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Should I Be Disapointed?

Musky

By Musky,
in Engines & Forced Induction

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Musky Experienced

Musky

Posted
Posted

Ok guys, I just got my car back from the tuner and it feels a little slower than when i took it in despite gaining 20 more hp.

Its got highflow inj, 040 fuel pump, fmic, zorst, adj cam gears, z32 afm, splitfire coilpacks and slide highflow turbs.

It made 265hp at 14psi. It previously made 247 and was tuned with more boost but the actuator was failing (this was with a different tuner). As well as the tune it had a new rocker cover gasket and spark plugs put in.

The compression was tested too and apparently its a little low on a couple of cylinders, would that have any effect on the output?

Im just stuck as to what could be wrong. The tuner said it was a fair enough reading and that was to be expected with the turbo setup as he doesnt rate highflows much. I dont know too much about these things but ive seen peoples results with these turbos on here and they're making more power than I did with less mods/boost...

Any ideas or am i crying over spilt milk?

post-25513-1285221590_thumb.jpg

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https://www.sau.com.au/forums/topic/337910-should-i-be-disapointed/
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Harey Veteran

Harey

Posted
Posted

Nah mate I wouldnt be happy either. Thats only ~210rwkw, some people are making that with stock turbos. For that power you dont even need injectors, afm etc

I do not know the specs of the slide hi flow turbos?? The curve looks like its doing what it supposed to be doing. I think the turbo is holding you back.

Ryno Experienced

Ryno

Posted
Posted

I wouldn't be too disappointed if I were you, as 14 psi isn't a great deal of boost... My car makes only 240 rwhp at 12 psi (HKS GTRS) and it's not until it's at 17psi that it comes alive.

The other thing is that his dyno may read lower than others, it's really only a rough guide to how much power your car is making and not worth losing any sleep over.

jrm Veteran

jrm

Posted
Posted
I wouldn't be too disappointed if I were you, as 14 psi isn't a great deal of boost... My car makes only 240 rwhp at 12 psi (HKS GTRS) and it's not until it's at 17psi that it comes alive.

The other thing is that his dyno may read lower than others, it's really only a rough guide to how much power your car is making and not worth losing any sleep over.

240rwhp sounds incredibly low for your setup, even with 12psi. My car (R34GTT), with a 3" turbo-back exhaust, Blitz FMIC, factory turbo & untuned ECU is seeing 245rwhp (182.7rwkw), peaking 8psi in the mid-range, and 7psi by peak power (factory boost control). Got more than a few people surprised (This was on an SAU:SA dyno day, on what people say is an accurately reading dyno)

Ryno Experienced

Ryno

Posted
Posted (edited)

This is my point exactly... Each Dyno reads differently. At a SAU dyno day (Unique Autosports) a few years back, my car put down 10% more power than when it was tuned, and it was a hotter day!

I think a lot of shops are quite happy when their dyno's read high, as the customer goes away happy.

The proof is when you take it for a drive... The 255's on the back of my car won't stick to the road until 3rd gear, that's a better feeling than some numbers on paper.

Edited by Ryno
toffy Veteran

toffy

Posted
Posted (edited)

why is it that everyone measures their cars performance by peak kilowatts? , shouldn't you all be reading torque figures a lil bit harder?

ok so in laymans terms as far as i'm aware , measuring peak power is like measuring the length of your penis , measuring torque is like measuring the girth.... ask your missus which she prefers

Edited by toffy
PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

Power is a direct relation to torque and RPM. So yes while the peak kw figure aint that important, in this case it very much is as it's not like the rest of the curve is completely flat to make up for it.

Nah mate I wouldnt be happy either. Thats only ~210rwkw, some people are making that with stock turbos. For that power you dont even need injectors, afm etc

It's actually just below 200kw which is even worse....

The OP's power is very low indeed and Ryno's 12PSI GT-RS power is incredibly low once again but i'm assuming it makes 250rwkw on 17psi judging by your signature? Which in that case it is fine, but funny how it makes so little power on 12psi (mine used to make 310-320hp@14psi).

