As most know I like the V8 in my crossfires doing test right now on the 3.90 rear and track times with the V6 with each mod.. I would like to borrow a upper pulley and a lower pulley 178 preferred.
will return after a few runs at the drag strip will post info after each mod showing what each mod does to the car . example runs
V6 stock rear 3.07---80mph-- RPM 2750
V6 with new 3.90--- 80mph--RPM 3500
v6 with mods 1/8 --8.1 @ 88mph


1. srt6 100% stock -V6-3.07 rear-stock intake-93 pump gas -density-altitude1791.56ft-81 degrees-13.32 @ 105.27
2. srt6 100% stock-----v6--3.90 rear ?????? to be done
3. srt6 with mods tune,exhaust,pulleys steert tires ,open rear 3.90,, mods 1/ 8 mile--8.1 @ 88mph

 

Curious as to the ET on the run with the three nineties........ Had them in one of my big block vettes; perfect combo for performance through all the gears.

V6 stock rear 3.07---80mph-- RPM 2750
V6 with new 3.90--- 80mph--RPM 3500

 

this is on the highway not the track
we are testing the 390 rear in # 1 car on the street because the owner does not drag race.
as soon as the 390 gets installed into the # 2 car, it will go to the track,,,, will let u know

 

Where did you find a 3.90 that would fit the housing. That would be a wicked gear for the quarter.

 

hay doc. I found it In a junk yard LOL , did my mods to it and it fits like it was made for it.,, just like the limited diff, it has a small yoke on it,,, but we now have a quick,great fix for that . we have had one in a street srt6 for 3 months now,, next week we put one in my newest srt6 and off to the track , and in march off to the V8 install the biggest thing is we can't get is a wavetrac for ir. not YET.anyway

 

up date on the track but 1/8 mile track
got only one run on STREET TIRES rear ratio 3.90
60' 1.899
330 5.327
1/8 mile 8.131
mph 87.79
mods are;
tune, Needswings lower, ,upper turned down stock pulley
Neewswings headers, downpipes , Heatexchanger
Open 3.90 rear with street tires ,

 

sorry added the mods because everyone know what each mod will do so i just bypassed time and added all of them at once

 

am installing a 3.45 within the next 3 weeks,, then a V8 within the next month or so

3.90 in 1/4 mile: 60' @ 1.896,,,,,330' @ 5.275,,,1/8 mile 8.048 ,,89.64 mph= 12.491 @ 11095

 

Why 3.45 vice 3.90 ?

 

just testing, back when i ran a 3.45 i didn't know about the 3.90 . so foe you and myself i want to know
, I am not fully modded with my now srt6 and I ran 12.4 @ 110 . compared to 100% stock on street tires- 13.2 @105, that is less than a full second i was expecting at least a second better .
I still have street tires,V8 intake, needswings, heat exchanger, headers, down pipes. no cats through resonator and muffler,lower pulley 178 upper pully ( Had my stock one turned down ,so i don't know the mm) Tune by Rudy, 3.90 gear rato manual fuel regulator fuel set at 61psi and my afr's at 12.2
I have a friend with a srt6 with same mods that i have + a killer chiller and he is running the 3.90 rear and drag radials running 12.2 @ ???, the same time he ran with 2.27 gears. he in up north 1000 miles from me so he can not run in the winter so we are trying to find the best rear for our car for it to be the fastest it can be . will keep you updated. jim

 

You would think the higher gear you have the better as long as u have the hp like in the 60's if you had a 327 camaro with 315 gears and you went up to 373 you went faster if you then went up to 410 you went faster .. but with the crossfire it is not happening not like back then. with the crossfire, either the ecu tcu or something is holding the car back. maybe i can find that and unlock it. looking at dragtimes
most srt6 ran 12.3 to 12.1 all with 3.07 rear now with a 3.90 gear i run 12.4 does not make sense.

