Damnit! I just noticed that my car hasn't had an Underbelly Tray... I mean I didn't even know that I was missing one, until I was reading about following the advice of other forum members regarding rigging additional ducting for the radiator.

I've had two motors fail due to bad coolant seals over the last seven years. Now that I am actually paying for Pineapple rebuild, the last one was under warranty, I am looking to make sure that I take all the neccessary steps to avoid this happening again.

What I can't beleive is that ot one of the mechanics that have worked on my car in the last seven years didn't even mention that I was missing this thing! I had to read this post (https://www.rx7club.com/forum/showth...ght=underbelly) to find out that it was a crucial part of the cooling system. I bet some shop that did work on my A/C or radiator(s) either forgot or was too lazy to put it back on...

Damnit!

Ok, So I need to buy one...Anyone got one of these for sale?

 

I got one from RX7.com (Rotary Performance). You'll have to call them though, it isn't on the www site. Mine was all beat up so I replaced it. Can't remeber the price but I thought it was a bit pricey at the time. Pretty sure it was sub $200 though.

I would get one asap. I also didn't have the clips for the back so I used some zip ties and it works fine.

 

i picked one up thru mazdaformance for less than $200 shipped, including all the little screws that secure it

 

Talk to some of the local mechanics in your area.... I'm sure that other customers had their underbelly tray left behind. Just ask for one that hasn't been claimed
Shouldn't be more than $50- $100 that way.
All sorts of stock parts get left behind @ shops

 

Good Idea Rotor-rooter. I'll try that before I spring for a new one. Malloy has em for 125.00 w/o hw.

 

How the hell does a piese of plastic keep your engine from blowing??? I've thrown 2 of those things away...

 

It lessens turbulence through the engine bay as it was designed to do, which allows more air to flow through the IC and radiator. It also quickens air underneath the car.

 

I don't believe you undertray would cause you to have bad seals...the ducting would only provide extra cooling...If you have an aftermarket temp gauge and have been watchingit closely, and you have not been overheating constantly, I really don't see how that could have caused it...The undertray will help with channeling the air to the right places though.

 

Well, if you consistantly ran hotter, especially for several years, because the pan wa not there, it would probably shorten the coolant seal life.

 

Almost no air flows through the radiator if you don't have the undertray. It is a MUST HAVE piece. It will do more for cooling performance than any aftermarket radiator.

I had to prove it to myself. I had removed the undertray to run it to a shop to have some work done. 60 deg ambient temps, steady cruising speed, the temp reading on the PFC continued to rise to 94degC when the fans kicked on. Temps then went down to below 90degC. Temps would then climb again until fans would kick on, cooling it down again. Normally the temps would have stayed at about 81degC, the thermostat temp. This is even with the CWC dual oil coolers and Fluidyne radiator.

The undertray missing alone shouldn't take out your seals but cooling is a very iimportant factor in the longevity of our cars. You absolutely should not remove it from the car, and especially don't throw it away!

Mark

 

I just ordered one today from Malloy Mazda. 120 bucks shipped. Just search for their number on here. I talked to Ray. Awesome guy to deal with.

-ray

 

I'll probably get one from Ray @ Malloy if I don't find one used. My motor is a 3-4 weeks away from being done.

 

It is a bad idea to run without the under belly pan. Basically the fans will have to do all the work to keep the motor cool. I've seen cars run without it, 50-60F outside and the fans are always running.

You WILL CONSISTANTLY run hotter without that tray, on a FD that is not a target to aim for.

 

I'm glad you're getting the belly pan, but how could you not notice in seven years of owning your car?

 

Ditto. This is also one of the main reasons I started working on my 7 myself. Aside from places like KD Rotary and RP, I never trusted my 7 at random garages or Mazda dealerships.

 

No ****. Come on, I already feel stupid.

I just never knew that it was supposed to be there. I also never saw on one anyone else's car either. I also just started "working" on my car in the last two years. Basically, when I "found" this Kick-*** forum.

Before finding the rx7forum, I didn't even attempt to change my own oil....LOL I actually PAID someone to install an RE Amemiya Intake(can you say, "ubernoob") five years ago.

Life after discovering the forum has been fun, and really expensive....Modding an RX7 is like being hooked on Crack...

 

Sorry, I didn't mean it like that. I'm just stunned.

But since you don't know how long it's been off the car, why not call the shop(s) that would have had to remove it to do some work. Might save you some $$ if it hasn't been too long...

 

Hmmm, maybe I should put mine back on. The only thing is the fans are going to blow right into it if i do. I don't think that would help cooling for me very much.

 

My car was a Florida car and heated up badly. Turns out it was the front mount intercooler blocking all the air flow. I did have the undertray, but I removed it one day to see if it changed (hotter) and it didn't. I would typically run 220-230 degrees, but since I switched to the stock intercooler, I seldom go over 190 even on hard turbo runs.

If you run FMIC, you should also stand your radiator straight rather than lay it down at an angle so air can flow through the radiator and the IC. The underpan would be effective again.

Also, stay away from that orange coolant stuff. I heard it does bad things to a rotary... I don't mean Evans coolant, either (I have no idea what color that is).

 

With the V-Mount you will probably be ok if you don't have a vented hood. The air being crammed into the hole in the front has to go somewhere and most likely the easiest path (with stock hood) is through the radiator. Just make sure you block up any holes so the air doesn't just go around it.

 

No Joke, especially about the expensive part!

 

Yeah Scrub I think you'll be okay since you completely redisigned the flow of air through your intercooler and radiator. Basically the undertray pushes the air up into the radiator which is angled like this \

Your radiator is angled like this / so the undertray really wouldn't help air flow into the rad

EDIT:

OH, BTW jpandes...I have an underbelly you could have. Let me know the cheapest price you find and I'll beat it by $20.

 

i tok mine off when i had to reolace the lower radiator hose, so i should put it back on?

 

Sounds to me like you need to put it back on asap.

 

Roger that, Lightfighter.