Mr_Pieper

I heard Harry Potter swapped an RX8 and everything worked right the first time.

kickerfox

That's another reason the Isuzu is a attractive option. I can get them complete running for $400~500 and parts (including engine internals) are dirt cheap. The range of transmission options also reduce the cost significantly. The list goes on.

You got that right. I figured since this was an "RX-8" forum and not a "Rotary" forum, I might not get such negitive feedback. The RX-8s are also becoming more and more available for the budget racer. I figured some people would appreciate the time and effort I'm going to spend finding an affordable "bolt-in" alternative that didn't completely ruin the car.

Will66

Without wishing to seem obtuse, what's the point of this swap?

If you want a rear drive coupe with a V6 why not just get a 350Z?

Mr_Pieper

I think we have some people missing the point entirely. Every few months there is a new RX8 prophet saying they can save us from our engine and deliver us to the swapped promise land. Every new one has new ideas that are really the same thing we have seen over and over again. Every one of them has either led to a part out or a sloppy conglomeration of parts that barely works. All of this after spending tens of thousands of dollars sometimes. The LS guys are kinda close but can't seem to eke across the finish line.

I dub this one the "Frankenstein truck engine/parts store nightmare version." Good luck to you trying to save us from ourselves with cheap parts from 4 different cars.

No one is mad about getting rid of a rotary in the 8. It's more like, "Isn't that cute. There's another one."

Slidin8

Just make a start already

kickerfox

Clearly you have. Look guys, if you don't like it, quit reading. Is it really necessary to just troll your opinions around? If you don't have usefull input, don't post. Your only cluttering up the thread.

I have. It starts with a plan. No one should go flying blindly into a swap. That's how most of them die.

kickerfox

I believe so. It's a relatively small rack. So is the PS pump. It's also very affordable and easy to come by. I think I have a Miata pump somewhere in the garage. It uses a remote reservoir as well. I had some very heavy 17s on my Miata and didn't have any steering issues.

stickmantijuana

Your clearance issues will most likely come from the subframe, not EPS. Before you buy miata rack, go look at RX8 subframe and look at how EPS is bolted to it. EPS sits slightly in FRONT of the subframe crossmember. You'll gain some space above it with a smaller rack, but I don't think that's what you're looking for. I thought you wanted to mount the motor behind front axis just like the renesis.

kickerfox

I think that frame is called the K-member. The RX-8's rack does sit forward of it but it's higher then the frame itself. The electric motor sits on top of the rack. If the Renesis pully was moved forward it would hit the EPS motor. The front of the v6 pan will be sit above K-member and the crank pully is a bit forward of that. I won't know by how much until I get the engine in the bay and see how close I can get the backs of the heads to the firewall. The RX-8 has a lip at the top of the firewall that protrudes forward into the engine bay. If the heads sit below that lip, there's inches to be gained. It's unlikely I'll get 100% of the engine behind the front axles but most of it will be. According to someones measurements, the 13b shortblock is 27.5" long. Some of it is tucked in the tunnel. Since the rear of the v6 is quite a bit taller, I won't be able to tuck it as far back without serious firewall modification. I don't want the project down for another 6 months while I'm doing sheetmetal work.

This was the best image I could find on the net but I don't believe my sway bay looks like that. The second image is something like what I have in mind. It's from an RX-8with the LSx swap. It's right hand drive but you get the idea.

stickmantijuana

That's how I mounted my engine-with front of the oil pan sitting just slightly over that K-member. Pulley clears the EPS fine (if you have issues, you can always get smaller underdrive pulley to gain clearance), but I had to do this to the firewall to make my engine fit properly. My motor also has modified lower intake manifold to shorten the overall height of the engine even shorter than the renesis's height. I'm telling you right now that your desired placement will require either subframe modification to pull the engine forward, dry sump to get rid of oil pan height, or firewall cutting; or you can do what every one else do and place the engine on top of the EPS & forward another 6-8 inches, which you specifically said you don't want to do. I will tell you again, that the devils are in the details and some details just don't surface until you get started.

stickmantijuana

btw, what's the length of your v6 compared to the renesis? If your v6 is lot shorter than my 3 rotor, you may gain a few more inches.

kickerfox

Your 3-rotor probably has the back iron behind the firewall like the 13b. Here's what I could get so far. I couldn't get to the pan in the vehicle the engine was in. I'd say all of these measurements are +/- 1"

stickmantijuana

mine's about 26 inches. Rear iron was never the problem. Issues were always the intake manifold clearance. Since your motor is 4 inches shorter, you may get lucky, but I doubted. Your intake manifold goes straight up, mine slants towards the front of the engine. You also have head covers sticking out to either side of the engine, and I surely don't have those pesky noisy things I think all your manifold & both of your head covers will hit the firewall. I'll take a picture of my bay in the current position it is in when it gets little warmer tomorrow.

stickmantijuana

here are some old photos I have archived. Brings me back some shitty memories. Sorry to break this to you, I don't think you have a chance making it fit without cutting firewall.

kickerfox

Thanks for the pics. The rear iron won't have a clearance problem. That's not what I meant. What I mean is the rear iron is behind the firewall into the tunnel where it meets with the bellhousing. Because of the v6 heads, I can't put the engine that far back. So even though your engine is longer, the rear of it is back further then mine will be. Rough guess is the trans will be coming forward 5-6" which puts the nose damn close to where your 20b is.

As for the intake. Ignore that plenum of doom that Isuzu used. I won't be using it. If I was any good at 3d CAD I'd draw what I have in mind but I'm limited to 2d CAD and MS paint. The image below is what I have been considering. There's quite a bit of intake runner in the head. The total length is short compaired to to the truck intake but a shorter runner should help bring the power band up. I haven't measured the diameter of the intake ports on the v6 so I can't calculate where it is.



