RX8 Mini Project

[THE_REAPER]

The motor has about 5k on it since being build. The guy said the old owner had the motor completely build up for street racing before he was rear ended and gave up on it. This motor starts and runs great sounds real mean even with a full exhaust to quiet it down. Every things there to swap it out to mine. Looks like all msd stuff the engine bay has been gutted out no ac no heat nothing but the motor with one thick a$$ alt, water pump, belt looked like 2" i want it lol going up there today try and talk him down a little on the price.

[WE3RX7]

So to update.

Midpipe was installed after having to buy the front gasket, but managing to find a brand new one my gasket bin (I love having this crap laying around sometimes... that was a $32 gasket!)... and replacing ALL the hardware because it pretty much all broke. The sound is "OK" for now. Simply based on the fact that AP uses thin wall pipe I pretty much knew it would be a bit to "tin" sounding for my taste but it definitely drops some weight and has a good noticeable power gain over 7K RPM. The pipe reminds me of earlier FB cars w/ mindtrain exhausts, lol.

After a while though I was concerned about the heat shielding (lack there of) on the pipe and the sound so I wrapped the pipe about 3/4 of the way down. It has definitely helped drop the under car temps a bit and the sound is more muffled to my liking. Not sure of any performance gains but it does help to keep the car cooler underneath. I know some people have issues w/ exhaust wrap, but personally I've never had rusting/moisture problems and if the pipe DOES crack... I'll just weld it again,lol. Dyno on that to come...


Got the coilovers on about a month ago. Still need to dial everything in, especially the rear... but its a big improvement. I did however manage to break a camber bolt and proceed to cuss and scream profanities until my head turned blue because EVERY bolt on the underside of this car that I seem to touch is a time bomb.. I will NEVER buy a northern car again, lol..

The front is set at midway soft/hard and rear is at full hard right now until I get the alignment where I want it and can do some more adjustments.

Next is still finishing up the coil system. I still get a random misfire code from time to time as well that I'd like to resolve. That should be done in the next few weeks. Once those are on, I plan to join Brian (TTT) at some point at KDR for some dyno testing.

Here's a shot of the car as it sits now.

[WE3RX7]

So feeling pretty good with the car minus the lack of suspension tuning.. I started laying out my next plans. I've got auto-x school on the 11th of July and my next race isnt until October (yea.. NASA cancelled a lot of events this year )

My next steps after getting the suspension setup, corner balancing and the coil/ignition squared away is going to be tint. The car is friggin HOT in the summer with black interior!

Then its an accessport. I really want to log some information on this car and get a little more out of it with that midpipe!

I've got the exedy clutch waiting to go in as well, so I'm going to source a flywheel for it and get that in sometime later this fall (if the stock clutch holds out until then). I plan to throw some synchro savers on at that time too.

So by my October race the car should have:
- Suspension done
- Ignition done
- Exedy clutch / unknown flywheel
- TINT
- Synchro saver
- Accessport

I think this will keep me "happy" for a while. I'm hoping with the ignition, clutch/flywheel, AP tuner I can get it up to the 194-196whp range (up 14-16whp from 180whp last time).

Its by no means a monster, but it should be a great cone smasher. The only mods after that might be a catback and then all the safety equip-- seats, bar, etc....

[WE3RX7]

All the above mods would be starting really soon, but today... on the drive home from work.... BAM, limp mode!!!!

I'm so used to RX cars doing this crap it doesn't really phase me anymore, lol. I'm a bit bummed out that I had to limp the car home, but at least the motor survived!

Basically... on startup it seemed great, but after 2min or less the CEL starting blinking and it felt like one-rotor power. I went through $10 in gas in 10 miles!!! It was sputtering and backfiring like CRAZY.

Since I've thrown many misfire codes in the past, I was thinking for sure a coil either finally ate it OR my o2 was bad.

Ran by my buddies shop, because he has all those "fancy" tools, lol.. we pulled everything up and sure enough.. killed the o2 sensor!!

I'm not sure if the sensor just died, or if the heat/wrap from the midpipe killed it. I'd like to maybe pinpoint what may have caused the failure so I can resolve it before getting another sensor in there.

Anyways... I'm on vacation for a while, so the "prissy little bitch" as TTT would put it can sit in the garage until I get back!



