"I did some tests with the nylon spacer and found out it reduce temperatures at the end of the runners by as much as 20 deg. this is huge. The plenum temperature droped by 10 deg. This was with a cultus manifold. Since the stock swift manifold has the CIV almost embeded into the plenum, I suspect temperature difference to be even greater with a stock swift unit.
The test was performed with the engine idling for 30 mins. Fan kicked in a couple of time, just to make sure engine temperature were the same as when you are waiting at the red light.
With the cultus manifold and steel gasket, I got a average reading of 91deg at the base of the runners with the laser pyrometer.
This is the reading I was getting at the plenum.
I teared the manifold apart and started the install. First thing you need to do is to enlarge the holes a little bit to make room for the nylon insulators
I can't push enough the fact that any aluminum surface must be decked to insure its flatness. Look at this flange after I got it decked for a few seconds. you can see it was seriously warped as only the center of the flange has been sanded. It will take several passes to bring everything back to normal. If you don't want a leak, bring your manifold at your local engine shop and have it decked. Don't forget to clean it up carefully before puting it back.
Here are the nylon insulators. Those have a nice shoulder that will keep the bolt from transfering heat to the flange. Note that the manifold will be 100% electricaly insulated. You will have to make sure the grounds that usually thread into the intake are relocated elsewhere on the head or you will have severe electrical issues.
It's mandatory to use a sealant to keep leakage away.
My favorite brand is the gasket eliminator 515 from Loctite. This is a special anaerobic sealant, meaning it will only dry and harden where there is no air.
time to reinstall the manifold, slide in the nylon spacer into place before tightening everything.
Same thing with the CIV spacer. Note how different the cultus design is. The CIV is held much farter from the plenum than on a stock manifold, creating a lesser warm spot than the swift one. The spacer will make a even greated difference on a stock swift intake.
When everything is done and said, it's time to check the efficiency of the spacers. Here is what I got at the base of the runners after leaving the engine to idle for 35 mins (fan kicked in several time also)
And finally..the plenum
The difference is incredible. you can put your hands anywhere on the intake, it will remain cold. Now try to keep your hand on a stock swift manifold with the engine idling for 30 mins. good luck!"
Whaddya think? Upgrade worth considering on a v6 or BS?
I guess only benefit would be in traffic, since at WOT plenum, runners etc, have temp. pretty much close to ambient on a N/A car.