Dyno tune

**bontrager** · 02-21-11, 09:04 AM

I'm a newbie as far as corvettes are concerned so please excuse my ignorance. About 4 months ago I purchased a 2000 6 speed vert with 11,800 miles on it.

Since then, I have added a cold air induction system, dual cone, with a mass flow air sensor and smooth coupler. Next month a short sift kit will be added along with the Caggs 1st to 4th gear shift eliminator.

Will a dyno turn benefit me now or should I wait until other minor engine /exhaust mods are done/ Considering adding a magnaflow x pipe to the stock system and maybe a new 160 thermostat ( Not sure I need this).

Any help will be appreciated.

**TooFast** · 02-21-11, 12:36 PM

You might get some benefit after you put in the X pipe and Cat back. I would do some research on the 160 thermo though. I have seen much discussion on not changing to the 160 thermo. The LS1 needs to run at a higher temp or cylinder wall damage can occur.

**Toms01** · 02-21-11, 12:46 PM

I don't know how much a dyno tune costs, and I know that is the best way to do it, but, East Coast Supercharging does mail order tunes that everybody raves about, and the cost is only $149.

You tell them what you have done and they will make the adjustments and send it back to you.

I may do this yet, this spring.

**bontrager** · 02-21-11, 06:18 PM

thanx to both of you. I won't change the thermostat and will call for more info regarding the dyno tune after exhaust update.

**warren s** · 02-21-11, 07:52 PM

You will be wasting your money if you get a tune with just a cold air intake and a cat back. A 160 t-stat will NOT harm your engine, but by itself its of little use.

You can call any shop that actually does tunes and ask them about the thermostat issue and the real world results of their tunes.

There are many variables involved, such as the climate you drive in, how you will be using the car, do you plan on other modifications soon and so on.

**bontrager** · 02-22-11, 01:17 PM

Originally Posted by warren s

You will be wasting your money if you get a tune with just a cold air intake and a cat back. A 160 t-stat will NOT harm your engine, but by itself its of little use.

You can call any shop that actually does tunes and ask them about the thermostat issue and the real world results of their tunes.

There are many variables involved, such as the climate you drive in, how you will be using the car, do you plan on other modifications soon and so on.

Thank you!

**TooFast** · 02-22-11, 01:32 PM

160 degree thermostat install

This link will take you to a thread I started last year. There is some very good discussion on 160 stats by c4c5specialist that I recommend you read. or just do a thread search on "160 degree thermostat install".

**SANOLS1** · 02-23-11, 09:08 AM

You might consider a dyno run before you start with any mods. It’s always nice to know your baseline so you can realize what improvements you’ve made in a real sense. I agree you probably don’t need a tune for the minor things you’ve mentioned, but as you start playing, eventually you will wind up going down that road.
Have fun along the way.

**Hib Halverson** · 02-23-11, 01:53 PM

There is little of any performance advantage to using a 160 thermostat vs. a 180. I dyno tested both of them and saw no practical difference. I'll add that other cooling mods tested at the same time were lower fan-on temps and a Fluidyne radiator. Without those mods, there's even less chance of seeing any gain because the cooling system, with a stock radiator and stock fan-on temps, is not capable of cooling that low to begin with.

In threads elsewhere on CAC, the durability issue has been discussed and, in addition to what's posted here, I've learned enough from other sources to conclude that running the engine that cool in the long-term may compromise durability, especially if one is used with other cooling mods such that sustained coolant temperature is below 170 degrees. The problem, as suggested by c4c5specialst elsewhere on the CAC, is piston skirt wear due to long term insufficient piston-to-bore clearance.

That engines loose pistons over long periods of time running at 160-165 degrees indicates that, even if the piston skirts don't fail, internal friction is higher and that extra friction will negate some or all of any of that "incremental" gain one might see.

"Warren S" has posted about a gain of two tenths on the drag strip with the lower temp 'stat, but that's not credible as he made two other changes at the same time and...if the car's a manual, it's really tough to properly test incremental gains because consistency is difficult.

