A Rebuild Story - A Forged MP3 Motor

As soon as I see the MPI limits (within my knowledge or the unit capabilities) I will jump on him.

The only downside I see on the MPI is that if the O2 sensor is bad....the tune doesnt work! so...everything relies on it.
 
The thing I'm really curious about with the guy down there as far as the Microtech is how he got around the alternator and the tachometer issues on the P5. I have some ideas, but am curious as to what he has done.
 
igdrasil said:
As soon as I see the MPI limits (within my knowledge or the unit capabilities) I will jump on him.

The only downside I see on the MPI is that if the O2 sensor is bad....the tune doesnt work! so...everything relies on it.
Click to expand...
Sorry to jack here Steve, but.....

The MPI does not rely on the O2. The TM clamps the voltage and uses that to help add fuel and go into open loop, so I guess there is where it can have a problem. I ran the MPI for a good 8-10 months without the O2 being messed with, before Nick came up with the TM. We tapped into the O2 to get a narrowband reading, but that's it. I was adding fuel via the xtra injectors only during this time. So the SW only used the F2 and F3 maps, no need for O2 signals on those.
 
I think what igdrasil was saying is that becuase the MPI relys on the stock ECU which in turn relies on the O2 that if you lose your O2 you'll lose about half your MPI tune (anything not open loop). So in that sense the MPI does rely on the O2.
 
TurfBurn said:
I think what igdrasil was saying is that becuase the MPI relys on the stock ECU which in turn relies on the O2 that if you lose your O2 you'll lose about half your MPI tune (anything not open loop). So in that sense the MPI does rely on the O2.
Click to expand...
Okay, I get it now. Anything that keeps the stock ECU will have to abide by those rules. The only way to not have to worry about it is an O2 simulator or the good ol stand alone and then that's where you come in!
 
I'm working on a couple of O2 sim's as well.. I have oscilliscope capture of the signals so I can make exact replicas. It'll make it possible to lock the inputs to the ECU so you'll get a single value and then use a different tool to move everything from there! :) It's in the works... but anyway..

Making progress on the rebuild.. I should have my block back this next week (took longer than anticipated... stupid oil squirters!!) and I may have access to some additional funds now that will enable me to get my head done... I'm going to look into whatever I can do get the Toga bearings for my rods and mains, and size all that properly... so hopefully in the next couple weeks you guys should see some major updates on this thread :)

Have a good one!
 
Block is still at the shop and is going to be held now until my pistons come as he is concerned about the clearances that I'll end up with... which I can't blame him. So we are going to check that... Also, we determined in our discussions today that it will be best to o-ring and receiver ring the block and head respectively for the high boost application. Additionally, looking over the head we saw that the exhaust ports are massively undersized relative to the gasket, so it is going to take a considerble amount of material removal to get that right, which is going to make the price go way up on the head work. Other than that, everything else is pretty uneventful. I haven't recieved my rods or crank or the like back yet to do any work in that department.

Later!

Steve
 
zoom zoom boom boom

Ok my motor blew the other day now I have the AEM EMS on a Mazdaspeed now the car was being tuned on a dyno at 14 psi and the rod snapped and flew down through the block and through the oil pan. I was wondering I'm getting the forged internals my question is what would I be able boost safely at and if I were to get the T3/T4 hybrid what would I be able to boost at then. Are forged that much better?
 
boost

Now how would all the extras hold up to about 18 psi with the stock turbo and from what I heard the turbo is insucifient after 18psi would I run into all what was stated in the other discussion.
 
The T25 does supposedly lose too much efficiency after 15 psi to be useful. It apparently can push okay to about 18, but actually makes less power due to the hotter charge. That is the heresay that I've seen to date on it. There are other turbos that should fit into that same basic footprint that can do higher psi. But many of the things we are talking about in the other thread don't apply if you are at or below 18 psi. 15 psi you just really need internals and a decent tune and you'll be fine. Going above that is when you start running into a lot of the bigger issues that we are beginning to see.

Later!

Steve
 
Word of advice, guys: Don't try to go too nuts with the power...until you get traction to be able to use it. Trust me.
 
I'm hoping to maybe roll the fenders and switch to like a 265 tire up front... But the power is/will be good at high speeds racing though... which is my major desire for it.
 
Now if I go with the T3/T4 hybrid and Forged crank, forged pistons and rods and Quife LSD,2600 lb pressure plate and new clutch what else would I need to be safe. I want around 270 whp on a mustang dyno. Or am I being crazy?
 
thats reasonable with those supporting mods. We are one up already because we already have a forged crank.
 
270 horse is about 16 psi ish... we do have a forged crank... you should be generally fine as long as you have a good way to tune your fuel.

Later!

Steve
 
officially subscribed to probably the most helpful link to rebuilding...I hope to building up a block, rather than rebuilding:p, but it will be the same, as I'll just get another block, do the rods and pistions, and hopefully it will come with another crank(the block(, then I can swap her in, sell the old block(or keep it, undecided as of now), and then move along with other things(FMIC, Hardpipes, Greddy Type-S, some form of EBC(undecided as of now), A GT28r(or rs), some bigger injectors, a larger diameter throttle body, hopefully either a Haltech or Microtech, FPR, J&S safeguard, ditch the ACpump, getting one of the local shops help me along with the work, and also the machine work and stuff(theres a few ok looking shops..ie essential speed, and point zero)...and running all of this around 14psi on the street daily, and much higher in race situations...of course, this is only my basic general idea for the future...researche will probably turn up much more stuff I'll need to do and such, but yeah, I'll research alot before my plan goes into motion. Don't be looking at me to be doing this for a while..but when it happens, watch out...it'll go flying into motion. I don't really wanna go peice by peice, but rather, all at once(yes yes, I'm looking at ALOT of ******* money to do this..hence the time period of saving and researching...lol)...I know I'm missing alot of the little stuff(and some big too prolly), but I'm tired, and not thinking....good luck with all the engine rebuilds going on guys...and have fun
 
I'm going to also publish a final price list for everything as well so that you guys have a good budgeting idea. Right now it is shaping up to around 5600.. without a turbo replacement. Right now everything is kind of held up on the pistons.. and how much it is going to cost to do the PandP and valve work on the head.
 
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