BUILD THREAD 86 GP 2+2~Blown 6.0

[81cutlass]

I was thinking about you mentioning it bogging and it brought up some questions/comments.

You're making boost on the 2 step correct?
You don't have any launch timing retard with HP Tuners correct?
Can you see where the 2 step turns off in the logs and where is the boost and timing when that occurs?

Bogging - smh. I look at an LSA or blower of any type as instant boost that is rpm dependent, not load dependent. I thought of the heck of a time I have not spinning with my launch retard putting timing down to nothing and I'm still blowing the tires off. But bogging, I've never even came to close to that other than when I've added about double the fuel it needs. If I use a normal timing curve for boost where I'm at 20 degrees at 5psi, which is where I've been launching at, and I turn of off the launch retard, then I'll turn the tires to instant smoke with a 5.3. So when I consider that you have a 6.0 and you're getting it to bog on the hit has me thinking you have a tune issue or 2 step release issue.

The most boost I've been able to get on my 3rd gear spool mod with all of the Co2 pounding on the gate is 16 psi, and I've let go of the brake at that level twice - that was some very smokey events. I have taken out too much timing by a crap ton and made for a slow take off, but I'm talking about launching at 2 degrees.

It does make boost on the 2 step, yes. 10psi and 10 degrees at 3500/4000 rpm. It generally makes the same boost everywhere under load (when the boost bypass valve opens). If I am at 2300 RPM WOT it makes 10psi, and if I am at 6400 WOT it makes 10psi.

I don't have any launch timing retard on purpose. It has 10 degrees in it at 3500/4000 at 10psi. (more on that later).

I can't SEE when the 2 step is turning off with a on/off signal, but if the engine is below 3500 there is nothing stopping it from revving up, and if it is above 3500 it must not be active.

Essentially the 2step turns off as soon as a dump the clutch. If the wheel speed isn't there to blitz the tire off the launch it rolls forward a few feet until the clutch grabs and then the engine gets lugged down to 2000-2500 rpm and it just doesn't seem to have any power there so it slowly accelerates and I just flat out loose time.

Something I never looked at until you mentioned, is what timing I have in when it is bogging. I have always considered it a power issue because it's not making that much at that low of RPM but maybe it has the capability to make power there and I am being too soft with timing so I am leaving power on the table?

I looked and I have like 5 degrees in it at 9psi at 2300 rpm which is what I consider a 'bog'. Maybe I just need to add some timing there? I am just worried that that 8psi on that low of engine RPM is dangerous to throw timing in. Maybe it DOES need 10 degrees? Yikes though, 10psi at 2300 rpm and more aggressive timing might just be a recipe for rods out the pan.

I agree, I should just smoke show the tires when I launch with the level of torque, displacement and boost I am making but that doesn't happen very frequently.

And this is what I consider a spin (this was last fall before i address rear geometry and shocks). 48mph wheel speed in 1st gear, 5800 rpm, 10psi, 13 degrees, time to shift

But I clearly didn't have the car speed because now that the clutch is in the wheels stopped spinning and are only 23mph.

Now the engine has been lugged down to match the wheel speed the car is actually going, it still has 10 psi but 2300 rpm and 4 degrees of timing

And here is one of my better passes going back to '18 with my non flex ECM. It spun right off the hit but was able to keep moving enough that it never pulled below 3100rpm. Eventually it did grab and then accelerated up to the shift point.

Maybe it IS a timing related thing?

 

[64nailhead]

5 degrees makes me take off in slow motion. My rpms never drop, but I’ll assume that is the nature of an automatic rather than a standard.

I wish I had some blower experience. But I have to believe that 5 degrees at 9 psi at 2300 is well too low. The threshold between my slow motion launch with too little timing and blowing the tires off is a fine line - it’s about a 2-3 degree window.

I’d guess with you being on e85 , that you are being too conservative, but Geesh, that’s a guess. Can you find someone else’s tune with an LSA?

 

[81cutlass]

5 degrees makes me take off in slow motion. My rpms never drop, but I’ll assume that is the nature of an automatic rather than a standard.

