Rbrashear68

Hey guys,

I bought my son a 1990 RX-7 last summer and he's been saving up for an engine. We found a rebuilt block that I'm not sure will fit. Here's what the seller claims when I asked if it was from an S4 or S5:

In a real way I've been building Rotary engines for over 27 years i'm 44years old and like tell people, once modified there is no such thing of s4 or s5 the motor has been modified people will tell you that certain things wont match up NOT TRUE i've put an 86 motor into a 91 chassis and if you must know this motor has 1991 rotors, front and rear plates are from a 1988 Intermediate housing (middle) from 1986 and the rotor housings are from 1990 I always mix and match I learn this from different Mazda shops ive worked at from Racing Beat to Mazda Trix to the Dealership to Tri-Point Engineering to having my own shop

Now aside from the obvious risks of buying an engine like this, do you think I'll run into any potential problems. The car I bought my son has the engine still in it, but has a blown seal. So, do you think this should be a pretty easy physical swap-out?

Thanks for any tips guys!

Rick

Icemark

From the description, it should work fine.

The only issue that I can see is what front cover he used, and that could be swapped from your blown motor anyway, and is only important for the MOP.

The only things that really need to match on a motor are the housings and the rotors. Everything else can be pretty much swapped and interchanged as needed.

Rbrashear68

Thank you sir!

My nephew says that there could be a difference on Oil Management systems. He said there is electrical one's and mechanical one's. He said that could be an issue, but he thought we could rob it off of the old motor if needed. Do you agree with this statement?

Thanks again!

Rick

大力士

If he is just selling you a rebuilt block you will have to exchange all the external components over from your old block. such as your OMP, Fuel rails and injectors, upper and lower intake manifolds, Throttle body, clutch flywheel, oil pressure gauge, water pump and housing, alternator, oil fill neck, and on and on. the new block will probably be bare.

Icemark

Yeah that is what the MOP (Metering Oil Pump) is and my reference to the front cover. You will need to use the appropriate front cover for the MOP that you are using.

Rbrashear68

thanks guys!!!

Wow has this really turned into a shady deal! First of all, the guy attempted to charge me tax on the email that was emailed to me. I kept trying to contact them to remove the tax and they sent a reminder for me to pay. I saw a number on the invoice and called it and basically said " as soon as you remove the tax and re-invoice me, I'll pay it".

They finally removed the tax and then I received a message from the seller
You can read my play-by-play here: Rick's Ebay Experience
(Mods, I apologize if the link violates the rules...I'm not intending anything wrong)

I am truly wondering if I am even getting a true street port engine!!!!

Rbrashear68

I have a little peace of mind on this. Since I'm sceptical of this seller, I am having the engine checked and partly disassembled to verify the street port. 501 Automotive out of Longview, TX is going to do this for me once the engine ships to me.

trochoid

iTrader: (6)

No need to take anything more than the intake and exhaust manifolds off of the engine to check for porting. If the comp test is done with a true rotary compression tester and the engine comes as a bare block, labor should be no more than 100-125. It will need a flywheel, clutch, tranny and starter installed for the comp test.

As far as the swap, that's pretty straight forward. Take pics before and during removing the old engine. As you remove parts form the old, install them on the new. Makes keeping track of parts, nuts/bolts, peripherals easier. The link provided is for the online FSMs.

http://www.wankel.net/~krwright/cars/rx7/manuals.html

Btw, what did you pay for the engine?

Rbrashear68

Thanks bro! Click on that link in post #7 and you'll be able to read my whole diary of what I've dealt with including the selling price, etc. It has gotten a little messy imo, but I'm attempting to keep it minimal.

Rbrashear68

Whoops I mean the link in Post #6.