Here's a shot of the greatest diagnostic tool I've ever seen a person have at HOME! My buddy runs a shop out of his home at night so he doesn't skimp on the goods. Windows based, full diagnostic tool for EVERY make/model, lol.

[project86]

Originally Posted by WE3RX7

I think this will keep me "happy" for a while. I'm hoping with the ignition, clutch/flywheel, AP tuner I can get it up to the 194-196whp range (up 14-16whp from 180whp last time).

Wait a minute.. you mean to tell me that mazda dynos these at 238 and you were making less than 180 to the wheels stock? that sounds like a bad power drop..........

[reddozen]

He may have some mild compression issues. Typically they're190~200 WHP.

[WE3RX7]

Nope - no compression issues at all at the time of the dyno. The only thing that may have held me back from 181-183whp was the clutch slipping in 4th gear around 7500 or so...

238 is crank power, I had 180whp which puts it closer to 213-220 which is actually ABOVE normal for most stock (at that time) rx8s in '04/'05. Many guys were dynoing in the 170s on a similar dynojet system.

190/200whp is only common on modified 8s, guys with every bolt on and great tuning usually only fall around 210/220whp max with an NA platform. You have to remember that rx8s are a bit finicky on the dyno and even using different dynometer equipment can show a difference of +/- 10whp.

The power numbers arent important, but its getting the baseline and having a healthy motor. Also important to use the same dyno each time you test.

I can post up the chart if anybody wants to see (I thought I already did somewhere...)


I

[project86]

ok i was just curious. i just thought they would be a little more. but no that you mention it i do think i remember hearing that they dyno'd low.

[WE3RX7]

So the problem APPEARS to be coils at this point in time.

The engine has consistent compression and the rear o2 doesn't make sense since it does nothing anyway.

I'm installing my LS2 coils now either way since if it does prove to be coils, this will solve the issue... if not, at least that is done and I can start tracing down what the issue might really be.

I should know by this weekend if the coils solve it... just ordered another set of MSD boots and terminals since I only had 4 to start with and one broke (and you have to buy sets of two with the boots, cant find just the terminal).

Bracket is built and 3 plus wires are complete. I'm taking this time to clean up the engine bay a bit as well though as it was nasty under the airbox and battery tray!

[WE3RX7]

Ah - the coils fixed her right up. I'll post some pics (not that entertaining really) up. Gain about 160 to 180 whp with the LS2 coil upgrade


Now its onto finishing my suspension adjustments, clutch/flywheel and tint lol.

[2gslse]

Originally Posted by WE3RX7

Ah - the coils fixed her right up. I'll post some pics (not that entertaining really) up. Gain about 160 to 180 whp with the LS2 coil upgrade

Sounds good maybe now you can keep up with this dyno queen.

[WE3RX7]

Ah... its so dirty, but affective! I realized after working on the car how much dirt gets in there from the construction around my house! I planned to clean up a bunch of things and give it a good soaking but was rushed for time. I think later on down the road, I'd like to find a new mounting location for the coils, make a straighter shot to the TB, polish the TB and add some additional heat wrap to some of the components. Thats all later, after the FC is done and I'm shifting focus to putting an REW(20B) in this car, lol....

[WE3RX7]

Got a race in before the winter. Everything worked out well. Took the car to full rev limit and the coils didn't miss a beat. Suspension, even with the miles, stills seems responsive and dampens correctly so thats a plus.

Things I need to now.... replace clutch, get new tires, lol... and tint. Its so bright in there!!

[WE3RX7]

Got some work to do over the winter. Trying to avoid getting too crazy as the FC still needs a ton of work:

Tint
Clear corners
dyno
lower coilovers
roll fenders
** mazdaspeed cai **
CS 4pt front strut bar
install clutch
flywheel / counterweight
** recaro seat **
** harnesses **
new tires
corner balance
alignment
install rear strut adjusters
modify splash guards
spline drive lug nuts

My goal is to have this done prior to DGRR and hopefully mostly done by Jan 23 (first auto-x).

[2gslse]

Damn bill, my car is closer than yours and its still on jackstands. I'll call you tom. I talked to the guy w/the '79 in the ad.