I have a very simple question

[jeffmsp]

that everyone seems to have different opinions on. Will my motor blow up running with my current mods plus dsms a/f controller w/ 10psi map? I will be well over 225whp, which seems to be the typical "breaking point" from what i have gathered reading through old posts etc. but none seem to have as many supporting mods as I do, and the a/f controller should be a vast improvement over the stock maps. I was planning on doing this regardless, but i am no longer in a situation where i can afford to have my car off the road,and spend all the time putting in a new motor etc. it would mean financial suicide for me (not the price of the motor, but i have to be at work everyday or else im ****** royally-contracts etc.) and blowing a motor that has 40k on it isnt on my list of things to do.

 

[jersey_emt]

I don't see why it wouldn't hold up as long as your smart about it. Don't go boosting up hills in 5th gear all the time and she should hold.

*should*

I say go for it. If it's running good now with all the mods, it probably means you don't have any crazy defects in the engine. I think some of the people who have blown motors have had a true defect that made itself known much quicker because of the extra wear-and-tear from mods. But if you've been running strong with all the mods you have right now, I don't see any reason why you shouldn't go ahead with it.

 

[BOOSTR]

As you know from reading this forum, anything is possible. You have to pay to play and like you said, you cannot afford to rebuild.

So, limit your 10psi boosting to short burst and don't make it a daily driving practice. Get a two stage boost controller and keep stage one at stock psi level and stage two can be set higher. Thats what I have. Over 40,600 miles so far without any problems. But you never know with our beloved MSP's!

 

[Swerny]

As you know from reading this forum, anything is possible. You have to pay to play and like you said, you cannot afford to rebuild.

So, limit your 10psi boosting to short burst and don't make it a daily driving practice. Get a two stage boost controller and keep stage one at stock psi level and stage two can be set higher. Thats what I have. Over 40,600 miles so far without any problems. But you never know with our beloved MSP's!

Well said.
I agree, i keep my mods relatively tame because of the fact that I need my car and don't want to deal with blowing it up.
jeff, watch your boost as it's geting colder out man.
I was hitting fuel cut last year with no mods on freezing cold days.

 

[jeffmsp]

got the fcd on there, seems to be working ok for the cold, without it fc is a big problem.

 

[rocketspeed]

You might be OK. Or you might bend a rod. Hard to say. You're pushing the limits.

If you can't afford to have the car KO'd, run 8psi vs. 10 and have some margin for error. IMO, you're even taking a chance at 8psi, but you'll probably run in the 200hp range and will be reasonably sure the bottom end will hold together.

 

[Captain KRM P5]

fuel cut defenders are the great satan IMO

think about getting a wideband o2 sensor / gauge combo and watching your air/fuel ratios. IIRC there is even a bung on the msp exhaust where one can be screwed in

 

[RyanJayG]

also supporting mods or not. you'll be pushing what the rods can handle even with a perfect tune. yes, some have pushed it to 14 psi on the stock turbo, but yet others have blown rods at much lower psi.

its your car, to gamble or not to gamble.

however if you do go easy on it load wise, it will hold a lot longer.

 

[jeffmsp]

fuel cut defenders are the great satan IMO

Why is that? I think ive got mine working ok, kicks in around 13 its hot out, 12 when its cold and doesnt seem to be leaning me out too much, no pinging. with the a/f controller i would through it out though.

 

[MSP #167]

i have pretty much the same mods as you minus the catback.

I also have dsm's afc and a greddy profec b that holds at 10 psi pefectly and spikes to 10.2 some times. Car feels so good right now.

I feel confident that i am not going to have any problems.

I'm going to dyno it next week to see what i put down. And then i am going to send dsm the af chart, and he said he will make me a custom map.

I really don't push the car that hard all the time, i never boost in 5th, i barely boost in 4th.

 

[BlkZoomZoom]

Because fuel cut is there for a reason. It is there because they felt that was the maximum safe amount of air to go into the engine. The fcd allows more air to go in, without adding fuel for the increased air. The stock rods are literally smaller than my index finger....

 

[Captain KRM P5]

Because fuel cut is there for a reason. It is there because they felt that was the maximum safe amount of air to go into the engine. The fcd allows more air to go in, without adding fuel for the increased air. The stock rods are literally smaller than my index finger....

bingo. i have a few curled FSDE rods on my bookcase as a reminder of what happens when boost goes bad on this car.

 

[UnNaturalinc]

One word: Tuning.

 

[BlkZoomZoom]

No matter how good the tuning, it doesn't change the fact the rods are thinner than my index finger.

 

[UnNaturalinc]

No matter how good the tuning, it doesn't change the fact the rods are thinner than my index finger.

With proper tuning and the mods he's asking about there shouldn't be an issue with stock rods.

Regardless... tuning is key. :shrug:

 

[BlkZoomZoom]

I bent all four of mine at 13psi on the stock turbo... Tuning? Well there wasn't any detonation marks.

 

[girth]

You answered your own question IMO - if you can't afford to rebuild it right now, then you shouldn't be boosting what you are. Yeah it might hold. It also might not.

 

[edaddeemsp]

IMO, i'd put the boost back to stock for these colder months, and maybe push it up to 8psi when it starts to get warmer. The same worries that you have are the same reasons that i'm trying to bullet-proof my motor before any of these parts get bolted on. I've had issues with my car while it retains "almost" stock conditions, and like that i can take it back to mazda, get a rental, and not have any down-time.

 

[UnNaturalinc]

I bent all four of mine at 13psi on the stock turbo... Tuning? Well there wasn't any detonation marks.

I'm sorry to hear that. Blowing motors sucks, fortunately I have never had to deal with that.

What did you have for engine management? There are plenty of people running 12psi or so with out any problems at all (myself included). No, these motors are not indestructible, but they can take a good level of upgrade. People have been modding/boosting these motors since the early/mid 90's.

 

[BlkZoomZoom]

for right around 320 runs I was using my own sensor tricks with resistors and boost pressure switches. For the last 11 I used the MPI. I'm pretty sure I hit the limit of the stock rods, I don't think any better tuning combination would have changed that fact. To run a 107mph in the 1/4, you have to pushing some good numbers.