I wish I had some blower experience. But I have to believe that 5 degrees at 9 psi at 2300 is well too low. The threshold between my slow motion launch with too little timing and blowing the tires off is a fine line - it’s about a 2-3 degree window.

I’d guess with you being on e85 , that you are being too conservative, but Geesh, that’s a guess. Can you find someone else’s tune with an LSA?

I'd love to dial my timing in.

I have looked for LSA tunes on HPtuners (with e85!) but with the EPA going after tuning it looks like HPtuners whitewashed their tune cabinet and they only list stock tunes. HPtuners themselves say they will NOT be allowing aftermarket tunes in their cabinet.

So I need to either test at the track and hope my rods stay in, hire a tuner that knows, or get lucky and find a similar tune.

 

[64nailhead]

There are a bunch on the sloppy tune cabinet. I believe he has the tune file for his Infiniti that is a 4.8 with an LSA. I believe it's a Term X ECU, but you can see the timing table very easily. It seems to be very popular that 1 degree per lb. of boost is a safe starting point on 93 octane. So I'd say if you did the same with E85, then I'd find it almost unimaginable that you will have an issue. Use a safe starting point for max timing of 22 degrees and figure 12 degrees at 10 psi should be beyond safe IMO.

Tune this on the street. I'm sure you should be able to detect a difference from 10-12 degrees and 12-13 degrees.

 

[Northernregal]

Check the sloppy cabinet for combos with 6.0 and small turbine turbos. Should get you close.

 

[motorheadmike]

I'd love to dial my timing in.

I have looked for LSA tunes on HPtuners (with e85!) but with the EPA going after tuning it looks like HPtuners whitewashed their tune cabinet and they only list stock tunes. HPtuners themselves say they will NOT be allowing aftermarket tunes in their cabinet.

So I need to either test at the track and hope my rods stay in, hire a tuner that knows, or get lucky and find a similar tune.

Well now ain't that some sh*t.

How long until Sloppy Mechanics get slammed?

EDIT: Here's the Kitty on the launch control at 4500rpms - that torque reserve can build some torque. Stupid throttle slamming shut... and bog.

 

[81cutlass]

Autocrossed the car at the show formerly known as Car Craft 'arm chair nationals'.

It's a more effective autocross car then a drag car actually. I need more seat time, the car has the set up it needs, I just need to understand how to use it better. For it using the 'UNGN' cheap suspension handbook and adjustable upper front arms with some added caster and 300 treadwear tires it handled better than I expected. No crazy sway, turns in and holds a line well. That's with old 90/10 drag shocks on the front too!!

I started out with a 50 second run due to hitting limp mode, 47 the second, 43 the third and high 42 the 4th. Super prepped mid size muscle cars were in the 37-39 range with good drivers so I'm confident I could get it in the 40's with some seat time. I was about half a second slower than a 06 gto with a driver that has similar lack of experience and those are miles ahead of a g body so what I have is working.

 

[Supercharged111]

An MR2! I had a first gen like that but never did anything with it. I was going to, then I got a Z06 and lost interest in the little stuff. What are you running for an alignment? Those guys killing you by 5 seconds probably have a lot more tire and, like you said, wheel time and familiarity with the car. I bet if you made 5 more runs you'd have seen a couple more seconds drop given the rate you were going.

 

[oldsmobile joe]

An MR2! I had a first gen like that but never did anything with it. I was going to, then I got a Z06 and lost interest in the little stuff. What are you running for an alignment? Those guys killing you by 5 seconds probably have a lot more tire and, like you said, wheel time and familiarity with the car. I bet if you made 5 more runs you'd have seen a couple more seconds drop given the rate you were going.

the blue mr2 in the first pic, iirc, has a 3.0l v6 mated to a 5 spd manual, the kicker is it has the toyota factory supercharger on it also. should be a fun ride.

 

[Supercharged111]

the blue mr2 in the first pic, iirc, has a 3.0l v6 mated to a 5 spd manual, the kicker is it has the toyota factory supercharger on it also. should be a fun ride.

I recall the 2GR swap being popular, but that was a 3.5L. I'm guessing that's a something GR? With the blower that car must get right along.