Chrysler 300M Enthusiasts Club
  • 2003 Chrysler 300m Special.

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LH Performance Modification Discussions
 #368279  by Markster
 July 11th, 2017, 8:45 am
What are some things I could do to make it faster? What turbo could possibly fit?
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 #368282  by 300GEM
 July 11th, 2017, 9:32 am
I second this! My car is a non-Special and sometimes it feels like a slug trying to get up to speed. I know it's a heavy car with a V6 engine, but I often wish I had some more power when accelerating on the highway while merging into traffic. Off the line it's great, but begins to plateau after that.

Off the top of my head, I would suggest maybe installing a cold air intake set-up but I have very limited knowledge about how to go about doing so. There are a great group of guys and gals here that can offer some advice, however!
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 #368310  by Sneke_Eyez
 July 12th, 2017, 11:55 am
There is a Turbo Intrepid and a Turbo Concorde around here.

You can find some information in their threads about the extensive work that they've done to make the turbos work.

Otherwise you've got the following options for increasing performance in some small ways:
1) Cold Air Intake
2) Intake Spacer
3) Bored Throttle Body
4) More Freely-Flowing Exhaust

Bryan can do a 300M Special conversion to his car - 300M Special PCM and 3.89 transfer gears in the Transmission to make it faster.

These aren't the only things you can do.
I really suggest a look through this section and the rest of the forums for additional ideas.
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 #368311  by AustinY97
 July 12th, 2017, 11:58 am
There's also the 4.0L stroker if you want to go down that road.

I'm wondering what the 4.0L cams will do if they really are a direct swap for the 02+ models. Might be something Ill put some money away for...
 #368598  by snstr_auto
 July 21st, 2017, 3:24 pm
'Faster' is subjective.

Do you want 'faster' as in top end? or 'quicker' as in gets moving quicker?

'Quicker' is possible with some of the already mentioned mods, namely the gears. The intake kits and custom exhaust with help marginally in making the car 'quicker' by way of making the engine more efficient.

'Faster' on the other hand is much more difficult. ECM limits top speed, and there isn't namely a quick and easy fix to get a higher top speed out of these cars, save for the Special PCM (and I am sure there is another PCM with a higher top speed) or the unicorn farting rainbow rare 'unregulated' ECM/PCM's to get an even higher top end. The 'easy button' for this is not a cheap one, which is going to a stand alone as I do not believe a piggyback will actually allow for the adjustment of top speed. But with greater velocity comes greater demand on the rest of the vehicle, but that is a topic of discussion for another time.
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 #368604  by In-trepid
 July 21st, 2017, 10:59 pm
I had some discussion at Carlisle with FireM (Bob) and a couple of others about advancing the cams by one tooth. This should be worth a little bit, but the PCM may compensate any potential advancing of the timing electronically. I currently have an engine about ready to go into my other 2004 300M that I will be trying this on. Of course, the bad thing is that I have no direct comparison of performance on the same vehicle as this is an engine rebuild install. It should have like new power anyway and since I didn't have an "M" when it was new I don't know the feel. My only comparison is to a 150,000 mi motor. I'll update when I have some information one way or the other.
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 #368729  by TrueBlue
 July 27th, 2017, 1:14 pm
AustinY97 wrote:I'm wondering what the 4.0L cams will do if they really are a direct swap for the 02+ models.
Direct swap. The gent that did that is a Chrysler tech.
No ideas on gains though.