Somender singhs groove theory tried.

[MikeHardy]

yeah those wedge head V8's have the plug going in from the side into that deep section.

[Les, slight limp]

Fetched the scrap 530 from suterman today, as soon as it's chopped i'll get the pics up.

[745 TurboGreasel]

Originally Posted by ravennexus

what you mean like the 531's (which help the intake flow more)

Concensus it it may help with low octane fuel in a truck, but for any perfomance use it should be ground off.

[PRVersion]

jonny and i've been talking about this lately for the b20...i was under the "bollocks" impression, but at the same time i'm fascinated...i cant wait to see how it comes out!

[MikeHardy]

the fin in the 531 is to direct flow around the valve stem. porters usually just sharpen it.

[linuxman51]

Originally Posted by 745 TurboGreasel

Concensus it it may help with low octane fuel in a truck, but for any perfomance use it should be ground off.

dayum gangsta, what consensus was that?

[Les, slight limp]

Another couple of observations, cruising 50-60 mph the engine feels much smoother ie less harsh, not a critique of volvo's but a fact of life with large 4 bangers, on the downside the engine seems to take twice as long to get to operating temps, i push the choke fully in when the mickey mouse temp gauge gets to middle, it seems that the engine needs the oil to be up to operating temps to run correctly, i don't trust the temp gauge though, seems more of an idiot light than a real gauge.

[Janspeed]

Originally Posted by Les, slight limp

on the downside the engine seems to take twice as long to get to operating temps, i push the choke fully in when the mickey mouse temp gauge gets to middle, it seems that the engine needs the oil to be up to operating temps to run correctly, i don't trust the temp gauge though, seems more of an idiot light than a real gauge.

That's a good sign. less energy loss! (less dissipation of heat in coolant/head) More energy converted into torque. In other words more efficient! Stuff in a hotter thermostaat to compensate and bring up the temp in the head!

[MikeHardy]

you got an 87 or 93C stat in that les. seems like i might need to do this sooner then planned.

[mikep]

Originally Posted by Janspeed

That's a good sign. less energy loss! (less dissipation of heat in coolant/head)

It seems the other way to me. Power is the thing we want, heat is the byproduct. More efficient burn= more heat byproduct.

[Les, slight limp]

I don't think it needs a hotter stat, as when it's warmed up, approx 4-5 miles it drives fine, i'm just trying to tell it like it is, i know one of the claims made for this is lower combustion temps, i had trouble with that one as i would have thought that a more complete burn of the fuel would have raised temps, any thermodynamics students/experts out there can probably explain why it burns cooler or whatever, if it does burn cooler would that affect turbo performance.

Ok theory time, feel free to shoot holes in it coz that's what theories are for.

Sorry, i got half way through typing it and realised that it would actually raise engine temps lol.

Edit: About the stat, i don't know, tell me what to look for and i'll go look.

[MikeHardy]

you'd have to pull it out to see. volvo orginal are 87 or 93, aftermarket are often 88 or 93.

the question is does the more complete burn put more heat out of the exhaust pipe in gas temps instead of leaving fuel lingering around the edges and rings to burn slowly and put heat into the engine.

[Janspeed]

I guess a stat that opens later: 93C

about the theory, I'm following the line of reasoning of Singh here. I'm no thermodynamics engineer but I think that when a charge has burnt completly in a shorter time it has more time to exert pressure on the piston and less time to exchange heat/energy with the head since the burningproces itself has taken shorter.

sidenote: We all know that diesels are more efficient when it comes to converting fuel to propulsion. Here in Europe many cars use highly efficient commonrail direct injected turbo-diesels. These engines are so very efficient that it is a real issue in winter temperatures, the heater only starts working after about 10 miles... many carmakers now also offer a auxilary 2nd car heater as well. Therefore: the more efficient the combustion, the cooler the coolanttemp.

[BDKR]

I got anoter 530 in yesterday but I'm still trying to get my car running again after the tranny swap. Foo bar'ed or forgot something.

[BDKR]

Les: Have you changed your oil since this? Another thing that's reported by everybody doing this is that the oil stays clean. Or at least it stays cleaner for longer. LOL

Anyway, it appears that some of that unspent charge also makes it's way past the rings and into the oil supply.

