ajcool2

iTrader: (11)

Its weird you were having problems with your bigger MAF. I've had mine on for a while now with no drivabilty issues at all. Good info in this thread though.

kacz07

iTrader: (15)

^Could be the cams. I'm trying to read up on some tuning info. If my ROM was based off 1cockyz's (tuned at RT, too), there are significant differences in the lift, though the power is the same. More importantly, this factor might require some tweaks. Could be the tune or could've been the setup. I'd really like to delete the MAF all together and make something custom out of the Cosworth. Do you have cams?

I cleared the learned fuel settings from when I had the CELs and I noticed the low end was a little less fussy after I took a 25-30 mile drive with lots of WOT. I guess I'll see if that helps anything with my setup now.

Got an oil sample for my Mobil 1 0w40 w/ about 1000 miles on it. I also changed my oil to a LubroMoly 5w40.

Zazz93

iTrader: (2)

Just curious Kacz, do you remember if they took manifold pressure when you were tuning? If so, how far were you negative in pressure?

kacz07

iTrader: (15)

Vince said he hooked it up one time when I have the Mrev2/spacer setup and the pressure just oscillated around 0, never went negative and then held. I'm not sure what you'd expect to see or if you'd measure the max negative of those oscillations, but I'd have to believe I'm pulling vacuum at some point.

I'd really like to vent the valve covers or get a vented catch can/oil cap to help with this.

Zazz93

iTrader: (2)

Some tuners use that reading to verify whether there is a bottleneck in the intake system, among other things. For example, just as boost aids an engine (positive pressure), vacuum hurts the performance (negative pressure). Me with a basic non rev-up lower and a MD 5/16 spacer started pulling vacuum around 3500 it continued to get larger to redline. I think I ultimately ended up with -1.3 to -1.4 psi.

kacz07

iTrader: (15)

Yeah, it's hard for me to believe I'm not pulling vacuum with my current setup. Would it oscillate if I had a leak?

I'm going to look into this. If you're pulling 1.3-1.4psi, that's maybe 8-10whp on the table you've yet to unlock, no?

Zazz93

iTrader: (2)

Slight oscilation seems to be about right because the engine is pulling in air cycles. I'd guess that it would be fairly normal to see fluxuations in and around .5 psi. Granted I'd imagine the closer you are to 0 psi the better the engine would perform.

That's what I'm guessing is what's left on the table also. Shawn of Church's Automotive was thinking a bored throttle body may be useful but I'm not sure there's enough material to make that work. He also suggested something like a TB off a larger single neck setup in Nissan fleet, but I'm thinking I'm gonna go the conventional route with a MREV2 or Rev up lower. I'm leaning towards the Revup because it doesn't need a spacer (I hate playing with the strut bar washers). For the right price I'd love to get a used Cosworth as well.

kacz07

iTrader: (15)

I'd really like a custom flow benched and matched Cosworth w/ neck bored and extended out to a GM throttle body setup. At that point, I'd need to ditch the Osiris and go w/ Haltech or ProEFI and tune it by MAP. I'd think the MAF housing diameter would restrict flow, but don't know for sure.

Vince@R/TTuning

iTrader: (7)

I would have to go through this thread to maybe answer all the questions but at the end of the Day the SG headers with the cosworth Manifold gave us the best powerband and the greater amount of usable power over 300whp.

When I say we probably had 6 different Air filter/ Intake configurations that would prob be on the low side.. When I was monitoring Vacuum in the plenum it was never higher the .5in Vacuum, even then it would pulse down and come back up. Typically when there is a air inlet restriction it would taper higher and higher as RPM increased.

As Far as the 3in MAF I think if we played with it a lil more we could have gotten it a lil better. It wasn't so much tune related, I beleive it was more so when we performed the Throttle Ramping, with the cams he had and at the lower RPMs when torque was low it would just hit that spot and hiccup. Very similar to guys running ITB's and big cammed cars...

After talking with Jim Wolf several times and everything we have one this set up, power seems to be on par with the specs of the Cams. The ROM wasn't based off of 1cockyz's ROM. With all the different intake set ups and manifold swaps I probably have 7-8 different Tune for this car...lol

kacz07

iTrader: (15)

HAHA. What's up, Vince?

