New Member RX-7 Technical Post your first technical questions here, in an easy flame free environment, before jumping into the main technical sections.

Thinking about buying an RX-7

Thread Tools
 
Search this Thread
 
Old 06-25-17, 07:23 PM
  #1  
Junior Member
Thread Starter
 
billymild's Avatar
 
Join Date: Jun 2017
Location: KC,MO
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Thinking about buying an RX-7

I have never owned a RX-7 or a rotary in any form. The only experience I have with Rotary engines was the old 87 RX7 my brother owned in high school. It was reliable car, but towards the end it would smoke a lot and was hard to start. I have always heard how unreliable the RX7 was, but it all seemed circled around the spinning triangle engine.

The FD RX-7 twin turbo is one of my bucket list cars to drive/own. Never having driven one I'm not sure if I will be a fan or not. I love the way they look and I have heard they handle awesome. 50/50 weight distro and good power makes it sound like a great car for the road and track. The one thing that worries me is reliability of the car, and eletronics.

How reliable are the stock RX-7's? How much ower can be made reliably? Are parts a concern to get anymore?
Old 06-25-17, 07:59 PM
  #2  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Arrow

Buying a Used RX-7

There are some other links in the 3rd Gen. FAQ at the top of this section under 'B' for "Buying". The best one IMO apparently went dead, but all remaining are worth reading. Regardless, the FD was a somewhat finicky high-performance forced-induction sportscar that is now pushing 25 years old in USDM form. IMO you need to have either the skills and ambition to DIY, or relatively deep pockets to buy and maintain one. Otherwise it's a great garage ornament or just a source of frustration and wallet anchor. And this is coming from someone who's been into rotary since 1981 and owned a FD for almost 15 years. I do NOT recommend this car as a DD or a car for someone in school.

Last edited by Sgtblue; 06-25-17 at 08:06 PM.
Old 06-25-17, 08:04 PM
  #3  
Moderator

iTrader: (2)
 
rxtasy3's Avatar
 
Join Date: Jun 2002
Location: Spartanburg, SC
Posts: 9,312
Likes: 0
Received 256 Likes on 237 Posts
dude u don't think, u just buy.
Old 06-26-17, 08:10 AM
  #4  
Junior Member
Thread Starter
 
billymild's Avatar
 
Join Date: Jun 2017
Location: KC,MO
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by rxtasy3
dude u don't think, u just buy.
I did that with my last car. I bought a 1991 Corvette ZR-1. I had never driven a corvette before that in my life. I bought the car sight unseen off of Craigslist and fell in love with the car. It was possibly one of the best fun cars I have ever owned. It had some deferred maintenance at the start, but once that was sorted it was a great touring car. I would drive it for work trips and did a few track days. The last track day is what killed it. Slid off into the concrete wall. RIP

The LT5 is a complex engine with a lot of premitive complex systems. I ended up buying tools to work on it, but I wasn't able to do everything. Honestly it was a great car that I had a ton of fun with, but it didn't need constant tinkering.

The car I owned before that was a 944 Turbo. I have had 944, and 924's in the past so I was very famaliar with the platform. Most people think they are junk because they will blow headgaskets, or timing belts break. This is all from bad tuning or improper maintenance.

Is the RX-7 the same way, or does it constantly need tinkering to keep it running correctly?

People tell me to look for a LSx swapped one. That doesn't really appeal to me since it takes a lot of character from the car.
Old 06-26-17, 09:10 AM
  #5  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Unsupported or poorly done performance modifications, poor maintenance and bad tuning are probably the big three causes of issues...and probably in that order. Obviously if you plan to track a 25 year old car things WILL break and costs rise.

Last edited by Sgtblue; 06-26-17 at 09:13 AM.
Old 06-26-17, 12:24 PM
  #6  
_____________
 
borisf's Avatar
 
Join Date: Sep 2015
Location: TEXAS
Posts: 140
Received 0 Likes on 0 Posts
Originally Posted by billymild
The car I owned before that was a 944 Turbo. I have had 944, and 924's in the past so I was very famaliar with the platform. Most people think they are junk because they will blow headgaskets, or timing belts break. This is all from bad tuning or improper maintenance.

Is the RX-7 the same way, or does it constantly need tinkering to keep it running correctly?

Luckily you don't have to deal with either if you are buying one that has kept the 13b.

