JL ws-6

iTrader: (50)

if you HAVE to stay unleaded, that motorsport 103 looks like it's designed for high compression motors. What is your obsession witn the unleaded gas? If you are going to buy a drum and keep it in your garage like I assume you will, what is the big deal? You aren't gonna be driving the car on the street and there's no way even with an unleaded race gas it would ever pass a sniffer test, so what gives?

The C14 would be perfect for what you want to do, and provide you with enough octane so you wouldn't have to worry about anything.

Dragaholic

iTrader: (180)

Because I heard/read that leaded gas ruins/kilss O2s. Is there any reason to run O2s on a race car? I don't necessarily have to run unleaded if I can do away with the O2s, but I want to make sure that I can get rid of them safely. Is there any benefit to getting rid of them?

JL ws-6

iTrader: (50)

you should be tuning the car in open loop, so that none of the o2's are doing anything, it will be alot easier to get it to idle, etc.etc. that way.

Therefore, no need to worry about the o2's. I have been running my car in open loop for over a year and it runs perfect. Plus the tune dosn't have to be adjusted as much that way, because it stays where you set it to, rather then changing itself to try to get an o2 reading that it's looking for.

Dragaholic

iTrader: (180)

I will ask my tuner if he can do that. I don't tune the car. So if I run open loop and get rid of the O2s, what fuel would you recommend then (leaded)?

Also, do I need to put plugs in the O2 holes or just leave them in there? I would think to plug them because whether they're operational or not, the leaded fuel is still going to damage them.

Lastly, what disadvantages are there not running O2s on a race car?

JL ws-6

iTrader: (50)

I'd run the C14 that's on that website you listed. You can plug the holes, that's easy enough to do with a short bolt the right thread. I don't think there really is a disadvantage... alot of guys iwll have a wideband they will hook up to check things now and then, but as long as you are pulling plugs constantly and checking them, and doing all the other regular maintenance you should be doing (haveing injectors flow tested once a year or so, stuff like that) there's no problems.

A wideband, to check on the inital tuning would be a good idea, but once it's set, you should be good to go. And yes that O2 won't last forever either, but they're like 75 bucks and even with the leaded fuel it will still last a long time, if you remove it when you aren't using it.

Dragaholic

iTrader: (180)

Will the C14 be too much for me? I won't spinning 8k rpms or more nor do I have 14:1 and over compression.

JL ws-6

iTrader: (50)

It will be fine... like I said, better to have a little extra when running no knock sensors, and you'll be able to put a degree or 2 more timing to it safely. It's one of those things, run too little, get a drum that's a little off or something like that and if you go with the bare minimum then you could find yourself with not enough, go a little over what's needed and you just have a little added safety margin. Something IMO is a good thing to have when you drop 10 grand on a motor.

If Erik Koeng is building your motor, ask him what he thinks, I'm sure he will agree it's better to have a little too much octane then not enough.

JL ws-6

iTrader: (50)

also what heads did you go with? If you went with ET stuff, we've found those heads really don't like alot of timing, but a little added octane will let you run a little more with them, and really make some pwr.

my 402 is 13.5 to 1, with et 240 heads and with the stock water pump, no vacum pump or any of that, and 1 3/4 headers makes 470 thru a converter that goes to 5400 on the transbrake, th400/12 bolt for drivetrain. fwiw I'm only running 17 degrees of timing as well. We tried more, and it just didn't make enough added power to be worth it (20 degrees only made 475, but it made 470 at 17..... so again, we aired on the side of caution.... no need to set it on kill all the time)

Noyzee

iTrader: (37)

Drag, tell me somthing. exactly what are you doing with this car?

race only, street/race, spray ect.
depending what your doing would give good spots to start.

and i would say screw the tunes in open/closed loop, go right to speed dens, its mint, and it was super easy to get my big *** cam to idle.

JL ws-6

iTrader: (50)

Brad does the speed ednsity use any of the o2's for anything? I suspect it doesn't, and it doesn't use a MAF reading either right? If that's the case, then that is the best way to go for sure... the less electronic stuff that was designed to get the car good gas mileage/low emmissions you can remove, the better a race engine will run. All that crap just causes the computer to get confused and start doing stupid ****.

Noyzee

iTrader: (37)

correct, it uses nothing. plain and simple. you change your fuel (just like changing jets) and you adjust timming (just like a distributor only you stay clean)
its also less restrictions in bellows, mafs ect ect.
im super happy with the speed dens tune. i dont even use my iac any more. just blocked the hole up.
its mint.

Dragaholic

iTrader: (180)

Its a drag only car. No street use. I could care less about driveability/streetablilty or gas mileage. Here's a quick rundown on the setup:

LS3/L92 block (4.065 bore)
Callies 4.00 crank
Callies rods
Wiseco custom dome piston
ARP bolts/studs throughout
Custom HKE cam (254/266 .650 112 +4)
13.5:1 compression
Greg Good LS3/L92 heads titanium intake/Ferra hollow stem exhaust
Patriot Xtreme dual spring kit
L92/LS1 rockers w/Harland Sharp mod
Beck sheet metal intake w/rails

I had already planned on getting rid of the MAF and doing a speed density tune. When I do that, will the O2s be useless then? I want to be able to get rid of the MAF (speed density), get rid of the O2s, run a good leaded fuel, and still get a nice race tune in it.

Noyzee

iTrader: (37)

its an all out race car, heres what to do.
run the best gas possable (110 or more)
start with 7's for plugs, see how they look ect be sure they dont foul or anthing because they are to cold.

id run a race non synthetic oil like the Valvoline vr1 racing oil at a 50 weight so after back to back runs it isnt broken down.ect.
i would change your oil after every 10 passes or less

if you have the cash to build a big dollar motor like you are you mine as well spend the money to keep it up and running good.

Noyzee

iTrader: (37)

as for tuning, i have no maf and no 02's and a much larger cam, and it works mint. i dont have to 2 foot it nothing.

TOS98SS

iTrader: (2)

Awsome thread guys ,some really good info . Thanks

Dragaholic

iTrader: (180)

Not that it matters, but some things I left out:

Melling high volume oil pump
N-Motion timing set
Morel lifters
Moroso oil pan

How can I tell if they are fouled out or not?

I plan on running Valvoline VR1. Is 10W-40 not good?

C12 C14?

What's the specs on your cam?

JL ws-6

iTrader: (50)

c14, noyzee's running a big solid roller

Noyzee

iTrader: (37)

the vr1 is good, just keep up with it.

as for the plugs, when i run 9's with spray if its cold, the car wont fire right away and or run like **** cold.

i run a 7xx solid roller cam

KCFormula

iTrader: (4)

I don't think you need C14 unless you plan on putting a big shot to it. They rate C12 to 15:1 and if you are at 13.5 you should have no problem running on C12.
My car sees a lot of street time and it is in a open loop tune and works just fine. I actually wanted to run 02s and bought those Denzo O2s designed for leaded gas, but I had Allan Futral tune it and he told me those were a waste of money because they don't read as true as the factory ones anyway we decided to go open loop all the time, to tell you the truth I haven't noticed it.

JL ws-6

iTrader: (50)

you can run whatever you want for fuel, but I'd rather have a little added protection. There is the occasion that the fuel does come in a little lower then it's supposed to be, and if it sits around a little longer then it should, you could run into problems if it's right on teh edge of what's needed.

I'd start with the C14, then maybe get a 5 gallon can of the C12 and try it, but if you do try the lower octane fuel, definately go back one range colder on the plug initially.