The insulation material under the hood of my base model '88 RX-7 is pretty sad looking. small portions are missing. Lager portions are have lost the grey "top fibers" and are down to the yellow fiberous material. I am contemplating removing the insulation entirely. I have two possible concerns however; 1) Will the intense heat from the 13B kill the paint? (not that the funky color re-spray the PO did is that fantastic anyway) 2) Does the insulation have any fire suppression qualities (if so maybe I should leave it).
Any thoughts?
Thanks,
Ray
I took the underhood insulation off of my '89 for the same reason (it was coming apart). I ran it that way for over a year with no ill consequences, but to be fair it wasn't a daily driver. YMMV.
In reply to CLH:
Thanks for the info. My RX-7 is not my DD either.
1st Gen RX-7's didn't even come with underhood insulation. If mine won't burn the paint, nobodies will.
I got involved in a long and stupid argument on a BMW forum about removing hood insulation. The short answer is this: it has nothing to do with paint protection. It's there to quiet noise, period. Removing it will have no ill effects unless engine sounds bother you.
I remove this from every car i buy. Makes the hood heavier, and i always tear it somehow. I've never had any issues with paint, and as a bonus, you can see steam off the hood when it rains. Looks pretty cool.
As stated it is for noise and vibration duty only, the fireproofing is so the insulation won't catch fire, remove it.
I removed the insulation from my RX-7 a few years back. Even with all the glowing hot twin turbo cast iron under there it hasn't affected the paint that I can tell.
I am not the original owner of my 88, but there ism't any insulation under the hood, and no evidence that there ever was any!? But there is also no paint damage after 5 years of V8 generated heat.
I removed the insulation this weekend...looks much better. Thanks!
-Ray
scardeal wrote:
I need to do this!
How much do they weigh?
It weighs 1 lb! lol
Also add an aluminum hood to save more weight if you haven't already.
Slightly off topic (lol)
Any of you guys use Seafoam on your 13B rotaries? Mine is a '88 non-turbo with 120k on it and a local guy said I should do it if it's never been done.
In reply to fornetti14:
I heard of people using that to clean out their engines.
Take off a vacuum hose and fill it through there while running and get ready for lots of smoke!
You can also use some ATF through your spark plug holes, I hear this losens the carbon build up.
junpower wrote:
In reply to fornetti14:
I heard of people using that to clean out their engines.
Take off a vacuum hose and fill it through there while running and get ready for lots of smoke!
You can also use some ATF through your spark plug holes, I hear this losens the carbon build up.
ATF can also eat away at apex seals, so I wouldn't use it except as a weapon of last resort for engines that won't turn over.
In reply to RexSeven:
If you use it constantly, yes, but we are talking about one time to help clean the inter-engine deposits.
I have seen engines with stuck apex seals, and using ATF actually helps get them lose and working again.
Also, all proper rx7 owners use some 2-stroke oil with their gas 
A little kerosene down the intake on 70s and 80sV-8s used to clean out the carbon, and control the summer mosquito population, too.
A little kerosene down the intake on 70s and 80sV-8s used to clean out the carbon, and control the summer mosquito population, too.
