DRFTGTO

Hello i was asking a few of my RX-8 owning friends what the best sight was to find out info about RX-8s and they all agreed upon RX8club

Ok now here is my question, one of my friends just went past 40k(with no warranty!) on his rx8 and is now looking into swapping an LS1(is between 2jz and LS1 but among our friends we have a lot more LS1/2s then 2jzs, one in fact and not boosted, so we are all kind of leaning toward the lsx powerplant) motor and trans into his 8. Granted this wont happen immediatly as we are saving this project for when we both(and a few others) have much more time to devote to this. But what i would like to know is how much power can(or should i say torque?) the rear end components take? For ex: axle, differential, axle shafts etc.

Or would we have to replace all of that?

Also the suspension would be upgraded accordingly, and most importantly the tires (Either RE-11s or maybe RT-615s as me and my other RX8 driving friend seem to be very impressed by them so far) On a stock suspension how wide of tires can be fitted to the front and rear? He has stock wheels and will stay like that for a while for that sleeper look, for a while at least.

Im looking forward to this project and learning what is needed to accomplish it, thanks

nuke0907

iTrader: (2)

there is a thread somewhere about someone already doing that swap. just search around a little.

for tires you can easily fit 275's all around. i have 265's all around now, but i wish i would have got the extra 10mm. the best way for this is to get 18x10.5" with a +43 offset.

DRFTGTO

That thread provided no useful information, the only other thread i could find that relates is the Twin turbo LS7 swap, but thats way more power then a practically bone stock LS1 puts out...way more power....

and wow 275s??? Holy crap i cant even imagine, my friends handles so good with 235s as it is

Brettus

iTrader: (2)

I don't know how much power an ls1 makes but I can tell you that a bone stock Renesis turboed to 11psi 330whpish is a beast .
Putting a v8 in a RX car is just wrong IMO

But for what it is worth I know turbo guys make over 350whp and 260lb ft and use stock rear ends with no issues to speak of

DRFTGTO

well you see the stock LS1 comes with more torque then that, and instant power on demand

DRFTGTO

my mistake i think i found the thread you speak of

Brettus

iTrader: (2)

did a quick search and came up with this :
Your LS1 is going to be slower than a turbo renesis .......

"roughly 290hp and 300 ft/lb torque to the rear wheel for a manual equipped LS1"

Mawnee

Admittedly it will get far better gas mileage though

DRFTGTO

Hmm i think i forgot to add 04 LS1, and idk what kind of LS1 you have there but my buddy has an 02 camaro thats Auto and no mods and he saw a lot more then that


Oh plus since the clutch will most likely be upgraded a 150 shot will make all the diffrence

Mawnee

Even the 04s made just shy of 300hp to the wheels in a manual.

Brettus

iTrader: (2)

that was whp not flywheel hp - this is more from the same article :

How much power? Try 345* horsepower and 350* ft/lb torque at the flywheel (roughly 290hp and 300 ft/lb torque to the rear wheel for a manual equipped LS1).

LS1 Specs
Type 5.7 liter V-8
Displacement Displacement 5.665 liters or 345.69 cubic inches
Horsepower * 305 Z28, 320 SS/WS-6 @ 5250 , 345 Corvette @ 5600 rpm
Torque (lb-ft) * 335 Z28 , 345 SS/WS-6, 350 Corvette @ 4400 rpm
Max. Engine Speed 6000 rpm

Brettus

iTrader: (2)

Can't argue with you there

I just think people who do motor swaps without exploring what can be done with the Renesis do themselves a disservice .
Adding a well setup properly sized turbo to the renesis adds all the power you could wish for while retaining all the other wonderful traits of the stock car

DRFTGTO

Ok you got me, a DEAD STOCK LS1 makes less power(but still more torque) then a TURBOED rotary, a 150 shot could change that around real quick, but none of this is getting anything solved, these are two opposite ways of going fast, he wants torque and power and demand (kinda got infected from all the times we swapped cars lol) plus it has greater potential and MUCH better responsiveness to mods, i didnt start this thread to debate going turbo or swapping that decision has already been made.

And simply because the hp is slightly lower does not automatically make it slower lmao there are more things then just hp at play like gear ratios, torque, when the power is available and other such conditions, but dont worry you will get your chance to prove us wrong if this ever gets done in the first place haha

Brettus

iTrader: (2)

see above - but yeah you are right , sorry for the threadjack

Mawnee

I would check out the Rx7 forums as well. This swap has been done quite a bit in those and would probably be a good source for info on driveline parts and compatabilities.

DRFTGTO

No problem all opinions valued, especially when coming from someone who actually has a turboed RX8 and not one of those guys "well this one guy with a turbo..." haha


Oh and about the RX7 forums they mostly talk about swapped FCs, very few components are the same if any in an RX8 i believe

RufusVonStorm

If you're building a drag car you could find a better/faster/cheaper/ and lighter chassis to mount your LS1 into. If you want a well balanced good overall track car with good power do the boost. Also the motor swap will not be an easy project, and will cost more.

blackenedwings

To agree with Brettus, a LSx engine swap will be heavy, and generate less power than a properly tuned FI Renesis, and its particularly distasteful for us rotary heads. That being said, if you are going to do the swap I would not rely on the stock RX-8 drivetrain components. The best people to ask on this forum about some suggestions would be "rgonza" and the other guys who have done major engine swaps (20B etc) putting out larger horsepower/torque numbers just to be safe. The power delivery of a LSx engine is very "stump pulling" and wouldn't surprise me if it broke the stock components pretty quickly.

DRFTGTO

He already has the car so buying something else will not be cheaper, and the suspension will be upgraded and the LS1 does not really add that much weight to upset the balance terribly but he will try to fight it with the help of some carbon fiber