99SS-T

iTrader: (5)

Was in the Mulitmedia section and there is a link to cars modified by Undergroundracing.com. They are all expensive cars that make retarded power on pump gas. Alot of them are able to make 1k on pump gas with a build engine.
My question what makes it so that those engines make that much on pump? I know there is people around here makin alot on pump, but oit seems to be few and far between.
Thanks for any insight!

BadgeZ28

iTrader: (28)

A hell of a lot of dyno time. Getting the correct match of compression ratio, head flow, camshaft, timing and fuel maps, etc. That is what we pay for when we have a shop build our setups.

TT350

A big CID motor good heads and the right cam.

If HP is what your after the cam heads and intake needs run hard up top.

Keep the exhaust back pressure as low as possible.

I’ve had several low 10 high 9 sec cars on pump
that I tuned at the track and on the street to get the best
drivability and performance.

One I took to the dyno for the hell of it.
I picked up 60 hp and about 45 lbs torque over
my seat of the pants/track tuning.

I though that the dyno was the **** until I started
driving it only to find it detonated it *** off with the dyno tune.

I put it back to where I had it and left it alone.
The dyno does not load the motor like driving the car does.

I don’t care how makes the dyno, it’s not the same.
The times slip at the track it your dyno sheet.

Who cars how much power it has on the dyno,
is it as fast I you want it to be?

stevieturbo

Dyno's like Dynapack, Dyno Dynamics, Mainline, Rototest etc will be able to load the engine much harder than would ever be seen on the road.

They will be able to hold any load site at WOT for tuning. You'll never do that on the road


But most engines can make silly power on pump gas. But as race fuel seems to be so easy to get hold of and so cheap, most people dont bother trying over there.

I know on a few guys in the UK making circa 800bhp from 2.2 4cyl turbo engines on pump fuel.

So to do similar from a massive V8, should be a piece of cake.

TT350

Your right, you can’t hold a car at a load site and tune while driving.

A dyno is a tool but it won’t replace driving the car.

stevieturbo

I do agree final tuning must always be on road or track.

But a good dyno can load the car far harder than will be seen on the road.

98Z28CobraKiller

iTrader: (17)

Take a 1200 hp motor and detune the **** out of it. Viola 1000 hp pump gas. LOL

ModularTurbo

iTrader: (14)

You nailed it, you have to build a motor that's over kill to make
safe pump power.

NoGo

iTrader: (2)

Low static compression (8.5:1 ?) + methanol + S/C or turbo I don't think it would be that hard to do.

black98ws6ta

iTrader: (77)

Displacement is king.

NoGo

iTrader: (2)

I would agree with that.

Bigger displacement could mean less boost to reach the same power.

Ball-park, how much CFM does it take to make 1000 HP? Around 2000 CFM I'm guessing?

engineermike

I personally don't consider Meth injection to be "pump gas".

If you're running FI on pump gas, you'll be limited to around 16-18 psi boost unless you have some exotic chamber shape.

Since the boost is limited, and power is a function of NA power and boost level, the only option is to increase NA power.

So, make the most power you can NA (big cid, big heads, big cam, but low CR), then add 16-18 psi.

As someone else mentioned, keeping backpressure down is also key, as is running a larger water/air intercooler.

robert miller

This is what it is all about. But bigger bore = more power if all is eq.

NoGo

iTrader: (2)

I think 16-18 psi is a reasonable rule of thumb for most that read this forum, but you can go much higher boost on pump gas if you just drop the static compression a bit - not really an exotic chamber shape.

A good collection of import cars run boost in the low 20's on pump gas. Did one the other day running 23 psi on pump.

TT350

Pay attention to the throttle in the video,
it stays on the wood a long time before the turbo comes on. But it makes “1200 hp”.

I bet it would be pretty zippy from stop light to stop light.

FYI the UK has a lot better gas the we do.


http://www.youtube.com/watch?v=GzYl3cF-xMU

NoGo

iTrader: (2)

those kind of setups are so much fun to drive (never been in a 1200 HP, but 800 HP was entertaining).

wait for it......wait for it........wait for it.......wait f.....oh jesus.

stevieturbo

What leads you to believe the UK has better gas ?

I'm running 21psi on my LS2 on pump gas with no problems whatsoever.

Ive tuned dozens of Subarus running 30psi with no problems on pump gas. A few Sierra Cosworths too.

And I can assure you, the fuel we get here is nothing special.

99SS-T

iTrader: (5)

Maybe what im tryin to say is if there is a 1000hp pump gas supra with 3.0l, why does 2000 from a 6.0 seem less possible. Im not sayin a stock LS2. I mean whatever it takes.

TT350

It doesn’t work that way.
If 400 hp is enough power to go 160 MPH
then 800 hp will be enough to go 320 MPH right?

I don’t think so!

The smaller the motor the more power per cube it will make.

Max power = max cubes.

One thing the little motor import guys don’t mention
when they are bragging about the big power they are making
is torque,

Mention that word and they have nothing to say, because they have none.

Torque is what puts the smile on you face.

jrocstar

iTrader: (31)

fuel in the us is 93 octane or 94 octane. from my understanding you have access to higher octane at your average fueling station. Top gear has mentioned it several times that american fuel is crap. California I think has even less. 92? octane