Dyno graph of my Z

[Drax240z]

Just thought some of you guys might be interested in seeing the dyno of my car. This is done on my dyno dynamics single retarder dyno. Dyno dynamics units read in general about 17% lower than a dynojet.

 

L28, stock T3, 6psi boost. SDS, 60mmTB, 3" exhaust, 2.5" downpipe, 440cc/min injectors, NPR intercooler, etc. etc.

 

Yes, this is at 6psi.

 

 

198rwhp, 241ft-lbs of torque. This would be about 232rwhp on a dynojet machine.

 

All of the tuning I have done to this point is part throttle mapping, making huge gains in drivability, responsiveness and fuel economy. I want to finish that before I turn up the boost any more.

 

Of note: Look at the engine fall on it's face starting at about 4500rpm... My only theory there is the stock cam, and a smallish air filter. (which I can easily dyno test)

 

Saddest part is I've had the dyno just over a month and only had my car on it for a couple of hours! Damn paying customers keep taking up all the time on it.

[yo2001]

Playing with Loosescrews MS powered L28ET, timing was key to making power beyond 4500rpm.

[akeizm]

Glad to see someone else has a similar dyno graph to mine (very similar setup also at 6psi). But yea thats odd that it falls off @ 4500, prolly timing as yo2001 suggested. Not to hijack but this is my graph which was fun to drive with, but the next day the car decided to run like crap with revs goin down after 3000rpm

[Guest Loose_Screws]

Here's the timing I have setup in MSnS. I would like to add that I have NOT confirmed the engine is actually running the stated timing under load/boost. Although, the timing is spot on for idle and any rpm I am willing to observe under the hood with a timing light.

 

14psi starting at 3,000rpm and up to 3,500 = 28 degrees

14psi and 4,000rpm = 25 degrees (torque peak, which is highest VE and best chance of detonation)

14psi and 4,500rpm = 27 degrees (torque and VE dropping, begin adding timing

14psi and 5,000rpm = 30 degrees

 

And also for the record, I have the same timing for 14psi and up set (didn't update the table in MS) and hit 18psi a few times yesterday while driving! No detonation heard, but power did not feel as good either. It was also 98F ambient and no intercooler can overcome that kind of heat! Time for an FMIC sprayer, get all ricey!

[Guest bastaad525]

eh... EVERY T3 powered L28ET I've seen dynoed (including my own) starts to drop off in torque after 4000-4500rpm. I asked a lot of questions a while back about how to get it to pull past this (mostly focusing on cam upgrades), and the general consensus was that even with a cam, the T3 is just not really capable of continuing to make good power past this point.

 

Good to see some more dyno graphs though, and IF you're observation is correct, about the difference between dyno dynamics dyno numbers vs. dynojets (I've heard it's more like 5%, but still significant), that is VERY impressive.

 

For comparison, I made about 230rwhp at twice as much boost on a dynojet (also on a dynapack which read about 10hp less). I have to say though, even with the improvements you have over a stock setup (I/C, exhaust, big bore TB, SDS), you're talking about 80hp improvement over a bone stock 280zx (Jeff's dyno runs on bone stock ZXT on a dynojet got about 140-150rwhp) at the same boost level. So pardon me if I"m a tad skeptical

 

Someone recently posted some numbers running MS that were also very impressive, compared to the 'usual' numbers some of us have gotten running T3's on stock EFI. At more boost though like low teens.

 

This is really gone a long way to convincing me that the stock EFI must be utter crap... I'd really like to see more dynos of relatively stock setups running programmable stuff.

[slownrusty]

Drax - Why are you running only 6psi? With those 440s, the NPR and SDS etc etc you have pretty sick potential. Great numbers BTW.

 

Yasin

[Drax240z]

Well poor boost control, and some other mechanical issues at the moment. (my turbo is pretty bagged) I had it set at 9psi a while ago but the spring in my grainger valve is wearing out and it seems that boost levels are dropping over time. I haven't had a chance to tune WOT much yet, and I want to do that before turning up the wick. Also I have plans to move my air temp sensor into the charge pipe before anything else, to try to gain some consitancy in my mixtures.

 

Baastad: The 5% number you hear may still be accurrate. All the dyno dynamics operators I have talked to include a 17% inflation factor in their machines, and most do not tell their customers this. They do this to reflect the dynojet numbers, which are unfortuantely "industry standard" because they are the cheapest dyno's available, and therefore the most widespread. My numbers are raw output from my dyno without any external corrections aside from atmospheric. As an aside, I can screw with corrections to get the dyno to read as much as 4 times what the actual reading is. How much do you trust your dyno operator to give you the correct info? Even a well reputed shop near here we've found use this 17% inflation factor, without ever telling any of their customers. I guess if you can make 200hp on one dyno, and 234hp on the dyno down the street, people are going to recommend you use the higher reading dyno. Sad but true. Luckily we are the only Dyno in down, and we can educate our customers, and give them a raw file, and also a file that is labelled as an inflated inertial dyno comparison sheet.

 

Maybe this weekend I'll have a chance to dyno the Z some more. Lots of other cars in line too though!

[Guest bastaad525]

well then my next question would be... if you were to compare to a bone stock setup (I've actually heard of a couple being tested, and always seem to be right in the 130-150hp area) to your setup (stock boost level plus mods you listed), and you're getting approximately 80-100hp difference, do you think this is you reading high, the stock setup's were reading low, or that the mods you have are actually enough to make 80-100 more hp with the stock boost on the stock T3?

