donR

Ok so around 10% which I guess can be worthwile for track times but I guess not alot of gain for the dollar spent and the cars are still very good stock, at least in S/GTS form and the PDK is still very fast.

okie981

I liquidated everything I had bought for track use mods and am using the $$ to build a dedicated track-only 2020 Miata.

okie981

My experience on track in my 981 Boxster:

Mods that might affect straight line acceleration: Cobb Pro Tune by BGB Motorsports, Cargraphic race headers, Porsche PSE exhaust, Porsche OEM air filters, always ran good fresh 93 octane gas with 10% ethanol Texas pump gas typical blend. Engine and PDK otherwise stock.

With these mods on any track and at any outside air temp, I could stay even with any 981 GTS running race headers with any tune the GTS might be running, and against some cars could pull a tiny bit more speed down COTA's 3 long straights.

Against a stock 981 GTS running OEM headers and stock everything else power-wise, I could reliably have a small amount of HP advantage, but nothing dramatic. For example, at the end of the front straight at COTA between T20 and T1, I could reliably pull up on their bumper well before the braking zone if I was 75 feet behind them at exit of T20.

cobalt

^^ I am assuming you are talking about your 16 boxster S and not a base boxster with 2.7L?

A 981 BGTS won't make more max power than a 981 BS. It all depends on what you do to them. Comparing driving skills on track isn't going to say much for which car is more powerful. Everything you describe could have to do with skill, tires, suspension, seats, belts, wear and tear on the car, etc. 14 981 CSM and 15 981 BGTSM both put down the same HP numbers on the mustang dyno with Cobb and pro tune.

Either is quite quick and a relatively easy car to drive fast.

okie981

I'm not sure you understood my post so I'll attempt to clarify. My car is a 981 Boxster S just as my signature says in my posts. My references to power comparison on track have absolutely nothing to do with driver skill or suspension if both drivers have their foot all the way to 100% throttle because my comparisons are only on LONG straights, such as COTA T20 to T1 and T11 to T12. As far as tires or comparative age of the cars, my experience with 981 cars on track on long straights indicates that's pretty much negligible. When both cars have exited the corner and pedal is at 100%, and I know both of us were shifting at typical WOT engine RPM shift points for a long straight, I'm not sure how driver technique or skill can be a factor in comparing which car has more or less or same power? My experiences are real-world, not dyno, and as I said, minimal differences. But after 18 days on track at COTA running with people I know, I have something to back up what I'm saying with respect to 981 S vs. GTS with mods my car had vs. mods those GTS cars had or didn't have. You know, after 500+ laps some trends emerge. Your post compares two cars on dynos. My post compares my car against MANY GTS 981 cars on track.

Please enlighten me.

Kancamagus

True only if your corner exit speed is identical, which is determined by all of the other factors Cobalt was referring to…

okie981

I think you are missing the point of my earlier post. Many laps with others I know, following each other, knowing our consistent lap times and speeds and experiencing how our cars pull down LONG straights, from 50 to 125 mph and 50 to 140 mph at WOT. Trends emerge after hundreds of laps. Anyway guys, you can continue to debate and analyze and critique. I know what I experienced and I know what it means.

cobalt

I have been track driving since the 1980's. You are mistaken if you believe using lap times is an indicator of power differences. As I stated I have two 981's to compare one being an S the other a GTS. We have exhausted the max power we can achieve from either with identical mods being made and they are both within a few HP of each other but there are reasons for the minor power differences and one day one might read slightly more than the other and visa versa . We would need to see what was done to both cars and some form of data acquisition to compare lap times to determine why one is quicker than the other. There are just far too many variables to use lap times as a valid indication of any power differences.

BTW the new Garmin Catalyst is a nice aid that will tell the truth if you both are using them.

various cheeses

Sorry to resurrect a dead thread, but I've been using this stuff ever since I read the thread originally. Looks like it's discontinued though - what's the goto now?

This stuff? https://drivenracingoil.com/i-304978...oz-bottle.html

IndigoInkTaco

Just saw how old this thread was. Disregard lol

davecramer

It may be an old thread, but I would imagine it is still relevant today.

I'll be adding something to my fuel at every fill up now, and changing oil more often,

Charles Navarro

Driven Injector Defender is still available and it's in stock. There was short period of time where we were backordered while they were waiting for their EPA renewal to come through, but that's no longer the case.

https://lnengineering.com/products/d...additives.html

Driven did discontinue the Defender + Booster product due to low demand.

okie981

I use Injector Defender roughly every 5 tanks of gas, add a full bottle to a full tank of gas in the 981. Sometimes I'll substitute Chevron Techron or Redline SP-1 or LiquiMoly Jectron, maybe 1 out of 3 time I use a fuel system additive.

davecramer

car has 75,000 miles. I'm thinking about getting the injectors cleaned professionally, then maintain with additives. Thoughts ?

Charles Navarro

I would recommend against removing the injectors. It's been our experience they usually do not want to come out and if they do, they are usually damaged in the removal process. Worst case, they break off in the head and then you have to have the head removed to fix it, which does happen.

As long as you use a Top Tier fuel and regularly use a fuel additive like Injector Defender with PEA every 2-3k miles, you should be fine. I personally use it every other tank in my port and direct injected vehicles.