after a hard run with the A/C on.

FWIW, the triangle vents alone didn't make much of a difference.

Here are some (poor) pictures of the installation. The underside of the ABS is very shiny, which makes the picture of the bracket a little confusing.

 

The additional directional pieces Dave created and the way the air is scooped and captured enables the air to go around the full height of the engine then out as I have seen a much greater temperature drop on my car but am glad you have seen a decent drop...

 

Details?

Thanks.

 

Dean- did you do anything other than the scoop? Any vents on the side of the engine compartment, or just use the additional air to flow over the engine, and then back under the car?
I assume you also have an auxiliary fan?

 

Charlie--

I cut the triangle vents into the wheel wells and have a high capacity electric pusher fan on an aluminum radiator that supplements a mechanical fan on the engine.

 

I thought I'd provide an update on this thread.

After implementing several modifications suggested by others, I believe that the heat issue has been resolved on my Mk2. The primary issue was never overheating but rather temporary vapor lock after the car had been run and then parked for 10 - 20 minutes under summer conditions (>80 degrees F here in Austin). The solution was two-fold.

First, the Retro-Air A/C evaporator fan and vent hose routing was completely revamped after I realized it was blocking air from flowing around the engine on the passenger side. Now, there is a straight shot for air flow past the carbs and out through the back of the engine compartment. An added advantage is significantly better air flow through the evaporator.

Secondly, I installed a pair of Joe Curto's SU carb fuel bowl kuzzies and wrapped the fuel pipes feeding the bowls with high-tech insulating wrap.

So far, I've run the car in mid-80s temps with no significant issues. We'll see how she does when it hits the mid-90s.

 

I've made a very similar piece but mine out of steel, painted black. Just a single flat ramp, using the same holes and general angle you have here. It's done wonders, the heat is very noticeably less with my car running hard down the road, barely breaking 70*C. It's starting to get warmer here in LA so we'll see when summer really takes hold.