550hp and 30mpg First Goal

[bazman]

Car is an Australian Holden Commodore SS. Model is a VT series 2 with the LS1 5.7 V8 and the 4160e auto through a 3.07:1 rear end. Car weighs aprox 3750lbs (not weighed it but based on specs). They are like a 4 door GTO.

It has averaged 18.75mpg over the last 50,000 miles combined city and highway. (We work in metric or imperial down under but all figures I quote will be converted to US to ensure comparability).

Well, I've achieved the first goal (550hp) thanks to a low boost turbo set up at the back (STS custom setup). Now I'm working on the 2nd part (30mpg at cruise). That bit seems a tad harder.

Best so far of 25.8mpg under pretty much ideal cruise conditions and it is as lean as it will run without stumbling on itself - so no more tuning is going to help (about 20 hours on dyno just doing drivability etc so I'm not exaggerating).

Before I changed the cam the car could get 27.5mpg on a long trip. The cam has cost me about 15% in lost mpg overall but the extra 50rwhp is not coming off anytime soon as I like it too much, so I have to get creative now.

Here are my thoughts to get it done:

1 - Fit Rhoads variable duration roller lifters. This will bleed off (depending on how much adjustment we give it) from 5 - 15 degrees of cam duration at low rpms. This will lift vacuum and make the cam behave like a stock one - lifting mpg and power at low revs we hope. As the rpms climb the cam will retain its current specs so this mod should retain top end while improving the bottom end.

The down side will be a requirement to run adjustable roller rockers and hence noise and lash adjustment checks every oil change - but I can live with that.

The lower duration at low rpms should enable us to run less idle and maybe a little leaner.

I'm hoping this alone will get me back to 27.5mpg at cruise (av 62mph or 100kph). That would be 33mpg imperial.

2 - Fit a Plasma ignition system - the Blue Phoenix unit tested by David Vizard. The bigger spark is worth a few extra hp I likely won't notice, but what it will do is greatly enhance our ability to run leaner - we should now be able to get into the 20's A/F without power loss at cruise....

3 - Fit another water/meth injection system (the one I have only comes on under boost and is not mappable). They can share tanks but I'm thinking of using a modern ultra accurate EFI feul injector and adapting any old ECU to run it then inject water/meth under lean burn conditions.

e.g. the GM computer we have set to bring in lean burn after a few seconds of steady light throttle cruise, if we could pick up the signal when it is triggered we could simply tell the water ecu to follow suit and start injecting.

We could run water/meth all the time in direct proportion to gas (about 20% by volume) but we'd then need to refill the 15L tank every tank of gas - and that'd get tricky seeing as methanol is not exactly at most service stations. Yes we could run 100% water, but at 10.5:1 compression with boost, I'd rather have the added insurance of 50% meth.

I'm hoping the plasma and water/meth will get me past 30mpg by allowing a much leaner mix than the engine can now tolerate while maintaining adequate power to hold cruise speeds.

A later project will involve a new built engine and then we'll go for 40mpg and 600rwhp, but I need to walk before I can run.

I believe we can have our cake and eat it too - we do not need small engines to get acceptable mileage. I know of a 500 cubic inch twin turbo Viper that makes over 1000hp (at crank) and can get 30mpg under steady cruise. That is no longer technically difficult. Getting to average 35mpg IS difficult.

Welcome anyones thoughts

[JanGeo]

Work on reducing friction first, I took my BMW from 35-38 MPG up to 60 MPG with leaning the carb main needle on the BING carbs and Teflon impregnating the transmission parts only with top speed in top gear at engine redline without full throttle.

[bobc455]

I think Rhoades are a great way to go - especially with tall gears. I went from about 14-15MPG to 17-18 MPG by putting in the Rhoades. And I picked up about 1/2 second in the 1/4 mile because the engine made so much more low-end torque (which really helps with tall gears).

The 4L60-E is a good way to go, especially since you have a lockup. With my Turbo-400, I am stuck with no lockup. The best I can do is a switch-pitch converter, but the lockup & OD is a great way combination. I bet the lockup alone is worth 2-3 MPG for you.

Since you have a turbo, can you go with a smaller cam and crank up the boost to get your 550HP?

Over the years I have become less and less impressed with ignition mods. I don't know the "plasma" system, but I've been running an MSD for a long time and frankly I consider it to be extra hardware. Instead, I'd rather go the hottest plug you can find (which could be tricky with a turbo), and focus on the correct gap and timing. There is also the possibility to index the plugs but I've heard mixed results about that.

