TIII 2.5 vs TIII 2.2????

[turbovanman²]

It has been suggested that the 2.2 TIII in my van would be enough, IE torque etc. I think the 2.5 would be a better choice due to the sheer weight-3600 lbs and the fact its an auto and I tow with it. Also, I believe the torque will be lower down on the 2.5 which will help with the towing aspect. Either way, I have to either buy new pistons as I don't have any good standard bore blocks and I either wire up the TIII computer to run the 2.2L and modify the trans for the crank sensor, make a jig or get a custom cal, which is no big deal and run a distributor. Sigh, this was supposed to be easy, lol!

[belvedere383]

i think the only gain in using a 2.5 is that the torque will come in earlier but will fall off sooner. I would personaly do a 2.2, they make almost as much torque as HP in most cases, plus you can rev it a little higher which will help with keeping the turbo in it's range depending on which turbo you are goin to use.

Miles

[Frank]

Ya, it would do good. It will feel more sluggish with a 2.2L near stock power levels, but it will feel good later! Plus it will be way cheaper!

[turbovanman²]

I am not interested in a revver due to its my DD.

[Frank]

I didnt say anything about a rev'er. I said it will feel slugish at stock power levels, however it will feel good when you are running higher power levels. Plus 6500rpms is not a rev'er!

[turbovanman²]

I didnt say anything about a rev'er. I said it will feel slugish at stock power levels, however it will feel good when you are running higher power levels. Plus 6500rpms is not a rev'er!


Well on a TIII 2.2, the engine is coming alive at 6500 rpm, If I run a 2.5L, that would be about the max I would need to rev it. Also, with a 2.2, the power is alot higher up, which for an auto DD, would not be fun. Thats my theory unless someone can inject. If I was going stick, I would keep the 2.2 without blinking, :nod:

[Frank]

The 2.2 and 2.5 is NOT that big of a difference as you stated above.


Frank

[belvedere383]

it really depends on the set-up if you have a good matched 2.2 with the right stall in the trans then it shouldnt matter, how many TD rev past 7000 anyway. I think a 2.2 would be the better choice, unless you really think you need all that torque. What kind of power levels were you looking for anyway, if you were to make mid 300's it would probably be a pretty potent street vehicle. haha

Miles

[Directconnection]

I would personaly do a 2.2, they make almost as much torque as HP in most cases.

Miles

Not true. Every 2.2 I have seen makes more torque than HP, even the T-III 2.2s. The exception to the rule is having a rather large turbo that spools later past the hypotetical torque peak, and/or an induction system that is heavily modified to promote high rpm HP.


I kinda dislike the 2.5, but I'm going to go against others here and suggest the 2.5 because of the weight of the vehicle in question, and also it's an automatic. Add in the poor aerodynamics on the top end as well...

[belvedere383]

Not true. Every 2.2 I have seen makes more torque than HP, even the T-III 2.2s. The exception to the rule is having a rather large turbo that spools later past the hypotetical torque peak, and/or an induction system that is heavily modified to promote high rpm HP.


I kinda dislike the 2.5, but I'm going to go against others here and suggest the 2.5 because of the weight of the vehicle in question, and also it's an automatic. Add in the poor aerodynamics on the top end as well...

well then the torque point has proven, i was kind of under the impression that he was goin big turbo. if he is keeping it relatively stock then what does it matter? If you are keeping it mostly stock then do what you feel you should do, but a big turbo 2.5 isnt what i would do, big turbo's like revs even if revs are 6500 that is better than 5500.

[turbovanman²]

I will be reusing my T3T4 turbo, stage III, 50 trim.

[belvedere383]

i would definately go with a 2.2 then. thats just my 2 cents though.

[GLHSKEN]

Well on a TIII 2.2, the engine is coming alive at 6500 rpm,


6500 COMING alive... Nope... maybe peaking, but that statement is not right.

For your van, I would go 2.5L

[turbovanman²]

6500 COMING alive... Nope... maybe peaking, but that statement is not right.

For your van, I would go 2.5L


There was a bit of sarcasm there Ken but I've driven a 2.2 TIII and the car was still pulling hard at 6500. I bet with the BS's removed you could easily spin it to 7500 or higher. There so much fun, :thumb:

I think I will just stick with my regular plan, 2.5 TIII, it seems it will be the easiest route and Shelgame has a chip for this exact combo, :partywoot:

[belvedere383]

why 2.5? only advantage is a little more torque at lower rpm. lower being 2000-3500. a 2.2 cant come in any later than that anyway?

