valley

iTrader: (1)

Yes it is, and you can save ~200lbs by doing to the car what you would have done during the swap. Also, the (again, fully dressed) LS1 was listed by GM as being 500lbs, when they still sold the crate motor, for the manual. The auto was listed as being notably lighter because of the flex plate vs. flywheel.

Furthermore, "nearly 50/50" isn't 50/50, and as you said yourself, the handling difference was noticeable and I doubt you're a professional. That it decentralizes, raises, and pushes a good bit of the weight further out is also less than ideal regardless of how minimal people with the swap may consider it.

As to modified component weight; that's why I said, again, [smart] people go by component weight. I don't want to **** up eage8's thread but the old wheeze about "it's only 50lbs or so" is a lie.

LargeOrangeFont

iTrader: (7)

Excellent misinformation. No Aluminium LS crate engine is 500 lbs fully dressed. Enjoy your current rotary, and the one after that.

I'm done hijacking this thread.

valley

iTrader: (1)

GM, the makers and sellers of the motor disagree with you. My own ls1 swap is nearly finished, in hindsight, I should have kept the rotary.

LargeOrangeFont

iTrader: (7)

Are you talking the old style LS crate motors with EVERYTHING on them? - PS, alternator, manifolds, flywheel and clutch? If so, yes those were approaching 500 lbs. They don't sell them like that anymore unless you get a E-Rod kit and that has a bunch of emissions related stuff with it.

People don't typically use E-Rods for RX7 swaps, they use the complete crate engine only. No accessory drive and no flywheel or flex plate. That is what I was referring to.

Why do you regret the V8? You'd be one of the first people I have heard of that does.

clokker

iTrader: (2)

Why is that?

BLUE TII

iTrader: (9)

Enjoy your current rotary, and the one after that.
and the one after that.
and the one after that.

This.
I want an LS Mazda so I have something fun to race when I am rebuilding my rotary (which I also find enjoyable).

The LS2 is 400hp out of 6 liters, its going to be more reliable than 400hp out of 1.3 liters.

rx7 SE

iTrader: (5)

You'd be surprised, I know of several on the forums who are unhappy with their v8 swaps and are going back. When its all said and done, reliability is the only advantage that expensive and time consuming swap will get you. The turbos these days (and near future) will make plenty of useable torque in a rotary with a longer power band. But everyone knows this by now .

clokker

iTrader: (2)

I disagree.
Along with "reliability" (which is no small thing to ask for) one also gets a multitude more options, both in parts and service. You can have a piston engine rebuilt in any small town garage and buy parts for it in every box store in America.

Fuel consumption is less in a piston engine when compared to a comparable horsepower rotary.

I'm a longtime norotors member and I'd say a large percentage of the build projects featured there fail (or just peter out) because of issues not related to the drivetrain at all...rust, bad bodywork, electrics, suspension, etc. Basically, the same problems that would exist if the engine hadn't been swapped.

LargeOrangeFont

iTrader: (7)

I'd love to see the swaps of the guys that want to go back, and if they were finished or not.

I agree about the V8 swap being for reliability to a point. In a track car up to around 400 WHP, yes you can build a rotary to do the same thing as a V8, but it has to be built right. The V8 will obviously be simpler, more reliable and run cooler. It will also run on 91 fuel. Beyond that power level in a track car there is simply no room for error, and that is where a V8 will make life easier long term.

For a street car the V8 makes the car more driveable at any power level because of the wider powerband. Some like the lag and boost, but that is personal preference I guess. The V8 lets you tip in the gas in any gear and go.

Craze8

I swapped an FD for a friend, you would need to add him to the list of unhappily swapped rx7s. The ls is nice, dont get me wrong, but with as much as he spent getting a good ls with a t56, harness and all the other goodies to go along with it all he just wasnt happy with it when it was done. Alot of work goes into the swap, as well as money and time. Especially if you do it right the first time with cam and headers etc.

LargeOrangeFont

iTrader: (7)

What is he not happy with? The power? The sound? The cost?

BLUE TII

iTrader: (9)

Especially if you do it right the first time with cam and headers etc.

See, I'm far from convinced that is the right way to swap.

By the time you cam up an LS to 500rhwp+ and build the valvetrain to rev you end up with a race engine that has all the fuel economy and driveability issues of the rotary you just took out.

