Elliott's94Z

iTrader: (12)

I realize that champ

stephen p

if the thing is pretty much stock that whp seems pretty spot on, for a car that only made 300ish flywheel horse power, and has a 3200 stall? yeah. thats about right. rule of thumb is any where between 15 and 25% drivetrain loss. AND it has a stall? yeah 300 X .15=255 so what's the bitching about? realisticly its more like 15 for a manual trans and probably closer to 25 for a stalled auto

just for reference, on a dyno dynamics dyno (which reads a good bit lower than most dynos pretty much 15 percent lower than a dyno jet. so thats about 30% drivetrain loss on one of those.. well i had a '91 gt stang 331, trick flow twisted wedge heads, solid roller cam, victor jr intake, 200 shot ran through a plate kit sitting under a 750 dp carb.. it had a c4, with a 4k nitrous converter.. ON THE KIT it put 330 whp.. chassies dyno's are heart breakers. that same car went 10.8's a couple of days later..

well, bump those numbers up 30% and it's around 500 flywheel hp. which is right for a 10 second car

stephen p

load bearing dynos are not for "truer numbers". they are for a more accurate tune. there is not near as much load on an engine with the wheels turning 2 free spinning rollers, vs the load on an engine pushing a 3700 lb car.

i have heard about big turbo supra's not even being able to build peak boost on a dyno jet, because the engine is not under enough of a load to spool the turbo completely.

there has to be the proper load, to get an accurate tune, other wise people would just be hooking up a wide band o2 and tuning it in neutral, just reving the engine.

i would not go second guessing the engineers that design dynos. the get paid a lot of money to do their job, and i'm pretty sure the ones that create a load, are built that way for a reason, and not just for the sake of doing so.

96formulabird

that does seem kinda low for the mods u have done. when i first got my 96 formula within the first month i put the magnaflow cat-back on and then had it dyno'ed and it made 220hp and like 300 pound feet of torque. and if i did the math right that is right around where it should have been when it was stock with losing the power from motor to rear wheels. and by the way automatics to the best of my nolidge always put out less power cause they lose more through the tranny. just my 2 cents.

juanito

iTrader: (2)

well i was looking at the lt1 dyno #s in the sticky and saw some running like 270rwhp on stock unmoded car. thats why the question.

AChotrod

iTrader: (17)

Well I think its a little low but not terrible. Mine with a just a B&B cat back put down 280/317 but its a M6

camar0corey

iTrader: (22)

That's really rich. Costing you some power.

stephen p

well one of those cars could have been an m6. or at the very least, not have a stall

Formula350

iTrader: (3)

That was a great reply, and I appreciate you explaining it better than others have in other threads I'm not arguing your information, this is just a personal feeling, I just can't believe that a dyno creator would make one that didn't even remotely reflect the driving conditions :\ I would've thought there was some load put on by any dyno, otherwise the results would be like hitting a golf ball on the moon to promote a new golf club driver. But the results aren't off the charts, so a DynoJet must apply some resistance, or no? I understand the part about using the resistance to simulate pushing the whole car, which is why I just find it hard to believe DynoJet wouldn't incorporate that into theirs A car does roll pretty well though, so maybe the other dynos are putting a bit too much resistance?

My shop at highschool had a dyno, but it was out of commission. It was an OLD style one, easily 18yrs old when I was there, so a good 25yrs now. Teach never really got into the workings of it, but why it didn't work was due to it not having water(?) in it. Either due to a leak in the tank or whatever. I assume then, the water was used to create the resistance? I assume something like a paddle boat wheel and then at X amount of RPMs that it spins translates into X amount of HP. That's just my guess though. It was all mechanical with a HP dial-gauge hanging over the dyno Teach had been working there for about 17yrs at that point and had been working on his T-Bucket project the whole time. It was always parked on the dyno, and he'd fire it up from time to time just to keep it in working order, and so he'd put it in gear and crack it open lol He had huge slicks on the back, they'd balloon out nicely! Anyways off topic :\

Here's my idea for a dyno then: have back AND front rollers. Either the rears connect to the front to spin then, or the fronts are spun via electric motor to simulate the resistance actual driving would result in. Then don't strap the car down tight against the dyno but create a spring/shock type absorber clamping mechanism so it acts more like being on a road, but so it also won't go driving off the dyno lol With that you shouldn't really have a need to huge amounts of extra resistance applied, just a little bit for factor in how much wind would create on a still day with XXX atmospheric conditions applied (since more humid air would offer more resistance due to the extra water in the air). Sound feasible?

Green3spd

iTrader: (7)

A4... Stall.. Cats... and lien = bad numbers...

blake110106

iTrader: (9)

yeah you should be there. I had a buddy that laid 270/297 with K&N CAI, BBK Shorties, TD's w/ 40 series flows, and hypertech chip.

Marc3.4V6

iTrader: (1)

So a stall makes the car quicker, but it reads lower hp?

stephen p

yeah. more parasitec (sp) loss. all a stall does is slip untill a certain rpm. having a 3k stall is kinda like dropping the clutch at 3

jaywalkersw

When you got the tune from madz28 did you tell him you were going to be running the aftermaket MAF?

My guess (in addition to what everyone else listed) is that he tuned it thinking you were running the stock MAF and adjusted the A/F based on the flow from that. Then you switched in a different MAF with a different flow rate and that screwed with what the computer is doing causing your lean condition.

So if you are basically running like you hadn't gotten a tune at all because of that. Get it retuned for the different MAF or switch back to a stocker (if that is what he tuned for) and I would imagine you would regain some of the power you are leaving on the table with that messed up A/F ratio by correcting it.

Now if you told him that you were running that MAF and he tuned for it then ignore this post. Just my thoughts.

Toronto_LT1

iTrader: (-1)

so what is the ideal A/F ratio for a bolt on car??

imnotplutonium

iTrader: (4)

12.5-13 I believe.

why the aftermarket maf? I might have missed it. get a stock one. those numbers don't seem too bad for your setup. but you are def. rich (a/f wise)

exactly like said before more parasitic loss. my full bolt on with a 3k stall and good tune only laid down 290ish hp and I forget torque 3XX ft-lb obviously

PNYKLR-TA

iTrader: (1)

**** red. . . haha!

themack56

iTrader: (70)

juan i told you that maf would make u run lean, before we went remember? another prob is the tune, a mail order tune will never be the same as a street tune or a dyno tune, all cars are different thats why u need to tune for that specific car and the parts u have on, and not for what the mods are only!! i think ur car has about 275 rwhp and 288 to 295 torque, if u tune it properly, i ran rich, and that hurt me, i can imagine what running lean would do, starving the car of fuel lol

nik1703

youve got problems for sure.