Extractors (or Headers if you Prefer) Dyno Test on 170

[fxp]

Interesting day at the exhaust shop today. Went in to get a set of Pacemakers fitted, drove out with a set of Wildcats. Bloody Pacemakers didn't clear the starter. Supposed to be made to fit for XPs (essentially the same as a roundbody except the steering box is on the wrong side). Anyone else had this problem? I thought they were only a problem for the US 250s with the low mount starter?

Anyhow I had the car before and after dynoed to test the gains (if any) of the swap. Unfortunately they only did the before in L (XP 3 speed autos only select Lock or Drive). Also they've shown the torque in Lb (I assume this is pound - force feet?) and the x axis in kph instead of rpm. They did do the after run in both L and D so I've got a better measure of the power at the bags (not much ) but can't give you a measure of what the improvement is.

In L the headers showed a 10.5 HP gain from 30.9HP to 41.4HP (thank god they didn't show it in KW!) which is a close to 33% as makes no odds. With the peak moving from 52kph to 60kph. Hmmmm sounds like an awful lot don't it? Torque went from 360lb to 415lb at essentially the same peaks. That's 15% torque gain. But again hmmmm. If it's pound force feet then thats 490Nm to 560Nm? Can someone explain these numbers? Is the fact it's being measured at the wheels giving a multiplication factor over the spec 156 foot-pounds (measured at the flywheel I assume).

The after run was repeated in D. This gave a peak HP of 58.5HP ! (should I get a special set of guard badges made up with that number on em? ) Unlike the runs in L the curve is pretty flat across the top with 56+ HP from 108-138kph (peak at 126kph). Really wish I had the pre header data to compare it to, but

Enough of the numbers. I will say that the seat of the pants test was . Really noticed the extra impetus, especially at take off. There could be a little bit of placebo effect here, but the car really does feel like it's not struggling to get moving anymore. Getting up to freeway speed on the on ramp seemed noticeably easier than yesterday and it felt like it wanted to drive through the 70mph I usually cruise at whereas before that required the boot put in.

Background info: I did a full service on the car yesterday in preparation. New coolant, , new air filter, new oil and filter (Castrol Magnatec 10W 40), new plugs (NGK AP5FS gapped to 35 thou), Dwell set to 37deg, timing to 12deg BTDC, idle to 800 rpm.

 

[addo]

What part of the starter did the Pacemakers interfere with?

 

[fxp]

They didn't say exactly. I can only assume the front underside. I'll try and find out. They also said it was very tight on the steering box.

The shop rang pacemakers and got some cock and bull story about "having had that problem with cars using Cortina starters". Maybe some PO has put in a Corty starter, but it looks pretty much identical to the starter in the photos of my workshop manual.

 

[addo]

My personal experience with Pacemakers, was that you had to remove the cylinder head to fit them on our cars... Maybe the exhaust fitters were part-time bricklayers?

Older starters (Lucas usually) are fatter but SFW?

 

[rommaster2]

Thats pretty good news, kinda makes me feel alot better about wanting to put some headers on my 200. I might turbo it with a small turbo though, so maybe pass up the headers *shrug*.

 

[fxp]

Dyno sheet here:

 

[69Falcon]

Funny numbers on the torque, you're most assuredly not getting 360 to 415 ft-lbs of torque (which is how we yanks typically measure it). If it was, you'd be twisting axle shafts!

 

[pedal2themetal45]

Funny numbers on the torque, you're most assuredly not getting 360 to 415 ft-lbs of torque (which is how we yanks typically measure it). If it was, you'd be twisting axle shafts!

I'd have to agree that almost as much as my 466 BBF.. its most likely in KW's what ever that is I thought Killa watts but thats electricty.
Tim

 

[fxp]

Yeah I know those are just plain crazy. Even in Nm it would be insane torque.

The engine stock is rated at 156 foot pounds (I'm assuming like the hp measured bare engine at the flywheel) so I was assuming maybe there is a multiplication factor at work here because it's being measured at the wheels? Maybe multiplied by the diff ratio? 415/3.2 would be about 130 ft-lbs which seems much much more likely.

Can anyone explain?

The assumption on why the power gain was so huge is that the cam gains weren't realised with the stock exhaust so we're seeing the extra potential of the cam in that number. Good theory or bad?

 

[wallaka]

It might be because it was measured in low gear. I thought they were usually measured in whatever gear that's closest to 1:1.

 

[fxp]

Yeah considered that, but the run in D (1:1) was still over 300 ft-lbs. Surely a mild cam and headers aren't going to give twice the stock torque.

 

[Anonymous]

its most likely in KW's what ever that is I thought Killa watts but thats electricty.

Tim, that would be kilowatts (kilo = 1000)

and

746 Kw = 1 HP

It doesn't matter whether electricity or not, it's still a maeasure of work.
Most engines not rated in USA are rated in Kw (kilowatts)

 

[falcon60]

Actually 746 Watts (not KW) = 1 HP. 746 KW would be nearly 1000 HP.
To convert (roughly) : KW X 1.33 = HP.

Terry

 

[Anonymous]

Yes, Terry...you are CORRECT.


I was thinking off somewhere else while typing!