So I recently finished my 99 turbo gsr and took it to a local shop to have it dyno tuned. Well he took it to a dyno that he had previously never used (first problem). On top of that the shop who's dyno he was using were a bunch of hot rodders and had never ran a 4 cyl or a FWD car on this dyno. (2nd problem) Long story short, I got a good tune as far as A/F ratios and a super smooth power curve but the dyno showed 200 whp at 10psi. I have read alot about the dyno dynamics dyno being a "heartbreaker" and turning out really low numbers but im looking for some input. The car feels good and pulls hard. boost around 5500 rpms. I understand the dyno may read low but 100 whp low, WTF. Are there settings on the dyno that could be killing my numbers? I tried hard to not skimp on my build and i feel like i have the right components to reach my goal of 300whp. Where am i coming up short. here is my setup:

-Bone stock GSR block.
-Brand new OEM head gasket
-ARP head studs
-Stock GSR head
-Edelbrock victor x Mani
-Edelbrock 65mm TB
-Walbro fuel pump
-DSM 450's
-2" hot side IC pipe, 2.5'' Cold side pipe
-Mishimoto intercooler
-SP Log manifold
-SP 3" downpipe
-2.5" cat into 2.5" Tanabe SHM exhaust
-Turbosmart 38mm WG 7lb spring
-Forge MBC
-Precision 6152E
-P28 Tuned with Chrome

 

NEVER SAID 440cc WONT GET YOU 200whp. IF YOUR NOT GOING TO READ THEN DONT RESPOND TO MY POST. no point of even postin

 

with 226whp @ 8psi
i was at 96% duty cycle with a ls motor

but shouldnt be the problem since u claim to have good AFR

 

take it to another dyno 1st then proceed from there. post up ur dyno graph. i would get rid of the cat

 

450's are good to 300-325

they are definatley not limiting him to 200whp lol

 

Well im not sure on the injectors, my tuner says he has made over 300whp on a couple b16's with 450's. My AFR's are between 11.6 and 11.8, alittle on the rich side but pretty safe i guess.

My tuner is taking one of his own vehicles to this dynamics dyno that he has previously dynoed on a dyno jet. He says he is going to play with settings and see if the #'s get better. I think i will cut out the cat, free up the flow alittle.

Here is a crappy photo of the dyno sheet. The the pink line (246.8whp) is at 16psi the green is at 10psi

 

Who cares about numbers...if the tune is good and the car is fast then there u have it

 

Check your compression and then if it is alright then take it down the 1/4 and report back with the slip. That should tell you the power you make, not the inconsistency between dyno's - chassis dynos are tuning tools first and foremost.

 

Catalytic converter FTL.
Take it down the 1320, your trap speed=universal dyno.
BTW, I made 393 to the wheels with RC 450's 3years ago.

 

Dyno's lie, trap speeds don't..

I'd ditch the cat and don't bottle neck your exhaust. ex: 3" to 2.5". Change the exhaust to 3".

Just to see if that's were your problem lies, I would do a open dp pull on a different dyno. I think you might be surprised.

I would also be very interested in what kind of timing your tuner is running.

It seems to be its either a restriction issue or timing related.

Don't listen to anyone on here that has grammar issues using tat this and tat that. What the #uck is 'tat'. Shouldn't this kid be surfing Disney's forums or something?

 

i agree with everyone else, take it to the track and see what you trap.. FYI i was trapping 114-115 with about 315whp on (DSM 450's) in a full weight DC2 about 2700lbs...

i went to the dyno once (Dynojet) put down 270whp@12psi was a bit baffled but o well.. went to the track the new day and i was trapping 118-120...idk what was wrong but it wasent my car

 

Hey thanks for all the response. I was discouraged about the #'s but it feels and runs good. I think i will change out the exhaust and get it down the 1/4!

My tuner is baffled by the low numbers as well and has basically offered to get it on the dyno again once he gets it dialed in. Now that u mention it, i seem to remember him saying he didnt adjust any timing...WTF. should i make him re-tune this thing.

 

Here is what my tuner said today when i e-mailed him i think i just need to get it to the track!!


"Yeah the dyno was reading really low. Car feels like in the 300's, feels real smooth. I don't even think those guys know how to run the dyno. Your car was the 1st boosted import car on their dyno ever. Timing was about .75-1 degree per lb, really conservative. A/R was in mid 11's. I've street tuned a similiar set-up and did a dyno pull @ 10 lbs, he pull 280whp on the dyno jet. With your bigger turbo, 10-12 is around 300whp. 18-20lbs is around 400whp. Bigger the turbo less lb = more hp

My old lsvtec with 62-1 @ 24lbs was 480whp
You have a good set-up. "

 

A bone-stock Z6 SOHC with a 57trim will make over 200whp at 10psi. This turbo can flow 25% more, and is mated to a better motor.

Although the injectors can easily support 300whp with a good pump, you DEFINATELY skimped on those. It may be possible one is running lean, which will definately kill power. The only other issues I could see would be a plugged/melted cat, or a colapsed flexpipe. Both would majorly restrict flow.

 

11.6-11.8 is not rich my no means, deffinatly safe. Its what i like to have mine at, hell a little richer wouldnt hurt.

 

The cat and the exhaust are holding you back a bit. Also, if this was my setup, there is a lot I would change. Personally that SC61 is far too large for a stock block setup. Anyway, the exhaust and the small cold side piping are slight restrictions on your setup which could cause the lower numbers. Boost pressure, even on that large of a turbo, is still determined by the amount of resistance in the system. With such a restrictive exhaust and piping, you're hitting 10psi, but aren't flowing enough air to make more power. With a more free-flowing exhaust you should see a gain in power at the same boost level. Also, i didnt see an AFR plot so the tune may be pretty conservative depending on how comfortable your tuner is with that stock block...there are a lot of variables that could lead to low numbers...

 

1st thing.... i made 450 to the tires through a 2.5inch exhuast.


2nd thing. to the OP. does your vtec enguage ? seems weird you got a pretty big dip in your curve...

 

I assume vtec is kicking in. Is there an easy way to tell. I cant really hear/feel the cross over cause it is set at 5200 which is right where boost comes in. My tuner said they played with the vtec point and ended up leaving it at 5200 cause it helped spool the sc61 alittle quicker. He said if we moved it up the dip would go away but turbo would be even laggier.

 

Are you sure its not a D16Z6?

 

haha...they'd be low #'s for single cam.

 

If you dont like the spool of your SC61 i will gladly trade you my 57 trim!!! full boost by 4200rpm! i want an SC61 for my stock block so i can make some moarrr power

 

You're not missing anything - 200whp on a DD is about 300crank HP. Keep in mind 4wd cars are spinning 4-wheels, 4 rollers. Your car is not only dragging rear rollers but your rear wheels at all. I'd say your car makes about 310-320crank HP. Don't believe the dynojet #'s they are all BS...

Doesn't the dude have a decoupler for the rear rollers? I know most of the Mustangs dynos do.

 

imo, the turbo should be spooling alot faster than that. i would expect full boost by around 4500 rpm.

any check engine lights on the car ?

when the vtec enguages the car will get noticably louder. you can see if the ecu is activating vtec by probing the proper wire @ the ecu with a test light. (would be best to have a friend along, so he can do this while you keep your eyes on the road.)

 

We own a DD and they read lower then your average dyno. Depending on what kind or corrections they added to the dyno, we've seen anywhere between 12-18% diff from a jet. Spool also could of been affect by how much load they threw at the rollers.

 

come on bro, my 74mm turbo hits full boost around 6000