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Tuning on this setup...

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420auser

Probationary Member
7
0
Oct 1, 2006
Cochranville, Pennsylvania
Hey guys, I am in the process of rebuilding my engine. I will be using the howell automotive 2.2 Stroker kit, although I have decided to take a different route. I am going to be using high compression pistons (12.5:1) and the cams used for high compression. Every thing in the engine is going to be set and and ready for high compression use. I will also be upgrading my intake and fuel setup (36 lbs injectors, fuel rail, pump, ect...) As for my main question, I was wondering if tuning was needed or if the setup would work with out it. If not, would somebody be able to tell me what piggy back system would be best for my setup? Would I be able to just get a fuel controller or would I need the whole system? The tuner I asked said it is very difficult to tune a OBD 2 car, so how would I have it done. And finally, could I get the timing adjusted at the shop with out gettting a new ecu. Thanks a lot, 420auser.
 
well you better search for a user by the name of bulletdsm and PM him with some questions.


You might want to add an adjustable fuel pressure regulator to your setup for more fine tuning.

And although most of use would be turbo gonig this route , Megasquirt and spark wouldn't be a bad idea for your setup if you do plan on having it tuned. You get the best of both worlds. The ability to adjust fuel, and ignition timing.

Do some research.
 
With such high compression, I would say don't even bother with piggy-back systems. You'd be extraordinarily lucky to not get any knock with piggy-backs alone.

You're looking at MSnS-E (like Rand suggested), Haltech, or AEM EMS for your set up. With 12.5:1 compression, it's all in the tuning.
 
Thanks a lot guys, would you be able to give me a link for the web site to get exactly what I would need, megasquirt wise. Thanks again.
 
Megasquirt is "experimental." There isn't a big company to make pre-manufactured packages with instructions. There is excellent support for MS on the web, but like I said, it isn't like other plug-and-play systems available for other cars. You really need to do your research before diving into this project...

PM me for some details about getting a pre-built MS unit.


http://www.megasquirt.info
 
As a warning, if you're looking to drive this car daily, you may want to SERIOUSLY reconsider that compression ratio. You are going to have to run BETTER than 93 octane fuel ALL THE TIME AND have the ability to modify ignition timing. I've only heard of a couple instances of people installing these pistons and they always end up replacing them due to uncontrollable knock. I have 10.5:1 and get minor knock at part throttle when it's hot out on 91 (the highest I can get in AZ).

Also consider, each point increase in compression ratio will net you 4% more bhp, so if you consider Mark's most recent dyno (169whp) and round it down to 160, 11.5:1 would give you about seven more bhp and 12.5:1 CR would get you something like 14bhp. This is NOT WHEEL HORESPOWER, so you will see gains, but not even 14whp for all the additional trouble that CR is going to be for you.

The way I see it, you are going to HAVE to drop another $400 if you want to daily drive this car on less than 108 octane race gas (at $10/gallon) - a new set of 10.5:1 pistons or Megasquirt'n'Spark.

As a side note, I don't think you'll need injectors that large, either. I'm running stockers with almost 200k on them right now. I suspect that I will have to step up to 24lbers when I start winding the engine beyond factory redline this winter (I have MSnS ready to install), but the stroker motors typically have lower redlines, so you might not have any issues.

Don't give up on things, but give serious thought to what you are about to undertake, as you could be building a car you can't afford to drive that still doesn't make 200whp...
 
Very high compression does require much more agressive tuning to be safe. Unlike going turbo, cylinder pressures will be extremely high throughout the rpm range, even at idle. If incorrectly tuned, you could blow the engine just by starting it up. Higher compressions also means a lower theoretical valve lift limit and/or notching the pistons.

Most people here tend to leans towards boost, so finding info on tuning will be more difficult. If you decide to have a shop tune it, I would recommend an established hot-rod shop, as opposed to a "tuner" shop. The hot-rod shops build high-compression engines every day, and know how to tune a computer.

I think its nice to see people take less established ways to make power. Take your time, dont melt anything, and have luck.
 
Locke said:
The hot-rod shops build high-compression engines every day, and know how to tune a computer.
Not this one. It's not tuneable. He would need a shop that specializes more in reverse electronic engineering to extract the data tables in the ECU, make sense of them, devise new values, and then get them back in and sticking. It's not happening at your friendly, neighborhood rod shop. Sorry.

Absolutely correct on the dangers of high compression, though. I've heard of that CR knocking on 108 at idle...
 
if you want 12.5 compression on a daily driver buy a porsche. I would definately recommend 10.5:1 CR with megasquirt. you could build an all motor car and with the megasquirt system and CR, you could always opt to go turbo as well at a later date with the optimal tuning capabilities of the MSns. either way goodluck and continue to read up on the megasquirt systems.
 
12:5? Ohhhhh.... WTF WTF WTF

The future threads I can forsee already....

Talk to DRIGGS or Bullett...
 
Ok... so it is possible to turbo 10.5:1? How much boost can you run on it? Another question I had was whether or not the 95 RS is OBD I or OBD II? I thought mine was one, but it has an OBD II port? If it is would it be possible to convert it to OBD II?
 