Aerodynamics are the next thing. Can you smooth it out?

What about running the engine hotter?

-Bob C.

[pgfpro]

Love your project!!!

I'm going for the same type of deal. Performance and decent fuel mileage.
My new goals are now a 9 second 1/4 mile ET and 45mpg.

I also tried the water injection during lean burn and it didn't help at all. If anything it loss fuel mileage. It reduced the flame speed and I had to add more timing, in which I was already running to much in my application IMO.

My HP cams also reduced fuel mileage at light to medium loads(city driving) but had no effects at freeway with steady state driving. So what I did was started running John Deer Hygard hydraulic fluid in my auto. This improved the city driving mileage. The down side is it lowered my stall speed 500rpm less on my other single turbo system. So now I'm running a compound turbo system with a smaller primary turbo then before. My secondary turbo or atm turbo is a BW 75mm that flow 95+ lbs/min.

I like your lifter idea and can't wait to see how it works for ya.

Good luck on your project and keep us informed.

[bazman]

Originally Posted by JanGeo

Work on reducing friction first, I took my BMW from 35-38 MPG up to 60 MPG with leaning the carb main needle on the BING carbs and Teflon impregnating the transmission parts only with top speed in top gear at engine redline without full throttle.

You mean something like this?

http://www.nanolube.net/

It sounds great, but at $800 I'd really want to be impressed.

I have used Militec http://www.militec-1.com/ and I believe it contributed to greatly reduced wear though have no proof other than a great condition engine after 110,000 miles. It does stain your entire engine diarrhea brown though

[bazman]

Originally Posted by bobc455

I think Rhoades are a great way to go - especially with tall gears. I went from about 14-15MPG to 17-18 MPG by putting in the Rhoades. And I picked up about 1/2 second in the 1/4 mile because the engine made so much more low-end torque (which really helps with tall gears).

The 4L60-E is a good way to go, especially since you have a lockup. With my Turbo-400, I am stuck with no lockup. The best I can do is a switch-pitch converter, but the lockup & OD is a great way combination. I bet the lockup alone is worth 2-3 MPG for you.

Since you have a turbo, can you go with a smaller cam and crank up the boost to get your 550HP?

Over the years I have become less and less impressed with ignition mods. I don't know the "plasma" system, but I've been running an MSD for a long time and frankly I consider it to be extra hardware. Instead, I'd rather go the hottest plug you can find (which could be tricky with a turbo), and focus on the correct gap and timing. There is also the possibility to index the plugs but I've heard mixed results about that.

Aerodynamics are the next thing. Can you smooth it out?

What about running the engine hotter?

-Bob C.

Good news re your Rhoads experience.

re the cam and more boost - yes it would work but my engine is not built to take the increased boost so I'd risk being counter-productive.... as in throwing a leg out of bed or the good ol LS1 pooping its pants.

My goal is not just mpg but to get a large performance engine to get good mpg - the difference helps justify large engines because there are some that would have them banned. I never want to see large engines banned so want to play my part to simply make them greener so we can all enjoy them into the fore-seeable future

re ignition - agree with you. The reason for Plasma is simply that normal ignition can only fire so lean and I am at that limit now at cruise. Plasma allegedly can push those A/F ratio limits higher. We'll see.

Aero - maybe a front cover under the front. It is a good idea.

Heat? It works, but it also kills boosted engines. I'd be inclined to heat the fuel on a by-pass so that I could switch from hot fuel to cold fuel instantly based on demand.... i.e lean cruise runs on hot fuel, throttle opening pulls in cold fuel. Hot fuel does wonderful things for emissions too so I am keen on that.

[bazman]

Originally Posted by pgfpro

Love your project!!!

I'm going for the same type of deal. Performance and decent fuel mileage.
My new goals are now a 9 second 1/4 mile ET and 45mpg.

I also tried the water injection during lean burn and it didn't help at all. If anything it loss fuel mileage. It reduced the flame speed and I had to add more timing, in which I was already running to much in my application IMO.

My HP cams also reduced fuel mileage at light to medium loads(city driving) but had no effects at freeway with steady state driving. So what I did was started running John Deer Hygard hydraulic fluid in my auto. This improved the city driving mileage. The down side is it lowered my stall speed 500rpm less on my other single turbo system. So now I'm running a compound turbo system with a smaller primary turbo then before. My secondary turbo or atm turbo is a BW 75mm that flow 95+ lbs/min.

