XalD

I was looking to get into an FD for quite some time now, ever since I got my RX-8 basically, and I've since been between how important the engine age and condition is if I'm planning to do an engine rebuild anyways (looking for 300ish WHP)

Essentially what I'm saying is are there any components also likely to fail at relatively high mileage (say just about 100k) or is it just really the engine at that point? Should I be looking for an absolutely beautiful car or is good body and interior condition enough if I'm doing a build anyways?

CrimsonPride

iTrader: (11)

A lot of things will wear out within that mileage: turbos, LH outer door handle, transmission output shaft pilot bearing (necessitates almost complete disassembly of trans), pillowballs in rear susp just off top of my head. I'm sure others can add more.

XalD

So what would you say the maximum mileage I should look for on one is?

CrimsonPride

iTrader: (11)

Hard to say on the mileage but I would buy the nicest, lowest mileage one I could afford. 300 whp goal should be achievable without porting so an engine build is not a must for that goal. FD does great adding HP with bolt ons. Stock is about 210 whp and you can add the first 35 or so additional HP with DP, cat back, and intake or airbox mod. I would just do as much reading on this site as I could. I'm not yet where you're trying to go HP wise so I won't presume to try to tell you everything but your goal is modest. In fact, Fritz Flynn has a big writeup in the archives on modding and says that he thinks that low 300s whp is really the ideal HP level for an enjoyable and reliable FD. Most of the info you need is already here.

Possible you could find good value in buying one that needs an engine build. And, there are some FDs that need engine builds at lower mileages from the neglect of owners and their FD being a second or third car that they didn't put much mileage on. Just depends on your budget and what's out there for sale.

XalD

Alright thanks, yeah I've read quite a few places FAQs already so I'm pretty set on a lot of things... Just couldn't find much info on other likely things to fail at say 100kish

I read the reliable 300hp post a week or so back which is kinda what helped me decide on doing about there as a goal.

My final thing for this this which I know has been covered countless times but it's difficult to pull much useful from the threads is what seals to use for a rebuild? At only probably 12-15lbs is it a good idea to just stay OEM? Most of what I read seems to point to that but I just wanted to get some more opinions.

CrimsonPride

iTrader: (11)

12-15 lbs of boost based on my reading it seems that you would not reach the limit of the stock apex seals. Again based on my reading, I have heard that you reach what is a safe boost for the reliability of the stock TTs before you are limited by what the apex seals can handle. I think there are people on here who are using the BNR rebuilt TTs to run even higher boost but still have a stock engine build. I can't remember specific posts but that is the impression I'm left with from my overall reading on the site. But you could look specifically for info on apex seals and boost level. The apex seals seem to be the first limitation as to boost for the engine internals. You will reach the limit on the stock ECU and fuel system before you get to that.

If you are having to rebuild anyway though, I'm not sure about what is the best option on the apex seals. Probably expensive and overkill to go 3mm but there are some other differences in the apex seals available as well. I don't have the experience to cover that but I see posts about the stock 3 piece vs. other types. Some use different coolant seals, like teflon but that isn't a boost/compression issue.

XalD

From my reading it seems like using 3mm can cause issues because the rotors have to be machined to the size to fit them. Not sure how good that is for the rotors, not to mention I'm not running any kind of rediculous boost, so it may just be overkill with the need for pre mixing oil and additional lubrication.

Sgtblue

iTrader: (16)

Otherwise well maintained FDs on stock twins and no history of serious overheating will statistically still eat a coolant seal at about 100k. That requires complete disassembly, so a complete rebuild usually coincides. The ultimate price of that rebuild is based on the internal condition of the other wear parts like housings, irons, bearings etc. If the car hasn't been neglected or abused, usually housings and irons are within spec. Hard seals and springs IMO are kind of a no-brainer regardless. Porting is optional but if you don't have emissions to worry about I'd consider a street port but nothing more for a streeted car.

I've never had my car on a dyno and it was built with reliability and longevity in mind. I'm old, it makes enough power for me, and I'm not concerned with numbers. That said, two different guys who know a lot about these cars and whose opinions I respect have estimated my car to be close your whp goal. So if you decipher my signature, you'll have a good idea of modifications that would get you close.

Dreams_of_Rotary

If 300hp is your goal than you would not have to have a ported motor. Upgrade to a supra or walbro fuel pump, intake, downpipe, cat back, high flow cat, 99+ spec y pipe, power fc. Now I would also recommend upgrading the radiator, ast or cap delete, and intercooler for safety reasons and a bov and boost controller. Get a newer version Power FC because it comes with a base map for bolt ons and you should find 300hp to the wheels no problem on 12-14lbs of boost. There can be many quality parts found in the classified section and depending on what the part is a lot of times it's more worth your money to buy slightly used than brand new.

RobertC

iTrader: (1)

To answer your original question. In my opinion dealing with these cars, eventually you will have the motor out if you have it long enough. That being said, find something that has a good condition exterior and interior, if the motor is in great shape and all of the reliability mods have been done thats a plus. 300hp is a very realistic goal for these cars and you would still be able to keep emissions and all that good stuff.

My personal suggestions would be do all the reliability mods (I.e. Aluminum AST or Delete, Fuel Pulsation Damper, Aluminum Radiator, Intercooler, Efini Y-Pipe, Boost Gauge, Vacuum Hose Job, Fuel pump etc.)

RX7.org has a good write up on the reliability mods. If you wanted to go a step farther and get a PFC (Which you would probably need a stand alone to get to your goal or a flashed ECU) you wont need a boost controller if you want to keep the stock, BNR, or 99+ Spec Twins as the PFC can control the sequential system and give you 2 levels of boost to choose from.

Obviously you will want to go through it and change all the wear items like fuel filter, spark plugs and wires etc.

P.S. Get rid of the accelerated warmup system and the rotary aviation OMP reroute kit is very nice as you will no longer be injecting used engine oil into the car but clean 2 stroke engine oil from an external tank.

Dans93FD

iTrader: (4)

Or you can premix. .5 to 1 oz per gallon of fuel. It will help clean up the fuel system and ensure that the worn out OMP is compensated and the engine has adequate lubrication.

Sgtblue

iTrader: (16)

Agree. Except that packaging is problematic for a somewhat stock car still running twins. And of course, you have to remember to keep it filled.
I don't think two-cycle oil will do anything to "clean up the fuel system", but pre-mixing .5 oz. of oil per gallon is generally accepted as the ratio for a car with a working OMP. I guesstimate.