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I am starting this thread to document the installation of a prototype High Performance Aluminum Radiator. I set out to design and have built a custom radiator which would be robust enough to withstand the brutal heat that a Texas summer can bring and still provide sufficient cooling for an engine with a substantially higher power output than a stock 2L spider engine.

The basis of this improved performance is a 2.75 inch thick double pass cross flow design. This is a departure from the standard spider radiator which was a down flow in all the spiders until 1990. The inlet an outlet of the radiator needed to both be on the same side which dictated that the radiator become a double pass radiator. The right tank is a split tank and the left tank contains an added bonus an oil cooler. The benefit of putting the cooler in the tank as opposed to having a separate heat exchange is that you do not obstruct your airflow to the radiator itself and with the increased capacity of the 2.75in thick core there is no worry of taxing the cool system.

These are couple pictures of the prototype that is getting put into my fathers 1978 spider. The mounting tabs are have since been finished since these pictures were taken. I have also have one in my spider which is currently in pieces as I prepare to install a turbocharger.
 

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needs mounting points for puller fan,,
 

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I am starting this thread to document the installation of a prototype High Performance Aluminum Radiator. I set out to design and have built a custom radiator which would be robust enough to withstand the brutal heat that a Texas summer can bring and still provide sufficient cooling for an engine with a substantially higher power output than a stock 2L spider engine.

The basis of this improved performance is a 2.75 inch thick double pass cross flow design. This is a departure from the standard spider radiator which was a down flow in all the spiders until 1990. The inlet an outlet of the radiator needed to both be on the same side which dictated that the radiator become a double pass radiator. The right tank is a split tank and the left tank contains an added bonus an oil cooler. The benefit of putting the cooler in the tank as opposed to having a separate heat exchange is that you do not obstruct your airflow to the radiator itself and with the increased capacity of the 2.75in thick core there is no worry of taxing the cool system.

These are couple pictures of the prototype that is getting put into my fathers 1978 spider. The mounting tabs are have since been finished since these pictures were taken. I have also have one in my spider which is currently in pieces as I prepare to install a turbocharger.
Nice work .....
 

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Sign me up for one . Question, the connections on the left are oil cooler in out then drain at the bottom ?
What are your thoughts on fans ? Pusher, puller ,stock ?
 

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Cost??

Robert Hill in Memphis, TN
 
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Discussion Starter #6 (Edited)
bianchi1: the radiator is thicker than the stock radiator by a very small amount and does not allow the use of the stock mechanical fan. As far as a pusher or puller fan either one can be mounted with through the radiator ties which is what I have done for my fathers. I mounted a pusher fan on the front side of his which is 10 in diameter and with only that little fan the car never really gets above 185 even in stop and go traffic.

Edit: the radiator is substantially thicker but the most of this additional thickness is on the front side of the radiator.

Thanks Cali67Duetto

69alfa: the connections on the left tank are the top two for the oil cooler. They are AN-10 connections. The lower hole could be used as a drain but is just a standard 3/8npt port which I had them put to put an electronic temp sender in. I use this to control an electric fan. I have them put in a port on the underside of the left tank for draining and put a drain petcock in to make that easy. As far as fans go its a toss up for me. Pullers are slightly more efficient but they make engine bay access worse. I think although I have not tried to fit one that a 13 inch fan would fit in front of the radiator which should be more than enough to handle even a 200+ hp beast. I am certain that a 12 in fan would fit. The radiator for my spider I mounted a 14 in fan to the front but let it hang about 2 in below the radiator so that I can use it to blow air through ducts to my front brakes.

vf31rhill: Ballpark 600 to 500 depending on the number of people I can get together. These prototypes were pricey because I had to go back an forth with the company to get it just right and they had to make just two of the custom cores.
 

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I like it. You have thought of about everything, but for Spiders like mine with A/C, use of a pusher not possible due to the A/C condenser out front. Keep my name on your list of possibles.

Robert Hill [email protected]
 

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Discussion Starter #8
I want to show the modifications required to fit these radiators into the car before you guys get to worked up over them. They are not hard changes to make but for those purists out there they will probably be sticking point.

The basic changes required to the car are:

1) remove the cradle that the bottom of the radiator sits in. This can be done by simply drilling or grinding through the 4 spot welds that hold it in place.

2) bend over the rails at the front edge of the radiators slot.