Yeah, I'm pretty sure I drove you nuts with the changes in the intakes, etc. Thanks for setting the record straight and dealing with my ever revolving intake setups. Think I've got one I like for right now.

I did some datalogging last night to gather a little more info on the low rpm driveability. I logged throttle sensors 1/2, O2 correction and A/F ratio for B1 and B2, engine speed, and vehicle speed. It seems that anything below 3750rpm, regardless of throttle (partial vs. WOT), B1 needs heavy correction, unless I'm decelerating in gear (where it is 100% w/ no correction, both banks). I'm wondering if this could be used to help partial/WOT in these lower rpms.

Above 3750rpm and WOT, the correction is rock solid 100%. Looks like 4k might be the minimum RPM where the N2O would kick in.

Vince@R/TTuning

iTrader: (7)

^^^ Its all good...Im happy with how everything turned out. My only regret is that we (mostly myself) did a better job of documenting every dyno run and the small changes we made. I typically do that when we are doing R and D for a part or trying to compare parts. In the beginning I had no idea we would end up trying multiple configurations on both the intake and exhaust side.

Now that I sent you that ROM disabling codes I wanted you to get it inspected and enjoy the car and drive it for a lil while before we brought ya back. We get get those trims in perfect when ya bring it back for the NO2 tuning. Also anytime your more then half throttle the fuel correction goes to 100% no matter what and goes based off the tuned MAF Values. Also too are the upper O2 sensors only in one runner on the SG headers? How is oil consumption and any leaks present??

Let me know if I can help ya with any thing. Also I still have your shockwave tailpipes... They are safe upstairs...

Zazz93

iTrader: (2)

How did you guys get around the 2.5 inch calculation the ECU is making for the MAF? If the ECU thinks it is measuring air from a 2.5 opening and it is really measuring air from a 3.0 inch opening the results will be unmeasured air going through the engine. Does Up-rev account for that?

Vince@R/TTuning

iTrader: (7)

^^^ yes sir, essentially UPREV allows you to adjust the values for fuel based off MAF voltage. Also the K fuel Multiplier allows for a global change as well. So when you install a larger MAF housing you need to either lower The K fuel or Lower the MAF values across the board to start...then trim in the values at specific voltages from there.

kacz07

iTrader: (15)

Vince, the upper O2s are only reading from one runner of the SGs.

The car is running well. I changed the oil and have driven the car pretty hard for the last 500 miles and there seems to be very little, if any, consumption. Haven't noticed any oil spots on the driveway or wherever I park the car and leave it for a while, too. Gives me a lot of confidence to push it hard during the upcoming track days.

On the straightaways, the car just cruises and revs freely. It's such an unfamiliar feeling to be in 3rd or 4th @ 4.5-5k and know that I've got about half of the powerband left to go. The motor has always been very smooth, regardless of revs, but feels even smoother with the LubroMoly 5w40. I might even try some a little heavier like a Mobil 1 5w50 when I get the results back from this interval. It sounds unbelievable, too! I need to post some more videos.

I'm going to drive the car for an entire oil change interval and then I'll be back. Have to get my windshield replaced and the kit fixed, too (what a headache to deal with this local moron ).

Thanks again, Vince!

SexyRob

iTrader: (11)

ah, always loving having some new juicy NA stuff to read.

kacz07

iTrader: (15)

^+1!!! Can't wait for some of the newer builds to finish up, too. Vince is awesome with sharing his tuning input. This thread has covered a lot of inquiries from myself and its followers. Couldn't be happier with the info on here.

SexyRob

iTrader: (11)

yeah I'm still waiting for funds and time to put my engine together. got most of the parts ready, just trying to figure out what I wanna do for headers/cats

already have strup headers and aam hi-flow cats, but I wanna test ART pipes and some LTHeaders before I get my tune.

gabe3d

iTrader: (8)

I'm gonna try this since one case is free so it's a no brainer. However the weight is not what you are looking for though (10w30 or 20w50)

http://www.valvolinevr1racingoil.com/

kacz07

iTrader: (15)

I would try a 10 or 20 but I worried about cold starts if the car is in NJ or not stored. I originally wanted to try something heavier from LubroMoly, their 10w50, but I settled for something more normal since I am more of less daily driving it right now. I'm wondering if the oil is helping with blowby, want to try something heavier since my car was consuming oil in some form or another.

kacz07

iTrader: (15)

Which are you going to use and why?