86TpiTransAm

Originally posted by Scrams84Z in another post: "These engines don't really wake up until 180*-185*."

Originally posted by MikeInAZ: "No disrespect 86TPI but I think Scram is right. They wake up about 180/185 because they are approaching normal operating temp 194°"

I was recently in a discussion about this with Ed Wright, who most of you probably know from his reputation with chip burning. After he told me that our engines make max power at 130-140 degrees I told him about what you all have said. This is his response to that and I'd have to say I agree with him....

"I can tell you whoever on the "message board" posted that has never dyno tested one at different temps to find out. Do you think myself, the engineers at Hypertech, JET, ADS, are all too damn dumb to test something like that? With most TPI cars there is an easy 4 to 6 rwhp between 140 and 190 degrees. Only aluminium engines make more power above 180. I have never seen an iron block Chevy make more power at higher temps. The LS1s do, but they all have aluminium heads and blocks. I built and tuned real race engines for almost 30 years, I don't make this stuff up. If you ever go to the NHRA drag races, see how long the Pro Stock guys warm their engines. They start the burnout dead cold. They try to leave the starting line @ 135/140 degrees. Depending on the weather, they hit the finish line about 160/170 degrees. Iron blocks and aluminium heads on those. The only way one would make more power that hot would be if they were trying to tune it to 800-something mvs by the stock O2 sensor, and actually had it too lean.
Tune the fuel for max power at any temp you want to pick, and it will still make more power cooler. If somebody wants to bet a couple hundred on it, bring a car. I have the dyno.
The internet is running over with "experts" that only sit on their butts and decide things are a certain way. You should ignore about 90% of what you see there."

Mark A Shields

That makes perfect sense to me what Ed said. The only thing is, with our motors they were designed to run warm for emissions so going to a 160* with a computer might cause problems, but if you can by pass that, then yeah 160* stat would be great. That's what I run in the summer time.

cp87GTA

I live in central IL., and run a 160 stat. Summer and winter, it takes me a couple of miles to go into closed loop. I live outside of town, about 3 miles to the first stop light. Allways in closed loop by the time I get there. My car has never overheated, since I've had it. Although I have adjusted for it in the prom. I also believe there is more power, running below 180 on a iron headed engine.

86TpiTransAm

Yeah, that's the way I see it too. Emissions would be the only reason to run a hotter thermostat than 160 degrees unless it's winter time and then I could understand switching to a hotter one for the heater.

zippy

there is a bit more to it that ed didn't point out. the engine temp on a dyno for a tpi engine will produce best power around 172 which there isn't a thermostat for. the 170 won't do it since you have to stop, do a burnout, and then go up to the line to wait for the lights which would raise the temp above it. for highway running the 170 would be great. what the big boy's do by starting them up cold is to avoid them from overheating. it's not for power. you won't find cooling systems on most and if you find any cooling systems on certain class vehicles it's only enough to keep them cool at idle for the mostpart. there are some people out there that actually have been involved in engine temperature dyno testing other than ed wright. i also feel this topic is being getting no where and is pointless with the lack of experienced people on here.

86TpiTransAm

Ed said that the engine temp on a dyno for a tpi engine will produce best power around 130-140 degrees. I'll take HIS word for it since you yourself happened to point out the "lack of experienced people on here."

And as Ed pointed out.... "If somebody wants to bet a couple hundred on it, bring a car. I have the dyno."

MikeInAZ

You're not comparing apples to apples, nor is Ed. The original poster, Larry Dunlap, asked if a 160 stat was too low for his stock 305 TPI and what would the adverse effects be. He didn't mention horsepower at all.

Following Ed's train of thought then I suppose GM, the people that designed the engine in the first place are too dumb to figure things out and we should listen to people that design their "theory" around dyno's and desktop PC software, rather than the real world. I can't even count the number of people that wasted their money on one of these "superchips" only to mess with it, tinker, tamper and tune only to yank the thing out and go back to the stock chip or wind up burning their own.

Of course an engine on a dyno or anywhere else is going to produce more horsepower at a cooler temp. So what? Take that to the track and you will get more horsepower and less consistency and chances are you'll be looking at tail lights.

Consistency wins. Talented drivers win. Horsepower is only one equation of a successful "package".

Personally I never heard of Ed, and don't have any reason to doubt him but many of the "people on this message board" are just offering their experiences not trying to be armchair shadetree mechanics.

If he would be interested in where some of us get these confounded dumb ideas I got many from my Dad 35 years ago. Here are his credentials.



NHRA World Record Holder L/SA May 1969

BTW...... dad didn't have a dyno either does Ed have one of these?

86TpiTransAm

You're absolutely right, the original post didn't say anything about power. I wasn't posting this topic in response to the "original" post either. i was posting this topic in reponse to the "these engines don't really wake up..." post. When in fact these engines make more power when colder.

BTW... how many fuel injection setups were available in 1969??