420auser said:
Ok... so it is possible to turbo 10.5:1?

Sure. It'll take some more careful tuning to avoid knock, and you may not be able to boost quite as high with someone with 8.8:1 or less, but turboing a block with 10.5:1 CR is definitely possible.


The 95 DSMs were somewhere between OBDI and OBDII. They can communicate with standard ISO OBDII dataloggers/scanners just fine.

If you get MS or some other standalone, the OBDII system will be rendered useless. It's really only there for emissions testing anyway. If you live in a state where inspections are difficult to pass, you might want to reconsider your plans.
 
420auser said:
Ok... so it is possible to turbo 10.5:1? How much boost can you run on it? Another question I had was whether or not the 95 RS is OBD I or OBD II? I thought mine was one, but it has an OBD II port? If it is would it be possible to convert it to OBD II?
Dude. You really need to search on some of this stuff. We're here to help, but you have to be able to help yourself using existing resources. Running a boosted 8.8:1CR 420A is going to require self-reliance, which you're failing to demonstrate thus far in this thread. I realize you want to have the best set up you can afford and make gobs of power, but right now, you need to focus on the big picture. Only when you can see the whole picture can you begin to zero-in on the details properly.

I think you should be most concerned with concepts such as how turbos actually make power, how compression ratio affects a turbocharged engine and, most importantly, how you want to drive this car when you've got your new engine installed.

Some questions for you to answer that will help us to better help you:

  • How often will you be driving the car once completed?
  • What sort of driving are you building for? Drag? Autocross? Street?

If you can tell us that much, we can all progress much more efficiently. You don't want to be on here talking about shit that isn't going to help you, right? If we know what you're looking to do with the car, where you want to go, then we can share our experiences and tell you how to get there.

Dig?
 
Well I'd really like it to be some what of a daily driver, and I would like to take it to the track every once and a while. I would like roughly 220 whp. I'm not really looking to make major power. Just more then I have.
 
420auser said:
Well I'd really like it to be some what of a daily driver, and I would like to take it to the track every once and a while. I would like roughly 220 whp. I'm not really looking to make major power. Just more then I have.
Okay. Now we're talking!

Did you already purchase the 2.2 from Howell? This is what I would suggest to you, if you're looking at that kind of goal, based on my experience in "the game."

Assuming your engine is healthy*, find a basic Stage 2 turbo system with everything you'll need with it. HRC, Star, or maybe even that Treadstone kit (I'd avoid Concept Ilusions, but that's just me) will take you from making about 105whp, stock, to closer to 170-180whp. That's a nice step towards your goals.

Here's why I would go this route: I assume you were considering this item on the Howell site. That's almost as much as an HRC2 kit. Now, the beauty of going with the HRC kit is simple, tried, true, complete. You get everything you need (although there are things you want to replace up front) AND you get comprehensive instructions on how to install the kit. On the other hand, that motor is going to set you back $2400, but only bring you up to around 110-120whp, at best. You will really feel the difference with the turbosystem. In addition to being very upgradable, the HRC kit gets you boosting closer to your goals and valuable hands-on experience with installing and tuning your car.

I can no express just how valuable that last benefit is to you. Now here's the beauty of it. You were planning to build and boost your car, right? Well, now you have a solid kit installed that is pumping out 7lbs on stock internals. While you're getting familiar with things and, sadly, becoming used to running "only" 7psi, you can be saving up for your rebuild - finding that donor block at the local junk yard, talking to people about a reputble local machine shop to put things together for you when the time comes, etc.. When you finally get that built bottom end ready to drop into your car, you'll also have some nice fuel system upgrades to go with it and, look at you, you're turning the boost up to not 10psi, but 15psi. Now you've just exceeded your goals, but this is okay because your new motor can handle it and you know more about what you're doing. You can dial the boost down to something like 10psi for daily driving, but flip a switch and put the full monty at the track on the weekend with a tank of race gas.

Since one of things we all know is that the boost addiction gets stronger and stronger over time, you're likely going to want to make more power eventually. By looking into projects like Megasquirt and even headwork, you can take things to greater levels if you really want to (I'd advise looking into MS right away, though, as it's less than SAFC and does much, MUCH more for you).

I hope this helps you out. I think it's a simple solution to your problem. You will see greater gains for nearly the same price and gain valuable experience in the process.

*Note: A healthy engine. Invest in a compression tester. They run about $30 from Autozone and can tell you a lot about the internal condition of your engine. If your engine passes the compression test okay, you should be set to boost it with any standard 420A turbo kit for a good while before you pop it.

Good luck to you.
 
I actually already have a motor to swap out and I am looking at the 2.2 Rebuild kit. Would it be better for me to go with the low compression or stay somewhere in the middle. I would like to get the car running with the new engine and then save up for the turbo. I have the money to get the rebuild, machine shop, megasquirt, and fuel system. So would it be better to turbo stock, or rebuild and be ready to throw on the 15 psi.
 
Depends on how long you will have to wait before you turbocharge the car. If it's going to be a year or more, will you be happy waiting that long? You will see more torque from the new motor, but the car will not seem a great deal more powerful for very long.

There's also the question of how long it will take Howell to get these parts to you...
 
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