are these for air flow or just to keep crap out?

yep, you definetly need those. helps direct air to cool the engine.

If that's the bit that goes just above the shift linkage on the HEs, no, you don't really need them. If you switched to a header in place of the HEs, that piece would vanish. I'm sure there's some marginal effect on cooling, but it would be pretty small.

Well

Went to True Value, got 6M allen screws and put them back on. Took a shower and I feel better

90+ here today, under a car that ran today, it was HOT.

But my car is ok, so I am

QUOTE (grasshopper @ Sep 10 2005, 02:25 PM)

yep, you definetly need those. helps direct air to cool the engine.

QUOTE (qa1142 @ Sep 10 2005, 02:23 PM)

are these for air flow or just to keep crap out?

There to keep crap out.

Actually, they restrict air flow, and hold heat.

Think about it, fresh air comes in the engine cover, drawn by the fan, pushed thru the shroud, into the head tin, which directs it to the heads and cylinders, and exits out the bottom, till it hits all the sheet metal on the bottom, which it's designed for the air to flow to the rear.

With out all that tin underneath, the cooling flow is unobstructed, so no back pressure, no back pressure on cooling is good.

On the ass engine A/C krautmobiles, VW, Porsche, that tin is pretty much all there for a good reason, it is not like they did not think about it in the 50 years they have been making them. Running with parts missing can be pretty bad.

put them on. they really help keep the engine cleaner and protect it. they also are a securing point for the head exchangers to the case.

k

OK Mom

they are on already !!!!!!!!!

QUOTE (Tobra @ Sep 11 2005, 08:05 AM)

On the A/C krautmobiles, VW, Porsche, that tin is pretty much all there for a good reason, it is not like they did not think about it in the 50 years they have been making them. Running with parts missing can be pretty bad.

Do, 911 motors have all that tin underneath them?

And in 50 years they couldn't get more than 90 HP out of a type lV, so they cheated and just added 2 more cylinders

QUOTE (V6914 @ Sep 11 2005, 02:37 PM)

QUOTE (Tobra @ Sep 11 2005, 08:05 AM) On the A/C krautmobiles, VW, Porsche, that tin is pretty much all there for a good reason, it is not like they did not think about it in the 50 years they have been making them.  Running with parts missing can be pretty bad. Do, 911 motors have all that tin underneath them? And in 50 years they couldn't get more than 90 HP out of a type lV, so they cheated and just added 2 more cylinders

They could get plenty more than 90 out of them, but they wanted them to run for a few hundred thousand miles. Their are aftermarket pieces of tin to go around bottom side of cylinders for the type I, haven't had the 914 long enough to be intimately familiar with how it looks from a supine position. I never worked on a 911 but don't they have like a 12 quart reservoir and a remote oil cooler? They set the fan up different too.