I think it is better to run the LS in near factory trim (intake/exhaust/reliability mods) where it retains all the advantages of reliability as well as driveability and fuel economy over the rotary.

If you want the most power- go with an LS7 to start with and be happy with "only" 400-500rwhp.

*my rotary actually dynoed slightly higher than one of the two C6 Z06 Corvettes that have been on my local shops dyno.*

That Z06 has been raced the last 4 years on the original engine and the other had a fresh engine under warranty as it was also raced the last 4 years.

Not a dig on LS7 reliability- I am lucky to get a year of racing out of a turbo rotary.

BTW eage8, just tell us when and I for one will shut the hell up and stop jacking your thread in an alternate direction.

LargeOrangeFont

iTrader: (7)

An LS3 can make 500 WHP and be pretty tame on the street with just a cam. It will get low 20s MPG on the highway and run 91 octane fuel. It won't pass smog, but it is very drivable on the street or track. The only internal mods that need to be done to the engine are valve springs, pushrods, trunion upgrade, and if you are gonna track it often, rod bolts. You'd want a few more items for a "track only" engine, but those don't change drivability. Bottom line - You don't need any exotic parts to make 475-500 WHP and it will live on the track for a long time.

But yes you want headers and a good exhaust like you would put on any car you are trying to make power with.

You do not need an LS7 to track the car.

GMPP makes a 525 HP LS3. It is just an ASA cam (same cam I run in my car) in an otherwise stock LS3.

I have an LS1 (5.7) and for me to make 500 WHP, yes I would need some expensive parts, stroker kit, new intake. I could get to 450 WHP with a ported set of cylinder heads.

j9fd3s

iTrader: (3)

my friend put an LS? into his 9 series volvo, and its the perfect match for the engine, for a bunch of reasons.

its the easiest engine swap in the world, if you put the T56 shifter in the Volvo shifter hole, the stock GM engine mounts are sitting on the volvo cross member. the car and the V8 use the same PS pump, so that works. the Volvo uses a bigger radiator, and its radiator hoses just happen to fit the V8 like its made for it. the volvo tach uses the same input as the GM ecu outputs, so that plugs in.

the GM exhaust basically puts its flange where the volvo system has its flange, so you could run a stock exhaust with cats and o2 sensors.

the 90's volvo is OBD2, so its already got the hardware for all the emissions stuff on the gas tank.

basically the only tricky part was the steering column needed the right manifold to clear, and the GM clutch switch is backwards from every other car in the world, and it does something weird if its not there, like not turn on the cooling system or something.

power is up by 50%, ~200hp to "350" hp, both flywheel. mileage is up as well, 12mpg to like 14mpg, he's got a heavy right foot.

so its all win.

why is it perfect for the wagon? well aside from being the easiest swap in the world, it even looks stock, the power delivery of the engine is about what you want for the wagon.

the engine feels really flat over 2500rpm, so its boring, it sounds like ***, and the trans sucks, it doesn't feel like the lever is actually connected to anything, its fast, but on the street its really not much fun

the only other real con to the LS is that normal parts can be crazy money, like $300 water pumps.

rx7 SE

iTrader: (5)

Fritz gets about 7k track miles on his motors which usually is around 3 years. You should talk to him as his setup is usually bullet proof other than warping manifolds and turbos giving up.

valley

iTrader: (1)

That is what "fully dressed" means. Accessories, as a vague rule of thumb tend to weigh in the same ballpark as each other, so starting with fully dressed weight and going down makes a bit more sense, to me, than going short block and up, especially with n/a vs. turbo.

I received my tii as a roller. Even taking great pains to price out my swap and doing most of the work myself, including things like motor mounts, and some custom work that had to be done for the way I'm fitting the motor, I'm still over budget. Putting a 13bt back in instead would have got the car back on the road over a year ago. Also, it would not have bumped me up a great many classes in most leagues simply because the motor isn't original to the chassis (something I didn't look into quite as much as I should have).

Furthermore, half a year or so after I started I found out what a number of the high hp rotary guys are doing to keep their motors more reliable at higher numbers: water and/or meth injection. I also starting finding out about LSx issues when they're tracked hard. Given my goal is only ~400-425whp, it will end up adding ~150lbs (vs. similar mods/hp with a rotary), costing more in both time and money, for something that probably won't be as reliable as a properly setup rotary (even when it's properly setup). All of this along with a bunch of other small things like insurance, part cost, if the car is wrecked I won't want to build it again, etc. have turned what was to be a unique (if relatively cheap) LSx swap into a headache that in hindsight was totally unnecessary.

