SVX Engine cooling "Again & Again" - Page 105

BackWoodsBob · #**1561** 08-13-2013, 11:50 AM

Seems summit racing has their own brand of radiators now. Cheaper than griffin too.
http://www.summitracing.com/parts/sum-380425/overview/

neverLift · #**1562** 08-13-2013, 11:52 AM

I don't think you understand how a dual pass radiator works...that would just cut off half of your radiator area.

That diagram shows why you need inlet and outlet on the same side. If the outlet was on the opposite side it would be less effective than a normal cross flow.

BackWoodsBob · #**1563** 08-13-2013, 11:58 AM

I do understand. I just don't want to pay another 200+$ for an aluminum radiator if I can just weld in a 1/8th inch aluminum plate to lead the coolant in a way which increases the effectiveness of my rad.

BRZCory · #**1564** 08-13-2013, 12:06 PM

Quote:

Originally Posted by BackWoodsBob

I do understand. I just don't want to pay another 200+$ for an aluminum radiator if I can just weld in a 1/8th inch aluminum plate to lead the coolant in a way which increases the effectiveness of my rad.

It's not your ingenuity that's in question.

It's your welding skills

Well, that and flow calculations based on the number of rows in each of your now 3 cross-over sections, and the cross-sectional area of each.

BackWoodsBob · #**1565** 08-13-2013, 12:10 PM

Welding skills indeed. I can weld just fine thank you much. I haven't however, welded aluminum before and wouldn't be attempting to weld my radiator as my first attempt.

Just saying, I 'could' make my radiator truly cross flow. Even tho the inlet/outlet are opposite side.

neverLift · #**1566** 08-13-2013, 01:24 PM

I must be confused then, where exactly are you welding this plate? Your Griffin rad is already crossflow isn't it? With the inlet/outlet on opposite tanks and diagonal from each other?

cheers
-Evan

BackWoodsBob · #**1567** 08-13-2013, 01:29 PM

Yep, however, if you let the car idle you can feel the outlet tank get hot as hell, as well as the first inch or so of cross ribs. I'm pretty sure it's sold as 'cross flow' and it isn't actually cross flowing. Seems the water is going in, straight across the top and down the outlet tank.

svxfiles · #**1568** 08-13-2013, 02:01 PM

Quote:

Originally Posted by Dessertrunner

I think a addiational issue might be how you get the air out of the engine bay, it appears that a back pressure in the engine bay restricts the air to the radiator.

Is this your findings for an SVX?

I have been wanting a reason to duct the hood.

Dessertrunner · #**1569** 08-13-2013, 05:27 PM

Quote:

Originally Posted by svxfiles

Is this your findings for an SVX?

I have been wanting a reason to duct the hood.

Yes,
Once you fix cavitation the limit on the amount of cooling is the airflow through the radiator.

By the way if you want to run the Fan test idea suggested, with a SVX you need to have the AC turned off or the fan will run.
Tony

bazza · #**1570** 08-13-2013, 06:17 PM

Quote:

Originally Posted by BRZCory

Bob has a legacy, so his engine bay is different. Also he has hood risers on the back, so airflow though the engine bay isn't a problem.

and for what it's worth, my EG33 with a massive radiator doesn't have cooling issues. In fact, after sitting in 100 degree weather in traffic, the fans RARELY kick on. I once did a test last winter, idled the car for 2 hours straight. Fans never came on. Unplugged the temp sensor and they kicked right on (This was just to verify that the sensor was working).

So although I can't speak for high-rpm cavitation, I can say that a bigger radiator will keep it from cooking.

Hood risers at the back of engine won't work like that. This area is high pressure - ever wondered why some v8s have a reverse scoop that enters here to use that high pressure.

BackWoodsBob · #**1571** 08-13-2013, 07:43 PM

When I installed hood spacers I rejected everyone's realities and used my own. Still thinking of yanking the spacers out tho. They do look mean, but my hood pins work better without them. (sorry cory)

Dessertrunner · #**1572** 08-14-2013, 12:06 AM

Have removed

BackWoodsBob · #**1573** 08-14-2013, 12:15 AM

You could make an under-body aero tray that's open at the 'back' of the engine. It would suck air down if angled correctly. Decreasing the turbulence under the bonnet would help a lot too.

bazza · #**1574** 08-14-2013, 02:43 AM

Quote:

Originally Posted by Dessertrunner

Anybody got some ideas on how to decrease the air pressure under the bonnet to increase airflow through the radiator?

Rubber air dam hanging off / below as per many brand new cars. Low pressure created behind rubber sucks air out.

BRZCory · #**1575** 08-14-2013, 04:24 AM

Quote:

Originally Posted by bazza

Hood risers at the back of engine won't work like that. This area is high pressure - ever wondered why some v8s have a reverse scoop that enters here to use that high pressure.

I fully understand this, and that was the "Common knowledge" that we ran into when bob first proposed hood spacers.

So much so that we tested this. http://www.youtube.com/watch?v=yo1hboEl6Qg

We found no evidence of airflow reversion, and I suspect that it has more to do with windshield angle than anything (old cars weren't the most aerodynamic anyway, and there's a reason that they don't use cowl induction anymore).

That being said, there is an easy way to increase airflow, and subaru has endorsed this method:

Although I would be curious how many people have the stock undertray still installed vs who has cooling problems. Another way would be to make sure that there's ducting around the edges of the radiator, forcing air through it rather than around it.