Dyno Graph for the GreenMachine! Tuning has started.

73GreenMachine

Well-known member
Since I've had the car running for a bit, I decided to go get it tuned. All was looking good until I took the car down to the shop. I got a phone call the next day saying there were some 'problems'. By the way I went to the shop for a full dyno tune and dizzy recurve. My list of problems it as follows:
Wrong distributer (out of an XF 200ci)
Phasing on dizzy is out
Wrong coil (it had a resistor coil in it I was told)
Lean idle jet.
Lean primary jet
Way to rich secondary jet
Advance curve is miles off.

Anyway despite all that, I still got a dyno printout. I currently have 85hp at the rear wheels. I'll show you the graph as soon as Cardomain is working again.

The dyno graph was very interesting as it showed the air fuel mix during the run. It starts off at 14.5:1, goes to 15.5:1 on the primary and as soon as the secondary hits it goes down to 10.5:1 and then slowly up to 11.0:1. I could run a turbo on that A\F!!!

Anyway, I'll get all the stuff fixed up on the weekend and should have it down at the shop Tuesday next week. Unfortunately I will have to remove my XF dizzy and put back in my points unit with the multispark unit.

I am confident that I will at least get another 20hp from tuning, hopefully more. My goal was 120hp at the rear wheels for this setup. It will be interesting to see if I get there.

I should have some more dyno graphs over the next week or two and will post the current one as soon as I can. Tell me what you think.

73GreenMachine.
 
Don't know too much bout phasing on dizzy etc but it sounds the goods. Wont they fix the jets and curve on the dizzy once you get them a new one. Which shop you go to? wasn't Road and Trak was it?
Let us know what she hits :D
 
Yes, I second Steve about the diz. We all knew it was the "wrong" one before you went there. Fixing that will be a step ahead, compared to refitting the old one.
 
Yeah the distributer seems to be the root of most of my problems. For now since I can't afford $300-$400 to get a custom electronic one, I'm having to put in a recon points dizzy with a multispark module. I've also got a new GT40 12v coil on order. It was gonna cost me $600 for them to fix my car, but I got it done for about $75. By the way I went to Bill Towler Mechanical for the tuning because of a friend that recommended me to them. Once I've got the electrical stuff sorted, I'll send my car back, hopefully on Monday. Then theyll redo the jets and recurve the dizzy.
By the way, phasing is got to do with the rotor button lining up with the electrode in the cap when the spark jumps across. It needs to be lined up, but mine was way out.
I'm looking forward to getting home tonight because I'm putting the points back in, the stock coil and rejetting the carby. It should make quite a difference. When I get home tonight I'll post the current dyno graph, and next week the final one. I can't wait to see what power it makes hopefully around 110-120rwhp.
 
Heres the first dyno graph:

616166_83_full.jpg
 
I'd like to see a torque curve.

Extrapolating from what you've got there, I'd punt on a peak of 92-93 RWHP. Not sure how the curve can lift more dramatically - but the main issue is evidently overfuelling in the sense of your fuel curve not suiting.

I think clocking/indexing of the cap is something of a furphy. Yes, have seen some badly aligned ones but the "Tee" on your rotor tip generally takes care of the spark.

Here's my converted dizzy and the break-in one (swap the gear over):



Checked my notes, and rebuild on the electronic one was $225 with the big shaft install, rebush and recurve. Note the retainer collar is shaved down compared to the XE/XF type units (necessary for clearance during installation). The black one is also rebuilt, curved for a stock manual trans 221. That was about $165.
 
Zone out. Diatribe ahead!


I was brought up on Wheels, Car Craft, Hot Rod and Modern Motor. All of those mags published real rear wheel or flywheel Hp readings, not the crap that all the modern dyno prinouts give.

What the heck is KPH anyway. Killer Pascals Hour?

System International units are km/h.

When engines are run, most dynos can calculate transmissions loads, and woprk out actual flywheel hp. Insted, the modern dynos give us this dribble.



Actually, 85 rwhp is more likely to be 108 flywheel hp, or maybee more if the dyno is reading low. Great work from the dyno guys, that's whay we do dyno tuning. You'll get all the hp back.

Well done!
 
I've put in a stock dizzy with multispark module new points and rotor cap and a GT40 12v coil and changed the carby jets as per the dyno graph and it has made one helluva difference! To my utter amazement, I got the whole setup to fire straight up when I turned the key, very unusual for me because something usually goes wrong. Must have been Murphy's day off. Anyway, the idle improved 100% and with a bit of carby tuning. its the best its ever been. There is no more misfiring or flatspots or anything anymore. The thing really flies! At a guess, it feels like I have cracked 100 horsepower at the wheels. I cant wait to get it back to the dyno shop for them to rejet the carby and recurve the distributer.
 
is this a completly stock motor or what has been done? the one thing i find funny is on my dyno graph at 60kph i am making more power than your peak. you are going turbo though arnt you? then it will be the other way around.

Aaron
 
This is actually a worked motor.
Cold air,2 barrel, decked head, ported, port divider, big valves, 3 angle valve grind, unleaded seats, mild cam, full rebuild etc. etc.
Thats whats so sad atm. I was hoping for more like 120rwhp. 85rwhp was a big disappointment considering I was aiming for 150-160hp at the flywheel. The engine was running really badly when the dyno run got done. That power is with a 10.5:1 air fuel ratio and some other bad stuff(distributer related). After Yr12 exams I'm gonna take it back to get tuned since I've fixed it up. By the way it runs way better now than it did on the dyno.
 
