RX-7 ......What do i do with it now?! Swap? fix?

"SantaRita" (SantaRita)
07/23/2014 at 17:20 • Filed to: None

Just traded a macbook for a half-running 1990 rx7. NA motor making 160 hp or so and spewing coolant.

yes i do know better,and no you wouldn't have been able to stop me...

i'm even selling my 2007 VFR800 to make the jump back to cars and fund an engine rebuild/swap if i need it. estimate $4000+ for that as my complete budget. i'd like to refresh the suspension in that budget too.

but what do i do now? it's a water seal failure i think...cheap rebuild is 20 hrs and 300$(just water seals)-$500(with new apex seals) while comprehensive rebuild is closer to 1200 for all the gaskets....with options in between and the possibility of needing a rotor/housing.

lets call rebuild the 30hr 300-1200$ option that i t probably would be.

used motor swap option is also close to $1200-2000 but i could put in a turbo engine and trans if originality isnt big deal and more power is nice. this motor would be unknown and untested.

big swap option means something like an LS1, although i favor something weird like a Saab B234R, the ls1 is plentiful and the swap is documented. This is easily a 2000$ option and loses more of the originality but gains reliability and power.

right?
so oppo...what option isright for this S5 Vert?

DISCUSSION (32)

Henry Diesel > SantaRita
07/23/2014 at 17:21

sit back and gloat because you have an rx7

Kit 'Haddy' Iwamatsu > SantaRita
07/23/2014 at 17:22

4.3L GM V6, with a turbo. Swaps in like an LS, same mounts and everything.

RotaryLover > SantaRita
07/23/2014 at 17:23

Swap for 13BT!

Will with a W8 races an E30 > SantaRita
07/23/2014 at 17:27

Where is the water leaking?

I would call $1200 very optimistic for a rebuild - all the hard parts have to be in good shape, which is unlikely unless the motor is lower mileage.

Used motor swap is much cheaper and easier. Plan on $500 to get a motor, swap it in a weekend. This is the route I took when the apex seals shot out the tailpipe on my '86. S4 or S5 motor will work, assuming you premix. You will be premixing, right?

Turbo swap is mostly out of the question. Much easier to just buy a turbo car.

LS swap, as you said, is mostly cheap and easy.

Or, if you really like, you can come up to Michigan and buy my '86 instead. Already has all the suspension goodies and a header and probably a blown side housing seal :)

DatASSun > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:27

so why not a v8 ?

Mr. Ontop, No Strokes, No Smokes...Goes Fast. > SantaRita
07/23/2014 at 17:28

I approve. However if you are in California, that GM engine swap might cause problems when you go to get it smogged. Maybe swapped out for the Turbo Mazda will be the way to go. be aware though, that these cars are a little thirsty.

Kinja'd!!!

Will with a W8 races an E30 > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:29

There's a chumpcar team running an FC with a GM 3800. Little quicker than stock, and dead reliable. Better fuel economy too.

DatASSun > SantaRita
07/23/2014 at 17:32

Just got done with my 5.3 liter swap and T56 6 speed trans. Well not done but the car starts runs fine and moves just need a stupid drain plug for my radiator before cruising.

now that I look back I was in the same position you were wondering do I go SR20 , RB , 1JZ ? Then realized I'm not made of money and when the option that's the most reliable makes the most power it's the obvious best option. Now that being said I sacrificed the what I call " damn that's different" Factor but gained more power than I would with any other swap and more reliability than all of them. And since the swaps been done in the past you can look it up as you go online for help.. If you go the "Damn that's Different" Route you'll be paying for it .

Kit 'Haddy' Iwamatsu > DatASSun
07/23/2014 at 17:38

Lighter, weight sits further back., can rev quicker if built right, better fuel economy.

Kit 'Haddy' Iwamatsu > Mr. Ontop, No Strokes, No Smokes...Goes Fast.
07/23/2014 at 17:41

You should pass the ref on the first try if the motor came from a newer vehicle and still has its emissions tech in a stock config.

Jordan and the Slowrunner, Boomer Intensifies > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:44

Is the pre-Ecotec 4.3 lighter than the LS? Since it's iron, I figured it would be heavier.

Nick, Drives a Cobalt LT > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:48

That isn't always true, I heard a night mare about the cat beign placed an inch too far back and the inspector failed him.

Wouldn't even take a bribe of a couple hundred dollars....

Kit 'Haddy' Iwamatsu > Jordan and the Slowrunner, Boomer Intensifies
07/23/2014 at 17:49

about 415 dressed on v6 vs about 500 dressed v8. Not much of a difference really.

Jordan and the Slowrunner, Boomer Intensifies > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:52

A iron block LQ4 only weighs 525. An LS1 weighs around 425. Only thing a 4.3 would be good for is budget, and that is a maybe.

Kit 'Haddy' Iwamatsu > Nick, Drives a Cobalt LT
07/23/2014 at 17:53

Depends on the individual ref, but, technically, moving the cat does change the emissions config. Temperatures are vital to cat operation, and placement is critical. I doubt that was the only reason though.

Nick, Drives a Cobalt LT > Kit 'Haddy' Iwamatsu
07/23/2014 at 17:56

It was the only reason, it was a V8 swapped 240sx, everythign else was in proper operating order, and the only thing on the fail sheet was cat placement.

Kit 'Haddy' Iwamatsu > Jordan and the Slowrunner, Boomer Intensifies
07/23/2014 at 18:01

I have an LS1 sitting in a crate in my garage. 425 might be nekkid. With flywheel and accessories it was waybilled at 515. Subtract the 20 pound crate, and its 495.

