Dyno Results are in, Pics - Holley Systemax Kit :sad:

[Ekliptix]

Dyno Results are in, Pics - Holley Systemax II Kit :sad:

89' 5L w/ 90,000km
-Holley Systemax Kit II (heads/intake/cam)
-Crane Gold RR's
-BBK Longtube headers, H-pipe, flowmasters
-70mm Holley TB
-75mm C&L MAF w/ 24lb injectors
-lightweight flywheel, alum driveshaft, Tremec tranny
-Electric water pump, electric fan
-Superchip Custom Tuneable chip using a R/T interface

247whp @ 5100RPM
275tq @ 4000RPM

We were on the dyno for 3hrs trying to figure out why the numbers were so low, but ended up nowhere. We ran a test on each cylinder to check for a differential but they were all even.

It falls on it's face after 5200RPM and sounds weird after that point. One weird thing is that the MAF voltage climbed like normal until 5200rpm, and then stopped going up. This is where the power begain to drop hard and a different sound could be heard. We couldn't figure out if the MAF was the problem, or if it's voltage thing was a biproduct of another issue.

We spend 3 hours on the dyno trying to figure it out, but I think this is jus the power that it's going to make. We suspect its that the Holley heads are not the best.

Yesterday I raced my old Mustang (335whp on a dynojet, 102mph trap).
It begain to pull on me a little at about 65mph, but we were even untill then.

Oh, and I'm losing that big tach. It's 2000rpm off anyway.

 

[cardudeusa]

Wow, I've always heard the holley heads flowed really well! Theres got to be another problem.

 

[Ekliptix]

I've found another thread on here where a guy w/ a similar setup to me had numbers even lower.

My plan is to try to get hold of a different 24lb MAF to try. That'll tell me if mine is busted w/ that voltage thing.

Next I'll be replacing ignition parts. It's got those iridium plugs which I'll be changing to copper ones.

 

[cardudeusa]

I've found another thread on here where a guy w/ a similar setup to me had numbers even lower.

My plan is to try to get hold of a different 24lb MAF to try. That'll tell me if mine is busted w/ that voltage thing.

Next I'll be replacing ignition parts. It's got those iridium plugs which I'll be changing to copper ones.

Whats wrong with iridium plugs? I thought the were the best thing you could get?

 

[bluevenom867]

I would change the C&L to a Pro-M I personally thing they work better,also make sure your mass air meter is calibrated to your 24lbs injectors and that your comuter is also calibrated to your injectors and meter.

 

[91five-o]

Hey bluevenom 867, what do you mean when you say: make sure your computer is calibrated to the 24#ers. What does this entail ? I swapped up to 24# injectors, and put a 24# sampler tube in my 73 C&L meter. I didn't do anything with the computer. What am I missing here.

Rick

 

[TIMMY2734]

computer does not have to be calibrated to your injectors......

 

[james51381]

my stock systemax kit was 275rwhp and 305 tq, with a spun bearing and no tb or chip. My numbers are about average with the kit. The came really shines from 2800 -5800. I would check your MAF. good luck

james

 

[stangbear427]

Whats wrong with iridium plugs? I thought the were the best thing you could get?

They are, if you drive a Honda. For a Mustang, just plain old Motorcraft or Autolite plugs work best. Anyone who tells you different is trying to sell you something, or convince themselves they didn't waste their money on them.

Ekliptix- Obviously I think you should take out the iridiums, you may be surprised what happens. Otherwise I'm betting on the MAF too- have you run it for codes? I suspect that the 350HP they advertise is possible with the Systemmax kit is flywheel, not rear wheel. Of course, it should still be over 300 regardless. How does it feel on the street? Any drivability issues? I know Holley had some problems with the heads when they first came out, but I was under the impression they fixed it a long time ago. What's the likelihood you got yourself one of the older packages? Good luck.

 

[Michael Yount]

Given the type of dyno it looks like you were on, your numbers don't look all that bad to me. However, you haven't given us much to work with. What kind of dyno was that, Mustang brand? If so, they're gonna be much lower numbers than a dynojet - I think you know that already. What did your a/f ratio data look like? What was the HP curve doing after peak at 5100 - drastic drop off, or was it basically flat up there? Did the power curve fall flat on it's face at 5200 along with the differences in sound you've described? What happened to a/f ratio at 5200?