I like your lifter idea and can't wait to see how it works for ya.

Good luck on your project and keep us informed.

Whoa - dude - you are the man! Anyone that can get any car to those kind of figures has my utmost respect. Doing it with an AWD Talon is a great achievement! Do you have AWD full time or do you run RWD at cruise?

re water - I have heard others say the same thing so am cautious about going there. I'm going to rely on the plasma ignition to get my A/F at cruise into the 20's. If the burn is efficient the engine should not require water injection for cooling, so I agree it should not be needed.

At that point I just want to see if a 50/50 mix of water/meth will aid combustion and allow a little more leaning out. The water may not help, but the meth might - it's worth a try unless you've already done the water/meth at cruise too???

Your John Deer Hygard hydraulic fluid idea has me intrigued.... does the trans run cooler with that? That alone may be worth it. The 4160e is not designed for 450rwhp The tighter stall would also help economy and driveability - at the expense of hitting the power in the sweet spot could be worth trying I can always go back to the normal fluid if I don't like it

thanks.

What do you attribute the biggest contributors to getting over 40mpg from your very fast machine?

[JanGeo]

Originally Posted by bazman

You mean something like this?

http://www.nanolube.net/

It sounds great, but at $800 I'd really want to be impressed.

I have used Militec http://www.militec-1.com/ and I believe it contributed to greatly reduced wear though have no proof other than a great condition engine after 110,000 miles. It does stain your entire engine diarrhea brown though

No the Teflon impregnation is a heated high pressure gas treatment where the Teflon gas actually penetrates into the metal pores and makes the surfaces extremely slippery. A piston wrist pin will fall out of your fingers if held sideways, it happened to me with one of my brothers pins, I couldn't believe it. I did my entire transmission, drive shaft ends and rear hub on my 1978 R100s BMW and what a difference it made! Cost was about $195. I did not do anything to the engine other than some slick 50 oil treatment. The rear hub also runs much cooler and spins more than a revolution around when spun by hand. All seal surfaces were also treated causing less seal drag.
Another easier way to achieve similar results may be to use Synlube which is a colloidal mix of Teflon ptfe, graphite and Moly in a non petroleum base liquid which I use in my Scion xB since my first oil change at 3800 miles, now at 48,000 miles.

[pgfpro]

Originally Posted by bazman

Whoa - dude - you are the man! Anyone that can get any car to those kind of figures has my utmost respect. Doing it with an AWD Talon is a great achievement! Do you have AWD full time or do you run RWD at cruise?

re water - I have heard others say the same thing so am cautious about going there. I'm going to rely on the plasma ignition to get my A/F at cruise into the 20's. If the burn is efficient the engine should not require water injection for cooling, so I agree it should not be needed.

At that point I just want to see if a 50/50 mix of water/meth will aid combustion and allow a little more leaning out. The water may not help, but the meth might - it's worth a try unless you've already done the water/meth at cruise too???

Your John Deer Hygard hydraulic fluid idea has me intrigued.... does the trans run cooler with that? That alone may be worth it. The 4160e is not designed for 450rwhp The tighter stall would also help economy and driveability - at the expense of hitting the power in the sweet spot could be worth trying I can always go back to the normal fluid if I don't like it

thanks.

What do you attribute the biggest contributors to getting over 40mpg from your very fast machine?

My Talon is Full Time AWD.

I tested the H2o/Meth injection at light load cruise speeds also and it didn't help in my situation. But its also something I didn't spend a whole lot of time on.

Sorry I didn't test my transmission temps running Hygard with and without. On the yellowbullet forum several very high power V8's are seeing a much lower temp when running Hygard. You will definitely see your converter tighten up though. Plus your cluch packs will love ya for running it.

My trans mods:
Transtar/IPT 5 disk front clutch kit in stock basket.
Transtar/IPT end clutches
double up stock flexplate
John Deere HyGard fluid
Foreign Muscle DSM (Transmission Control Unit) EPROM Upgrade with adjustable line pressure


My biggest contributor to an increase in mileage would have to be my (lean-burn pre-chamber). Its something I have been developing for the last 15 years. I have tested it on two different Hondas and now on my Talon. I should be done with the final version in about two more years.

[bazman]

Thought I'd throw in a pic or 2