Radiator duct work

Looking for help with radiator duct. I was thinking of blocking the open area next to the radiator to force the air towards the radiator but I feel like a flat sheet of aluminum won't be enough. The cardboard is just for reference.

That would be a great start.

Could also just angle it out from the radiator forward to the grill and  leave some air free to get back to the headers/engine for some airflow that way if you want.

Best thing you could do is make sure there isn't anywhere for air to go other than through the radiator.

If you're not looking to do that much then at least block off what you have with the cardboard and add an air dam to the bottom of the radiator/core support to catch passing under the car and spill it up in front of the radiator.

+1 for angling it forward, be careful about blocking off all airflow into the engine bay though, often people over-optimize airflow through specific things in a production car's engine bay while reducing overall engine bay ventilation, which leads to finding out which parts were relying on air passing through the engine bay the hard way, when surprising things melt or otherwise overheat...

Perfect I would just do half of the opening and and angle it towards the radiator and leave the other half open for the engine bay flow 

Why would that cardboard help? Seems to me all it will do is stop the flow to the rest of the engine compartment.....

I think the only useful additions would be to close off any air escaping around the sides or top/bottom of the rad. IOW a short chunk of something attached to the open right side and going forward, and making sure the left side , and the top and bottom are closed off the same way.

MiniDave said:

Why would that cardboard help? Seems to me all it will do is stop the flow to the rest of the engine compartment.....

When presented with a restriction, airflow finds the path of least resistance.  Which in this case is around the radiator rather than through it. 

There are two reasons to block it off:

1) Better cooling efficiency

2) Better aero through less underhood pressure.

But yes, there may be side effects with underhood temps.  This is why people typically vent the hood along with restricting air into the engine bay.  Pushing that air out under the car works but creates lift.

Came up with this. Will find out next weekend if it made a difference. 

Andy Hollis said:

MiniDave said:

Why would that cardboard help? Seems to me all it will do is stop the flow to the rest of the engine compartment.....

When presented with a restriction, airflow finds the path of least resistance.  Which in this case is around the radiator rather than through it. 

There are two reasons to block it off:

1) Better cooling efficiency

2) Better aero through less underhood pressure.

But yes, there may be side effects with underhood temps.  This is why people typically vent the hood along with restricting air into the engine bay.  Pushing that air out under the car works but creates lift.

Also, lowering the pressure underhood moves more air though the heat exchanger. Airflow is powered by pressure differentials, too many people forget that. Gotta let it out, not just jam it in :) 

Venting out through the hood can help combat lift on the front of the car that is a result of low pressure on the top of the hood. That also helps drive the vents, win win!

chiquito1228 said:

Came up with this. Will find out next weekend if it made a difference.

How will you know "if it made a difference"?  What are you measuring? 

You never said why you were doing this.  Are you have overheating issues?  Looking for lower IATs?