[turbovanman²]

Anyone have a dyno chart of a stock TIII? Frank, can you plot the differences between a 2.2 and 2.5L using my turbo?

[Directconnection]

Look at Cliff Ramsdell's 2.5 t-III dyno plot for reference. I seem to recall on his initial dyno runs where I videotaped that his peak was well under 6k at the time.

[JuXsA]

2.5

You have a very heavy car with an auto thats going to be a DD. I have no idea why people are even suggesting a 2.2 for you. You are going to want the torque of the 2.5 to move that car... and you said your going to be doing some towing. With a 2.2 how well do you think you will be able to tow stuff at 5000 rpms?

Too bad you have a stg3 wheel. I would only imagine how long it takes to spool that sucker up.

[Frank]

My main reason for suggestion 2.2 was mainly because of the easier and cheaper route for him. That is all.

[turbovanman²]

My main reason for suggestion 2.2 was mainly because of the easier and cheaper route for him. That is all.

It was a good suggestion, hence this thread.

I doubt it will be cheaper due to the fact I need to wiring in the harness and mod the trans so really, its about the same money but I think just swapping pistons is alot easier, :thumb:

So Frank, can you make up some plots of 2.2 to 2.5? :eyebrows:

[Pat]

Simon - my 2.2 T-III with a stock turbo peaked hp around 5700. With a 50 trim/stage III, it peaked at about 6400. It's powerband was definitely with the hybrid is definitely in the 4-7k range with very little drop peak to where I had the dyno operator let off.

For an auto in a van, I'd go with the 2.5, but if you do, I'd definitely go with a tighter converter than what you've been running. You'll probably see full boost and a massive torque spike around 3600 or so. You don't want to miss out on all the fun if you're stalling over 4k!

Pat

[Frank]

Exactly what he said. Go with tight converter. :D hehehehe

Oh and compressor map another time :)

[contraption22]

For towing, 2.5.... for racing, 2.2.

[turbovanman²]

Frank, why out outta! :p

Ok guys, thanks. I will stick with my original plan of a 2.5 TIII. :partywoot: :rockon: :number1:

[Subliminal]

Simon,

You're probably a much better mechanic than I am, but if the 2.2 is much MUCH easier, maybe it'd be worth it to try it.

But if it's just as easy on a 2.5, and you have a calibration for that, that's probably the better route.

I don't know, though. The 2.5 isn't so much more torquey than the 2.2, is it? 15-20 ft. lbs, maybe? Your exhaust upgrades are probably worth at least that.

I dunno though. I'm not sober right now. Feeling really...uhm...gooooooood. Yes, that's it. Gooooooooood.
http://www.joombla.com/gallery/albums/userpics/10149/normal_Stewey-Rocketman.jpg
Good.

[Whorse]

I don't know if the 8V is comparable in torque to the 16V, but Hemidare and I both ran about the exact same times at the race track, me with a 2.2 TIV in a Lebaron, him with a 2.5 T1 in a Shadow, at about 12psi. Granted his car is lighter, but that 2.5 still hit on a lot harder down low than my 2.2. Once it's in boost, they both pulled hard, but the 2.5 made a huge difference out of boost and at under 2k RPM I found. I might not be a guru like a lot of the people here, but that alone would be enough to sell me on a 2.5 for your application.

[iTurbo]

I would also go with the 2.5L. I don't see any difference in price if you have to buy pistons either way, and you probably have a good 2.5L crank already. If I rebuild one of my TIII engines, I will go to 2.5L (Spirit R/T). If I'm not mistaken, Cliff was using stock TIII SBEC in his wagon and was blowing headgaskets from too much spark advance and getting a custom calibration for that application will be difficult.

[Pat]

I would also go with the 2.5L. I don't see any difference in price if you have to buy pistons either way, and you probably have a good 2.5L crank already. If I rebuild one of my TIII engines, I will go to 2.5L (Spirit R/T). If I'm not mistaken, Cliff was using stock TIII SBEC in his wagon and was blowing headgaskets from too much spark advance and getting a custom calibration for that application will be difficult.

