cobra cleanup

[The Fab Ford]

Forgive me for my ignorance, my first Cobra customer is going to drop a car off to me this sat morning and I have a question about radiators. I have a small sole proprietor fabrication shop in Watsonville ca and have been building street performance and open track Mustangs and Cougars for 6 years. I am a competant fabricator/welder and am comfortable with taking on a Cobra but I just need to get more familiar with the aftermarket hardware that will install the cleanest and not compromise a period correct theme. The owner bought the car off of Ebay and immediately had an engine knock and what sounds like the loss of a cylinder. I listened to it, and the first thing I noticed was inconsistency in the starter speed like when you crank an engine over with one spark plug out. I started it and immediately noticed a very poor throttle response followed by a knocking and turned it off. The car has a 308 stroked 351 built in the mid '90's with a 400 crank and rods, world product heads and a roller cam of mild duration. He told me that the person that sold it to him said "go ahead and spin it up to 8000 rpm and if you hit 8500 for a short blip by accident, don't worry she's built to handle it" OH MAN, I thought here's the start of his problems. No cam with less than 225 @.050 duration needs to go there, plus its a hydraulic roller. My experince with hydraulic rollers is that if you want big spring pressures and or high rpms you need to go solid roller because hyd roller lifters were never designed for this kind of abuse. So my first thought is he probably has eaten a lifter or two which could mean destruction of the cam and potentially a liffer bore also. My thoughts are if he has this little knowledge of how to drive this kind of hardware, I better get rid of the Duraspark ignition and put in an MSD with a 6500 rev limiter, this will keep the rpms down to something that a hydraulic roller and a set of long 400 rods can deal with. He also complained that the guys at the local muffler and radiator shop were unsuccessful in stopping an overheating problem, they rodded the radiator and repaced the hoses and thermostat. I took one look and he has what appears to me to be a 1969 351 Windsor with AC (27"core) radiator with some poorly fabricated tabs to hold it to the chassis, the rad is laid back with the top towards the motor such that its so close to the steering rack that they couldn't fit an electric fan that would shroud the entire core and so put a small electric pusher fan on the front. The real eyesore was that they put a cheap autoparts store flex fan that points more at the top tank than at the core. This is where my main questions start for you Cobra experts: All of this is going to come out, I want to install a dual puller fan assembly to the back of an aluminum thermal disspersant coated radiator and remount the assembly so that it clears the steering rack. I have seen pictures where it looks to me like the radiator tips to the front of the car at the top instead of towards the motor. Also since I dont have the surge tank on a 351 like on an FE motor, I would like to get away from a top tank radiator and go to a crossflow. So my question is....

what company makes the cleanest and simplest to install crossflow radiator, Griffin, Fluidyne, Howe etc etc?????????

Next, are there any brackets made that tilt the top of the radiator forward, or do I need to fabricate them? and due to body profiling is this an option?

Lastly, does anyone sell a kit to install an airbox to direct airflow from the front body opening to the radiator or do I need to fabricate this also?

Any pictures of radiator installs would be helpful

OK i had to come back and edit, after surfing around i saw body off pics and it looks as though the chassis tubes wouldn't permit any other angle of the radiator , so I'll probably just have to figure out how to bracket it farther forward but at the same angle.

Thanx,
Tom

[cobrajeff]

Tom -

Good luck on your new project.

You're right about the guy needing an MSD with rev control - I sure don't think that sounds like a combo that would rev "comfortably" to "8,000 rpm" - I don't think I'd be comfortable spinning it much past 6500.

One of the first things I recommend you do is to try to determine the manufacturer of the kit. Some of them have a clue in the VIN number (my ERA has a VIN # like ERA XXX; Contemporary kits usually have a VIN # CCX XXXX; etc.). Though there is a great deal of similarity of appearance, you will find that there is not much interchangeability between different kit manufacturers. If you know the kit's manufacturer, then you can review the forums on clubcobra related to that kit maker for specific info on what parts may or may not fit.

The shrouding from the nose to the radiator will probably have to be custom made, as well as brackets to mount the radiator in the car. This shouldn't be a major task, but might be a little time-consuming. You might also consider adapting an expansion tank to the system - there are other tanks available, like the round aluminum Harrison model used on 289 FIA cars, and the flat with rounded top early FE one from early 60's T-Bird, similar to a 289 street car model. Either of these can be remote-mounted to the fenderwell or spring perch, instead of having to directly interface with the intake manifold water inlet.

