Caspers latest visit to the JMM Skunkworks.. - Page 4

Casper · 24-09-2005, 09:15 AM

Quote:

Originally Posted by useless

Yes it does mate..ask Brenden next time you see him.Stall speed is higher in a heavier vehicle.More weight=more stall speed to move the thing.Not my opinion mate ...just the physics of the stall speed vs weight of car. Stall speed is the speed at which the stallie overcomes resistance.A heavier car will need the stall speed to be higher because the stall must slightly higher to move the heavier car.

Stav, I think your confusing stall rpms with flash rpms. Stalling, the car is not moving, it doesnt even know it can move. You are talking about the flash rpms, the moment you release the brakes and the car attempts to move.

kooky · 24-09-2005, 09:23 AM

OT post Gaz what on earth happened to have you driving a 6 cylinder?

Laminge · 24-09-2005, 09:26 AM

Need more funds to keep HO team financed!

kooky · 24-09-2005, 09:28 AM

Quote:

Originally Posted by Laminge

Need more funds to keep HO team financed!

OK pardon my ignorance ummm..... team HO???

Apologies casper

:

Laminge · 24-09-2005, 09:31 AM

Its a community service that strengthens thighs and lightens wallets...

**Falcon Coupe** · 24-09-2005, 09:40 AM

The weight of the car has nothing to do with stall speeds or flash, a heavier car will require a higher stall speed to get off the line but that should be taken into account when ordering the convertor.

Casper · 24-09-2005, 10:26 AM

Quote:

Originally Posted by Falcon Coupe

The weight of the car has nothing to do with stall speeds or flash, a heavier car will require a higher stall speed to get off the line but that should be taken into account when ordering the convertor.

exactly.. although flash speed MAY be effected.. but we are talking extremes and only minimal difference

gozza · 24-09-2005, 11:13 AM

wtf is a flash speed

xr8ute · 24-09-2005, 11:33 AM

Quote:

Originally Posted by gozza

wtf is a flash speed

Have a read of this, http://www.converter.cc/tech.htm

gozza · 24-09-2005, 11:34 AM

thanyou kind sir

gozza · 24-09-2005, 11:38 AM

ahh i dont really understand any of that
so flash is basically when u plant it and u get more stall for a breif period than ur supposed too???

**Falcon Coupe** · 24-09-2005, 12:16 PM

Thats about it Gozza, i have just put a 5000rpm covertor in mine, i may have to flash if my brakes can't hold it on stall.

xr8ute · 24-09-2005, 12:31 PM

Yep, pretty much. What I found interesting at the start of that doco was the relationship it made between torque multiplication and converter efficiency.

**Stav** · 24-09-2005, 01:01 PM

Quote:

Originally Posted by Falcon Coupe

The weight of the car has nothing to do with stall speeds or flash, a heavier car will require a higher stall speed to get off the line but that should be taken into account when ordering the convertor.

Ok I am no authority on this subject but have a read under stall speed,

http://www.tciauto.com/tech_info/tor..._explained.htm

brenx · 24-09-2005, 06:39 PM

Short story is a 3000rpm stall under the foot brake may only be 2400-2500rpm for example. Flashing it may achieve 3000-3200rpm. Transbrake is the only reliable way of getting maximum stall reliably but it'll be a lower rpm figure than flashing it.

I've played quite a lot with different rpm stalls over the last 5 years. Enough to know what makes a good or bad stall. One thats loose isn't a good stall. You still want good part throttle response which I think Casper has stated in different wording?

One thing to remember is not all engines will respond the same way with a highstall especially if it's down on torque.

How's JMM rate the 3000rpm stall? Is it flash speed or foot brake speed?

**Stav** · 25-09-2005, 06:52 AM

Casper what do you think 0-100 is like now ? Do you think it has made a good difference? Can you take a stab in the dark mate?

Casper · 25-09-2005, 10:44 AM

Quote:

Originally Posted by brenx

Short story is a 3000rpm stall under the foot brake may only be 2400-2500rpm for example. Flashing it may achieve 3000-3200rpm. Transbrake is the only reliable way of getting maximum stall reliably but it'll be a lower rpm figure than flashing it.

That about sums it up perfectly.

Quote:

Originally Posted by brenx

I've played quite a lot with different rpm stalls over the last 5 years. Enough to know what makes a good or bad stall. One thats loose isn't a good stall. You still want good part throttle response which I think Casper has stated in different wording?

Part throttle response on the JMM one is very good, better then I expected to be honest. There is always some compromise with a higher stall (and this one is no different) however I think the compromise is easily less then I expected and cartainly within levels that anyone here would accept. Overall, its been a great mod.

Quote:

Originally Posted by brenx

One thing to remember is not all engines will respond the same way with a highstall especially if it's down on torque.

Precisely. I think I'm actually lucky with the VCT having the ability to advance the cam, allowing for decent low down torque while still getting a nice advanced power curve at high revs. This stall seems to be made for this car

Quote:

Originally Posted by brenx

How's JMM rate the 3000rpm stall? Is it flash speed or foot brake speed?

Its based on foot brake BUT you need a lot of power to get 3000rpm stalled. I have around 135-140rwkw and I get about 2700rpm on brake stall. I would say 170rwkw would see close to the full 3000rpm. As for flash, I've seen it hit over 3100rpm flashing so a real 3300rpm flash speed is probably possible.