Bad tuning and improper maintenance will kill even the most reliable car.

I bought one that was said to work the day before I bought it. Showed up, and it didnt want to start. Still bought it. It did take considerable effort, time and learning to get it to running, but that's all part of the rotary experience.

If you want an LS Swapped RX7, you might as well buy a C5 Vette, as they are cheaper than nicely swapped FD RX7's nowadays.
Old 06-26-17, 12:32 PM
  #7  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Originally Posted by borisf
Luckily you don't have to deal with either if you are buying one that has kept the 13b...
Head gaskets, no. But there are coolant seals. Timing belts, no again. But there are rubber vacuum lines and solenoids.
Old 06-26-17, 04:18 PM
  #8  
Junior Member
 
GregoryRx7's Avatar
 
Join Date: Mar 2017
Location: New Jersey
Posts: 42
Received 0 Likes on 0 Posts
Ima tell you right now bro , compression test before you buy or expect to rebuild an engine then...you need an aftermarket radiator and exhaust system and a front mount intercooler just to keep the car cool , and if you have stock rims then I suggest going wider both front and rear ...this alone will add 5 k at least to the cost of the rx so keep that in mind also i forgot the aftermarket ecu and cost of a tune that should bring it up to around 5 k

Last edited by GregoryRx7; 06-26-17 at 04:42 PM.
Old 06-26-17, 05:59 PM
  #9  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Originally Posted by GregoryRx7
Ima tell you right now bro , compression test before you buy or expect to rebuild an engine then...you need an aftermarket radiator and exhaust system and a front mount intercooler just to keep the car cool , and if you have stock rims then I suggest going wider both front and rear ...this alone will add 5 k at least to the cost of the rx so keep that in mind also i forgot the aftermarket ecu and cost of a tune that should bring it up to around 5 k
'Ima' disagree. A compression check isn't bad advice and an all-metal radiator (usually with larger capacity) is considered a reliability mod. But you absolutely do NOT need a FMIC. It's actually counter-productive to a car running cooler since it's a huge heat-sink in front of that radiator. Cost and looks aside, it requires fabbing, plumbing, relocating things like the battery and usually compromises crash-worthiness. It's also exposed to road debris and slow animals.
Stock wheels are 16 x 8. Stock tire was 225/50 but 245/45's fit just fine, keep the speedometer accurate and don't require fender rolling or silly negative camber.
While a standalone like the PFC is nice, the stock ECU works just fine with modest performance mods like a downpipe, SMIC and intake. You just need to keep to stock boost levels. Many of us ran that way for years w/o issues.

Last edited by Sgtblue; 06-26-17 at 06:02 PM.
Old 06-26-17, 06:25 PM
  #10  
Junior Member
 
GregoryRx7's Avatar
 
Join Date: Mar 2017
Location: New Jersey
Posts: 42
Received 0 Likes on 0 Posts
Aww c'mon who doesn't want to turn the boost up just a little , honestly overhead is nice to have so I would personally enjoy the after market ecu possibly even bigger injectors but that's just me as for tire setup you wouldn't have to roll anything running 265 or 275 in rear with a larger setup in front but hey to each his own
Old 06-26-17, 10:52 PM
  #11  
Junior Member
 
Demarest's Avatar
 
Join Date: Jun 2015
Location: California
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
That's a shame about the ZR1. My buddy had a '91 as well which he ended up in the ditch since someone decided to leave a mattress in the road in the middle of the night. The LT5 was a gnarly sounding machine.

I bought a '91 NA FC a couple years ago and the engine finally had it after a few thousand miles. One of the coolant seals broke in the engine (Similar to what your brother had) after that it smoked a **** ton on start up and it was very difficult to get going.

Do what you can, these are old cars so don't expect to get something that will last you too long. The rotary isn't unreliable (The engine in my NA went 200K before needing a rebuild) but it is a lot more temperamental if you neglect it. Change the oil every 2k miles, think about upgrading your cooling systems, and keep up with other minor maintenance.

If you're going turbo, then don't expect the engine to last as long as the NA, from what people say around the forums ~100k is when the turbo II will need a rebuild. And again, invest in reliability before adding power. But I'm sure you're already familiar with that kind of thing. The FD is a different animal, however, the 13BTT is still a 13B. Pre-mixing is a very popular technique and I even do it myself just to have a warm fuzzy feeling that my engine is staying properly lubricated.