Another option is criss-cross the banks like a 300zx. The height required above the valve cover wouldn't be much more then the runner diameter. It's harder to incorporate a drive-by-wire system into that design.

stickmantijuana

this is exactly the problem. You're now going to make a custom intake manifold for your Isuzu motor? You just quadrupled your original stated budget. What if it leaks? What if transmission doesn't fit into the tunnel? What are you going to do about shifter location? What about the drive shaft? How are you making your PPF and where are you going to anchor it? What if your oil pan sump hangs below subframe? What if your heads don't clear? What if you don't have enough room for your header? How are you going to relocate your ABS? I can continue typing until my fingers wear out. This isn't a $2k project. TRUST US. Hence our original point: you will spend more money than what you're expecting. Questions you need to ask yourself is: #1. do you have the money? #2. do you really still want the Isuzu motor? I'm tired. PM me if you have any specific questions.

bse50

So you're using a V6 because the renesis is dead down low... only to move the v6's power band up again?
You should set your goals before even making plans.

kickerfox

I did my 15psi Miata turbo build on less then $1500 including AEM stand alone. The first build was a Ford Probe turbo on a DIY log mani (free) and I had 6psi for $300. Did I mention I'm resourceful? Yes, if I was buying off the shelf retail products I'd pay an arm and a leg for everything. I pay material cost on water jetted parts like intake, exhaust, and turbo flanges. I'll clone a gasket to 3/8 plate and wa-la $0 flanges. Aluminum elbows are cheap, aluminum tubing is cheap, so is .125" plate for a plenum. Aluminum velocity stacks can be sourced from aftermarket motorcycle/snowmobile Mikuni carb setups for much less then stacks from automotive retailers. The list goes on and on. The only reason people pay as much as they do is because they don't know any better.

The mani won't leak. lol I do quality work. Driveshaft has to be made. Again, I'll make it myself and have it balanced by a shop. Plenty of room for headers. As for things like shifter location... I'd rather not have to fab linkage. I'd like to have the lever straight to the trans but linkage can be done easy enough. It's just more to wear out but if built right it can last. Sealed heims may be my best bet if need be. The Pontiac Solstice tailshaft housing has the shifter pretty far back and close to where I'll need it. As for the ABS, brake line is cheap. ABS control is a bigger issue. If the engine sump is too large, I'll move it, or I'll go to a dry sump. It isn't hard. A power steering pump would probably make a great scavenging pump? I'd have to see if I can find volume ratings. The PPF will take as much work as the engine mounts. It will require a fairly strong bracket and I don't think this v6 was designed to support itself off the bellhousing but I can't see it being much more weight then it would be with the trans supported by the tailshaft in a normal RWD application without a PPF.

All your questions are valid and I've considered all of it. Like I've mentioned. THE hardest part (for me) will be interfacing the RX-8 cluster. If that can't be done I still have many other options. I don't consider it a catch that would stop my progress. FYI the keyless entry, heater/ac, center display, and radio all work with the RX-8s ECU removed. The fuel gauge also works. Temp, oil, tach, speedometer, and -some- of the idiot lights are signaled by the ECU through the canbus data lines. Anyone with MCU skills can code an interface -IF- I knew what the cluster wants to see.

I found a nice image of the Solstice trans. You can see the shifter and hopefully visualize how easy it would be to position it wherever you want using the pivot that's there. The trans-mount holes and shifter mounting holes leave plenty of options to bolt on a fab'd PPF mount. The shift shaft (being pulled in and out of the tail shaft housing) is moved like a FWD shift linkage (not cables). A shifter from an MX-3 or Protege (and many others) could be mounted directly to the tunnel of the RX-8 and linked to the shaft of the Soltice trans. Pulling the shifter back pushes the rod in. Moving right turns it right, and left turns it left.

shadycrew31

iTrader: (6)

This thread is hilarious...

You sure are going to an awful lot of work to troll us...

Mawnee

Yea, I've been having this feeling as well. We've had a rash of threads like this on the corvette forums lately.....

I don't want to be fast anymore - Corvette Forum

olddragger

iTrader: (3)

jfyi --when we added an extra front pulley to drive the pettit s/c system for our 13msp engines --we still have 1- 2 more inches of clearance between the new pulley and the eps etc. That extra pulley sticks out from the oem front pulley about 3 inches or so.
Since you are so resourceful you may have an easier time by adding the rx8 trigger plate to the front on the Isuzu engine? If you can do that then the instrument cluster etc will work.

kickerfox

An awful lot of work - yes. To troll you - no

I'm attempting to solve as many problems as I can first before I start. Some call it preparation. Heard of it? Or do you expect me to dive head first into a project this large and wind up stalled out with no options or solutions like the other swap threads you keep complaining about?

Wiki:
In Internet slang, a troll (****.: /ˈtroʊl/, /ˈtrɒl/) is someone who posts inflammatory, extraneous, or off-topic messages in an online community, such as a forum, chat room, or blog, with the primary intent of provoking readers into an emotional response or of otherwise disrupting normal on-topic discussion.

Some people are doing a better job of meeting that criteria then I.

That might keep the 8's ECU happy enough to run the cluster but there's more to a parallel ECU then that. Two ECUs is probably twice the mess I'll already have to deal with. lol I will consider it as a last resort.

Here's some measurements I took from an R154 Supra turbo trans. A friend of mine has one kicking around so I thought I might as well measure it. Probably useless at this time, maybe someone wants to know. The main body of the trans is 10" wide.

shadycrew31

iTrader: (6)

You make my head hurt, just go buy a grand am and be done with it.

kickerfox

I believe your pain is self inflicted.

olddragger

iTrader: (3)

i understand prep work, but a test fit will give you much more info. Time for the wrenchs?