Higher torque 2.5

[Gearjamer]

Ok, it looks like I'm going to be doing the top end on my 2.5 t1 again. This time with a new head. If I'm to set up a NA head to run T1 or better I need at least new exhaust valves or valves from a turbo head.

My question is what would be the best path to get the most torque out of my 2.5 under these condition?

1) I'm keeping my 107k stock short block, I know it's in good shape.

2)I'm keeping my Mitsi turbo it's new with less than 6k on it.

3)I have a fresh full 2.5 exhaust with catco cat and Magnaflo oval.

4)I have a High torque ECU out of a 91 AGS Daytona. Yes it WAS one of only 21 built and no the pick a part yard wouldn't let me buy the whole car :banghead:

5) I will be installing the A568 I got from the same car.

Porting the head with +1 valves maybe an option and keeping the NA cam has been suggested. I'm looking at a ported exhaust manifold and even a ported intake. I have an intercooler from a Turbo Thunderbird. I'm trying to keep it simple. A little extra boost maybe but looking to get improvement from maximizing the efficiency of the stock parts. I don't want to have to do a bunch of fab work. I have too many of those all ready. The car will be my daily driver. I drive 15min each way to work on back road that skirt town. Don't want to give the bicyclist too much of a scare:evil:

[turbovanman²]

Your list is bang on, get some +1mm valves, ported the head to match, even slight porting helps. Ported intake and ex will always help.

The biggest change you should do is put a Garret on, this will help make some nice power and it won't work as hard as the Mitsu, plus when you want to turn it up later, you can.

[GLHNSLHT2]

Why port anything when you have a cork in the exhaust stream known as the Mitsu turbo. I have a 2.5 with a little over a +1mm head, a ported 2 piece intake setup and a small tube header. My Super60 turbo with it's .63 exhaust housing and 1.125" ported wastegate is the restriction now. How do I know? Well it spools like a VNT car. Boost hits at 1700rpms and by 2000 I've got full boost. So if you're gonna port the head and manifolds you're gonna want at least a Garrett if not something bigger. Otherwise keep the mitsu, add a good high flowing front mount I/C and call it good.

The High Torque ECU is cool if the car is bone stock, But if you add an MBC it's pointless. The ECU just allows full boost at a lower rpm vs the low torque ecu because the beefier 5spd tranny allowed mopar to do that without the fear of blowing the tranny up.

[Gearjamer]

I'm trying to keep the cost down. The Mits turbo is new. If I'm not going to get anything with larger valves or porting AND keeping the Mits I won't do the valves or porting. I just want to know what would work with the set up I outlined. I like how the car pulls now. It's got an A413 in it. I can leave the line "soft" punch it @ about 5mph and smoke the drive tire. I'm assuming when I switch to the A568 that I'll feel more at the wheels. I would like to amp that up a little without going crazy. If I'm going to buy a new turbo to go along with a port job then I might as well slap the 2.4 16v head on and do a trim 50. But that would take money away from my other projects.

Thanks for the replys. Even if it's something I'm not going to do I at least know what won't work. What's realy going to blow your mind is I have 2x TE04H Mits that I'm putting on a 3.2 Ford SHO motor and mounting in a 1969 TR6. I was just going to start looking to see if another turbine housing is available to help the exhaust flow. Wasn't one of the vendors listing .63 Turbonetic housings? Will they will fit the Mits?

Thanks again
Bill

[GLHNSLHT2]

Smoking tires comes from a couple things, 1st is instant boost response. With the mitsu you pretty much have that. 2nd is worn out suspension. Allowing the tire to move in a path it's not intended will allow it to slip more which will cause loss of traction easier. But I know what you're going for. That instant torque with no top end feel. Keep the mitsu, add an intercooler out front, a Manual boost controller and have fun till the Auto either blows up, you beef it up, or go to 5spd.