It is true that, generally, spark timing is advanced is ECT decreases, but in practice the individual cal for the model year and powertrain in question may not have enough difference in the timing commanded for 165 and 186 to make a useful difference.

But...the increased friction and piston skirt durability are not a good tradeoff from the dubious performance "gains" a few suggest are possible.

Bottom line, put a Stant 180 in there and leave it at that.

**Remo** · 02-23-11, 04:05 PM

Originally Posted by Hib Halverson

There is little of any performance advantage to using a 160 thermostat vs. a 180. I dyno tested both of them and saw no practical difference. I'll add that other cooling mods tested at the same time were lower fan-on temps and a Fluidyne radiator. Without those mods, there's even less chance of seeing any gain because the cooling system, with a stock radiator and stock fan-on temps, is not capable of cooling that low to begin with.

In threads elsewhere on CAC, the durability issue has been discussed and, in addition to what's posted here, I've learned enough from other sources to conclude that running the engine that cool in the long-term may compromise durability, especially if one is used with other cooling mods such that sustained coolant temperature is below 170 degrees. The problem, as suggested by c4c5specialst elsewhere on the CAC, is piston skirt wear due to long term insufficient piston-to-bore clearance.

That engines loose pistons over long periods of time running at 160-165 degrees indicates that, even if the piston skirts don't fail, internal friction is higher and that extra friction will negate some or all of any of that "incremental" gain one might see.

"Warren S" has posted about a gain of two tenths on the drag strip with the lower temp 'stat, but that's not credible as he made two other changes at the same time and...if the car's a manual, it's really tough to properly test incremental gains because consistency is difficult.
Performance Engineering are clueless.
It is true that, generally, spark timing is advanced is ECT decreases, but in practice the individual cal for the model year and powertrain in question may not have enough difference in the timing commanded for 165 and 186 to make a useful difference.

But...the increased friction and piston skirt durability are not a good tradeoff from the dubious performance "gains" a few suggest are possible.

Bottom line, put a Stant 180 in there and leave it at that.

I guess the boys at Lingenfelter Performance Engineering are clueless.

**warren s** · 02-23-11, 06:44 PM

My apologies to the OP for going off on another t-stat tangent.

As stated dozens of times, putting in a 160 t-stat doesn’t mean your car is running at a coolant temp of 160 degrees. It depends on many factors. I don't drive my Corvette in the cold season. With a properly maintained cooling system and a manual fan control switch along with a colder t-stat like a 160 you can keep the coolant temps much lower and that’s critical to achieving better times at the track if that’s one of your goals. Its idiotic to believe having your engines coolant cycle from ambient temperature to upwards of 245 degrees is a longevity enhancement of any type.

The referred to previous discussions from C4C5specialist are inconclusive at best. The implications is that having a 160 degree t-stat would cause much cooler water to come flooding into the engine in an area that is already much hotter and the resulting contraction of the metal would cause excessive piston scuffing. This is based an a mechanics observation of disassembled engines that were actually still within piston bore tolerance.

It seems very unlikely that a t-stat set to open at 160 would still be closed long enough to allow the rest of the engine to super heat until it pops open and floods the hot parts with the icy cold 160 degree coolant.

As for my results, my t-stat change was part of other modifications that improved my overall performance. On my first C5, the lower temp t-stat, with a manual fan control switch, tb bypass and the zip tie mod was good for 2 tenths in repeated quarter miles passes. Regardless of what a dyno may indicate, being able to control the coolant temperature and keep if from reaching the far end of the spectrum of the LS1s designed acceptable parameters will result in a lower ET. More importantly to me was the enhanced drivability I observed. I only use my Corvette in the summer, mostly in the New York city area where it gets very hot and humid. Keeping the temp below 200 has improved drivability (throttle response), increased gas mileage and lowered my ET at the track.

Most major tuners also recommend the lower temp t-stat for a modified and tuned engines. With all the LS engines out there that have this simple modification its amazing we don’t read about blown engines caused by replacement t-stats daily.