I have one of Cindy's 3 bar T-III cals and while it's set up for a 2.2, I bet it would be fine with a 2.5. It's ultra conservative (I feel it's a bit overfueled and under timed for a 2.2) so I'm sure with a little bit of tinkering, it would be pretty nice with a 2.5.

On the other hand, if he's going to stay with SMEC electronics and run a distributor, he'll have a lot more in the way of options for cals. I converted my car to run T-III electronics, but in hindsight, I probably should have stayed SMEC.

[GLHSKEN]

Simon,
I don't know, though. The 2.5 isn't so much more torquey than the 2.2, is it? 15-20 ft. lbs, maybe? Your exhaust upgrades are probably worth at least that.



You are about right on the torque difference on a good set-up. The difference is where it makes that torque. The 2.5 will be several hundred RPM sooner which is what you need for a heavier car/van

[turbovanman²]

I would also go with the 2.5L. I don't see any difference in price if you have to buy pistons either way, and you probably have a good 2.5L crank already. If I rebuild one of my TIII engines, I will go to 2.5L (Spirit R/T). If I'm not mistaken, Cliff was using stock TIII SBEC in his wagon and was blowing headgaskets from too much spark advance and getting a custom calibration for that application will be difficult.


I have one of Cindy's 3 bar T-III cals and while it's set up for a 2.2, I bet it would be fine with a 2.5. It's ultra conservative (I feel it's a bit overfueled and under timed for a 2.2) so I'm sure with a little bit of tinkering, it would be pretty nice with a 2.5.

On the other hand, if he's going to stay with SMEC electronics and run a distributor, he'll have a lot more in the way of options for cals. I converted my car to run T-III electronics, but in hindsight, I probably should have stayed SMEC.


Well I am using the engine in my van now, its all fully built so I will just add hybrid pistons. I will keep the distributor so I will have winter to modify the intake to clear it. Shelgame has a cal for this combo so I can try that or when Paul gets back into it, get him to make me one?
All in all, should be alot of fun. I saw Cliff was having issues and thats another reason I don't want to run the TIII SBEC plus cals are harder to come by as mentioned.
Thanks for all the info and insight guys. :thumb:

[TurboGLH]

I have one of Cindy's 3 bar T-III cals and while it's set up for a 2.2, I bet it would be fine with a 2.5. It's ultra conservative (I feel it's a bit overfueled and under timed for a 2.2) so I'm sure with a little bit of tinkering, it would be pretty nice with a 2.5.

On the other hand, if he's going to stay with SMEC electronics and run a distributor, he'll have a lot more in the way of options for cals. I converted my car to run T-III electronics, but in hindsight, I probably should have stayed SMEC.

Don't count on it. The stock TIII cal had too much timing, but he also tried a trim-cal and the car fell on it's face when you started pulling timing. So you can't remove too much or the car performs like ----, but with enough to make good power it eat's HG's. The higher cyl pressure combined with the 2.2 timing curve is just too much for even a cometic. A stock gasket lasted all of two weeks with only 15psi. The cometic's lasted longer, but failed just as spectacularly as the mopar ones did, with big chunks of the gasket blown out. The car is/was going back to a 2.2 with it's new owner because of the HG problems.

[turbovanman²]

Very interesting Chris. Guess we will see, :eek:

[Pat]

Don't count on it. The stock TIII cal had too much timing, but he also tried a trim-cal and the car fell on it's face when you started pulling timing. So you can't remove too much or the car performs like ----, but with enough to make good power it eat's HG's. The higher cyl pressure combined with the 2.2 timing curve is just too much for even a cometic. A stock gasket lasted all of two weeks with only 15psi. The cometic's lasted longer, but failed just as spectacularly as the mopar ones did, with big chunks of the gasket blown out. The car is/was going back to a 2.2 with it's new owner because of the HG problems.


At WOT, at say 20 psi, my FWD cal has something like 6 degrees less timing than the stock cal does at a pegged map (14.7 psi). I know it's not the ideal, but it's no where near as hot as the factory timing curve.

Pat

[turbovanman²]

Don't count on it. The stock TIII cal had too much timing, but he also tried a trim-cal and the car fell on it's face when you started pulling timing. So you can't remove too much or the car performs like ----, but with enough to make good power it eat's HG's. The higher cyl pressure combined with the 2.2 timing curve is just too much for even a cometic. A stock gasket lasted all of two weeks with only 15psi. The cometic's lasted longer, but failed just as spectacularly as the mopar ones did, with big chunks of the gasket blown out. The car is/was going back to a 2.2 with it's new owner because of the HG problems.

