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brontosaurus
07-30-2012, 10:54 PM
There are a couple of these for sale here and there for our engines. It's a relatively cheap "upgrade" in theory, but is it worthwhile? Everything in front of the radiator seems like it will heatsoak eventually. Anyone have any practical experience with these?

Phatmiata
07-30-2012, 11:07 PM
have a photo of what you are talking about?

SM16RMSM
07-30-2012, 11:24 PM
It like a wooden spacer that goes in between the intake manifold and the engine so the heat doesn't transfer to the intake. Some say you can drive a car around for a hour and still touch the intake and it will be cool to the touch, not hot. They started making them out of wood since it fairly cheap and was a major improvement on carburetor cars. The fuel in the bowls doesn't get hot and it made a carburetor car run more consistent. I not sure if it would make a major different but I assume the air temp will be lower and the Miata would make a little bit of extra power. They didn't really take off. It was just a spacer in the beginning. It was aluminum to raise the carburetor up. Soon after they where made in wood and plastic versions. Wood was better to own since it would last longer and it was also better in blocking heat transfer so it ended up being something to block heat to the intake or carburetor. Some people seen it as a way to lower air temps since the lower the temp is, the more power a engine makes. It was so popular with drag racing that NHRA teams started using them just so they could gain that tenth of a second. It was that big and just about everyone was looking to get one. My father and I sold them at your speed shop a few years ago before we closed the business in 2010. In theory they work pretty good. I think it would be a nice addition to the motor but placement of the intake further away would be an issue then with our cars. I also never seen one for our motors.

etikoner
08-06-2012, 07:42 PM
949racing.com sells em for around 50 bucks plus shipping.

Hondata makes them as well as some other companies. Would really help with air intake temperatures...

SM16RMSM
08-06-2012, 08:41 PM
U mean this?

http://949racing.com/Hondata-Intake-gasket-Miata.aspx

I always thought it was just a gasket. I always overlooked it. Cool, now I know when I pull the head.

I<3flippyheadlights
08-06-2012, 09:00 PM
A friend in the local club has one on his NB. Holy crap, are these things awesome! He turned on the car and we began to talk. Half an hour later (ya we talk that long) I put my hand on the intake manifold and it was cold. It was so amazing!

Soledad
08-06-2012, 09:28 PM
Seriously? I've been kicking around the idea of getting one and installing it with my freshly powdercoated manifold. I'd like to hear a few more impressions of it before I pull the trigger.

revlimiter
08-06-2012, 09:34 PM
Do some research on "resident time" that the air charge spends in the cylinder. I'm not convinced the spacer would do anything good. Much like insulating the crosspipe on an intake... air just doesn't stay in there long enough for the chamber walls to really heat it. It's being heated by the engine itself and then it gets drawn into the filter.

Ciotti
08-08-2012, 12:28 PM
Beware...

http://forum.miata.net/vb/showthread.php?t=363329&highlight=phenolic+spacer


There are many more threads over there, do a quick search and you'll find them.

concealer404
08-08-2012, 01:31 PM
Do some research on "resident time" that the air charge spends in the cylinder. I'm not convinced the spacer would do anything good. Much like insulating the crosspipe on an intake... air just doesn't stay in there long enough for the chamber walls to really heat it. It's being heated by the engine itself and then it gets drawn into the filter.


This.

They won't hurt, but don't expect much real-world difference. It IS something else to put in your mods list, though.

WestfieldMX5
08-27-2012, 03:02 PM
I had one on my '94 a couple of years ago and they indeed work very well to keep the intake manifold cool. I didn't see any power gains though. The only good thing about them is that you could install the air temp sensor directly in the intake since it doesn't heatsoak as much.