My car has k24/18gs.


I was thinking 60mph roll in 3rd gear is the best spot to run a roll race from?

 

I like 65-70 in third gear personally. Brake boost and let her rip.

 

on k24s i would be at 3k rpm and let her rip.

 

we just tried some short pulls this friday , 60–70 is best on 3rd . but the funny thing is I tried 3–4 and 4th only to 120 mph , same time . both cars no brake boost

 

I find 3K to low of an RPM with 18gs....
I find around 3800 in 2nd to be my best place for the average roll on street racing...

 

I use first gear. But then our first gear's ratio is 3:18-1 and the rest of the tranny has been re geared for the sweet spot.

 

I have no traction 1- beginning of 3rd.

 

The stock trans gear ratio drop between 1st and 2nd is to wide,,to much of a spread/drop in RPMs between shifts for acceleration>> gear recovery. ..Plus the stock first gear is not to good for off the line performance,,,to short..

 

Our first gear ratio takes us to about 75-78 mph. Second goes to 112 mph.

 

each car is different, you want to be in the max boost range when starting, that might be 3000, 4000, 5000 or above... in your case K24/18 should be like 3900-4000 rpms i supose (depending also on suporting mods)

traction is another thing to consider, that depends on tires, weather, track, boost/hp etc
you have to compare all these to your oponent if looking to maximize your win chances, starting in second might be a good idea, but not against a gt-r with perfect shifts and traction and short gears, but might be a good option against a big turbo car with limited traction and a lot of lag between shifts...

normaly you want to start like 40-50mph in second gear or 65-70 in third, all those speeds mean at least 4000 rpms, if you say no traction till 3rd, you got your answer

try to use a semi-slick DOT tire, will give you plenty of traction

 

I wonder why I don't have these traction problems that others encounter with lower HP/TQ then me? Maybe all the dynos I have been on are wrong..LOL..
I have no traction problems with my 18g set-up on 93 pump gas at my best sweet spot to race on the street,,,thats at about 40-45mph ,2nd gear >3,800-4,000 rpm punch...

 

With my gearing on 27.4" tires my sweet spot for 60-130 was 2nd gear because I was almost full boost at 60 and had enough RPM to go to 90 or so before going into 3rd. I was shifting at ~8000 rpm.

 

From lowest to highest reading.......


Mustang Dyno (lowest).............Dyno Jet..........Dyna Pack(highest)



So you may get 625whp on that dynapak but lose to a car that dynoed 580 on a AWD mustang dyno.


My car had right at 600whp and 630wtq on EPL's AWD mustang dyno and I have currently no traction in 1st or 2nd and even half of 3rd.......

Granted its been around 45 degrees consistently here lately.......

 

That's nice gearing, taller, to let the turbo and engine work..
My tires are 26.1 diameter ,,a little better then the stock 24.9 ...

 

LOL....Maybe true Except for the drivers knowing how to race and get the power to the ground,,especially from a stand still race..
A Dyno Dynamics is the lowest and those Dyno packs are the highest..
On a AWD Mustang dyno I made 595 TQ and 550 HP..