Technology wasn't quite as advanced in 1969 as it is today and there wasn't such a broad amount of options available like there is today.

:lala:

zippy

the number of advantages of an engine that cold are lower than that of a slightly warmer engine. i'd be willing to bet with him, having the time to get there to go over the bet would be a different story as well as having the engine dyno'd with certain terms. if this information came from lingenfelter i'd say the testing i've been involved with and researched just was done incorrectly. ed wright is no john lingenfelter although i will say he does a good job with programming.

86TpiTransAm

You're right, Ed isn't John Lingenfelter. But just because John Lingenfelter builds engines and makes cams and stuff like that doesn't make him any better than Ed. Now YOU are comparing apples and oranges. Ed programs, John builds engines and other items. There are some things that I don't agree with that John does and I'm sure I'm not the only one. Ed has been building and racing engines for over 35 years, just because he doesn't build them FOR people and doesn't sell his engines doesn't make him any less knowledgable than John Lingenfelter.

MikeInAZ

Not disputing that a colder temp produces more power. As a matter of fact that is pretty basic physics. A lower temp produces more air density, and further it causes most fuel systems to "enrich" themselves.

However, the comment "doesn't wake up" was in referring to a stock 305 TPI with a stock chip. And I stand by the statement that Scram made. Why? Because every calibration in these "stock" engines was made at 194° @ 1000 RPM which has been deemed Normal Operating Temp.

To say that these engines produce more horsepower at 130 to 140° is like saying you were only one number away from winning the powerball. It's pointless. Why?

Because these engines are not going to run at that temp..... stock. We were, I thought, talking about every day use, every day driving, every day engines.

You could also gain a fraction of horsepower by increasing the airflow by removing your air cleaner. But do you run your car without one?

And for one moment let's say you could keep your temp at 130 to 140 on a stock tpi with the stock chip. Then, courtesy of Vader, go through this checklist and mark off every ECM based decision that is not going to operate properly and you will see why operating at normal operating temp, the majority of the time, will "wake" your engine up.

Coolant Temperature Sensor Related Parameters
BLM enabled between 50°C (122°F) and 140°C (284°F)
Cold spark advance disabled above 56°C (133°F)
Hot spark retard begins above 116°C (240°F)
Highway Mode spark advance > 59.8°C (140°F)
Knock sensor disabled below 66.5°C (152°F)
Power enrichment at base A/F ratios > 56°C (133°F)
Target IAC idle RPM >80°C (176°F)
IAC multiplier at 1.0 (base) > 32°C (90°F)
Knock Control enabled > 67°C (153°F)
EGR Duty-cycle enabled at 56°C (133°F)
EGR Duty-cycle at MAX >80°C (176°F)
TCC lockup enabled >50°C (122°F)
SHIFT light enabled >50°C (122°F)
Diagnostic communication enabled at 70°C (157°F)
DTC 43 enabled > 90°C (194°F)
Cooling fan #1 enabled at 107°C (226°F)
Cooling fan #1 off at 104.7°C (220.5°F)
Cooling fan #2 enabled at 115.2°C (239.5°F)
Cooling fan #2 off at 110°C (230°F)
Cooling fan duty cycle at 100% at 80°C (176°F)
Acceleration enrichment multiplier at 1.00 below 80° C (176°F)
Acceleration enrichment multiplier at 0.75 above 80° C (176°F)
Acceleration enrichment multiplier at 0.50 above 104°C (220°F)
Acceleration enrichment decay factor at 25% below 80° C (176°F)
Acceleration enrichment decay factor at 40% above 80° C (176°F)
Acceleration enrichment decay factor at 50% above 104° C (220°F)
Acceleration enrichment decay factor at 60% above 128° C (262°F)
Fuel limiting factor timer at 217 counts below 80° C (176°F)
Fuel limiting factor timer at 169 counts above 80° C (176°F)
Code 13 (oxygen sensor fault) enabled above 70°C (157°F)
Code 14 (CTS high fault) enabled above 130°C (266°F)
Code 32 (EGR fault) enabled above 30.5°C (87°F)
EVAP canister purge enabled above 70.3°C (158.5°F)
Hot closed-loop timer enabled above 70.3°C (158.5°F)
Rich/Lean O2 offest at 16 counts between 20°C (68°F) and 92°C (197.5°F)
A/C clutch disabled above 150°C (302°F)

No technology wasn't quite as advanced in 1969, and "ain't" technology a wonderful thing? But I sure am puzzled as to why "back then" is referred to as the "muscle car era".

zippy

your very correct there mike although i do believe ed was referring to programming an engine to run that cool which would benifit from looser tolerances and a water pump that would turn easier do to running without a thermostat as it's primary benifits. the a.i.t. could easily be kept as low with either thermostat so the benifits are there for both. as for the open loop situation, it's often set up rather well for power numbers even before closed loop enters although you wouldn't want to drive it that way.