I'd say just research how to care for a rotary and watch a couple buying guides on youtube, they're pretty helpful. Its all about what you want!

P.S. Do NOT switch from conventional oil to synthetic oil in your engine if it has already been running one or the other, this can degrade the coolant seals from what I understand and I believe that's what happened to my NA. (Correct me if I'm wrong anyone, still new.)
Old 06-27-17, 03:38 AM
  #12  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Originally Posted by Demarest
...P.S. Do NOT switch from conventional oil to synthetic oil in your engine if it has already been running one or the other, this can degrade the coolant seals from what I understand and I believe that's what happened to my NA. (Correct me if I'm wrong anyone, still new.)
You're wrong. The type of oil used has absolutely nothing to do with coolant seals.
Old 06-27-17, 07:13 AM
  #13  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Originally Posted by GregoryRx7
Aww c'mon who doesn't want to turn the boost up just a little , honestly overhead is nice to have so I would personally enjoy the after market ecu possibly even bigger injectors but that's just me as for tire setup you wouldn't have to roll anything running 265 or 275 in rear with a larger setup in front but hey to each his own
I've been running essentially stock boost since buying the car. So have many others. The stock ECU already has some "overhead" and kept at stock boost its adequate.Your statement about tires makes no sense. This is a tech section for new members. Opinions are fine if they're essentially helpful to prospective new owners. Your's aren't... imo.

Last edited by Sgtblue; 06-27-17 at 07:37 AM.
Old 06-27-17, 07:18 AM
  #14  
Junior Member
 
Demarest's Avatar
 
Join Date: Jun 2015
Location: California
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Sgtblue
You're wrong. The type of oil used has absolutely nothing to do with coolant seals.
I must have gotten some bad information. Thanks for keeping me honest! Got a lot to learn
Old 06-27-17, 07:34 AM
  #15  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
^I think you just confused coolant seals with oil control rings/seals. Coolant seals are s the rough equivalent of a piston engines head gasket. Oil has nothing directly to do with either one of those. Oil control rings are what the name suggests. Mazda recommended against synthetic because it didn't play well with the latter. Opinions vary among smart people as to the validity of not using today's synthetic. You can search and make up your own mind.

Last edited by Sgtblue; 06-27-17 at 07:40 AM.
Old 06-27-17, 10:55 AM
  #16  
Junior Member
 
GregoryRx7's Avatar
 
Join Date: Mar 2017
Location: New Jersey
Posts: 42
Received 0 Likes on 0 Posts
I mean just in my own experience wider stickier tires help the performance that's all I was saying and compression test wise and radiator wise exhaust wise I think I was spot on so again to each his own
Old 06-27-17, 07:11 PM
  #17  
Junior Member
Thread Starter
 
billymild's Avatar
 
Join Date: Jun 2017
Location: KC,MO
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Good information so far.

My ZR-1 was pretty damn fast with the full exhaust and a tune I had done. It would break 1st and 2nd lose no problem. I had some big ole meats on it too. 315/35r17 in the rear.

If I got an RX-7 it will be an FD for sure. I like the idea of the turbo as I have loved just about any turbo car I have owned. It sounds like you can't tune the stock ECU on these cars? Even on my old 944 Turbo you could tune the chip for more boost. I ran 15 lbs of boost on that with a new FPR and chip to accomadate the fueling.

Sounds like I need to buy a car that has the reliability mods done already. First time I have heard about this, but I have already read some info on all of that. Seems logical.

Can the FD's be bought for $15-18k? Is that a pipedream?

How much does a good engine rebuild cost?
Old 06-27-17, 07:14 PM
  #18  
Junior Member
 
GregoryRx7's Avatar
 
Join Date: Mar 2017
Location: New Jersey
Posts: 42
Received 0 Likes on 0 Posts
Originally Posted by billymild
Good information so far.

My ZR-1 was pretty damn fast with the full exhaust and a tune I had done. It would break 1st and 2nd lose no problem. I had some big ole meats on it too. 315/35r17 in the rear.

If I got an RX-7 it will be an FD for sure. I like the idea of the turbo as I have loved just about any turbo car I have owned. It sounds like you can't tune the stock ECU on these cars? Even on my old 944 Turbo you could tune the chip for more boost. I ran 15 lbs of boost on that with a new FPR and chip to accomadate the fueling.

