2.5L to 2.2L conversion

[spoolboy]

Quote:

Originally posted by glhsken LOL for 5 sp's yes... Auto's seem to like the 2.5's... hmmm wonder why... Spoken like a 2.5L auto owner Dennis!! How many 2.2cb cranks you have??

I have 1 I'm ready to part with ASAP.

Another I'm not sure I want to rip out of the engine just yet. It sorta ran still ;-)

Just sent 2 to the big yard in the sky. One was a complete TBI engine and a413.

Garage cleaning.....

My "street" car is a 5spd 2.5. From a roll above 60mph, a 2.5 beats a 2.2 with same mods. Of course if traction is still a problem at 60mph.....

Got some work to do before I put that car back together again, but it should live again before x-mas.

Dennis

[spoolboy]

2.5's make torque

http://www.gtneon.com/pictures/MM2003/mm03-11.JPG

http://www.gtneon.com/pictures/MM2003/mm03-12.JPG

Some things got a little twisted. We fixed it.

I wish I could post pics in threads instead of uploading or posting links.

[glhsken]

Yes they do...

I also watched a 2.2L make 413 ft lbs...

Mine Ill tuned at the time made 340 ft lbs.

LMK what you want for the crank.. I have common blocks.. just need cranks...

what cranks are interchangealbe with what blocks then?

[spoolboy]

Quote:

Originally posted by glhsken LMK what you want for the crank..

I want a 2.5 CB crank that isn't trashed ;-) All it will cost is shipping.

[LeGweg]

Quote:

Originally posted by glhsken Cool.. then his listing needs to be changed as well... ALex, You listening??

Stephane's Charger is not on the TD.com dragtimes page.

1st on top of that list is Dean Stillie's Rampage

[glhsken]

LOL... I just asumed it was without reading...

[LeGweg]

[Mr P-body]

I was talking to a friend of mine at JE pistons and he was telling me that the 2.2L top ring land actually is more prone to detonation because it can trap un-burned fuel between the ring land and the cylinder wall, wich could cause pre-ignition. Even on pro-modified cars that run 40 psi and nitrious. They still have small ring lands and still hold up. I do agree with you on the fact that mabe a cast 2.5L piston could be more prone to breakage do to the material.... not detonation. Also when you look at the deffinition torq it all makes sence about applying twisting force or rotational force to somthing to create energy. Even the deffinition of horsepower is mesured in foot pounds per minute.

Torq : The moment of a force or a measure of it's tendency to produce torsion and rotation about an axis, or applied force.


Horsepower: A unit of power in the U.S customary system , equal to 745.7 watts or 33,000 foot pounds per minute.

So in theory a motor that makes more torq will produce more horsepower....at least thats what our pro-stock dyno shows us here in michigan...like I said at the begining of this post choose by application but I prefere the best of both worlds large cubic inch high torq motor in a light vehicle...

[glhsken]

Quote:

So in theory a motor that makes more torq will produce more horsepower....at least thats what our pro-stock dyno shows us here in michigan

Since HP is simply derived from TQ, of course. Your pro-stock Dyno doesn't differ from the Chassis Dyno I go to in the least. And that's if it makes more torque at the same rpm... 2.2's and 2.5's make peak torque within 1-200 rpm of each other. The 2.2's have a flatter torque curve and make more power at higher rpm's (higher is a relative term with these cars... above 4800 the 2.2 begins to win out)

Quote:

the 2.2L top ring land actually is more prone to detonation because it can trap un-burned fuel between the ring land and the cylinder wall, wich could cause pre-ignition

I believe the operative phrase spelled out earlier in the thread was "susceptible" to damage. Prone was used and it is just a matter of symantics. Even the JE designed 2.5 pistons are more "susceptible" to damage than the JE 2.2 pistons.

[Mr P-body]

let's say I not look at the torq curve of the motor and agree with you that the 2.2L has a better power band, But the motor is not the only thing that make the car excellerate.With proper gearing you could realisticly put both cars in the same range. My high torq motor could be used with a smaller gear and let it run out the back door at a low rpm and still have plenty of power at the begining because of my 400 ft lbs compared to your 375 ft lbs in a light car...:big grin:

[OmniSRT4]

Quote:

Even the best built 2.5's come no where near the RPM of the better built 2.2's (not saying they are revvers either). 2.5's do have monster torque.. but if a mild 2.2 can make 340 ft lbs and a built one makes 418 ft lbs, Why toss the extra 4-500 rpm of power band away?? [/b]

Actually, if you calculate max rpm based on piston speed, the 2.2 is good for 800 more rpm.

Now, why toss that away you ask?

The 2.5 has more displacement and therefore makes up for its rpm loss with additional torque.

In the end, they come out about even. Read below to find out why...

Ive spent far too much time trying to determine the best combo and in the end I have only concluded that it doesnt really matter.

The fact is, if you have 2 engines of equal displacement and power but one has the power higher up, it will be faster because it can use the gear multiplicaton for longer.

However, when comparing a larger lower revving engine with a slightly smaller higher revving engine of the same family, there are no clear winners.

[OmniSRT4]

Quote:

How many 5 sp 2.5L cars are in the 11's... (1 I know of) how many 5 sp 2.2L's are?? 3 I know of.

The main reason for the 2.5 not being good with a 5 speed should be obvious. It has too much torque in the wrong place. Traction is a serious problem with added gear multiplication.

[Zed]

Gearing will even it all out. My 15 psi 2.5 in my old sundance/A413 pulled just as well as Ben Paquins old Lancer which was a A555 2.2 running 5psi more boost than me. For sure he would pull on me above 4K, but below that the dancer would give him fits. :big grin:

[glhsken]

Quote:

Originally posted by Akuma The main reason for the 2.5 not being good with a 5 speed should be obvious. It has too much torque in the wrong place. Traction is a serious problem with added gear multiplication.

Street and strip are 2 different animals... Slicks are a great equalizer for the 2.5. The higher revving 2.2 will win if built equally.