I think I'm finally going to be purchasing an FD this week. It's got about 83k miles on the original engine and is all stock. I've got ~$500 extra cash to spend on it if I buy it...what would be the best part/upgrade I can buy that'll also help keep it more reliable? I'm thinking a radiator upgrade and new IC piping?

 

radiator and ast or elimination kit. boost and water gauge too.

 

Downpipe and an AST will be close to that budget.

 

downpipe and boost guage.

 

What, new IC piping? Don't waste your money if you can't see any problems with the existing piping.

If the car is definitely all stock then I agree with the recommendations of downpipe and aluminum AST. I'd also suggest a new fuel filter and the boost gauge previously mentioned if they can fit in your $500 budget.

When you have an additional $600 or so available focus on improving the cooling system: aftermarket radiator, new radiator hoses and thermostat, better temp gauge, fan mod, and Miata thermoswitch.

 

I'm not going to add up costs, but...

Boost guage, Miata thermoswitch (or fan mod with water temp guage), DP, Alu minum AST (or bypass), new thermostat, new fuel filter, water temp guage. Also, check the radiator end tanks for discolored plastic. Replace the radiator if it looks bad. After that check every coolant line you can find for brittleness, bulges, and broken braids within the rubber. Replace as nescesary. You also MUST check the FPR and FPD for leakage. If these show any signs of leakage, replace immediately (or you find any signs around the injectors, do the same). You don't want a fire.

I think that's what you really need to keep safe. It's not cheap. You should really have a couple grand more than your purchase price just for any problem that may perk up.

 

BTW, here's some good reading on reliability mods in general:

http://www.rx7turboturbo.com/robrobi...eliabiltiy.htm

I don't necessarily agree with everything they are recommending but this information is good to get you thinking.

 

For 500 bucks, I say radiator

 

The stock radiator is more than adequate for a stock car if it is in good shape.

 

get a cheap daily driver that you can beat the crap out of...seriously.

 

Downpipe, downpipe, and downpipe!

Oh, and did I say downpipe.

This upgrade will reduce your underhood temps by like 200 degrees. Not to mention they clog and ruin the motor and turbos.

Look at the pic in this thread: https://www.rx7club.com/forum/showth...hreadid=227840

It is ugly, and just think yours looks like that or worse!


edit:yes Jonesboro the always popular and never outdated robinette site. Highly recomended.

 

Downpipe, boost gauge, and aluminum AST. IMO these are the most important reliabilty mods you can have. You should be able to score those for around $500. The stock radiator is fine for a stock car as long as the plastic parts on it are in good shape. Check these part distributors for prices:

www.rx7store.com
www.rx7trix.com
www.pettitracing.com
www.m2performance.com