I'm sure it'll be be a very fun, enjoyable, and eventually competitive (once I get a nice suspension and seat time in it) car, when it's done, but it doesn't change these facts.

Sorry for the highjack eage8.

LargeOrangeFont

iTrader: (7)

They are not even that much from the dealer.

You can get a water pump for an LS engine for well under $100, check Rock Auto. Parts are more expensive than Small block ford or Chevy parts, but there are not many parts that are ridiculously expensive.

When I built my LS engine I bought every sensor and accessory brand new and spent around $400.

eage8

iTrader: (9)

I definitely don't mind some of the smartest people on the forum discussing stuff I'm interested in in my build thread

8.8 diff and ronin kit is on it's way

eage8

iTrader: (9)

So... in case you haven't noticed I have a really hard time motivating myself to do anything over the winter, even with a 5000W heater in my garage

some minor updates:
The LSD in the diff I got is completely trashed. There is huge amounts of play in the spider gears... which sucks. Looks like I won't be able to get much for it if I sell it... There was also an impressive (1/4") of metal shavings on the magnetic fill plug...

After seeing that (and the oil stains on the side of the diff) I went ahead an ordered new stub shaft bearings and stub shaft seals too (don't come in the rebuild kit I got)

I drilled and tapped the diff vent to 1/4" NPT:


Got one of these for the diff vent, I think it'll work well (with just a 3/8" fuel hose)


There was a Ronin axle issue, which kept me from assembling my axles, but I went over to a friend of mine's the other night that has some scleroscopes (metal hardness testers) and they tested in the good range


All the stuff in my "build list" arrived... except I haven't measured for the driveshaft yet. Which I really need to do to give it time to actually get made... I was trying to avoid mocking everything up by using existing measurements. But I can't find anyone that has the measurements I need, so it's looking like I'm going to have to.

I've been flip flopping about weather I wanted a Eaton Truetrac or a Torsen T-2R... and after talking to a few people recently (including a 7 time autocross national champion) I've decided to send the truetrac back and order a T-2R

I also got some fancy oil (for after the break in):



I also got an automatic FC starter (2 kW instead of 1.2 kW). It's supposed to bolt right into a T2 transmission. Hopefully this helps the car start a bit more reliably when hot.

eage8

iTrader: (9)

oh yeah, and I also got some new Ronin speedworks camber links! I'm super excited about them

I bought a full set. I'll probably start off with the longest ones and see where that puts me. It should get me to right around -1.5* in the back.

FC Camber Links - Master Set

LargeOrangeFont

iTrader: (7)

Nice, you will like the diff once you get it all together.

j9fd3s

iTrader: (3)

the starter makes a big difference in the Rx8, should do the same in the 7

John Huijben

iTrader: (1)

Indeed, the starter solenoid of my RX8 crapped out last week, so replaced the starter and went with a 2kW one. Makes a huge difference! So now I need one for my FC aswell. Anyway progress looks good!

eage8

iTrader: (9)

Last night I tore apart the back of my car

Took a cut off wheel to my diff to do all the needed fin removal and such... (don't buy a battery powered cut off wheel, the batteries don't last long)

pressed in the mazdaspeed mounts into the ronin 8.8 frame.

mocked up the diff and measured for my drive shaft.

looks like 36.5" center to center (of u-joints) or about 6" longer than stock.

driveshaft+parts ordered... I got a little crazy...

Thanks whoever posted this that google found on rx7club:

eage8

iTrader: (9)

Apparently my new driveshaft is back ordered for 4 weeks, so I guess I'll let the cat out of the bag...

This is what I ended up going with:

36.5" quarter master 3" carbon fiber driveshaft with 1310 u-joints (<4 lbs not counting u-joints):
Quarter Master® Carbon Fiber Driveshaft
Carbon Fiber 1310 Driveshafts



Front yoke is a PTI 2603-25
This is the same front yoke mazdatrix uses, and as far as I can tell the only one made:


Front u-joint is getting replaced with a spicer 1310 -> 7630 conversion joint (5-788X)


rear is getting a spicer small ford flange (2-2-939)