ive got a 1988 mazda rx7 convertible, similar to this, but in white. with the original 13b rotary. well teh water seals have died, necessitating a teardown and rebuild. also needing injectors so im looking at around 1200 to bring the engine up to 100% Soooo im contemplating an engine swap, im htinkin 305 v8, or a 4.3 v6 ( carbed), what would yall do, rebuilding engine ( rotary is not an option. too costly at this point), someone recommend a good swap candidate? ( engine/trans )

Rebuilding the rotary is too costly but you're willing to spend the cash to do a V8 swap?  that's great.

You can rebuild the rotary for under $500 with decent parts.  I've done both several times and I can tell you that unless you're going with crap motors and parts, you're not going to do a swap for anything less than $4000 and that is with YOU doing all the labor...pulling the old motor and tranny, pulling the donor motor and tranny, figuring out the drive shaft and rear end, fabricating your own motor mounts, fabricating your own wiring, et cetera and so on.  Even doing a 7m-GTE swap using junkyard parts still cost us $1800 and we were lucky for having been able to un-seize a block that was tought to be bad, and thus was had cheap.  Doing a swap using a real motor along the lines of an LS1 would send you in the $7000+ area.

The only engines I would ever consider candidates for swapping into MY car would a 20B, peripheral port 12A (my favorite), 13BREW, 1jz-GTE, SR20DETT, or a VG30DETT.  US V8's and V6's would be out...their heavy, wide, and long stroke motors aren't really suitable for the application.  I would consider an LS1....LS1 is the perfect engine for everything.

Hit up rx7club.com and sift through their engine swaps.  There's guys on there who've built peripheral port 12A's for $500 and under and are putting down 250+ rwhp all motor...and sound sick doing it.

Just looked it up and the pineapple racing water seal kit is $185.  If all that's wrong are water seals are blown out that that's all it cost to rebuild the engine.  Tearing the engine down is kiddy stuff, especially if you have something like a haynes manual...I did my first with no manual, I just put everything back together the way it came apart.

Now, I can't tell you what to do with your car...and I'm not trying to come off as sounding that way...I'm just trying to point out that, in no way, is swapping a foreign motor into the chassis easier or cheaper than rebuilding a 13B and I don't want you to kid yourself about it.  There's been a million people out there who thought they'd do it because they figured it would be easy and cheap and now half finished projects hold their back yards down or they bought cheap engines and ended up in the same situation they were in before...a car with engine problems that's not saving them any money.

The only correct reason to do an engine swap is cool factor and you got to pay for it...and you might as well pay for it and do it right.  Do something impressive.  Spending the kind of cash it's going to take to put a reliable 4.3l GM engine is going to leave you with a 150lb heavier lump in the front that's only making 30 more horsepower at the crank...and rolling through a slushbox you're going to lose any gain you had there.

Quote from: makenzie71 on October 05, 2008, 08:04:14 AM
Rebuilding the rotary is too costly but you're willing to spend the cash to do a V8 swap?  that's great.

You can rebuild the rotary for under $500 with decent parts.  I've done both several times and I can tell you that unless you're going with crap motors and parts, you're not going to do a swap for anything less than $4000 and that is with YOU doing all the labor...pulling the old motor and tranny, pulling the donor motor and tranny, figuring out the drive shaft and rear end, fabricating your own motor mounts, fabricating your own wiring, et cetera and so on.  Even doing a 7m-GTE swap using junkyard parts still cost us $1800 and we were lucky for having been able to un-seize a block that was tought to be bad, and thus was had cheap.  Doing a swap using a real motor along the lines of an LS1 would send you in the $7000+ area.

The only engines I would ever consider candidates for swapping into MY car would a 20B, peripheral port 12A (my favorite), 13BREW, 1jz-GTE, SR20DETT, or a VG30DETT.  US V8's and V6's would be out...their heavy, wide, and long stroke motors aren't really suitable for the application.  I would consider an LS1....LS1 is the perfect engine for everything.

Hit up rx7club.com and sift through their engine swaps.  There's guys on there who've built peripheral port 12A's for $500 and under and are putting down 250+ rwhp all motor...and sound sick doing it.

engine with 45k miles ( 305v8) and trans 350,  exhaust  included. ( WITH WARRANTY) injectors for said rotary, 93 a piece times 4, seal kit 220 plus shipping, apex seals, 53 each times six so if they did it for less than 500 they are using used parts, if not where did they get them cheap?!?

Send your injectors out to be serviced...pretty much any diesel shop will be setup to do it and if not there's half a million shops you can send them to online.  Going rate is about $25 per injector plus shipping.

You didn't say the apex seals were bad.  Apex seals don't need to be replaced if they're not bad.  You said a water seal was blown.  Tremendous difference and, if you'll look at my second post, you'll find that the pineapple racing water seals are $185 plus shipping.

rotaryaviation sells apex seal kits for $226 shipped.  rhdjapan is $250 + shipping.

And I wouldn't trust a business that'd try and unload a 20 year old engine and tranny on me for $350...and, again, even if you could snag the motor and tranny so cheap, why go through such strenuous effort for such a lackluster drivetrain?  You really do need to step back and look at this project as a whole.  Don't just stop at what motor you're going to put in it.  The motor may be the heart of the matter but I'm willing to bet you've never seen a heart flopping along down the street minding it's own business.  If you're going to do something, do something big.

im not trying to get a high HP beast, im using stock rear end, i have access to welders and shop space, ( almost 6k square feet) so fab wont be an issue neither will wiring. ive wired things up far more complex then an rx was in its wet dreams

Quote from: makenzie71 on October 05, 2008, 07:17:45 PM
Send your injectors out to be serviced...pretty much any diesel shop will be setup to do it and if not there's half a million shops you can send them to online.  Going rate is about $25 per injector plus shipping.