 

Here is something i found from 2007 back then we only had 3.07 rear for the srt6
by china-town srt6
I have noticed there are far too many people on this site wondering if this car is modable and some that are even discrediting most mods even though most of these people have not even attempted these mods. I did alot VERY quickly on this car and EVERYTHING i have done has made the car faster and faster. This is a guide sort of speak to show somebody how to build a low 12 second crossfire for around 2 grand! I really hope this entry can become a sticky or something that way people can read it and see the FACTS and not opinions.

1. Breaking the car in -
My crossfire had less than 100 miles on it when I bought it. I broke my car in by topping her out before she even hit 200 miles. I was between 155-160 several times and drove the car hard ALL the time. There is a million opinions on breaking in but I though I would just share with everyone how I did mine. I have always done this on anything new I have purchased and have never blown anything up.

2. The next thing I did was a get a baseline on the car and took her to the track. The car ran 13.2@103 if I remember correctly the first time out. At that time there was only 1,200ish miles on her. I had the resonator removed shortly after that track session.

3. I then ordered the needswings cold air intake and put several hundred miles on her very quickly before I went to the track. I knew the car was faster and ran a 12.9@106 with the intake.

4. I then ordered the ASP pulleys (331380) and put several hundred miles on her as well. The car felt twice as fast right away but gained even more with miles. I ran a 12.3@110 with that added.

5. I then sent my ECU into InMotion tuning and had a custom tune done for $500. I went to the track again and ran a 12.2@113 with that added.

Here is the cost breakdown:


Resonator Removed: $150
Intake: $500
Pulley's: $1,000
Tuning: $500

I went from 13.2@103 to 12.2@113 with those above mods and thats a fact.

If you have a standard crossfire (non srt) the fastest way to get a fast car is to trade in on an SRT. No disrespect intended but some of you guys have spend thousands on the non srt model in attempts to build a faster car when it would have been cheaper just to trade in most likely. Even the fastest highly modded non srt xfire runs low 14's high 13's best which even a stock SRT will easily spank.

As far as dynoing goes I say the hell with it. It's good for tuning and thats about it. Let the track show you what she's got.

I hope this helps everyone and if anyone was offended I want to apologize in advance. The point of the above is to provide clarity on the modding potential of the car. If you think the srt is fun stock just wait until you mod it with some or all of the above. There is few feelings better than having such a sleeper and beating unsuspecting "other" sports cars so badly they go back to the dealer just to get there motor checked out...

 

Thanks for sharing. That is a great summary of the benefits of SRT6 mods.

 

3.45 rear installed Thursday, was going to track Sunday but rained out,, I am going tomorrow night ,will post the 3.45 rear gears 1/4 mile run hope to get in a few runs.
-------Mods------
tune
super cooler
separated water system
headers
down pipes no cats
lower pulley
upper pulley
V8 cold air intake
street tires
3.45 rear

 

I got to the track Wed 2-8-2023 with the 3.45 installed.
got to the track at 5pm, they opened 5:15pm, went to tech and go up to the line to run (first in line) ,about 10 or so cars lined up ,a Tesla got next to me, , now comes the screwed up part 8 lanes to race,, lane 1&2 trailer/ slicks,,, lane 3&4 no time cars,,lane 5&6 street cars no slicks or radials, lane 7 jr dragster,,,lane 8 .
so now cars start to fill their lanes and the track personnel guy comes up to me and says we are going to start in about 20 min. it is now 5;45. at 6;15 or close to it the trailer cars start to run,,,then they went to the no time cars then the the jr dragster the to the motorcycle now they they say 5 and 6 load up ,,it is now 7:45 for run #1 crossfire /tesla ,,,,,,,,,,,,,next run crossfire / 69 chevelle
he was so shocked he just gave up , he red lighted and i still beat him out of the hole

 

Those short times....

 

sorry i don't know what u mean short times!

 

60' times.

 

with my V8 my best time ( no slip to prove it) but i ran (10.55 @132) (60' 1.497) and (0 to 60@ 3.298)
60' is different from 0 to 60 ,

 

Now that i have my newest V8 crossfire i will be returning this srt6 back to stock removing the N.W. Headers, N.W. down pipes, and other performance equipment to return it to a stock srt6, then it goes up for sale,,, here are the time slips to show the potential of the car .