High Compression Stroker

[Locutus78]

I am foreseeing problems with my starter on my new motor. I just had a stroker with 10:1 custom pistons put in my 97 GST, and when we were getting it to start for the first time last night the starter kept binding. Even once we got it up and running if it does not turn over right away the starter binds. My mechanic said that with those pistons this will be a regular occurance. The question is does someone make a "heavy duty" starter for a 2g FWD, or will a N/A or another car maker's starter fit?

 

[JayRolla]

call mitsubishi and see if they even carry higher power starters if you think it would help.
I can see it making sense as of why you say it would be harder to start since the compression stroke would have more resistance, but I dont know to what point would make a difference. I mean yea 10.1 is high, but i wouldnt think the starter would have problems unless you had like 20.1 compression or somethin stupid like that .
I suppose it should be ok though if you have honda guys running around with 13. somethin compression, I mean once a spark hits some fuel its going to handle the rest, so the only way the starter should wear out sooner is if youd have to hold the ignition key in the start position for like 3 or 4 seconds before it catches.

You would think so but thats not the case. Ive seen v8's get rebuilt with higher compression pistons, in the 12.1 and up range and the stock starter would barely turn the motor. It would start but it would take longer and the starter would stress real bad.

 

[nightspeed87]

You would think so but thats not the case. Ive seen v8's get rebuilt with higher compression pistons, in the 12.1 and up range and the stock starter would barely turn the motor. It would start but it would take longer and the starter would stress real bad.

they have four more pistons to turn as well... Maybe a reson.?

 

[JayRolla]

That is so true, didnt think of the more pistons. But the stock starter would turn it before and afterwards it struggled.

 

[miklaver]

i have been running my 10.5:1 pistons in my car with stock starter and never had a problem with it starting. sound like you have a bad ground.oh ya my friend has a 2004 gli with stock turbo pushing 20psi and he is running stock pistons 9.5:1. it is tricky to get the fueling right but if you take your time you could benefit from higher compression. off boost you will have good power still and better fuel economy.

 

[JayRolla]

Off boost, who cares about off boost. JJ

 

[Locutus78]

Well guys she is up and running. MAN what a torque monster, I LOVE IT! I have not got her on the dyno yet, but going off DSMLink's HP and TQ calculations we have it tuned to 375hp/372ft-lb, and that is all that little EVOIII can give me. For those of you that have DSMLink I've attached a 3rd gear pull log. With the starter issue, it still does bind, but only on occasion, most of the time it fires right up, but if it has to try for a second it will normally bind. All in all I am happy with the setup, I will be excited when I put a bigger turbo on

 

[Locutus78]

Ok so I am already shopping for a bigger turbo. A couple of concerns I have are:

The most knock I have seen is .4 of a degree, and that is with these 10:1 pistons and the 16g flowing 22-26psi. The only reason I can guess is that the e316g can not flow enough air to produce a lean knock. Now that I am looking to get a bigger turbo, that can flow enough air, what should I expect?

Traction is my other issue. Right now 1st and 2nd are useless, bit in 3rd it rocks. With the linear power delivery of a 50trim I should still be able to keep 3rd, correct? Now I can support a larger turbo with my engine, but with say a 60-1, the power deliver is slow then bam you get your boost (not so linear), do you think that this will move my "power" gear to 4th, thus making me a freeway only monster. I still want to have from a dig possible, and if I have to wait until 4th that is not feasable.

 

[nightspeed87]

I can imagen your spinning hard, on a 14b at only 14lbs im burning thru first if I gun it. Perhaps try a 54 trim, there often over looked but provide a little more top end than a 50 trim and I believe they are still linear. Considering your stroked with high compression; lag shouldnt be a issue for you also considering the more lag the better launching capabilities youll have. You definitly need a performance intake manifold and perhaps a ported head for that stroker if you still have the small stock 2g mani/ tb; im sure its holding you back. Once you get a 50 trim or bigger though id imagen half of 3rd gear will be spinning also. If it were me id consider investing some money in an lsd and suspension/brakes at this point. Will give you more perfomance per dollar than a bigger turbo considering youll be able to autox it then and get at least a decent 2nd gear pull back and that will make up big at the track.
Oh and that 10.1 comp im sure is making it harder to tune, and your knock thresh hold is real low so becareful with that. A bigger turbo will put less heat so should make it less likely to knock except for that youd be flowing so much air that pump gas will give you problems. But then again Ive heard a 50trim is the pump gas king.

 

[Locutus78]

I already have a Shep stage 2 with Quaife LSD. As far as suspension I have Illuminas, RSDSM Rear sway bar, Suspension Techniques Front sway bar, and Front/Rear tower bars. The car handles very well. I have a 1g manifold, E3o2 all of which are matched and ported to hell. I will be looking into different manifold, but right now my concerns are the power delivery, and weither or not I am going to be able to boost without knock (since the turbo will be able to flow enough air).