 

Same question would apply to your setup vs. my setup. I've actually dynoed at a few different places (the places I go to tend to like to go out of business shortly before I return for more runs so I always end up using a different place), and have seen VERY consistent numbers between the different places and even two different types of dynos I've tested on... starting at about 190rwhp at 10psi, no I/C and way too lean, to 200rwhp at the same psi with an upgraded fuel pump, up to 220rwhp at 12psi intercooled, then up to 233rwhp at 14psi but with my boost controller set up 'incorrectly', with boost dropping approximately 1psi per 1000rpm (problem now fixed, estimating 240-245hp). Each of those tests was at different shops, at various times of day/ambient temps, with different operators obviously, and again, one of them on a completely different kind of dyno (dynapack vs. the usual dynojet), yet the numbers were VERY consistent each time. Hell, even the Gtech testing I did during the short time I had one, closely matched up with these numbers, not in the 1/4 mile e.t.'s (it gave me high 13's because I can't launch worth a crap, it showed my 60' times at like 2.7 seconds), but in the trap speeds, which consistently showed around 106-110mph (I've heard from owners and this article: http://www.caranddriver.com/article.asp?section_id=4&article_id=9380&page_number=1 , that they are actually pretty accurate, though some owners claim the trap speed reads 2-3 mph high, still with my cars known weight of approx. 2600 lbs with me in it, that still puts the trap right where it should be for approx. 240ish rwhp.). All those numbers are usually also very consistent with what other people here have put down on other dynos (or even run at the track) when they've tested similiar setups to mine, and are pretty consistent with what I would expect from my setup, as I've usually predicted within about 10hp what I would put down.

 

So, in answer to your question, I must say I have grown to trust various dyno operators quite a bit to give me the right info and an accurate test and until I go to one and get some crazy high (or low) numbers that just don't make any sense, I've no reason not to.

 

but back to my second question, looking at your setup vs. my setup, would you really feel that your mods would make so much difference as to allow your motor to make the nearly same amount of power at 6 psi, as I'm making now at 13psi? (my mods are listed in my sig below, btw) I know your mods are definately worth more power than my mostly stock setup, but that much?? Or is it possible all the operators on my dyno runs are just setting their setups conservatively... you know they were all more american muscle car oriented shops... maybe they were trying to cut me down to size

 

Hey, on the flipside of my argument, I did go and look up an old issue of Sport Compact Car magazine I have, in which they took a stock Ford Ranger to a bunch of different types of dynos to test and compare results, and they're results DEFINATELY support what you're saying.... they got about 170rwhp/200ftlbs on the dynojet, and only 132hp/169ftlbs on the dyno dynamics... YIKES! That's more than 20% difference.... They then tested the same Ford Ranger in four wheel drive mode and got 150's on the dynojet and just about 100hp on the dyno dynamics... *in shock*. I'm not even gonna say a percent number there For good comparison they actually tested on two different dynojets and the numbers were within about 8hp of each other, and also tested on the dynapack and that was also very close to the dynojets. Well... I know a lot of you guys take anything SCC says with a grain of salt, anyways, but I still put some faith in them.

 

Verrrrry interesting making me want to run out and buy and SDS, 3" exhaust and 60mm TB

[Drax240z]

Sorry bud, that isn't close to my complete "mod" list.

 

8.3:1 compression, N42 head

Mandrel bent 2.5" downpipe, 45* angles

Mandrel bent 3" exhaust, magnaflow straight through exhaust

Medium NPR intercooler

SDS EM-3E

440cc/min injectors

60mm throttle body

Port matched intake manifold

More I'm forgetting...

 

So is 1 extra point in compression over stock, a 3" exhaust, 2.5" downpipe, 60mm TB and SDS worth that power? Doesn't surprise me if they are. Remember that includes removing AFM and corregated inlet tubes and replacing them with mandrel bends as well. Between exhaust and intake flow increases I could imagine a large increase in power from my setup compared to yours, and even with your elevated boost levels.

 

Also at 233rwhp at 14psi I would say you are the abnomoly for power, on the low side. Your 110mph trap speeds would indicate you have more power than that I would think.

 

In the end though, even if you buy all that stuff, tuning is going to give you MUCH more return for each dollar spent than the mods will... (at least once you have something that is tunable running your engine)

[Guest bastaad525]

yeah as I said, the 233rwhp at 14psi... the boost was kinda screwy on that last pull. It started at 14psi at just below 3000rpm, but fell off pretty quickly, about 1psi per 1000rpm, so at the 'usual' power peak rpm of 5000-5500rpm, I was already down about 2psi, and hence, the power peak was very close to the last run I did at 12psi where boost remained constant. I have since set up the boost controller to where that doesnt' happen anymore.

 

This is pretty clearly reflected in the dyno graph, where you can see, compared to all of my previous dyno graphs, the torque falls off much sooner and faster than usual (all other runs the boost stayed the same throughout).

 

So I estimate, if the boost had stayed at 14psi the entire run, it probably would have been closer to 250rwhp. I say it's now at about 240, because since then I have turned the boost down to 13psi. The trap speeds that the Gtech gave me were after I fixed the boost controller, and do seem to confirm that I'm in the 240-250whp range.

 

Anywho, with your higher compression and a few other mods you listed, it does make more sense. That's still a very impressive increase over stock for running the stock boost level. But now I'm not so doubtful of it

 

It also tells me I have a lot of room to improve w/o touching the boost on mine... considering my bastardized crappy exhaust, stock T/B, NOTHING ported... though I dont think programmable EFI is in the cards for me, I do have an '88 Z31 Turbo ECU setup (ECU, MAF, '82 distributor/CAS) just waiting for me to have some extra cash to be installed... that should be worth a few extra ponies just for getting rid of the flapper door AFM.