I wanted to bring this up cause I have not found much info on here. Most of the info I have found is on non v8 forums, only stuff I have found on here pertains to building boost on the trans brake. Im wondering what some of you guys on here with street cars do to help the car spool faster tune wise. I have seen people mention leaner afr before boost and richer afr. At the same token I have also read of people pulling timing at certin rpm in certin regions of the timing map.what would the proper way to do this on a m6 car? I have thought about pulling 5to10 ° out of my timing table in say the 2500 to 3500 rpm on the map around .76 g/cyl. Problem is im unsure of what a proper amount would be. So lets hear it.i wanna get your guys thoughts

 

This is talked about and a new thread created about once every other month! have a search on here for the following topics:

Quick spool valves
2-step
Anti-lag
best gears for boost
N2O

Also what are you using it for? If you are roll racing maybe you can change your drivng style to better suit the power delievery of the engine. Same gose for Auto X or road courses. drag racing is ocovered on here a lot so you should find ALOT of info.

What is your current setup? Might need to change things fundamentally. AR of turbo, turbo itself, gears, trans, engine, suspension, layout, ECU, all play a part in how a engine behaves with boost.

 

I understand what you are saying,but im more or less trying slightly improve boost response via tuning. I know I can only make it maybe spool 200to500 rpm. Things like anti lag and a two step dont really do any good while driving down the road.
Nitrous is simply a waste of money imo unless your a dedicated drag car. Car is primarily a street car with a rearmount t76.pretty much never sees the track since my local track sucks.I do roll race the car and no problems there I typically brake boost at around 8 psi.
I have been thinking of going to a smaller ar ratio but I dont want to loose too much up top.as far as gearing goes im still running the stock 3.42 and while being a m6 I dont want go any higher due to 6th gear. The main concern is the transition from vacume to boost. Once I hit 1psi the car takes off hard but when before it does it seems just slow down making power for a sec but my logs are not showing me much

 

The downside is that you are creating a timing dead-zone which is probably used by some normal daily driving, but if you can deal with that, then go for it.

0.76 g/cyl sound like around the right area. To be sure, you should log the g/cyl, RPM and MAP. You'll want to pull timing before you MAP goes over 105 kpa or so. Also, I would try and keep the timing pulls in the higher g/cyl areas if you can - this will keep it out of the daily driving area of the map.

I would start with a 10 deg timing pull and keep subtracting in 5 deg steps from there until you either hit the stutter or get the spooling response you want. You may have to cut into the timing quite a bit at first, but eventually you'll hit the timing point where it starts to noticeably affect spool.

 

I've heard good things about wrapped exhausts and rear mounts if you haven't tried that already.

 

Stock manifolds + wrapped y pipe to turbo helps A **** ton

 

Thanks for the replys. I am running stock manis and everything is wrapped good.
The .76g/cyl is the lowest cell I have seen boost in. I figure the 2500 to 3500 rpm range probly would be fine for street driving. Seems like the highest I rev it to while driving normally is about 2200rpm. Im gonna give it a try this weekend

 

rig up a solinoid that is to a normally closed hobbs switch. use co2 and a regulator to fore the gate shut until xx psi then have it close the noid and allow the gate to do it's thing. set the regulator to something like 15-20lbs and when you are ready to race crack open the valve and turn on the hobbs switch.

could build something like this CHEAP and I assure you it will reduce spool time dramatically not having the gate cracking early.

 

you could do that much easier with an Eboost 2 boost controller

 

I wouldn't pull any timing like you are speaking about. If you are referring to where I have said pull a certain amount of timing out on the transbrake I understand where you might of gotten confused a little.

Pulling timing in a M6 car to build boost really only works on the 2 step with rich afr's.

I would actually wait till 2-3psi before pulling any timing. Log where it starts to make 2-4psi and note g/cyl and rpm it does this at. Load will be different in certain gears so it will take some playing with.

Can you take a screen shot of your timing table or if it's in HPT can you post up a tune file to see where the timing is now?

Wouldn't mind looking at your VE table and BE tables to see what the AFR is at those values also.

Cam timing plays the biggest part in this in a M6 car, but you can tune around it.

Nitroused383 would probably be the best person to talk to about this.

He has played around a lot with this in his turbo M6 car.