[acbarnett]

Originally Posted by Janspeed

I guess a stat that opens later: 93C

about the theory, I'm following the line of reasoning of Singh here. I'm no thermodynamics engineer but I think that when a charge has burnt completly in a shorter time it has more time to exert pressure on the piston and less time to exchange heat/energy with the head since the burningproces itself has taken shorter.

sidenote: We all know that diesels are more efficient when it comes to converting fuel to propulsion. Here in Europe many cars use highly efficient commonrail direct injected turbo-diesels. These engines are so very efficient that it is a real issue in winter temperatures, the heater only starts working after about 10 miles... many carmakers now also offer a auxilary 2nd car heater as well. Therefore: the more efficient the combustion, the cooler the coolanttemp.

at the opposite end of the spectrum are turbines, think of how hot they get and how much fuel they go through to make a given amount of power...

[JW240]

very cool! i have been thinking about this too. time to find a small old engine!

With a cnc machine or normall mill, you could get some pretty wicked grooves in the quench area's of the head!

edit:

Originally Posted by acbarnett

at the opposite end of the spectrum are turbines, think of how hot they get and how much fuel they go through to make a given amount of power...

true, the higher the temp, the more efficient....

[acbarnett]

in terms of fuel efficiency, turbines are at the far opposite side of diesels, they make alot of power for their weight but you pay dearly in fuel consumption...

[InferiorWang]

Originally Posted by Janspeed

I guess a stat that opens later: 93C

about the theory, I'm following the line of reasoning of Singh here. I'm no thermodynamics engineer but I think that when a charge has burnt completly in a shorter time it has more time to exert pressure on the piston and less time to exchange heat/energy with the head since the burningproces itself has taken shorter.

Also not nearly an expert in thermodynamics, but I thinks that's kind of right. Since the burn is shorter and optimum pressure can be achieved during a shorter time, then ignition timing can be advanced, so there is then less time for heat transfer after ignition.

Sound good? There's probably more to it. Thermodynamics is never simple.

[Les, slight limp]

In ye olden days ie 70s, to time a car you'd turn the dizzy until the idle was at it's fastest and then retard 5 degrees, i'll try that tomorrow and see what it gives, while i'm at it i'll try it to 30 degrees static advance and see if i can induce light knock.

[linuxman51]

Originally Posted by mikep

It seems the other way to me. Power is the thing we want, heat is the byproduct. More efficient burn= more heat byproduct.

true but not nesc. transfered into the cooling system.

[Les, slight limp]

I am not due an oil change, i only do about 5500 miles a year and change every 6 months.

I got the head chopped tonight, even with that deep groove i did there's still 4-5 mm of metal left at the thinnest point, pics tomorrow.

Will check the stat tomorrow as well, sorry i can't do any tonight, my busted bits are complaining.

[745 TurboGreasel]

Originally Posted by Janspeed

I

sidenote: We all know that diesels are more efficient when it comes to converting fuel to propulsion. Here in Europe many cars use highly efficient commonrail direct injected turbo-diesels. These engines are so very efficient that it is a real issue in winter temperatures, the heater only starts working after about 10 miles... many carmakers now also offer a auxilary 2nd car heater as well. Therefore: the more efficient the combustion, the cooler the coolanttemp.

Diesel engines also are made with a good bit more mass to deal with the stress of uncontroled combustion. Generaly the coolant capacity is at least 30% larger than a gas motor of similar displacement. Both of thse contribute to longer warmup times.

[Janspeed]

In the warmup fase the engine and coolant are cold, if a diesel was producing so much waste energy the head would heat up very fast after starting the engine from cold > the thermostat would open fast too > the heat would start circulating through the cooling system relatively fast too. > heater would be giving of heat in the interior fast to.

But wait, it doesn't!
the heater stays cold for a considerably longer time then in a petrol/LPG-engined car. I've driven many Diesel cars, I just know from experience.
Once warmed up the Diesel with it's heavy block needs a bigger cooling system but before it's warm enough to need that cooling capacity a long time has passed driving the car. It really takes a long time to get a Diesel at optimal operating temperature.

[740Weapon]

so...

if you (les) are a scientifical type person and not a placebo type person.

how about some MPG figures.

warming up taking longer could mean a drop in efficiency... combustion not getting as hot.

im with mike P.

more heat=more efficiency.

this whole diesel thing:

diesels are efficent because of their high compression and that they USE That high compression... diesels have no throttle plates.

the throttling process of a gasoline engine makes the effective compression pretty darn weak under most driving conditions.