I can't make a recommendation on the radiator, but I think all of the brands you mentioned should have a model that would be close enough. Here a few places I would recommend to you for chasing Cobra specific parts:

Finish Line, Inc., Pembroke Pines, FL. (888) 436-9113

Operations Plus, Santa Ana, CA. (714) 962-2776

Cobra Restorers, Kennesaw, GA. (770) 427-0020

All of these suppliers are familiar with both original and replica Cobras. If you are able to determine the brand of the kit you are working on, they may even be able to recommend parts that they know will fit that brand.

regards,

cobrajeff

[The Fab Ford]

ahh, thanks Jeff
I spent so much of my brief visit at his house talking about the motor that I didn't even ask the kit manufacturer lol. But because of certain design characteristics i think its an FFR. After I left i figured I'd get the details once it appears at my door. I did see a few nice examples by looking through member pictures and have found out that the 87-93 mustang crossflow is what FFR uses. Heres a picture of a set up I liked. http://www.erareplicas.com/427man/cooling/radretro.htm

I also looked at a picture that made it all clear to me now. This is an unpainted canvas, each car shines by the creativity of the fabricator. Well I guess I'll just put my favorite artists cap on and get busy
Tom

[badrich]

Tom: After I installed my new motor, I had some overheating problems when I got caught in traffic. After dinking around for a while, I ended up getting a custom shroud fabricated around my puller fan and I dumped the coolant in favor of Water Wetter and distilled water. No more overheating problems! Rich

[The Fab Ford]

Originally posted by badrich


.. getting a custom shroud fabricated around my puller fan and I dumped the coolant in favor of Water Wetter and distilled water. Rich

Thanks Rich
Thats why I want to relocate the rad, I want to install a dual electric with integral shroud that pulls from the cores corners. I have to get it clear of the steering rack first. And yes to the water wetter, I'm already a fan of that. I found a late model Mustang crossflow and a 351 designed surge tank at one of the sites Jeff posted, so I think I'll have a decent presentation of my solutions by the time the car gets here. Attached is a pic of a fan set up I used on an open track trans am style 67 Cougar I just finished. Cosmetic resto on that one starts next spring.

Ok, I found out what kit I'm dealing with, its a CMC kit out of Florida.
The owner talked it up as one of the nicer kits available but then I wonder why they're not making kits anymore?????

Tom

[Jack21]

Tom,

Selecting a radiator and fan shouldn't be that difficult. Allthough all manufacturers use unique approaches to cooling, most of the Mfg's are below in the Mfg section, and all will advise you on which rad and fan to use. FFR uses an OEM Mustang assy.

That being said, if the engine is pumping air into the cooling jacket from a head gasket, head, or block, then not even a diesel truck rad will cool it. Fix the engine first, then the owner, then the radiator.

[The Fab Ford]

Originally posted by Jack21


Selecting a radiator and fan shouldn't be that difficult.FFR uses an OEM Mustang assy.

Yes this is what I'm learning, I'm thinking I'll be using the 87-93 Mustang radiator from Griffin, I'm not worried about how well it will cool because with a good fan set up this ill be plenty for a 408 small block. I was more concerned with getting a radiator that will have the best architecture and frame work on top and bottom of the core to make fit up and adaptability to brackets the best for this chassis. But now that I have been looking around I see that most everyone starts with radiators that have no particular Cobra specific attachment brackets and fabricate it all themselves. The one method I'm interested in though is the center button sytle in this link http://www.erareplicas.com/427man/cooling/radretro.htm
I'll have to advise Griffin to add the weld on bolt boss for this method

[trularin]

Griffin are very nice and appear to have better thermaltransconductance properties. I have one in my car and have not over heated. I tried a brass unit and the fan ran nonstop.

You can ask them to make any radiator you want, they will make it. Actually, unless you are set on fabribating a shroud, I'd do an aluminum Rad with either dual fans or a single 16" and see how the heat is in city traffic.

If the engine is making all that racket, what does the customer what to do? If you said, I am sorry, I missed it.

Just my $0.02