 

Thanks,thats some very good info to know,i believe where i first heard about pulling timing for spool is in a thread you posted in. its had me wondering and i have read of some of the evo people doing something similar.i deffinetly will try doing what you said in regards to waiting to pull timing till 2-3 psi.
i attached a my tune file for you to take a look at. one thing i have noticed is on a previous file i had set up it seemed to run stronger.but i am unsure if the lag i am feeling now is due to something in my current tune i changed or if it started after i gapped my tr6 plugs down to .028 to try and eliminate blow out.the file may or may not look bad idk since im new to tuning but im getting the hang of it and all in all im pretty happy with the way the car is running besides this issue and that i need to add a little more fuel up top.if the timing table looks jacked its because its a timing table for a lq4 but i actually added a little timing to higher g/cyl regions,the stock table was in the negitives and im getting very little knock in random spots so im ironing that out

 

i currently have a mbc in the car and when i had it turned up to dial in fueling it deffinitly helped spool out but its currently shut off till i get my br7ef plugs in the car because it would blow out spark at less boost than i run know because it was spooling alot faster,but i do plan on getting a eboost 2 some time this summer

 

yeah on the eboost2, you can control the cracking pressure (when the WG opens), the sensitivity (how quickly it reacts to changes in boost), peak pressure obviously, you can fix boost dropoff if your hp or tq cure falls flat, you can add boost in a desired RPM range, along with 100 other functions like meth, boost by gear, multiple boost settings, etc.

We were able to "tune" the turbo just like you tune the pcm to get the most out of it. We made probably 20 dyno pulls trying different combos. That thing is pretty amazing for only $400 ish

 

As Killer LS1 has said with the Eboost you will really be able to see a difference because of the finite control you have over what the wastegate is doing.

The main reason you really can't use the negative timing, rich afr on the 2 step with a stock pcm is that if you use that method to spool it, the rpm region you're going to be in spooling it, you will probably end up falling back into that range on each shift thus going into negative timing and possibly too rich. Now maybe you or I could play with it and try and spool it in the 3500-4500 range. I'd doubt you'd ever see that during a run. If you have HPT and you are tuning it yourself you can load a tune for track use only that will spool it fine with negative timing and rich afr and when I say rich I mean rich....11.0>

Ok I looked at the tune, it's not bad by any means, but is that the timing table you're running right now? If so I found the problem for sure of why it won't spool.

What AFR are you seeing at boost under WOT, it looks like it's commanding BE AFR of 11.61 above 105kpa? Looks like PE AFR is set at 12.5-12.6 IIRC?

 

Under boost im typically seeing about 11.7 plus or minus a tad. Im wanting to get it around 11.4 in boost since I run pump only. Commanded afr in be iirc is 11.6 at the moment and on pe is set to 12.6 ish. The timing table does look funny. Its a timing table for a 01 lq4. It seems to have alot less timing than your typical fbody file.I decided to run that table since im running a stock lq4 long block and figured it would be a better starting point due to the stock heads and cam. Sounds like I should go back to a fbody table thats more aggressive. thats a good point about the fpm range tho with dumping timing, I didnt even think of that.

 

If you do pull a ton of timing and add fuel before building boost it will help spool time. I do it on the import cars and you can get a noticeable difference in spool time.

If you want to get fancy - I've never done it, but I don't see why it couldn't work. Sorta the inverse of a nitrous timing system.

Use a WOT switch (NOS sells them) to activate a relay in parallel to your IAT sensor circuit. Size the resistor to dump the IAT signal to the far left of your IAT table (the coldest). Adjust this far left column to pull an obscene amount of timing.

Next, use a Hobs switch wired in series with the IAT relay to disable the relay above a certain boost pressure (say 2 psi or so).

This system (if it works) would kick your timing down 10-20 degrees when you smash the gas and add a bunch of fuel (because the computer thinks it is cold) and as soon as the boost comes in and activates the Hobs switch, ramp your timing back to normal settings.

It also wouldn't be affected by around town driving because it would only activate when you push your foot to the floor and activate the WOT switch.

Just thinking outloud here....

 

Very keen idea, thanks for sharing, I might give that a try

 

Great idea!!!! That seems to be the solution for having only one timing table with our stock pcm's.

OP if you want I will make you up a timing table, save it in an excel file and you can copy and paste it into your tune. How does that sound?

If you're are seeing 11.6-11.7 now leave it alone. That is fine for pump gas.

 

Stangtrader try this timing table and report back.

It's an excel file so just open it in excel, highlight all the cells and copy and paste it into your high octane timing table and keep the old timing table you had in the low octane timing table.

Nevermind I can't attach it on here, do you have an email I can send this excel file to?

 

that would be awsome. my email is joe.kettenhofen@gmail.com

thanks for all your input thats one reason i love this site.