APEXMX5

Hi folks, I am Dan Hillsberry. I'm from Boise, Idaho, I am a 10 year miata owner/racer, I have owned my RX8 since 2006. I'm 30 years old, a Journeyman carpenter, qualified mechanic, and now an engineering student. My racing experience started with many years of AutoX and Hillclimbing, and the last several years of competitive drifting. All in my 300hp/tq 1990 miata.

So that is who I am and my background, and from here on this thread will be about the LS1 swap into the 04.

This project will be done within the limits of the 2011 FormulaD rule book.

The LS1 I bought is from a 2002 Camaro SS. 29,000 miles.
I got the entire drop out with body harness, PCM the works!
The T56 is beefy but I am sure I will miss the wonderful shifting action
of Mazda's trannys

Why LS1? Why not (insert any rotary engine config here)?
because of cost. If I could choose between 2 rx8s of equal performance and reliability and cost. 1 being rotary and 1 being piston, I would choose the rotary option.

As all of the above factors are not equal, they have dictated my choice. This is my apology in advance for not "keeping it pure" and for "removing its soul".
/purism discussion


Current status:
the entire Renesis drivetrain is removed, and all related wiring is removed.

I sold it all to a friend of mine who is an RX7 guy. We are putting it in one of his 1st Gen cars.

The RX8 is moving to the side while we fit the Renny in his FB.

pics, sorry about the quality
This first one is from the ebay auction where I bought the engine.


dusty from high speeds on dirt roads lolz






Sooo much wiring to go through! lolol

pdxhak

iTrader: (2)

Welcome to 8club! I believe there have been two LSx swaps here so you might want to check out those threads. Good luck!

mscamp02

iTrader: (3)

there have been a few good lsx swaps here, might be a good source to reference to hopefully stop a few headaches for you.

Good luck and cant wait to see the project progress!

APEXMX5

Thanks guys!

Yeah I saw a thread here. was a silver car I think. I took some ideas from it.

TeamRX8

iTrader: (25)

Hopefully you own a triple layer nomex driving suit, just sayin'

APEXMX5

I know right?

fire suppression system, FIA seats, and now my helmet is out of date lololol. All the safety stuff that is required gets expensive but it is good stuff!

Oh wait you meant because I am gonna get flamed... dont care bro. I got bigger fish to fry then forum opinions. I am more concerned about winning.

TeamRX8

iTrader: (25)

you and me both, bro. - major props on that attitude alone

Dirt_Nasty

iTrader: (2)

Welcome to the club. I can't wait to see the progress.
I say it's your car do what you want with it, just do it well no matter what. Hope everything goes smootly with the build.

APEXMX5

Thanks for the props and well wishes guys. I look forward to getting to know this board.

This weekend should be interesting with the mounting of the 13b-MSP in the FB. That car is gonna be a pretty cool DD!

I purchased another RX8 front body harness because I had to sell the original with the engine. I hope to be able to have full function of the headlights, wipers, turn indicators, etc... Having the complete harness should make this nearly headache free.

The Reverend

iTrader: (1)

good luck sir!

olddragger

iTrader: (3)

have you considered a carburated engine for this swap? Sure would simplify things?
But if you want the LS design--its a good engine.
The biggest problem with dropping an LS into this chassis seems to be the steering? I dont know of anyone that has done this in which they didnt have to make a major change there?
Dry sump or not? It will be interesting to see how you address that.

By the way BHR sells some upgraded axles if you end up with the need.
We drop a lot of LS engines into the RX7 chassis here in Ga. But the 8 is a different beast
kudos to ya dude--watching with interest.
OD

APEXMX5

there is really no way around having to relocate and possibly change the steering rack.

I am wondering what happens when the EPS computer loses signal from the PCM. I assume it will go into a default mode of either full assist or minimum assist. It will no longer be able to vary the assist based on vehicle speed. I can control the supply amperage and voltage with my own device to reduce the amount of assist if it is to high. But if it is too low I dont know what I could do. Also there is the possibility that it wont assist at all.

It seems everyone else just mounts a camaro steering rack. The only reason I am hesitant to do this is because I dont know the camaro's steering ratio and I dont want slower steering.

APEXMX5

Yes, it would be more simple but I dont like carbs. I was raised on EFI and learned carbs later in life because I had to. I never fell in love with them.

raknaks

Good luck and will be watching with great interest!!

APEXMX5

So this weekend was pretty good. We figured out fueling for both cars. The LS1 and the Renesis both want 60 psi. a corvette style fuel filter has a built in regulator and only 1 discharge port to the fuel rail. perfect for use in the rx7 with a walbro 255 LPH pump.

I will fit a walbro 255 in the rx8 pump housing and the stock regulator is for 60 psi already. I will block off the return line on the fuel rail and be done.

The rx8 cluster will be used in the Rx7 and will be lit up like a christmas tree. MPH, RPM, Coolant temp, etc... will function. almost every warning lignt will be on lol. TPMS, EPS, ABS, etc...