Additionally to seal around the radiator adhesive weather stripping should be used. Also because the fill point of the radiator has moved it is necessary to top off the cooling system via your bleed port to fill it to the very top. This is very quick to to but I just want to make people aware of what is involved.

The pictures I took aren't the greatest but they give you and idea of what is required.
 

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Discussion Starter #9
Robert. I think there should be enough room for most slim puller fans to be mounted to the radiator on the engine bay side. I can measure on my fathers spider sometime later this week and let you know the clearance to the water pump and crank pulley. I know Spal makes a very nice slim fan that should fit.
 

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Discussion Starter #11
Robert:
I apologize for not getting back to you yet with clearance between the water pump and the radiator. I ended up getting tied up with work and am just now getting back to things with cars. I will check the clearance tomorrow and post.


For those interested in a radiator. I will be asking for firm commitments at the start of May. I will also need half the cost upfront when I put the order together at the start of May. I expect, that if the order goes in at the start of May, to have the radiators in hand sometime between the 3rd week and last week of May.

Current price 550 + shipping (based on having 5 made)
I have been told that if I they make 10 they will give me a 50 dollar break in price.
 

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I've had some recent experience with electric fans that I can pass on. Perhaps having 2 L engines provides an entry.

Two nine-inch curved-blade pushers were mounted on my Spider a few years ago. Our return from the Mount Hood tour at the Portland Convention was a quiet drive down the Columbia River. It was hot and at 50 mph the flat fan blades restricted airflow such that coolant temps went up--enough to trigger the fans. Interesting but absurd.:p

This and the shrill whine of the curved blades prompted a review.

Spal has a 5.2 inch puller fan with paddle blades so I installed two at the top of the rad. These are aft of the cross-frame in front of the rad so they are pulling otherwise dead air--leaving more area for the natural flow.

Have them on my Sprint which got out of restoration this week.:D

The advantages are that curve-blade fans have thin motors that present a large blocking area compared to the smaller and thicker boss of the paddle fan.

Paddle blades are quieter than curved blades.

Two 5.2-inch paddle fans weigh 3 pounds. Two curved ones weigh 9 pounds.:cool:

Spal is an Italian company.;)
 

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Alex.
What is the present status of orders? how many and can I still get one .
Please send details on ordering and delivery.
thanks
jim
 

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Discussion Starter #15
Right now I have 4 people who have said they will be ordering one. I will be asking for half the price via PayPal at the start of may. Once I have received everybody's payments I will put the order in. Based on the turnaround time on the first two prototypes I expect to be sending the radiators to people between 3 and 5 weeks from the day I put in the order. Just let me know if you are interested. I will be sending out PMs sometime in the first week of May to those who have expressed interest.
 

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Alex
I want one. send me the PM when you need the cash.
I would love to here more about performance of the 78 spider on temp before and after installation.
regards
jim
 

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Alex,
I also have a 78 Spider but notice that your fathers' car has nou air pump as is required on my California car. So I will try the 10" pusher fan you fitted to your dad's car. can you give me sourc and type,cost, and how you wired and control it so I can start gatherin the bits.
Thanks
regards
jim
 

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Discussion Starter #18
The fan controller I used is a

Derale Cooling Products 16749 - Derale Performance Deluxe Adjustable Controllers with Pipe Threaded Probes

It has a 3/8npt temperature probe which is the fitting I have at the bottom of the driver side tank. The wiring for the fan was done based off the instructions for the controller which can be set to switch the fan on at almost any temperature. As for the fan itself. I used a 10 in SPAL pusher fan I bought off of ebay. Depending on what other components you have in front of the radiator you can choose a more appropriate fan. It most likely would be possible to put a 11 or 12 in fan. The cost doesnt seem to vary much with size so i would suggest waiting to purchase the fan itself until you can measure the fit in your car. That said the the 10" fan combined with the improved cooling efficiency seems to be capable of keeping my father's spider's temperature locked in at a cool 185!
 

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Thanks for the info Alex,I bought the bits last night including a 10"SPAL paddle blade pusher @ more than 1000cfm so I should be ok.
My car has been running at 196 even in cool weather since I warmed up the engine with the total rebuild .With the big valves,11mm cams, 10.1/1 pistons,and lighter flywheel she revs fine but runs hot. Am very glad you have done the work to get the temp down and make summer driving in Napa not so nerve wracking.
regards
jim
 

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Doesnt Ron Davis have a developed one already? Know they do for 67 GTV's and you can add a heat exchanger to it as well...
 
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