Quote:

Originally Posted by useless

Casper what do you think 0-100 is like now ? Do you think it has made a good difference? Can you take a stab in the dark mate?

Not a clue. It will be significantly faster though. Not going to speculate how much faster.

Casper · 25-09-2005, 04:21 PM

Just for the record, Mrs Casper took the XR today to softball. She was just driving on 60 and 70 zone roads and taking it easy. From all accounts she simply didnt notice any difference in the car. I think that speaks volumes for this histall.

sfr rob · 25-09-2005, 04:31 PM

so...... say when your at the lights and take off the car moves as soon as you have your foot on the gas yeah? what about when you take your foot off the brake.. .does it creep forward or stay still?

or does it take till you hit 3000rpm to move?!?!?!

so confusing! but sounds, oh so good!

Casper · 25-09-2005, 04:38 PM

Quote:

Originally Posted by sfr rob

so...... say when your at the lights and take off the car moves as soon as you have your foot on the gas yeah? what about when you take your foot off the brake.. .does it creep forward or stay still?

or does it take till you hit 3000rpm to move?!?!?!

so confusing! but sounds, oh so good!

If your just taking off normally it behaves EXACTLY like yours does at the moment except instead of sitting at about 1800rpm as you move off it will go to about 2000rpm instead.

sfr rob · 25-09-2005, 05:01 PM

oh...

i bet your having WAAYYY to much fun with it!

Casper · 25-09-2005, 05:03 PM

Quote:

Originally Posted by sfr rob

oh...

i bet your having WAAYYY to much fun with it!

Actually, I havent really had much of a chance to drive it apart from a bit of a freeway run yesterday. It was fine on the freeway, couldnt really notice it much.

crakrz · 26-09-2005, 09:02 AM

Casper, it would be interesting to see how your fuel economy figures have changed since the stall. However I do realise that with the new found personality of your car it maybe a while before "fun factor" settles down a bit and you start driving normally again. Although I realise this make take some time with the steroid injection your ride is currently enjoying.

Casper · 26-09-2005, 09:14 AM

Quote:

Originally Posted by crakrz

Casper, it would be interesting to see how your fuel economy figures have changed since the stall. However I do realise that with the new found personality of your car it maybe a while before "fun factor" settles down a bit and you start driving normally again. Although I realise this make take some time with the steroid injection your ride is currently enjoying.

Mate, I havent gotten much better than 400kms out of a full tank since the exhaust went on over a year ago. I justt never drive in a 'economy' style. If I wanted economy I would have bought a Camry

Seriously, I drive my car to enjoy it. It is lucky to do 6000kms a year these days so fuel prices etc are not hurting me as much as many others. Thats why I dont have any issues about killing off whats left of any resemblence to fuel economy now.

As for how much the stall has changed it, I would hazard a guess at the moment and say it has reduced economy by between 7-10% from what it was. I will be happy with 370-390kms a tank now.

LG · 26-09-2005, 04:51 PM

If your having traction problems with the stall, with IRS, what hope have we got. Will it do more harm then good? Sounds more like a burnout tool than anything.

Casper · 26-09-2005, 04:56 PM

Quote:

Originally Posted by LG

If your having traction problems with the stall, with IRS, what hope have we got. Will it do more harm then good? Sounds more like a burnout tool than anything.

Its not too bad now. Yes, I can light them up from standstill at will but you get used to it quickly and modify your takeoffs to suit. I can pretty much launch it now with minimal if any wheelspin. At the drags it will hook up with ease. 16" tyres, 20psi, instant grip and go. Admittedly the IRS certainly helps but it would still be ok on a live axle, you just have to learn the 'feel' of it again.

Forget the wet.. any idea of booting it off the line and its burnout city... but you live axle drivers would be used to that anyhow :P

LG · 26-09-2005, 05:00 PM

Cheers, gotta start saving a bit. Sounds like it's a great mod. I've already got a cooler, so i suppose it'd be a bit under $1k for it.

Casper · 26-09-2005, 05:10 PM

Quote:

Originally Posted by LG

Cheers, gotta start saving a bit. Sounds like it's a great mod. I've already got a cooler, so i suppose it'd be a bit under $1k for it.

Yeah, without a cooler about $1K fitted I guess, bit less amybe.
Get your headers first though so you can rev free'r and then youll REALLY notice the difference. mid 15's or less would be a shoue in with your car, maybe low 15's.

Casper · 28-09-2005, 07:13 PM

Moved to where it belongs

Casper · 29-09-2005, 10:55 PM

Well, Sprint_ED and I took it out for a test tonight. 3100rpm on the brake... not bad!
Tried it a second time, within about 100meters, 3100rpm again.. and overcooked it (yes Brenden, I know, I broke the rule) and limp home. Puttered along and it all worked fine again within 30 seconds.

Best launch is stall to 2100 quickly then flash it to about 3200rpm as you step off the brake, it fairly thrust us back into our seats...2 people in the car and a full load of fuel regardless.

If anyone doubts that it has made a rather dramatic difference to how the car launch's please feel free to ask Sprint_ED, I'm sure he can let you know what he thought of it!