LOL, back from the dead.

I agree about timing, it loves timing and without it, it just doesn't like to pull or run nicely, but no head gasket issues so far, :eyebrows:

[MNmopar]

So Simon, you've been running a 2.5t3 for quite awhile now, right? Can you give us a "cliff-notes" version of your experiences so far with it?

I've talked with a buddy of mine quite a few times about going 2.5 in my iroc rt, and I'm curious what your pluses and minuses would be from your experience.

What exactly do you have going on right now? (cal you're using, did you find adjustable cam gears to be mandatory, etc)

[RoadWarrior222]

Well to summarise (very jokingly) his big long TIII build thread, if you run a 2.5 TIII, your hair will fall out, you'll get a fugged up shoulder, your dog will die, you'll go through several heads, transmissions and torque convertors, and may as well take out a wad of $100 bills and burn them now, and still not run as fast as your 8V setup between breakages... pluses... umm.... keeps him from going out and wasting money on whoring, gambling, booze, food, clothing? :D

[turbovanman²]

So Simon, you've been running a 2.5t3 for quite awhile now, right? Can you give us a "cliff-notes" version of your experiences so far with it?

I've talked with a buddy of mine quite a few times about going 2.5 in my iroc rt, and I'm curious what your pluses and minuses would be from your experience.

What exactly do you have going on right now? (cal you're using, did you find adjustable cam gears to be mandatory, etc)

Ok, I love it but it takes some tinkering if you have an auto and a bigger turbo. 5 speed I think would be alot easier to tune as the converter plays a huge part or run a smaller turbo or try a Holset 351. If I had the energy, I'd try the Holset but the GT turbo is so much fun in boost, its addicting.

I do my own cals using MPTune.

I think all TIII's need adjustable cam gears but if using stock cams and a 5 speed, you can get away with it.

Some combo's loving alot of timing, like my current setup, which is a GT35R, stock head and my stage 1 tri flow cams, this combo is pretty fast, I ran a 14.2@99 leaving with no boost, 2.5 cylinders and 22 psi.

My favourite combo was a fully ported head, stage 2 tri flow cams, header, she pulled to 7500 and was stupid fast at lower boost.

I think its a great combo, 2.5 and a 16 valve head, just be patient tuning.



Well to summarise (very jokingly) his big long TIII build thread, if you run a 2.5 TIII, your hair will fall out, you'll get a fugged up shoulder, your dog will die, you'll go through several heads, transmissions and torque convertors, and may as well take out a wad of $100 bills and burn them now, and still not run as fast as your 8V setup between breakages... pluses... umm.... keeps him from going out and wasting money on whoring, gambling, booze, food, clothing? :D

LOL, its faster than my 8 valve setup and yeah, I broke stuff but you will dragging around 3700 lbs in a tool shed, :D

[MNmopar]

Ok, I love it but it takes some tinkering if you have an auto and a bigger turbo. 5 speed I think would be alot easier to tune as the converter plays a huge part or run a smaller turbo or try a Holset 351. If I had the energy, I'd try the Holset but the GT turbo is so much fun in boost, its addicting.

I do my own cals using MPTune.

I think all TIII's need adjustable cam gears but if using stock cams and a 5 speed, you can get away with it.

Some combo's loving alot of timing, like my current setup, which is a GT35R, stock head and my stage 1 tri flow cams, this combo is pretty fast, I ran a 14.2@99 leaving with no boost, 2.5 cylinders and 22 psi.

My favourite combo was a fully ported head, stage 2 tri flow cams, header, she pulled to 7500 and was stupid fast at lower boost.

I think its a great combo, 2.5 and a 16 valve head, just be patient tuning.




LOL, its faster than my 8 valve setup and yeah, I broke stuff but you will dragging around 3700 lbs in a tool shed, :D

Cool, thanks for the info Simon! I'd be doing a 5 speed when/if I get to it. The main reason for me personally is the extra torque or "oomf" in first gear from a stop. I like a fast spooling turbo and I wouldn't be revving up to 8 grand anyway, so the top end limitations that may be there for others don't bother me. Again, thanks for the info!

[turbovanman²]

The off idle and midrange is great, freeway trolling is fun, :evil: A 5 speed would be insane off idle and midrange, :thumb: