PorKen

Those numbers were Standard correction. Roughly 10 higher than SAE.

BTW, my car had Ott-)(, no cat, stock 86.5 big resonators, RMB, crank vent dump, clone chips, and roughly 1° crank cam retard for 298/297 std.

I think the early monster intake is superior, and might have even more HP hiding in it.

Lizard928

As Ken has said that is standard correction,

I also had 1 deg of retard (set right before the run thanx Ken) on both cams, however my breather system has some restrictions as well.

svp928

Just for comparison's sake, my stock 85 made 266rwhp on a Dynojet at Devek days a while back. No mods at all. Taking the lid off the airbox lost 6 hp...So, Ken has found a good one, or mine is weak.

Mike Frye

SVP,

Thanks for the info, I was curious about these numbers. I think the biggest difference in Porken's car is made by the chips. I've read in many places that the 85-86s were really de-tuned when they were stock and benefit a great deal by having performance chips put in. The crossovers are good for 20+ hp without the cats, so your rear wheel hp is not so far off, I think it's just that the 85-86 cars gain a great deal through 'bolt-on' mods.

Here's a case where under $1,000 probably netted Ken (and me too ) almost 40 rwhp without touching the intake at all.

I'm really looking forward to getting mine on a dyno to see where I am right now.

Sorry to continue this hijack. To get back on track, if a similar system were made for my '85 I'd consider it at that price. For under $500, I don't think I'd have to consider for long (hint, hint).

worf928

Call D.R. and talk to him about availability. The 85/86 supercharger kit he showed at SITM has the different bits needed for an 85/86 blackbird.

Shane

My '86.5 put down 281rwhp/278rwtq on a Dynojet. It was stock except for a set of AA chips, cat was in place, nothing done to the engine, which had vacuum leaks, old injectors, fuel lines, etc etc.

So by fixing the vacuum leaks, adding a x-pipe, and some of Kens mods, an electric fan to replace the belt driven one, no smog equipment, my 928 should be putting out over 300rwhp...

AO

I feel the need to post this...

http://www.germanmotorcars.com/Dyno_...0inertia_1.htm

MGW-Fla

Any chance that you may have a condensed version or perhaps your personal summary of the highlights Sir???

AO

Basically it says that the DynoJet numbers will almost always be higher because they are measured using an accelerometer. The SuperFlow and Land&Sea dynos measure actual torque and then use the mathematical relationship torque and HP to calculate HP - a far more accurate and repeatable method for establishing RWHP.

Tom. M

A former PacNW listers 86.5 also put down around 280ish hp on a dyno jet a while back..even beating an 87S4 at that time...pretty impressive..but his had an x pipe and chips....
wanna bet your cat is gutted Shane...?

Either way...the early 32 valvers seem to benefit by tweaking with the fuelling and timing etc..since no knock sensors/timing to take away power like the S4s...just make sure you run the highest octane you can...consequences would be dire indeed...

Later,
Tom
89GT

PorKen

Andrew's link also says that DynoJet uses a proprietary formula to add a percentage for tire or transmission losses, so the DJ will always show higher than the other dynos.

So far as I've seen, properly tuned '86.5s (true dual exhaust), are equal to, or beat, most S4s for HP, but good S4s may have a bit more torque.

I didn't really have any special mods for 298/297std, except for cam tuning, and a PKsn'r. Colin's car wasn't totally tuned, but then again, mine's an auto and his is 5-speed, so I can always fudge the numbers.

Here's what I'd did:
R&R intake
Injectors cleaned
Rotella 5-40 syn, <1/4 on dipstick

Atmo crank case vent from tower, covers capped
Venturi-Y-pipe (Y-connector to brakes) delete
Vapor recovery (carbon cannister) delete
Airpump delete
Cat delete
RMB

Ott-)(
PKsn'r
Clone chips
WR5DC+ plugs
Sync'ed cams to 1° retard (hot)


But still had:
Stock airbox, stock small 85-86 air tubes
8" S4 rear rims, Kumho 712, 36PSI
Stock auto trans cooler system
Big 86.5-87 resonators
Clutch fan
A/C

Jim bailey - 928 International

I have personaly maintained that many dynojet numbers were for one reason or another overstated and at best should only be used as a comparison for the same machine same car before and after. With the additional warning that the fueling needed when fighting the wind at 150 MPH is far different than spinning the drums at 150 MPH... But they are cheap and readily avalable .....like some women I used to know..

Tom. M

And to further Jim's comments..some earlier model Dynojets do a data dump (lose all recorded run data) once the rollers/car exceeds 200mph.... (don't ask how I know that )

later,
Tom
89GT

Shane

I still have the cat and nope it wasn't gutted, it did hawever look newer then the age of the car would have suggested, so it might not have been as "Clogged" as some are out there.

mark kibort

This all boils down to this. Dynojets and mustang dynos all use correction factors and measure HP slightly different. dynojets basically use the change in kinetic energy with the "accelerometer" as was mentioned and mustang dynos measure fixed speed points rapidly to gather rear wheel torque and then with use of the spark signal extrapolate engine torque and hp.

The correction factor is just that, a correction factor. if the probes and temps are not accurate or measuring values correctly, then the factor is just garbage in to create garbage out. best to get both sets of graphs each time you visit the dyno and try and pick days that are simular in temp or season. (i always go in winter on a cool day and summer on a hot day and have been doing this for 6 years with the holbert car) This way, you get a pretty good idea of what your baselines are.

this air box design is pretty cool looking, but i doubt it can produce the gains that are being claimed. ( I would like to be proved wrong, as i would easily pay $700 for 10+hp )

That said, we have seen andersons car run 6 more hp without a filter top on a stock airbox, before he did the CF intake mods.

My car went from no cats and 290rwhp to 335rwhp with only venting the air box, and a set of equal length headers , with 3.5" single exhaust and a RR fuel regulator
Ive done extensive testing with the air box venting and even adding an eRAM to the rear of the air box, that gave 6rwhp and 6ftlbs of torque while also extenting the hp curve out 300rpm. This was not do to positive pressure gains, but we suspect something to do with the change in flow dynamics.

Ive also changed filter hight, used a bell mouthed inlet on the stock air box, as well as a bell mouthed inlet fiter that was mounted directly to the MAF! all of these seemingly positive changes resulted in a minimum of 5hp losses. The only gains were to open the rear of the air box and put an eRAM on it. 5hp for the vent and 5hp for the eRAM. (so, 10hp for both and the cost is only $300, but you need to have the space avalable at the base of the windshield. )
we have also see pressure drops in the air box, on top and below the filter as well as sealing up the filter as we prooved a leakly air box can provide as much hp with a stock filter as a stock air box sealed with a KN filter. However, seal the stock filter and air box and watch the pressure drop go up across it. (ie better filtering, but at a cost of HP due to increased restriction)

the beauty of the stock air box, is that it has a huge air filter and a bell mouthed inlet that draws from a flat bedded air chamber. this is VERY efficient and is used on many a top race car intake design.

Now, this new design is interesting, we just need more testing to see if it is better than a stock airbox and a KN filter.

mk