We will modify the renny mount brackets, use the stock mounts, and weld mounting platforms to the frame rails for the mounts to bolt to. the engine is tall and will be as low as we can get it. the following pictures are of what we are working with.












On a different issue, handling. we have all read the threads comparing engine weights, renny vs. LSx, 20b turbo vs. lsx, 20b vs renny etc...

there are a few things that change the numbers. The weight of the LSx AC comp, bracket, ps pump, bracket, idler pullys, and bracket must be subtracted from the weight figure of the LSx. I will not be using them. This means that the AC condenser will also go away as will the renny's dual oil coolers. The battery will go to the rear of the car, and the cross support bar that the airbox and other bits bolt to will go away too. (not the one that the hood latch bolts to.)

All this weight is in the very front or nearly there, and all this weight (not the PS pump) was in the car with the renny. So the amount of weight gain over stock is much less then others have calculated. also the predicted issue of too much weight up front ruining the balance and raising the polar moment is much smaller than predicted. the estimated higher CG of the LS is also helped by relocating heavy battery which is mounted high up and forward in stock form.

When you consider these comparisons but with 20b turbo vs. LSx it seems the LSx is actually the one with the advantage.

In conclusion I expect handling to be very easy to sort out. and any issues to be minimal.

(all PS related statements assume my success in being able to retain the stock EPS rack)

9krpmrx8

iTrader: (46)

Nice, it would be cool to actually see one of these make to the track.

renesisjim

iTrader: (3)

I agree. I'm looking forward to this especially since an 02 slp Z28 SS was my last car before the 8. I miss my torque sometimes but wouldn't give up the handling to go back to a camaro.

TeamRX8

iTrader: (25)

somebody brought an early model Miata with an LS1 swap to the autox yesterday. very professional looking swap, but it was basically helpless with narrow Miata wheels and street tires. except for the V8 rumble and tire spinning mania it was a total sleeper in appearance

APEXMX5

That look really good!

haha stock wheels arent gonna cut it with a high power miata!

I will be running something that will make a 275 have just a small bit of stretch.

olddragger

iTrader: (3)

if you are going to be pushing more than 400hp I dont think a 275 size tire is going to hold you on corner exit. Most Vette's in this area with minor mods are running 315's. Some have tried to shave points off their TT scores with 285's --275's and it did not work. this is with a rwhp of 450 or so.
OD

APEXMX5

well there is a new tire size rule in FD this year. It limits maximum tire width based on vehicle weight. If I want to go wider I will have to be heavier. I will be around 400 for a while I get the rest of the car up to par.

copypaste from ziptied

On the tire rule, I can't exactly point out to what cars this will affect the most, but like I said, most of the field complies with this rule, and the ones that don't are WILDLY outside of spec. Some of the major offenders would need to add 500lbs of weight to their car (which they can't) or go down FOUR tire sizes. The aim of this rule is to get tandem runs back into the same ballpark of speed, so that we can have more close, exciting battles. The way I came up with these numbers is a simple equation for theoretical grip, I just doubled the width of the contact patch (2 tires) and divided it by the max and minimum weight for each class. These are the ranges below with the grip number ranges on the right in parenthesis.



2000-2199lbs up to 215mm (.195 to .215)
2200-2399lbs up to 235mm (.196 to .214)
2400-2599lbs up to 255mm (.196 to .213)
2600-2799lbs up to 275mm (.196 to .212)
2800-2999lbs up to 295mm (.196 to .211)
3000-3199lbs up to 315mm (.197 to .210)
3200-3399lbs up to 335mm (.197 to .210)



Also one interesting note that I can tell you is that the highest ranked driver with the least grip (by a ton) is Chris Forsberg.

Salamanth

With regards to the power steering rack, I am 99% sure I've read in multiple places that various RX-8 engine swaps have used the FD rack, especially in drifting, since it has more readily available parts to increase steering angle.

Not quite sure where I caught that, but it was in reference to either bergenholtz racing's car or Mad Mike's BadBul.

Props to you if you can get the 8's EPS working though.

wankelbolt

iTrader: (21)

^^^ And the seagull poster strikes again.

APEXMX5

I think you must have misunderstood my post. There were no calculations in it at all. just comments about various pieces of weight that in my case cant be counted in the overall weight of the dressed LS1, and comments about bits of weight that were in the car in stock form that will be gone or in the back.

no numbers, no calculations. Just me saying the way I plan to do it.


on the tire numbers and grip levels, that was not my post, just a direct copy paste.

If there is an issue I am over looking, please feel free to just identify it instead of just hinting at it. I want the end result to be the best I am capable of producing.

YaXMaNGTO

Good luck with build.
I'll be following your progress with much anticipation.

Just to make you aware if you weren't already, Hinson Super Cars (not a sponsor of this site) has been working on an RX8 kit for an LS1 swap. Unfortunately, it looks like it might have stalled considering the lack of updates on their site. You still might want to chat with them...