Holy cow it's fast!! Three cheers for MFI!!

dtw · 01-17-2004, 04:14 PM

My engine is finally dialed in! I had been having a lot of trouble getting the ignition and injection dialed in correctly, and must admit that I began to fear damaging my engine (LOTS of backfiring and poor mixture). I threw in the towel and had the car towed over to my mechanic. Lo and behold, he fine tuned the injection and ignition, and fixed a couple of, ahem, small mistakes I had made, and the car...made no power. Ooops.

We both tackled it this afternoon and after lots of troubleshooting, decided the injection pump was garbage. I ripped the pump off and replaced it with a nice T pump I had on the shelf. Cleaned up the spark plugs just in case, timed the pump, fired up the car...backed the car out of the parking lot...hey, it's not lugging and complaining!

Feeling suddenly optimistic, I found a hole in traffic and dumped the throttle...the car took off like a rocket ship. It threw me back in my seat, completely by surprise. I must say that the power produced by this hotrod 2.4 exceeds my wildest expectations. Throttle response on the injection is absolutely amazing - I've never driven a car like this before. Torque is great down low and power comes on at 2200 and is quite linear up to 4,500, at which time the power really comes on. This is the first mechanically injected car I've driven that is properly sorted out - it is truly a great system. And actually, this 2nd pump hasn't even been fine tuned yet. I don't know how I'm going to make it to 1,000 miles without taking it out to redline - this engine really wants to scream. I have no idea where peak HP is made with my setup, but it sure isn't 5k. Where did your car peak, Tyson, if you're reading this? ? I gotta go find your dyno sheets.

Sorry to babble like this but it's been 4 years since I've owned a Porsche that moves under it's own power and I'm just a bit excited!! Time to sort out turn signals and brake lights and get this break-in period out of the way!

Tyson Schmidt · 01-17-2004, 04:21 PM

Hey, isn't this the engine that you copied from mine? She hauls ass, doesn't she!

Remember, break it in HARD! Lots of full load, full-throttle acceleration, and deceleration to use gas pressure to seat the rings.

I think my peak power was at 5,800. But it stayed up there pretty nicely, and only dropped a little all the way to 7,100.

I have no complaints with my little 2.4, except I wish I'd just bit the bullet and built a 2.4S-spec, due to P.O.C. racing classifications.

But the nice thing about this spec-motor, is that there are no holes in the power band. Very driveable.

Do you have a factory sport muffler on it yet?

Tyson Schmidt · 01-17-2004, 04:23 PM

Here's the link to the dyno results on my motor.

Reseda Dyno Day - Results

Halm · 01-17-2004, 04:35 PM

Nice Dave, very nice.

Congratulations, for sure. A few of us are going to have a "dyno day" in Mooresville in a couple of weeks. Want to join us?

dtw · 01-17-2004, 05:15 PM

Tyson,
Yep this is the motor I built that's almost exactly like yours! As of today it even has a "T" MFI pump. Not that I didn't believe you, but yes, I'm blown away by how nuts this motor is. It hauls ass! I'm not going to drive it now until I can get all the light and signals working, then I'm going to give it hell - there are some great backroads proving grounds around here, plenty of elevation changes. I'll give her hell.

Hal - Wow, that's about 150 miles from my house. How soon? If I can get the car roadworthy and inspected by then, I'll be there. What are the fees?

Halm · 01-17-2004, 05:18 PM

Dave, I'm going to send you a PM in a few minutes.

NY65912 · 01-17-2004, 05:20 PM

Congrats, ain't nothin like a sweet running P car. Now go out and enjoy!

dtw · 01-17-2004, 05:29 PM

Thanks Hal. Oh and Tyson I forgot. Yes, I have a factory-style sport muffler that the race shop made for me. $185 for fat, FAT sound and free-flowing exhaust. I was shooting some great flames out of it today before we leaned the rack out. The sound, as you know, is indescribable. Stay tuned for audio in the coming weeks...

Jim Richards · 01-17-2004, 07:04 PM

Ya Dave! That's some great news. Looking forward to the audio.

FA-18C · 01-17-2004, 07:25 PM

Dave - any updated pics of the entire machine?

Tyson Schmidt · 01-17-2004, 08:23 PM

Dave, did you use T throttle bodies? I'm just curious, because mine were necked down to 29mm where they meet the cylinder head. My intake ports were also 29mm. I opened them both up to 33mm.

I also just got done swapping out my T plastic stacks for some early magnesium E stacks. They are just about perfect diameter for my set-up. I'm hoping that my power curve will drop off less than before at high rpm. Those plastic T stacks are pea-shooters!

If I remember correctly, you built the exact same engine I did, except for slightly different cams. Mine are late-E cams reground by Elgin to early-E/Solex with a 102deg. lobe center. What are your cams?

dtw · 01-17-2004, 08:24 PM

Chris! The whole machine is pretty ugly still - - Jamie/jpnovak and I have been so busy, we haven't been able to get our schedules together to finish the bodywork. However, I'm trying desperately despite my extraordinarily busy schedule to get the car completed before the Rennsport Reunion. I'm hoping to have it in the paint booth sometime in February!

Jim! Thanks man. It was great meeting you and your wife last month.

jpnovak · 01-17-2004, 08:32 PM

Oh, so now its my fault that POS is ugly. Maybe you can run away from its own looks with that fancy new motor of yours.

that's so cool its running well. Sounds like you made more progress than I did today.

The welder is ready and waiting...

dtw · 01-17-2004, 09:33 PM

HEYYY. I said WE'VE been busy...I guess there have officially been two weekends you've tried to come down and I've been working.

Did I mention the motor is running strong? And the exhaust sounds amazing?? No?

FA-18C · 01-18-2004, 05:00 AM

I know everyone is waiting for more updates from Jamie as well. Shoot in the time it has taken me to straighten out the S bumper I got from him he has completely rebuilt his car. I feel like a glacier! BTW Jamie, I've got a young LT who is getting out and heading to NRL this spring to work. Smart kid, hope he does well.

makaio · 01-18-2004, 05:22 AM

$ years is long time to go without the Porsche drug.

cegerer · cegerer's Garage

OK, so what's the magic formula on your's and Tyson's motors?

2.4L
Pistons?
Solex cams
MFI
heads?
????

Paul Thomas · 01-18-2004, 08:42 AM

Dave, sounds great, i may have to come over and check it out.

Whats the 411 on that muffler?

Paul

power · 01-18-2004, 08:54 AM

Congrtats!! I think the more testimonials I hear about the modified sport exhaust will eventually wear me down into making my own out of the spare muffler sitting around..............

Tyson Schmidt · 01-18-2004, 08:56 AM

Quote:

Originally posted by cegerer
OK, so what's the magic formula on your's and Tyson's motors?

2.4L
Pistons?
Solex cams
MFI
heads?
????

Well, the 2.4 E was already a pretty good motor. Many magazines got better 0-60mph times with it than the S.

Our motors have higher compression, (mine is 9.8/1) and Solex cams. Solex are pretty near S cams, if you look at the lift and duration, especially compared to the later E-cams. Late E cams are much milder than early E cams.

I used 2.2T pistons, (pocketed to clear the hotter cams) which are 8.6/1 in a short stroke motor, and 9.15/1 in a long stroke. My heads were flycut 1mm, and I played with deck height to get the desired C/R.

I think it's just a combo that really works, and has a fantastically wide power band for a small motor. Feels like a 3.0, but with a less bottom end and more top end. And did I mention the throttle response? And the sound?