The last few weeks have been pretty busy with exams and all that so hopefully I will be able to get it done next week, if all goes to plan. I will post a graph then. I know it has been a long time coming, but since I've got the next three and a half months off, it will get done soon.
 
The tuning is finally getting somewhere. The last few weeks of my holidays I have been earning money at my new work so I now have some $$$ to get the motor finished. Changes since last post include:
Replaced oil and filter with higher grade stuff(Valvoline semi synthetic and Roil additive)
Replaced coolant.
Replaced plugs with Bosch Super plugs(instead of the stock N.O.S. Motorcraft plugs). Gapped at ~1.1mm.
Cleaned up and adjusted entire ignition system and put on some dielectric grease.
Fixed up the hydraulic clutch (needed adjusting).
Took out some oil from my overfull gearbox(I forgot to use the level plug to get the fluid right). This should reduce drivetrain losses.
Got my exhaust system fixed up today so there aren't any holes anymore. I've got my exhaust note back again! :D.
Did some more work on my custom cold air intake. The inside is all smoothed out properly now and flows really well. I still have to put the top of the intake back on, get the aircleaner lid to fit with the new filter, make up a bracket to bolt on the aircleaner lid and give the whole thing a coat of paint. Still a bit of work here.
I also bought a thermofan today which I plan to have installed by the end of the weekend. Its a 12 inch fan with the thermostat controller unit.
I have already booked the tuning, which will be happening next Thursday.
The guy has those Dynapacks which bolt onto the axle. They supposedly give more accurate results than chassis dynamometers.
Even after what I have done over the last couple of weeks, the car feels healthier already, heaps better than my first dyno run of 85rwhp! The guy at the tuning shop thinks around 120rwhp is probably about what I will get with this setup. Anyone else want to take a guess?
 
616166_84_full.jpg


I have another dyno graph. I tried a different tuning company this time with better results. They ended up running stock 137 and 210 fuel jets, resetting the timing to around 8 degrees initial advance and redid my idle speed and mixture. I need to fix two things: one is that I need to plumb in the pcv into the intake manifold, instead of into the top of the carby or to atmosphere. The other is this weird ignition problem I am having. for some reason the coil is firing way more often than it should, causing an incorrect rpm reading on both my tacho and for the dynamometer(5400rpm indicated is really 4320rpm from what I worked out). I think it might have something to do with my multispark module, but I'm still not sure. I think this explains why the dyno thinks I have 4.11 gears(I have 2.92:1) and why my power is supposedly still going up at 5400rpm, at which point it is at 68.8rwkw. Also, there is still more power in the jetting, as it is running about 12.2:1 at WOT because he couldn't get small enough jets. By extrapolating the graph, I worked out a rough peak power of 81.3rwkw or 110rwhp. Next time I go, I want to fix these problems, supply him with some blank jets that I can get and get a more accurate dyno graph and hopefully some more power.
 
68.8 RWKW is right on my forecast 92RWHP. Shame there's no correlation between the dynos; a baseline if you like. You need some sort of a tach adaptor to get RPM correctly with multiple sparks. I think it may have been Fordmuscle83 who sorted this out with diodes and an op-amp.

As X mentioned some weeks back, therre is more to drilling jets than just a small hole. The exit side of the hole is countersunk in effect - this produces more of a fuel spray and encourages better flow. So, caution is advised in the face of this occurrence.
 
Interesting. That means if I dyno it without the module I should get a more accurate graph. I tried taking off the module, but the tacho reading was not different. I still can not find the cause of this electrical problem. Occasionally the car wil run with the correct tacho reading, but not very often. If anyone knows where I can get custom jets for this carby it would be very useful to me. Do DGV jets fit? My air fuel is still too rich at 12.2:1. I still believe more power is in this setup due to the latest dyno graph(it is still going up after 68.8 rwkw). When do modded 200s typically make peak power? I know this can vary with cam specs, but a ballpark figure would be useful. Thanks.
73GreenMachine.
 
If you are getting a flaky tach with raw points, that's pppoint ffflutter. Back to the Bosch electronic !

I think you could bore and bevel your own jets, but just look at a few OEM ones with a hand lens first to understand the principle and mimic it.

Actual power is hard to say because of the lack of baseline. I was only kidding about it being the number I quoted. A good dyno operator can "milk" the car (and they certainly do!) so it looks like they've really done a good job but without bundles of money to baseline things it's all going to remain a little speculative. Your peak HP RPM is probably (nominally) about 200 RPM past the operating RPM specified for the cam, as it will be carded for a 250.

The manifold design thing is another topic again. There are a few "redneck" test options using water, funnels, buckets and a stopwatch but fabrication or casting, and a flange plate to the head, are your sticky areas.

Cheers, Adam.
 
71 to 83 Cortina 4's have smaller jets in there DGAV 32/36 carbs. Those should fit with ease. Sizes are 126 and 137 for primary and secondary, from memory. Air correctors go up and down to match the primary and secondary jets.

The Aussie market 2000 cc 110 to 120 hp Fiat 124/131/132 or SuperBrava jets from the ADF34 will fit, as will the ADAS 32 from the good old 2000 cc Centura.

Basically the same carb as the Falcon's.
 
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