 

[nightspeed87]

Damn you have lsd and its still horrible spinning huh? Ima have to consider that issue for my fwd . Well like i said 50 trim is said to be pump gas king, youll be ok with that ( depending on how much your boost your running long as your not getting crazy with it.)

 

[Locutus78]

I think I am going to go with a SCM-6152E. It technically is a 56trim, but with plenty of power, and I should be able to spool the stage 5 turbine with my stroker. Anyone's thoughts?

 

[sawnuoff]

i would say check voltage at starter and the timing. just my 2 cents

 

[Locutus78]

Timing and Voltage are right on.

 

[Tony90TSI]

I think I am going to go with a SCM-6152E. It technically is a 56trim, but with plenty of power, and I should be able to spool the stage 5 turbine with my stroker. Anyone's thoughts?

Honestly i would consider going HUGE witht the turbo. The reason for this is to create lag to save tires. I know you are reading this thinking WTH is this guy thinking. Now i will tell you, the reason i say this is you can limit the PSI(cfm) of the turbo to make the power you want to keep the car from just being silly trying to launch on the streets. What i mean is you can make the car launch on the motor and the turbo start coming on and making power when the car is moving and you have the ability to make the suspension work to hook up. Thats just my plan though for my AWD, i want to make a nice N/A power curve with a high compression motor so i can street drive it with ease off boost, then when i want to race it mix in some "good" fuel and let the turbo work. I would really like to know how it turns out with the bigger turbo and see some dyno numbers. If you dont want to post them feel free to PM me and let me know. Thanks.

As for the starter issue, I dont know. I can give you some advice when me and my dad figure out what is going on with his car. His car does the same thing with 14:1 comp pistons but when it binds up it Shatters the starter and all the teeth on the flywheel. The company thats making the starters says its not possible for him to do it and that we have to be hydralocking the motor. Maybe over the winter we can figure it out though.

 

[nightspeed87]

Yea lag isnt such a bad thing on a fwd car, but once boost hits it will still spin reguardless.
Just get you some drag radials and put the awd front equal length axles and that should give you less spin and torque steer supposably. With your stroker and your current compression ratio, your power curve should be awsome. Should feel faster than a n/t off boost and ten fold more wicket on boost.
As far as the starter, try putting a different starter, i believe I have heard the n/t starters arent as efficent and if you by mistake got one of those on there it will make it harder to start perhaps? To be honest my car doesnt always start right up either. When its cold it starts up fine, but after ive driven it and the engine is fully warmed up and I turn it off then try to turn it back on its sluggish to start and the starter strains a little?!
( But i dont have a fuel pressure solenoid either to help with warm starts so it could be fuel related for you also. )
To help I removed the clutch switch thing and just start the car in nuetral with the clutch up seems to start easier that way.

 

[Locutus78]

Problem with the AWD axles is they are too different on 2g's the swap doesn't work the same on 2g's.

 

[MidShipCivic]

Honda's do stock internaled setups all the time, High compression its hardly a problem, some 100+ octane gas and no probs. Who doesnt run good gas, unless you dont want to be fast.

I want to do a Magnus 2.4L Piston/Rod combo with my 1g AWD on 10:1 .

Good setup Locutus.

 

[nightspeed87]

not everyone can afford 100 octane or even have it readily available . Were talking about an everyday driver here not a track car. Personally Id prefer to run the same set up at the track ( engine/ tune wise ) that id run on the street.

 

[SleeperG]

i think you shoudl just try running a battery with a higher amperage rating.
Battery size is typically assigned to an engine based on the amount of cca's it takes to crank the engine over. The higher the compression, the more amps it takes to turn that motor.
With a strong battery your starter should be able to get all the power it needs to crank that engine.
My original motor was a 2.4dohc 4g64 with factory 10:1 compression.
it used the same starter as 2g 4g63 eclipses.


One thing to look into for traction... is an electronic boost controller.
get one that operates in closed loop.
that way you can have a progressive boost curve and tune it for traction.
Of course they are much more costly than a ball and spring, and definatly more complicated... but a good controller in tandem with your lsd, and you'll be on top of your game.

Sounds liek you ahve one fun setup so far.

What size tires are you running?

 

[Locutus78]

BF Goodrich G-Force T/A KDW 2 235/40 18"
And I am looking into a RPM based EBC (AVC-R).

 

[sonicnofadz]

10.5 compression isn't shit. Just becareful with your tuning. Try using a new battery, and a different starter, you will be suprised

 

[Tony90TSI]

So did you figure out what happened? Any more tuning/dyno time on the car?