Mods, ET's/trap speeds/diets and a G35 (an imaginary G that is)

[rn79870]

When I get a little bored, my mind goes down crazy paths. Here is the result of today's boredom.

Let's build an imaginary car, for racing at the TRACK. Here are the mods, as well as the (claimed) HP gains that we'll add to a stock 2007/2008 G35. (These figures from the Internet sites for the items – some simply claimed, others from dyno runs.).

Motordyne plenum spacer = 11-15hp Borla Cat Back exhaust = 10 hp Intake, Fujitsu = 9hp High Flow Cats = 5-8 High Flow Headers. = 9 to 13

Total parts cost around $2200/2500. Plus installation, or not.

Total HP added - 44 to 55 HP. That's a total engine output of 350 to 361 HP. (I'm pessimistic about these totals but let's run with them for today.)

Here is a site for computing ET and Trap Speed from HP and weight.It is asking for Rear Wheel HP. I'm guessing 300 to 320 for our imaginary car, and 270 for a stock 2007/2008 G35.

http://www.dragsource.com/inde...iew=5

The results270 HP, 3750 Lb car. (w/driver and oil and some fuel) = 14.002 @ 97.35 (stock)300 HP, 3750 Lb car. (w/driver and oil and some fuel) = 13.52 @ 100.88 (low HP estimate)320 HP, 3750 Lb car. (w/driver and oil and some fuel) = 13.23 @ 103.02 (high HP estimate)

The car weight is a big guess on my part, but I'd bet it is close.

The Ets are obviously under ideal conditions - temp - humidity - etc., but do not seem overly optimistic. The Trap speeds seem a little slow though.

So how much faster is the modified G?103.02 (the max from above) = 151.36 feet/second. 97.35 (the stock results from above) = 142.78 feet/second

14.002 (stock ET) - 13.23 (quickest ET above) = .772 seconds difference. That computes to a 110 foot lead. (.772secs. x 142.78 fps = 110 feet)I.E, IF, at the TRACK,, the two cars were to race, I would expect the modified car to have a 110 foot lead when it crossed the line. That is about 7 car lengths. (assuming a 15.5 ft car length)

Let's take the stock G35 and cut 150 lbs from the weight - less gas, no spare, no jack, driver dieting - etc. We get270 HP 3600 Lb car. 13.813 @ 98.682 MPHCutting 250 lbs from the G would produce - 270 Hp 3500 Lb car. 13.684 @ 99.613 MPH The math shows that a 100 pound decrease = an improvement of .126 seconds, and .87 MPH.

Our imaginary car, at 3500 Lbs. produces results of 12.93 @ 105.417 MPH

I don't know if the claimed gains are accurate, or if you could ever get a VQ35 to 350/360 HP, without F/I (my instincts tells me that these numbers are overly optimistic), but if it were possible, and IF you liked running at the track it would be a fun experiment.

Obviously, this is imaginary, and your mileage (results) may vary. Feel free to correct anything in the above if you feel it is incorrect. One more thing - Drive safely and responsibly.

[gwoods]

Geez looks like you somehow got into my head and stold my thoughts...

One thing I noticed when moding my Hemi.... some of the HP you get from Headers is the SAME HP you get from Cats ect ect...

example, say alone just doing any one of the 3 below exhaust mods gives the below increase. Combined they may only give you 20 additional HP. Does that make sense?

Borla Cat Back exhaust = 10 hp High Flow Cats = 5 High Flow Headers. = 13

I think your estimates are good but I doubt the stock transmission would take 50 additional HP at least an AUTO. Stick shift you might keep it together under the load of 100 additional HP. The rear axle half shafts are the next week spot. Sticky tires and 50 extra HP should be able to snap half shafts all day long.

Jeff

[rn79870]

I was thinking about nominating you to test all this...

[SVTCOBRA]

I was thinking about nominating you to test all this...

Jeff took the bait!!

[rn79870]

example, say alone just doing any one of the 3 below exhaust mods gives the below increase. Combined they may only give you 20 additional HP. Does that make sense?

Yes, that's the "Sum of the parts is more than the sum of the total" thing.

(either that, or somebody was a Liberal Arts major... )

[!979TransAm]

gwoods brought up a good point. We talk upgrades all day, but I haven't seen any thorough threads on drivetrain beefing up to handle added power.

[gwoods]

The G will stay stock unless I hit the lottery! Then it will probably turn into a G37S and two snails will go under the hood.

This car was a comprimise with my wife. After a month of sharing a car with my wife because my truck was down with a toasted transmission and a broken piston I decided to give it up and stop modifing my daily driver. I went car shopping with 2 guidelines 4 seats and something fast enough there would be no need for mods.

I do have a 3rd car, 1965 CJ-5 Jeep that I can do anything too I want. If I want to sell the CJ I can put anything I want in that 3rd garage spot as a toy. But no mods to the G..... and honestly the G is fast enough stock.

The Fujita intake saves cost on air filters and improves gas mileage. The shorter fatter tires improve gas mileage and handling. Otherwise my car is just like any other G at the dealership.

I will not do anything else to the G. Sorry guys. BUT I love to offer advise to people modifing their G and LOVE to see the results of the mods!

[joe603]

Well one of these years I plan on adding FI to my coupe. It's a big cost to overcome at once instead of spreading out the mods.

On the question of how much power the car's drivetrain can handle, 400 rwhp seems to be the accepted number from numerous individuals. Most cars are still fine after the install and thousands of miles. Taking a manual trans. loss into account (8%) you're actually making around 430HP at the crank.

[rn79870]

I'll bet brute power won't be as bad as you think. Speed shifting and banging gears will cause the problems. If they ever make an upgrade to the 5AT (B&M like) then that might be the way to go.