doylie24

I have a few questions about an RX-7 and maybe putting a ls1 in it. There is a 1995 RX-7 for sale here. Twin turbo, 5-speed with new clutch and flywheel. New radiator. Body has a few dings but nothing you can see unless you get really really close. Has 55k on the clock. Now the major problem is the engine has no compression. He said possibly head gasket, but I am not for sure cause I have not seen it in person yet. But he is only asking 4,500 for the car. I think it is a steal. My question is what could be causing no compression? I know this is ls tech forum, but I did not know where else to ask aside from calling and talking to someone who has experience with these engines. I am thinking about if I do buy it to put an ls1 in it. Don't be rude or anything, if you don't know the answer or have some advice please don't post.

Starz T/A 17

iTrader: (6)

First of all I don't think that rotary engines have head gaskets. It could possible be a seal or something but not really familiar with rotary engines. Honestly you might get lucky on here and find someone that has rotary experience. But I would recommend joining a RX7 or RX8 fourm to get some more information about what is common issues with the cars. If it was a more normal engine we could suggest things, but those rotaries are night and day from a standard combustion engine

doylie24

Thank you for your advice, do you happen to know anything about putting an ls1 in these cars? I will look into those forums.

Starz T/A 17

iTrader: (6)

I would check out the hybrids and conversion section in this fourm, its specifically for discussion on swapping LSx's in non LSx cars. A lot of guys on here have done that swap so theres plenty of good information there!

mikezohsix

try "no rotors.com" or something like that for putting non-rotary engines in Mazdas. The guys there can help you decide what's going on with your current motor, and certainly help with what fits and what doesn't in the RX7.

There's actually a lot of good information there that I've used for my LS1 Volvo. Others that are reading this might want to check it out too.

zipster

iTrader: (5)

The engine sounds like it has a bad apex seal. Basically its blown. I would buy the car, sell the twin turbo, trans and everything related to the 13b, then put in a LSx, that car has fantastic brakes and suspension. The ls motor makes it an awesome reliable car. Don't get me wrong, the 13b is great, but are very temperamental.

I have always loves those cars, I built my friends car, he ended up with 512rwhp, ran high 10s at 135mph on street tires, the thing was wicked fast........ when it ran.

go get it.

lsvega-s

I have built several rotaries in the past. I can honestly tell you it is not a head gasket, because they don't have them. It could be the Apex seal and if it is then the engine is shot. These cars were also notorious for washing the oil off of the seals so before you junk the engine try this.
Pull the plugs and put some Marvel Mystery oil in the plug holes.
Rotate and get each side of the rotors.
Then put the plugs back in and pull the fuel pump relay.
Crank the engine. If the seals were just stuck it will free them and you will start to here the compression start to come back.
If this happens then replace the relay and give it a shot.
At least if it works you could sell the engine running when you do your swap.
Hope this helps a little.
Definitely do the LSX swap if the funds permit. It will be an awesome car when you get it going.

doylie24

Thanks for the info guys. How much could I get out of selling the turbos and transmission? Also how much for the engine if I can get it running again?

Pocket

iTrader: (22)

Good info. If you want more info on the matter, look into RX8's as they are notorious for washing the apex seals down and there are dozens of fix-its for that. What worked best for my sister's RX8 was a squirt of trans fluid in the plug holes (fun to get to)

If the seller isnt a complete dimwit, you probably are looking at bad seals

Nate_67RS

NO the RX7 does not have a head gasket and that person should be shot for saying that was the issue..... if you have no compression on a rotary you chuncked an apex seal (rx7 owner and member of a few forums)

Nate_67RS

saved 3 cars this way. one literally was sold to a junk yard in my area because of this i got the car for 200 sold it for 900 after refreshing it.

doylie24

How much could I possible get out of the turbos, transmission, and engine(depending if I can get it running)?

Nate_67RS

depending on what work you do to the motor (we are talking a 13b turbo motor) 250 maybe 300 on stock setup but 300 would really be pushing a motor in need of a rebuild. but rebuild the motor do a street or bridge port go with s5 rotors and 3mm apex seals and the stock turbo can push 350. update the turbo get a megasqurt system larger injectors and 400 with tunning is within range maybe more.

but to get past 400 is going to cost alot more than dropping an LS1 into it with a base line of 350 and adding a mild cam maybe some boost for about what you would pay to make 350 hp in a 13b you could almost double the hp and triple the tq with an LS1. But i love the rotary and it's high rev limit but if you and a drag car the cheaper route to the same power is an LS1 if you plan auto crossing or staying at high rpms the rotary will be a a fun engine.

doylie24

Can anybody tell me if I could do this swap for 5k?

lsvega-s

If your 5k includes the price of the car then no.

If not, then I guess it would depend on what you have to give for the engine and trans. If you get yourself a good deal and can do the work yourself then you could probably do it for that, and what you get out of the RX7 parts.

I have been away from the RX7's for a while and don't know how much these engines and parts are selling for anymore but the TT's used to bring good money if they were running. Not too much if they are blown, they tear up too much when they pop a seal.
Good luck

doylie24

How hard is it to do the swap your self? I have found a ls1, t56 combo for 2,000. And I found the subframe, dirveshaft, torque arm, trans crossmember and all mounting hardware for another 2,000.

doylie24

Anybody know of any shops around the Kansas City area that could do this swap or help me in this swap?