Join Date: Jan 2005
Location: Perth County, Ontario
Pushing the 2.7? What to do? Suggestions, Experiences, Theorys... Anything...
Ya 2.7, bad design, sludge, blah blah.... no whining in this thread ok?
If you go back to old school measurements a 2.7 equals close to 165 cubic inches (164.764108359 cubic inches to be exact)
That is 1.21 HP per cubic inch, which would be a good accomplishment for someone with say a 318, which, with this ratio would be making 384 HP.
Now say you had a 318 with 384 HP, what would be left to do? Unless you were going to throw a supercharger or NOS on there, or a really big cam that you couldn't drive on the street, you're pretty much done, but with the 2.7, your just at the beginning.... Chrysler seems to have took all the fun out of this eh?
1 HP per Cubic Inch is the goal of many people, but stock, this engine surpasses that mark, yet you hear cries of shitty performance?? What are you asking of a 165 ci engine???
Anyways, this thread is for the goal of improvement...
*My first mod of this nature will be to change my '98 Intake to a '00 intake with MTV (manifold tuning valve). This should pretty much be the same as if you had both a high rise and a stock intake on an old school engine, only you have electronic control to switch between the two, via an '00 or '01 PCM that can control the MTV. Sure you only gain 1 HP at peak, but in the low-midrange you will gain quite a bit compared to that stock set-up (10-20 HP on the dyno curve?), and there is probably some fuel economy improvements there to.
Now for the questions, are any of these options feasible, worth it, good
* Porting... Port match upper and lower intake, throttle body to upper intake, lower intake to heads.... since I'm switching intakes, this would be convenient...and I'm going to do it anyways, unless there is nothing to grind away...
* Increase rocker arm ratio... like in the old days of changing out some 1.5 rocker arms to 1.6 to get more valve lift. This would require custom rocker arms. I may buy a set of 2.7 heads off a blown 2.7 to play with to see what can be done, which would allow me to check out the porting options of the heads also. I have a friend that is a machinist that could probably make a set.
* 3.5 PCM? Since the 2.7 PCM will run a 3.5 in the engine swap scenarios, what would a 3.5 PCM do for a 2.7? I have no idea..... but if you made mods for more air, the 3.5 PCM could deliver more fuel for you is what I would think...? Also prety much any Dodge PCM will plug into the Trep, so what are the fuel curves, timing, etc on all those engines?
* Cam Regrind.. Now this is out of my price range, but it could be done... lower the base circle to increase lift, alter valve timing, duration....
Again, Chrysler really left no room for improvement IMO, but mabey there is?
Getting 1.21 hp/ci is pretty good, did they leave anything out?