Sounds like I need to buy a car that has the reliability mods done already. First time I have heard about this, but I have already read some info on all of that. Seems logical.

Can the FD's be bought for $15-18k? Is that a pipedream?

How much does a good engine rebuild cost?
you can def find one in that price range i bought mine for 12k
Old 06-28-17, 03:54 AM
  #19  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
Originally Posted by billymild
...It sounds like you can't tune the stock ECU on these cars? Even on my old 944 Turbo you could tune the chip for more boost.....
Pettit and a few of the other well known rotary builders also provide(d) altered ECUs. PR ECU Upgrade . But for about 50% more, you can get a programmable ECU like the PFC with a commander. Going that route allows you to do things like remove emissions (if you can in your state) without having a CEL. It also typically smooths out transition and all but eliminated the common 3k hesitation on my car. It's what you're comfortable with. If you turn boost up at all you need to consider fuel deliver. Rotaries do not like lean.
Old 06-28-17, 01:11 PM
  #20  
Senior Member

 
littlebit421's Avatar
 
Join Date: Jul 2010
Location: Carolinas
Posts: 467
Received 11 Likes on 11 Posts
Originally Posted by GregoryRx7
I mean just in my own experience wider stickier tires help the performance that's all I was saying and compression test wise and radiator wise exhaust wise I think I was spot on so again to each his own
I agree on the tires, when I use to autocross the first thing you did was buy a good set of tires. When I started I remember saying I need this and I need that, sway bars, suspension, brakes etc. This old timer told me to buy tires first because without sticky tires the rest is useless.
Old 06-29-17, 02:28 PM
  #21  
Junior Member

 
jricci's Avatar
 
Join Date: Oct 2013
Location: Augusta, GA
Posts: 19
Received 0 Likes on 0 Posts
FDs are complicated, highly engineered cars. If you need a part finding one can be a several day/week task and requires a lot of networking. All rubber (belts/hoses/etc.) and fluids need to be fresh. It's not a car, it's a way of life if you treat them the way they have to be treated. Driving them is sort of a happy by-product. I wouldn't let mine go.
Old 06-30-17, 05:31 AM
  #22  
Urban Combat Vet

iTrader: (16)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 12,012
Received 862 Likes on 611 Posts
The FD was in production thru 2002. In addition to MAZDA, there are a multitude of used and new replacement and aftermarket parts suppliers out there. I can go into any local chain parts store and find filters, belts and most other consumables. I've never really had difficulty in sourcing what I needed.
Old 06-30-17, 08:20 AM
  #23  
Banned. I got OWNED!!!
iTrader: (1)
 
Restored Rotary's Avatar
 
Join Date: Jun 2017
Location: Oregon
Posts: 117
Received 8 Likes on 7 Posts
Originally Posted by billymild
I have never owned a RX-7 or a rotary in any form. The only experience I have with Rotary engines was the old 87 RX7 my brother owned in high school. It was reliable car, but towards the end it would smoke a lot and was hard to start. I have always heard how unreliable the RX7 was, but it all seemed circled around the spinning triangle engine.

The FD RX-7 twin turbo is one of my bucket list cars to drive/own. Never having driven one I'm not sure if I will be a fan or not. I love the way they look and I have heard they handle awesome. 50/50 weight distro and good power makes it sound like a great car for the road and track. The one thing that worries me is reliability of the car, and eletronics.

How reliable are the stock RX-7's? How much ower can be made reliably? Are parts a concern to get anymore?
best car you will ever own. Nothing else like it. Give it a month and you will never go back...
Old 07-10-17, 08:43 AM
  #24  
Junior Member
 
alape8's Avatar
 
Join Date: Jun 2017
Location: Colorado
Posts: 8
Likes: 0
Received 1 Like on 1 Post
Originally Posted by GregoryRx7
you can def find one in that price range i bought mine for 12k
That's reassuring as I'm also looking in the same price range. Definitely going to need to travel to get it, kind of tough for a first time buyer like ourselves. Can't wait to get started wrenching though.
Old 07-28-17, 09:47 PM
  #25  
Junior Member
 
ValkyrieJax's Avatar
 
Join Date: Jul 2017
Location: Jacksonville
Posts: 24
Likes: 0
Received 1 Like on 1 Post
Parts will always be an issue, but the Rx7 community is very creative. Go for it!



All times are GMT -5. The time now is 06:56 AM.