No the .63 housing won't fit a mitsu, it's for a Garrett turbo only. But adding that will only kill the bottom end you're looking for.

[Gearjamer]

Smoking tires comes from a couple things, 1st is instant boost response. With the mitsu you pretty much have that. 2nd is worn out suspension. Allowing the tire to move in a path it's not intended will allow it to slip more which will cause loss of traction easier. But I know what you're going for. That instant torque with no top end feel. Keep the mitsu, add an intercooler out front, a Manual boost controller and have fun till the Auto either blows up, you beef it up, or go to 5spd.

No the .63 housing won't fit a mitsu, it's for a Garrett turbo only. But adding that will only kill the bottom end you're looking for.

Thanks,

BTY the suspension has been completly rebuilt with KYB GR2 struts, Energy suspension bushings, and new half shafts. However, the tires are kinda old :p. Anyway I do have a large spline A568 I'm putting in when I pull the motor to do the head and check the block. I don't need top end. I have other "toys" for that. I believe any car can be fast depending on the money you want to put into it. Right now my money is going to "SHOoTR6". That's what I'm calling the 1969 TR6 I'm building with the SHO motor. I'm happy with the Daytona the way it is minus the blown head gasket.

Bill

[Vigo]

i agree with glhnslht2... if you just like instant response and low end torque (fun on the street, but dont race much) than leave the top end completely alone and just intercool it. The intercooler will make you a little faster and make your HG less likely to fail, and you'll still have that instant low end power.

The mitsu turbo is the single biggest restriction in the stock turbo setup so it's pointless to spend money improving anything else unless you intend to upgrade the mitsu (now or later).

The 5spd will definitely make the car feel faster. 1st gear will become pretty dang touchy, but sounds like you're a fan of tire smoke anyway.

The SHO project sounds like a lot of fun. 2 mitsus would still be on the small side for that motor but with the weight of the car you're putting it in its all just gonna be different degrees of tire smoke anyway. Have fun!

[Gearjamer]

Thanks guys! Yes I LIKE TORQUE! However, the feel of torque is inversely proportional to tire smoke. Ones for the driver the other for spectators. I like the feel of the car "pulling" mostly.

I wish I knew the Mits turbos were such a restriction. I would not have bought the second one. SHO motors like to breath. Can you port the exhaust housing? Thought I saw a vendor that could upgrade the flow of the exhaust on these. Oh well money is spent. We will see how they work and go from there. The damn car is still in pieces anyway.


Bill

[Vigo]

on the sho motor, i would just build the car and experiment with clipping the exhaust wheels on the mitsus if and when you determine they spool too early or die off too quick. the 3.0 in a light car will not NEED the instant boost to move, and clipping on a mitsu isnt too much of a shame because they're practically 'throwaways' so youd have little to lose and something to gain.

As for the one on your dodge.. there's not much to do on the exhaust side to open it up. Considering how annoying they are to R&R, i would save your time and money and just have a better turbo to put on it next time around.

a vague rule of thumb thats good for illustrating a point is that the mitsu only moves enough air for 200-220 crank hp. And it REALLY heats up the air when you push it to that point. As im sure you've seen, turbo sho motors can easily break 400 crank hp. Depending on your ambitions, there may come a day when they'll be limiting you, even with two.

[turbovanman²]

Thanks guys! Yes I LIKE TORQUE! However, the feel of torque is inversely proportional to tire smoke. Ones for the driver the other for spectators. I like the feel of the car "pulling" mostly.

I wish I knew the Mits turbos were such a restriction. I would not have bought the second one. SHO motors like to breath. Can you port the exhaust housing? Thought I saw a vendor that could upgrade the flow of the exhaust on these. Oh well money is spent. We will see how they work and go from there. The damn car is still in pieces anyway.


Bill

A company on ebay was modding them and guaranteed more performance.

[GLHNSLHT2]

http://www.thedodgegarage.com/turbo/turbo_housings.jpg