First time out with the new motor set-up and the new rules package aero changes.

What a fun weekend. Still running in the motor, so went out for first practice on Saturday morning. The weekend was packed with classes so I only got about 10 minutes of track time to set the car up. Issues from first practice....the car had 230 degrees oil temps and would barely clear 175 up the back straight but honestly I was barely pushing it. Dave and I checked the timing (too retarded) and replaced some ducting around the cooler and went out for qualifying.

Oil temps came down to the 210 range (better) but the car wouldn't pull the skin off of rice pudding and I think I got up to 180 on the back straight. Besides the car was not too good around the high speed stuff as I could really notice the difference as the back end wanted to step out a lot.

So as you could imagine I was pretty depressed as the motor should be much much stronger and the handling sucked. I was ready to load up and go home. Dave paused for a second and said, have we checked the throttle opening lately and I said nope, not lately, so we took off the air cleaner mashed the throttle and looked into the carb. WHAT THE F%#@ it was only opening about a third of the way. We adjusted the timing and felt pretty good about the race, at least we would be competitive.


Went out for the pace laps. Started the race in 27th place. The car had tons of low end jam and pulled hard to at least 8000 rpm again. I could really spool the back tires and I was chomping at the bit. The first 2 starts were waived off and the car really didn't like running in the pack as the oil temps were up in the 230 range again and the carb kept loading up. Finally got the green. Jumped the first few cars coming down the front straight. OH BABY we got power now. Came out of 1 in about 24th place and battled through the normal stuff (dirt flying through the air, cars inside and outside of you in the corners, etc...) and finished the first lap in about 23rd. 4 spots in 1 lap great! Came into 2 on the second lap, planted the gas as usual and the front slid out, I lifted caught the slide and the back then came out counter steered to catch that. Car has never done that before?

Went into 3 planted my foot down and the back tires started to spool up really hard and I had to start pedalling the throttle to hook them up. In Turn 4 the car started to twitch and pogo. Between 5 A and B the car started to bounce more. When I planted my foot the car went out in a slide like a Trans Am car. Not good at all. Went into Turn 8 stood on the brakes and the car drifted left and right under braking and when I went to turn in it started to drift sideways at 160 kmh.

Decided to take it easy as the car was really unpredictable and the oil temps were steady in the 230 degree range and try not to crash or blow anything up. Just stroked to the finish, passed a couple of other cars and ended up 19th. My fastest lap was a high 1:41.9, not good at all.

Dave and I had a de-brief after the race and decided that we needed to tackle things in order of importance before Sunday's race.

First we needed to get the oil temps under control. This would be an easy fix. We rerouted the oil cooler lines, made a new line and forced both coolers to do their share.

Second the handling. In checking the travel tell tales on the shocks it turns out that we were bottoming out all 4 shocks at different points on the track. This explained the really funky handling issues as well as the power on drifts I was experiencing. Dave and I discussed the benefits and pitfalls of increasing spring rate versus bar rate and decided to increase the spring rates by 150 pounds all around. We also decided to change all 4 tires to shaved older tires.

Third the brakes. Neede to hook up the power booster again. So we fabricated a vacuum tube from the booster to the intake manifold.

Second race Sunday.

Started the race in 18th as I team had to go back to their spare car. I was really concerned as I had not even driven the car with the higher rate springs or new tires at all. So I decided to take it easy for a few laps to let everything settle down.

Much better start this lap. Passed 2 cars up the front straight, but got balked behind this V6 Fiero going into 2. A stream of cars went past both of us on the inside of 2, I finally got clear of this guy through 4 and set out to catch the guys ahead. I passed 1 car on the straight going into 8 and set the car up for 8. WOW can you say steady state slide Batman!!! The car felt much better on the stiffer springs, but was very much a power on oversteer car now (mental note softer rear bar needed). Finished the lap in about 21st. Oil temps at 180 degrees, water at 210 degrees (cavitating because I am using the stock crank pulley) and stable great.

Put my head down and tried to figure out the car. I was working very hard as the track was cold and the tires were hard. The car had great jump out of the corners and I was going into Turn 8 at a bit above 205. This is about 15 kmh above last year but about the same as it ran with the Mazda ReMan. With the reduced aero grip the car was moving all over.

Drove the car as hard as I have driven it in a couple of years I could even torque out of 5 with an LT1 1999 Camaro. Pretty good torque. Ran decently and ran with cars that were substantially quicker than I was last year so I was convinced that I was down in the 1:37's. The car was moving around really hard and I was having to control the wheel spin with my head.

Finished in 15th overall. Blaaah, not good but where I should have been. Al Balinsky came up to me after the race and said that they had timed me in the 1:41's and I was like "yeah sure" I knew I had run a 1:38 at least. Got the times and my fastest lap was a 1:41.1??? WTF!!!! Only a second faster????

On the drive home I was so down. I had driven that car as hard as I ever had. The engine pulled harder than any motor I have had in the pig. What was going on....

Thank heavens for the data logger and video. Turns out that the car was jumping out of the corners hard but laying down in 4th really bad barely pulling itself out of the hole by the time I was going into 8 and 3. I was pulling the 2nd to 3rd shift about 20 feet sooner and at higher revs, as well the 3rd to 4th shift sooner but the pull from there really drpped until the RPMs climbed back up. This relates to 2 things. First the Holley is just too big for my engine. The rpm's drop to about 4500 on the shift and the carb just won't pull. Driver error in not feeling it and getting seduced with the pull once the engine got over 6500 rpm again. Shame on me.

Second I should be staying in 3rd a bunch more. I was using the gear shift points from the previous motor. WRONG. New motor new gear choices.

Second area is handling. Need to get the rear to bite harder. Will increase camber to about 3 degrees from the 1.5 now.

Third area to improve is tuning the carb. Need to get on a chassis dyno to maximize the system until we can go programeable FI.

Fourth area is the driver needs to shake off some rust. To improve that I am going to do the whole 3 Hour enduro myself.

Thats it. If we have it all correct then we should be fine for the 3 Hour. On a side note, the car looked really nice.

Eric

 

cool. nice update!

just curious, and you may have already mentioned this and i just forgot, but why the delay on the Fuel Injection? you have gotten your intake setup made already, correct?
i'm sure the FI setup will let you tune out some of the driveability/power issues

 

interesting weekend!

Well at least its all in one piece and improvements were made...

Keep us updated Eric!!!

 

Coldfire, we are running Al's Holley setup as we just haven't had the time to piece everything together on the throttle body setup yet. Still need to get a pressure regulator, fuel rail etc... We need to finish the intake off and after it is all installed then go to a chassis dyno to tune it.

The true answer is, yes we can finish it off but I would like to stay married and employed. Al's setup works, is easy to tune and was installed in 4 hours. I just have to get a balance for my car. I might look at using a 600 vacuum secondary to see if it is better.

Biggest issue right now is time and priorities.

We'll get it right before the next race as the rest of the car is bulletproof and working well.

Regards,

Eric

 

ah, i see. well it sounds like if you work out some of those issues you will have a fast car on your hands!
yeah, i can't comment on the marriage issue (i don't mean "issue" in a bad way, unless you want it to mean that, heh). i am single for the foreseeable future :| haha....

 

Eric's hardcore!! Great to hear you had a good weekend... I'm sure you'll be back in the 1:38-36's in no time!

I'm actually surprised to see you still married?!?! Most women would have left their man if they found out they were racing cars! What's your secret??

Lates,

 

LOL, you could sorta say I am hardcore.... I don't think so as I am still married/employed and own real estate. At least half the guys I race against are divorced and willing to live in a basement apartment with lawn furniture to feed their racing habit.

As to my secret, I was racing when she met me and we agreed that this was a big part of my life. I even raced pro for a couple of years and was gone all the time and she didn't whine. Its great when you can have it all. Coolest thing is that she bought me my trailer, most of my parts and gets companies she works for to help sponsor my car. Best of all she never comes to the track, whoo hoo party time with the pit babes (I am one of the least likely to party with pit babes in the world). Speaking of pit babes, I love racing with teams from Quebec.....

Anyways as a totally unrelated side-side note. I found out that after I put on Al's carb setup, faked the S4 ecu by leaving the AFM hooked up (with a rag stuffed in the meter to simulate a wide open throttle), the TPS hooked up and the air temp sensor hooked up, the ignition works great. In fact there is no rev limit with the stock S4 ECU. I am sure I pulled at least 9000 once or twice on the weekend with no break up. Just an FYI for people who care.

 

Did anyone notice when I said I could pull the LT1 Camaro up the back straight at Mosport!!! This is all uphill and it says a lot about the torque characteristics of Joe Ferguson's (RPM Performance) 1/2 bridge engine. I just need to tune it to get the topend fixed up.

Eric

 

Thats great to hear the motor is working well! Oil pressure still good?
Hopefully you can get those ITB's on the motor as soon as you can.....ditch that carb! lol
BTW I have some stickers for the car

 

LOL! Funny since a friend of mine just forwarded a quote he read "Racing is an addiction cured only by poverty."

I'm lucky, the fiancee's supportive of my track hobby and my aspirations (so far). Of course, she's also under the impression that everything costs half of what it really does.

 

what pad / rotor combo are you running?

From what I remember seing (MOM) stock size ....?

 

I run Hawk Blacks at Mosport (lots of time to cool down between applications) and Hawk Blues at Shannonville (higher sustained rotor temps). Also I run lots of ducting.

Yes I still run the stock S4 single piston brakes and rotors. They still work well and save me 75 lbs in a weight penalty. After I get the car running right I expect I will have to switch to the 4 piston set up I have sitting in the garage and add 75 lbs to the car..

Joe, the motor runs great. I will call you with the info.

 

Carbs all the way! EFI is way too expensive!

 

Exactly like I told you. I am SURE that the lil' green FB has been well beyond 8000 more than once or twice.

Saving money for a Street Port...

 

It was nice to get to meet you guys this weekend, and nice to see another rx-7 in touring with us

The car did look really good and sounded like engine was running strong. It should be great fun at the 3 hour endurance race!

 

S4's are rev limited at 8500RPM. Period. They are. Really. I promise. (S5's seem to be limited there too)


BUT the limiter is fuel-based and not spark based!

so that's why you can rev to the sky without "hitting" the limiter. The ECU has cut fuel at 8500 but since it's not exactly supplying fuel to anything and it doesn't stop sending sparks, it'll keep your engine running as high as you want it to (well I'm sure after a point it would have issues, but I'd imagine that point is well past 9000)

I've got one of joe's halfbridge engines in my 10AE and it's FAR more torquey down low than I was expecting it to be, it feels nearly as good as stock from 2k to 3k and better than stock anywhere past there.

what kind of peak coolant temps do you see? at what temp do you start to get concerned for the engine?

 

Terrh and Feds, you guys are right. My ECU used to cut the engine at 7800 rpm, but now it can go to the stratosphere. Jamie I'm sorry to have doubted you, but if the ecu isnt driving the fuel on your motor what is? I believe that the stock ecu cuts fuel at about 7800 with a stock S4 ecu. You may be real lucky and have an ecu without a cutoff. Take it out and sell it to ITS racers in the U.S. I am certain you could get some strong money for it.

Anyways, with water I try to keep it below 210 so I wasn't too worried as as soon as the revs came down the water temps came down. Just a momentary thing. With my Racing Beat crank pulley installed for the next race I expect both oil and water to be well below 190 F. The car ran all day yesterday at 180 F.

Eric

 

I /think/ (but can't prove this) that all S4's limit at 8500 but the tachometer does not indicate above 7800. my recorded RPM's on my old S-AFC always seemed to show ~8500rpm peak and my tachometer has never seen past 7800.

Even on the new motor and EMS now the tach never goes past 7800.

Are you by chance still running the stock gauge cluster? I'm wondering if it's just my car.

 

Hmm, my S4 definitely cuts at an indicated 7800 rpm. Was the 8500 caused by a mechanical overrev during a downshift?

 

Alright, since I'm likely getting a new motor this winter, I will take a trip to the local drags and stand on it and hope for a limiter... All in the name of science!

Actually, there is one fuel related thing that I have bypassed: My ECU does not control my fuel pump. If the fuel cut comes from killing the pump, not the injectors, then that could bypass the fuel cut...

 

fuel cut killing the fuel pump would be a pretty bad way of doing cut, wouldn't it? i mean, even if the fuel pump is turned off, there is still some pressure and fuel in the line, and most likely that could lead to detonation.

 

no fuel cut kills the injectors.

Also, if you shut your pump off while driving down the road you'll notice that you can still drive for 2-3 seconds... if I kill my fuel pump at idle the car will idle for 5+ seconds before it starts to cough/splutter and then die.

my car would indicate 7800 RPM from 7800rpm to 8500. 8500 was not from a mechanical overrev, it happened pretty frequently actually and was probably the leading cause of the demise of my last (stock) engine.

my highest peak recorded revs on the old S-AFC was 9999RPM which was caused by me grabbing 2nd at the top of 3rd. Damn shifter bushings! That was like 2 years and 3 engines ago though.. it didn't seem to affect anything luckily, and thank god that's never happened again. I think my heart skipped a beat when I missed that gear.

 

Factory tachs are a waste of time on older vehicles, no different than speedometers, with age they get very optimistic in most cases. My mustangs tach read 6000rpm when I shifted, after adding a new Autometer tach I was distraught that my car was actually running out of breath at 4800rpm. I see that a lot when I drive for the Paciones on their dyno days. The dyno tells me one thing, the car a lot different.

 

The much less fun, but likely correct, answer.

That said, I will continue believing that my car revs to 12,000 rpm and eats everything short of an FD.