i was wondering if i could get away with 13:1 compression on 93 octan on my daily.....

motor set up:

b18b bored and sleeved to 84.5mm
wiesco 13:1 pistons
eagle rods
stock ls knife edged crank


gsr head
endyn full port and polish
endyn vlaves
skunk 2 valve springs/retainers
skunk 2 stage 2 cams
webs cam gears
arp head studs


im gonna spray it too... if i do what would be a safe shot for it?
i was thinkin direct port 50/75 shot on a mix of race gas and 93 octan

please give me information on this i wonna build the meanest setup possible and still be a streetable race car...

 

Thats alot of comp.for nitrous

 

lol i know thast why im wondering if i could and what shot would be safe

 

I really wouldn't run 13:1 and the nitrous on 93 octane pump gas. I have NA 13:1 and I only use a minimum of 100 octane unleaded, I might be able to get away with less octane, but with the nitrous I would think at least 100. Even on the 13:1 alone I would at least mix 50/50 with 100 or greater.

 

Let us know. I for one am interested.

 

soo ummm.... you think i could get away with 93 on 13:1? the person that had the motor b4 me he ran pump gas and never had a problem

 

12.5 octane tuned for 93 octane. Tuner informed me that it has a max of 33 degree timing.....could go up to 36 with a 100 octane mix.


Haven't driven the car yet though....I get it back tomorrow. I'll be posting up a full mod list and review from the butt dyno.

 

come on you guys i know people out there know more!

 

motorcycles(street bikes) run pump on over 13:1 comp, reving to like 14k +, and they run fine, its all in the tune. i dont like the bottle on any thing, unless its a beater motor. my old ek hatch dx had a 90 shot on it, bone stock d16. ,thing was a monster, but woudnt put it on a motor i wanted to keep alive. my crf 250 mx bike ran 13.6:1 comp revvin to 13,500rpms, never ran race gas once. just something to think about.

 

I would try to stay under 13:1 if you want to use pump gas. Try to find a sunoco and get 94 octane........talk to the guy who's going to tune your motor. He will know his capabilities.


Modified by TheKINGPin at 11:36 PM 12/6/2005

 

i think im gonan tune with hondata s100 and let tony1 tune it....so wahts safe on a 13:1 sprayin??? im thinkin 75 direct wet shot lol

 

13:1 on 93 octane has been done plenty of times and can be streetable with good tuning. As for the nitrous, I have no clue.

 

Refer to my latest thread for a review of my 12.5 CR motor.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mx621 &raquo;</TD></TR><TR><TD CLASS="quote">motorcycles(street bikes) run pump on over 13:1 comp, reving to like 14k +, and they run fine, its all in the tune. </TD></TR></TABLE>

and the diameter of the bore, and the design of the combustion chamber and piston domes, and the load that the engine sees...

there is more to it than just a "tune."

But I am with DonF, I want to see what happens with 13:1 and NNNNNNAAAAAAAWWWWWWZZZZZ. lol

Pirate

 

goodluck on the 93 pump gas. you can turn down the distribuator
and fully retard it and drive it around but when it comes to racing it,
100 octane and above, i have a 13.4 CR LSV and its hard to daily drive it but u can drive normally on 91 with fully retarded timing but racing it, think about race gas before you turn up timing. and another word of advice, octane boost wont help

and i dont suggest spraying in that motor, your not gonna get anywhere but on the tow truck bed, thats way to high of compression.

 

well as for running the motor on pump gas you will have to pull way to much timing out and it will most likely run like crap without racegas.

and the nitrous go for it i'm planning on doing the same thing with my motor a 12:5to1 2.0 gsr with itb's etc. what alot of people don't know is that nitrous loves compression as long as the bottom end is able to take the abuse and you have time for a lot of tuning with the fuel. the hard part is getting to tune right without it being affected by climate you live in, one day you car could be rich and the next day lean. so as long as your tuner knows hit stuff you should be fine but you will never be able to spray it without race gas because of detnation.

 

MORE INFORMATION!

 

Your setup is gangsta for nitrous I run higher myself. I wouldn't run that on pump gas though! Because with a gsr head you've got more than 13:1 compression if the piston are 13:1 from wisco. I wouldn't try the nitorus without being tuned though and when you tune it empty the tank and make sure you mix the same all the time. I use two 5GL drums myself so its always the same 5gl 91 and 5gl 113.

 

i was thinkin 8gal 93 octan and 2 gal 104 octane......would taht be enough?

 

yes but whatever you tune it on is what you need to run all the time because a different mix will affect the tune

 

You can get it tuned in! How hard will it be to always mix that the same? I find it easier to just get 2 gas cans and work with it that way cause a little bit of leaning out with nitrous could cause some drama in your engine.

 

so when its day to tune do what should i put in just to make sure detination will not happen? half race and half 93?

 

you can run on 93, if you pull the timing way back
but IMO, its pointless. I would just go with lower compression, so you can run around on 93, without having to worry about buying race gas whenever you want to race....just use the giggle juice whenever you want to do that

 

yes and just get two different maps if possible. one for pump gas and pull some timing out for daily driving, and another one for all race gas or a fifty fifty mix of the both when you wanna spray it.

 

When I install my motor I start it out on that from the get go half and half that way I always keep it real close. I try to avoid problems by any means.