Or you can go the other direction and drop weight. Less Lbs per Hp equals faster car in all aspects, turning, stopping, acceleration...

 

How about some aggressive drop in cams...anyone ever try this out?

 

Without the ability to truly tune the engine, cams would make it run like ****.

 

I didn't say it would exactly run smooth after that but it would certainly increase the power.

 

If the ECU doesnt freak out and retard the timing to all hell to safe mode itself.

 

Spent the morning chatting with one of my Lexus Master Techs and a Porsche tech. We bull****ted about improving power on our cars and they said some interesting stuff.
"The engines are over engineered now days so things like porting and polishing net very little power increase (2-3hp). ECU's are locked so true tuning is hard to accomplish. Intake and exhaust can hurt power output as much as help, if not designed well or adapted well by the ECU. Many small things can be done to have a overall bigger HP output, if you are that committed. Focus on weight and rotational mass for increased ETs"

From personal experience, I know that leaning the AFR to a more perfect 13.1 helps mid range power alot. That headers help increase power accross the board. That intakes make more... noise, same with most exhaust (but I'm sure helps a nominal amount when paired with headers). That the engine bay soaks heat worse than you could imagine (probably your biggest power robber, why IS350's hit 12's on super cold days). And lastly, that there is a lot of weight and rotational mass that can be dropped.

 

I had 5 goes last night at Royal Purple Raceway (1320 feet) here in Houston. Was 80-90F with 50% humidity. Never did any better than a 13.8 and I didn't have any traction issues launching at 2000 RPM while brake-torquing.

Our cars seem really sensitive to heat

 

Your corrected times are 13.5 @102 mph. Not sure what mods you got, but that's pretty impressive.

http://www.dragtimes.com/da-density-...ect+ET+and+MPH


Heat is a power killer for all cars. No way around that. I used to have a truck that ran mid-to-high 12's all day but on hot days, I couldn't crack 13's. Go on cool, low humid days and I could get below 12.5's on street tires.

So based on your runs last night, i wouldn't say the Lexus is anymore sensitive to heat that anything else.

 

Yeah, if you are anything near stock on your car, 13.8 is impressive!
I'm actually louver pressing my hood to release heat. He is right, ALL combustion motors are sensitive to heat conditions. They are roughly 70% heat production/ 30% energy. You change that in anyway, you see big change.

 

Rightt...if it's possible with this car porting, polishing, boring, etc. with no tuning and upping the horsepower then i'm sure it's possible with the 3.5 too...just don't be scared of the sound...

https://www.clublexus.com/forums/is-...g-5-8l-v8.html

 

No one said it was'nt possible, said the net return of power for the money and time invested will ne nominal. Am I going to pull my heads, port them, flow bench test them and pay $800-1000 for 3hp...? Would you? Also, If you change the flow rate and characteristics of the intake manifold and heads too much, you can change the powerband of the car. Say now the engine makes all it's power at 5000-7200 rpm. Does'nt help you cause you can not tune your engine to ever rev that high.

 

Doing engine work makes a lot more sense than taking parts off of a car for weight reduction..That should be your last priority imo.

Yeah I'd rather do engine work obviously and the gain would be much greater than 3 hp.. get real. FYI I believe there is some sorta piggy back system out there that tunes the IS nominally. But opening up the exhaust flow and letting it breathe with an intake and headers is a good start for small gains. I'd say realistically more like 10-15hp.

 

Oh the piggy tuner that I have...smh
If dropping weight is not a priority to you then you have never ACTUALLY raced a thing. Dropping weight helps in every aspect.
For example; 400hp in a 6500lbs vehicle or 300hp in a 3500lbs vehicle. the 3500lbs vehicle will out accel, deccel, and change direction than the 6500lb on.
Also, you should definetly do all that work and then dyno, Prove me wrong on the hp gain numbers.

 

If dropping weight a is priority for you, you have purchase the wrong car. What is the point of buying a sport-luxury sedan that is fairly heavy, expensive to modify, has a V6, and is difficult to tune(Hello piggy-back tuning)? There's only so much weight that can be removed, then you're cutting into the luxury part. Yes, dropping weight makes a difference, but horsepower makes a bigger difference.
I'd rather remove the small amount of stuff that doesn't have a negative impact on my comfort and turbo the car than I would try to desperately tear all the crap out that I could to make the car lighter, because I'd rather buy a different car that has better aftermarket.

 

Agreed. I love my 350 for what it is. It's comfort, great on trips, and quick enough to be fun. Lots amenities so I just drive it. I might do the basic bolt-ons because that's what I do with cars.
Beyond that, it's probably very low return to sacrifice what the car really is, a sport/luxury car that's fun to drive
If I wanted to highly mod a car//truck, I wouldn't chose a Lexus. Just too hard and not a huge aftermarket support and what parts are available are very high priced.