Anyway the OP's car obviously has a problem. Either the engine is hurt, the tuner has tuned it extremely safe due to thinking the engine is hurt or something else completely.

Edited by PM-R33
t_revz Grand Master

t_revz

Posted
Posted

My 33 was making around 266 with only Pod, Fmic and boost at 10psi. Last run before rebuild running simular mods to you was 335rwhp at 15 psi with Gcg High-flow and i had only 120psi compression across the board as all pistons were broken...As Trent said the tuner could be over cautious

Ryno Experienced

Ryno

Posted
Posted (edited)
The OP's power is very low indeed and Ryno's 12PSI GT-RS power is incredibly low once again but i'm assuming it makes 250rwkw on 17psi judging by your signature? Which in that case it is fine, but funny how it makes so little power on 12psi (mine used to make 310-320hp@14psi).

My power figure at 12 psi was low by comparison, because it was run on a different dyno. On that same dyno it only put down 235rwkw at 17psi, yet the car is putting out more power now than when it previously put down 250rwkw on a different dyno (I know this because my peak injector duty is higher than it was back then, with the same A/F ratios and timing).

Like I said earlier dyno's are just a guide, and the only way to compare two cars is to line them up back to back on the same dyno, rather than getting all hot and bothered about what figures people post on here.

Edited by Ryno
GHOSTrun Mentor

GHOSTrun

Posted
Posted

OP I'd be pretty disappointed with those results.

My unopened RB25 with stock turbo @ 1bar made 305hp (~230rwkw)

-injectors

-fuel pump

-z32 afm

-powerfc

-ebc

-3" straight through exhaust

-3" fmic piping with 100mm thick cooler

(engine compression was 160psi across the board)

toffy Veteran

toffy

Posted
Posted
Power is a direct relation to torque and RPM. So yes while the peak kw figure aint that important, in this case it very much is as it's not like the rest of the curve is completely flat to make up for it.

wasn't particularly aimed at the OP , but i disagree with your statement (so many variables but i cbf explaining , it was more of a joke). ok for the OP since i can't make jokes round here: odds are the tune is pretty conservative/average , if your engine is tired (low compression for what ever reason) I would expect your tuner isn't going to lean on it very much because he wouldn't want it blowing up a day/week/month after tuning it as it could give him a bad rep. Now it may have went well on the 'old' tune but there is a possibility that the 'old' tune caused your engine to be in poor condition now.

For your own piece of mind , take the car to another reputable workshop (with a dyno) and get them to give it a power run , get a print out of it and get their opinion on the tune .

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

You disagree with my statement on power being related to torque and RPM? Enlighten me please.

Bare in mind i'm an Engineer and unless you can prove physics wrong I don't think you will get very far...

Edited by PM-R33
toffy Veteran

toffy

Posted
Posted (edited)

no, that the peak power is important in this case. i can argue if you want me to? only from sheer boredom though :blink:

edit: ok i'll bite, kinda , but only because i have nothing better to do :D . Yes what you said is right , but the amounts/values can be altered by things like air flow, ignotion timing , cam timing , amounts of fuel at whatever rpm, type of fuel bla bla bla , which is indirectly what my previous post was about?

Edited by toffy
hypergear Grand Master

hypergear

Posted
Posted

If few cycs just "little low" then probably won't matter too much. Also depending on the high flow profile that you have which seems to be running too hot and out of puff up top.

Dyno it again with 3inch metal intake and dropped exhaust, see if that makes any difference.

Harey Veteran

Harey

Posted
Posted
edit: ok i'll bite, kinda , but only because i have nothing better to do :blink: . Yes what you said is right , but the amounts/values can be altered by things like air flow, ignotion timing , cam timing , amounts of fuel at whatever rpm, type of fuel bla bla bla , which is indirectly what my previous post was about?

All those things are inputs to how much power/torque you make. They are irrelevant once you have a dyno sheet.

Torque (lbft) = Power (hp) * (rpm/5252)

They are directly related.

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