And, lets face it, 4.3L v6s can be found almost everywhere for a song. LS1 engines... not quite so common.

I'm not seriously advocating one way or the other, and was trhowing an option out there I have personal experience with. I have done a few insane engine swaps, and a few sane ones. I've put 6bt's and 4bt's into for E-series vans, 4.3L v6s into jeeps, blown 460 ford big block into mustang, LS1 into a series 80 scout, and SBCs into FJs. One thing I found, in the end, is the more common the engine, and the cheaper, the better it generally is once the 'wow' factor wears off. Especially if you want to commute it.

DoYouEvenShift > Jordan and the Slowrunner, Boomer Intensifies
07/23/2014 at 18:02

I think they are within a few pounds of each other depending on configuration. Iron block, iron head 4.3 is low 400s. All aluminum LS, and composite intake ia hihj 300s low 400s.

Kit 'Haddy' Iwamatsu > Nick, Drives a Cobalt LT
07/23/2014 at 18:03

Strange the ref would bother to research such a tiny thing, especially since it would be hard to measure to such precision (inside bends, out side bends, down the middle of the pipe? I wonder what the OEM spec is...)

Either way, Cali isnt car modification friendly, honestly :<

Jordan and the Slowrunner, Boomer Intensifies > Kit 'Haddy' Iwamatsu
07/23/2014 at 18:07

The thing with the LSx motors is they are more common now than the 4.3. That is why they are so used. You can find them anywhere from a Camaro to a box truck. If you want a light weight N/A motor, the LS1/2/3/6/7 are great. If you want an engine that can hold shittons of boost, go find a wrecked Silverado or Surburban with an iron block LSx. There really isn't a reason to swap a 4.3 anymore other than the length of the block.

Kit 'Haddy' Iwamatsu > Jordan and the Slowrunner, Boomer Intensifies
07/23/2014 at 18:14

Or find an L33/LM4 and get aluminum block for truck block prices. Under 1k at my local yard for one with a 12/12000 warranty. I ahve found LM4s for sale for under 500.

Nick, Drives a Cobalt LT > Kit 'Haddy' Iwamatsu
07/23/2014 at 18:20

Well the engine was not out of any other car it was a crate engine, and i can't rmemeber if he said how he measured, but I think the distance was after the collector, I could be wrong, and it was a straight shot from collector to cat. Cali isn't mod friendly, NH sure as hell is though.... haha

roflcopter > Will with a W8 races an E30
07/23/2014 at 18:26

I second basically everything he said, and I'll add a little more.

I just did a turboII swap on a buddy's FC and while it's not the biggest deal in the world you better be prepared to do some home cooked wiring, ECU stuff, mounting(especially if you go FMIC like he did), and lots of other little stuff that isn't a direct swap. On a rebuild... you will NEVER rebuild a motor with just coolant seals. If the coolant seals are blown, then there's been heat issues and something else will be out of spec as well.

If you do decide to do a rebuild, let me know because I have all of the specs listed out and a spreadsheet to plug your numbers into, makes life a lot easier. And I don't know how much engine building you have done but they are a different beast and if you go by the 'looks good' approach you will run into tons of issues. Measure EVERYTHING. Some specs are less than .002" and need to stay that way.

Anyways, consider me jealous, an FC has been on my list for quite a while and you got a good deal it would seem.

Kit 'Haddy' Iwamatsu > Nick, Drives a Cobalt LT
07/23/2014 at 18:30

I live in TN, and dropped a cummins 4bt diesel engine from a heavy duty bread truck into my E-series ford van, along with an NP435E and Dana 18 tcase. No questions were asked when I rolled into Memphis emissions inspection. They just heard it was a diesel, checked the lights and brakes, then pushed me out of the way.

Nick, Drives a Cobalt LT > Kit 'Haddy' Iwamatsu
07/23/2014 at 18:41

Same thing here too haha

95 and older needs NO emissions inspection.

96 + gets plugged in except diesels and they don't care how modded you are, so long as the car has brakes, and seems safe.

HideyoshiJP > SantaRita
07/23/2014 at 19:46

Oh, nice. S5. What version? I've got a neglected '89 GXL I shunned after a hail storm that I swear I'll get the body fixed on one day. Enjoy, and make sure you stockpile door handles and interior parts.

DatASSun > SantaRita
07/24/2014 at 09:17

Best Bet hands down is the LM4 5.3 but it's all aluminum just like the LS1 . I just completed mine should make 350 to the ground all day long . The best part it fires right up every time . Over and Over and Over and Over and Over and Over...

SantaRita > Mr. Ontop, No Strokes, No Smokes...Goes Fast.
07/24/2014 at 09:23

non smog state!

SantaRita > Kit 'Haddy' Iwamatsu
07/24/2014 at 09:27

any cars running this motor? i'll be short on headroom so i'll have to have lower intake heights, etc. when i've looked at the Ls motors the truck variants are too tall...

SantaRita > HideyoshiJP
07/24/2014 at 09:29

It's a triple black vert...i'll add a pic or two up top

Mr. Ontop, No Strokes, No Smokes...Goes Fast. > SantaRita
07/24/2014 at 11:39

That being the case........

Kinja'd!!!

Kit 'Haddy' Iwamatsu > SantaRita
07/24/2014 at 12:39

http://www.norotors.com/index.php?topi…

It's been done before, apparently.