You didn't say the apex seals were bad.  Apex seals don't need to be replaced if they're not bad.  You said a water seal was blown.  Tremendous difference and, if you'll look at my second post, you'll find that the pineapple racing water seals are $185 plus shipping.

rotaryaviation sells apex seal kits for $226 shipped.  rhdjapan is $250 + shipping.

And I wouldn't trust a business that'd try and unload a 20 year old engine and tranny on me for $350...and, again, even if you could snag the motor and tranny so cheap, why go through such strenuous effort for such a lackluster drivetrain?  You really do need to step back and look at this project as a whole.  Don't just stop at what motor you're going to put in it.  The motor may be the heart of the matter but I'm willing to bet you've never seen a heart flopping along down the street minding it's own business.  If you're going to do something, do something big.

its the local pull-a-part  i wont use "rebuilt injectors. ive no fire insurance on my car 

Well throw a budget out there...you can do so much better than the 305.  You may think now "I don't want a high power beast" but you know you really do.  Plus, with the 305 what you're going to get is a low power gas guzzling slushbox that weighs 250lbs more.  Even going with american engines you can do better than the 305...

yeah i know. im trying to keep budget under 1k which can be done. this can be done with either of the two afore mentioned engines,  or a 350, engines are all aorund the same price. only concern is the oil pan/sump, will have to modify that. ( NP been there done that) but i look at it this way, im starting with a lo-po engine, which can be built up, either 305 or 350 or hell the 4.3 can do this. but not goin high power until i upgrade rear end. ( which is in the works) and trannies, im still torn, id rather have a manual, rather than an auto any day 

That's one of the biggest reasons to stick with Japanese engines.  We've crammed 7m-GTE's, 1jz-GTE's and even a 2jz-GTE into FB and FC chassis' and they all needed minimal modification to handle the 5spd trannies made for the engines.  Hell, the 7m was so easy that even wiring it all you had to do was cut the connectors from the dash/body harnesses off the RX and match the wires to the corresponding pin on the 7m ECU.

I've seen one GM swap RX with a decent manual tranny...LS1/T56 combo...and it wasn't cheap.  However, SR20's and 5spds are a dime a dozen...but no matter what you do converting a vert to a 5spd is a chore all it's own using factory parts.  If nothing else you can always just buy another RX longblock.  You can get good engines for a LOT less than $1000...you could even do a turbo swap on that budget.

I wouldn't worry about the factory rear end until you're getting in the 300whp area.

i had a 1980 chevy luv i wanted to stuff a 327 into. but circumstances prevented the venture and i sold the truck to a crusher for 50 bucks. (on the plus side i got really, really hammered that weekend. ) 

ive no idea what 7m-GTE's, 1jz-GTE's and even a 2jz-GTE crap means, i speak english err, say x engine out of x car, but using late model engines, and transmissions, ive also got to swap computers, and wiring. whereas, a carbed engine isdone with minimal fuss 

to quote special T....  "google is your friend"   

naah i dont watch too fast to furious, too many times, i jsut say what it is. if i have to google a reply to comprehend it, i dont pay much attention to it

Supra engines and Nissan 240 engines.

Carb'ed engines leave you a lot more to do than just stab the motor in, especially if you want to have a functional dash.  This is what I'm mean...don't over simplify it.

LS-1   lol
I know they make kits for the rx-7 applications.  A distant friend of mine swapped one a couple of years back.  It was indeed very sick.  In a very good way.

is this just for the sake of an engine swap ?

i'd personally just rebuild the stock spinner, and enjoy -not- having to fix piddly crap every week, or rigging things to work. there always seems to be something that isn't quite right with a non-stock swap.

of course there is a fun side to having a 327 in a chevy luv though (been there, done that years ago) but with gas prices of today, no thank you.

good luck with the toy !

Quote from: makenzie71 on October 06, 2008, 03:12:12 AM
Supra engines and Nissan 240 engines.

Carb'ed engines leave you a lot more to do than just stab the motor in, especially if you want to have a functional dash.  This is what I'm mean...don't over simplify it.

Or theres figuring out how to get computer from car a to work in rx7, and engine from car a. with transmission. Nooo thank you. not needed. thsi crap i can do myself. get a gauge kit, wire it in, along wiht tach, oil temp, water and fuel
the supra engiens 1 are hard tofind around here, and when found, are eitehr riced err ragged out, or expensive. hell ive found ls1's WIHT transmissions, sub 2k. i guess its all in the location of teh donor part. ( like where its from and such)

Read the posts...wiring the dash off the 7m ECU was just a matter of matching signals.  It was easy.  Speedo was even compatible.  You're not going to find that with a US engine.  I'm offering advice as someone whose been there and done that...11 conversions under my belt, I may be worth listening to.

You'd have to hunt an engine.  You can buy full clips from Jarco for under $2k delivered to your door and have EVERYTHING.  Rabidchimp sells fresh 7m blocks with metal gaskets for under $1500 shipped and you can get an R154 from a supraforums member for under $250, and all the wiring and supporting nonsense for another $250.  That's some barebones stuff, though.  This isn't the only route, though.

Lets look back at your idea and say you go for that $350 305ci and slushbox.  What are you left with in the end?

an engine and transmission . which runs