Ok i searched and i found a ton of posts saying that an AST is good for the car. But what i couldnt find is which one. the ones on rx7 store are pettit, and ASI. along with the M2 bypass. My mom might want to get this for my dad, who has a basically stock 93 rx7, for Christmas. I am getting him another reliability mod.

please help.

Scott

 

Pettit's no doubt !! Rotory Performane sells the same unit as well. Installs in less than 10 minutes.

 

cool thanks

 

The ast is nothing more than a container with an inlet (middle/top of the container), an outet at the bottom and an overflow at the filler neck. As long as it is made from a durable material (not plastic), they will all function the same. The rest is just cosmetics. The ASI is a better looking unit (chrome finish) than the Pettit (grey aluminum finish). Functionally neither is better than the other.

 

Just eliminate it!! It's a waste of space IMHO. I'd recommend the M2 eliminator kit. Best of luck.

 

there are tons of AST from Japan, but they cost arms and legs.

 

Pettit.

 

yeah.. the pettit one was easy as hell to install

 

pettit because it looks the best and ask your mom if she will buy me one for christmas as well i need one to

 

eh.. i dunno about it looking the best, i wish it was shiny sometimes

 

Yeah, count me in for a Pettit AST too, Mom.

 

Tri-Point also makes one that looks exactly like the Pettit but since your on the east coast, Pettit is cheaper shipping. The ASI sound tight if it's polished. Oh, Mazdaspeed makes one for 3 or 4 times the cost.

 

I needed a new radiator, and after I got a used OEM one off of eBay for 80 bucks, I told my mom that it was my AST. After much begging, she got me one. Maybe the rest of you should try it... unless ttRx7racer's mom wants to adopt some more kids for Christmas. If that's the case, I could use a 20B. Anyways, I got the ASI b/c I got it for 135. It works fine. Definitely don't even consider the M2 elimination if his FD is near stock.

 

The ASI is actually better. I'm guessing most of you guys saying "Petit" have never seen the ASI one. I've held one in each hand, the AST is totally heavy duty billet contruction. The neck is done much better.

All the aftermarket AST's are better than stock, but the ASI is certainly built the best.

 

The Best AST? Is no AST of course!!!

 

the best AST is the OEM one. maybe its just urban legend but the shapes of the aftermarket ASTs are not the same as the OEM and the OEM shape is better. it's not better in terms of reliability however.

 

are you trying to say that the oem shape is somehow functionally better than an aftermarket? i don't understand how your mentioning of shape and reliability have anything to do with each other...

i've done the elimination, you don't need the m2 kit...
but i'll probably head towards the ASI as well

 

what i'm saying is the OEM AST's shape/design is better than the cylinder aftermarket ASTs, but the aluminum ones are obviously more reliably than the plastic OEM ones. this is what i heard/read somewhere, so it could just be all BS.

 

i'm not trying to pull your cards or anything, its just that if the oem shape was better, why hasn't anyone made a more durable version of that same shape...its not like its patented or anything

 

I had my car dyno tuned today and the guy is like "get rid of that AST, you will be here someday with a blown engine if you dont". He doesn't think it does anything.


I have read the shape of it is very important and that the petit and otherones are just a coke can with coolant in it. when mine cracked I got a new stock one. I keep thinking....why would mazda put it on the 787B? and why would Mazda put it on the RX7 when they went to extremes to lower the weight of the car? I mean, they drilled holes in the brake, clutch petals, they even hollowed out the back part of the wheels. I would think they would not have put the AST on there unless it was needed.

Your damned if you do, damned of you dont!

 

Mazdaspeed does make one look same as the OEM one.

 

go to the RX7 Store and have a look at there options. The answer is obvious, but look at the source of this quote.The only two major differences between the ASIracing one and the Pettit ones are as follows

1. The finish;Pettit's is grey powder coated and the ASI is polished.

2.The filler neck;pettit's is of what seems to be .045 aluminum and the ASI is made from a solid piece of billet. The problem is the thin aluminum neck which has over time become notorious for leaking at the cap due to the thin poor construction,this problem is obviouslly eliminated with the better constructed neck.
To me the answer is obvious

I tried to post some side by side pic sbut if they dont show you or anyone can email for them at; asiracing@worldnet.att.net

 

trying pics

 

i ahve the oem shape ast
and here it is

 

now tell me that doesnt look PURTY
umm ast...