Like bluevenom, I think you need to take a close look at your maf situation. You need to be sure that the voltage/air flow transfer function of your maf matches up with the transfer curve the ecu is expecting (stock HO transfer function). Calibration of an maf for different injectors is usually done with a pretty simple voltage adjustment based on a simple ratio of injector size - 19/24 in your case. But the transfer function is a map that corelates a certain amount of air flow to a certain voltage reading. The computer is expecting a certain transfer function based on the stock HO maf function (the Cobra has a different one, the Lincoln LSC had a different one, the Lightning had a different one, etc). Some transfer functions used by maf manufacturers don't match up very well with what the computer is expecting. If that's the case, it can affect output, drivability, etc. And it seems you read more posts about challenges with C&L meters than with ProM meters. But the folks who really have things tuned use a chip or tweecer to actually alter the ecu and input the actual transfer curve from their specific maf -- the data is usually available from the manufacturer; at least I know ProM provides it.

 

[stangbear427]

That's the deal with the C&L- it re-uses the stock MAF electronics, unlike Pro-M who sends their meters with a newly calibrated plug and play sensor. So theoretically, the C&L shouldnt offer any discrepancy with the tranfer functions and the computer. Some people make out fine with the C&L sample tube/stock sensor setup, and some... well...

 

[Michael Yount]

Bear - what's up? Understand about the C&L function - problem is, meters get passed around used like they're truly a "plug and play"; many times/many people don't know what kind of transfer function they've got in their meter because they don't know what it originally came from. Mystery, layered upon mystery.

 

[blown93feature]

I can tell ya from expierience that almost 95% of my previous problems with stalling driveability,surgeing idle and everyother thing came from maf and it was a new 73c&l set up for the injector size I was running and we could never tune the car.I bought a 77 pro-m and the car is perfect and as far as plugs are concerned,I couldn't agree more with the autolites(1.17) a piece or motorcrafts (1.03) because if my blown 11 sec ride has no problems than youre's won't either.

The only way your computer in the car would have an effect is with a chip that doesn't work well with the mods and is throwing bad or incorrect demands on parts that are also not working together.

 

[stangbear427]

New avitar Blown93? Good show. Love Motorcraft plugs.

Mystery, layered upon mystery.

So, ignorance isn't bliss after all?! Well there goes the neighborhood!

 

[N8Miller]

something sounds a bit off with your tach too. if anything, the stock one should be off. Mine is more accurate than the stock one.....but 2000 off by the aftermarket one....seems odd.

check your maf too.

 

[stangbear427]

Yeah, what's up with that? Where are you getting your tach input from? That thing should be dead on. What brand is it? I'm surprised mainly because it looks like an Autometer Sport Comp in your pics. The factory tach is at least 200rpm low, guaranteed.

 

[BlueOvalStangGT]

Kinda OT, How come different dynos make differnet power levels?

 

[stangbear427]

They use different methods to determine them. There are three main designs for Dynos, and they are pretty different. Kinda like a Power drill and a hand screwdriver. Both do the same job... one is just more versitile and efficient.

 

[Michael Yount]

Different dynos don't "make different power levels" - they just produce different numbers. The Dynojet brand is an inertial dyno. It has a big arse set of rollers (8000 lbs.) and it's software knows how long it takes to accelerate that mass to a certain speed. By comparing how long your car takes to accelerate the mass to what it's been programmed for, it comes up with your HP (so even that is a calculated event), and then it calculates Torque based on the power level and the rpm. The Mustang brand dyno is an eddy-current type unit. It has the ability to electrically "load" the roller wheels - and based on how your car pulls against that load, it determines HP, and also calculates torque. Some units hook directly to the hub (you take your drive tires off), and based on a hydraulic "brake" pulling against a strain gauge (the 'brake' translates a torque or twisting force into a pulling force on the strain gauge) - they directly measure torque and calculate HP. In my opinion, those types (directly measure torque, calculate HP) are the ones that are most likely to deliver an accurate measure of things. But they are the hardest to find - I know there's not one anywhere near my area. The vast majority are the DynoJet (inertial) or the Mustang (eddy current). They're very useful for doing comparitive changes on the same car/same dyno/same operator/same ambient conditions. But beyond that, there's not much way of knowing how truly accurate the numbers are - and they shouldn't be used for such, although nearly everyone does. There's a great article in last month's HotRod magazine (should be online by now) about the different types of dyno's and how they work. There are so many variables that it's nearly impossible to reasonably compare one car's output to another's even on the same dyno. Thing's like how the car's strapped down, a few pounds difference in drive tire pressure, or even the quality of the tires can result in 10-15 HP difference. My younger brother just recently helped with the Mustang dyno test of a drag racer 68 Chevy pickup - blown big block and power-glide. In a before and after test where nothing else changed (they were monitoring air temps near the air intake, oil/coolant temps) they picked up 18HP by tightening the tie down straps on the rear axle by one click on the adjusters. How is anyone gonna compare numbers with variations like that?

 

[IndyBlk5.0]

My car fires right up every time, no surging, no dieing, stays perfect at idle. I'm happy with my C&L 73mm, they really arent that bad IMO