FAQ: Modding 101 - How to Increase Acceleration Performance

Don't forget the Torque app. for quick and easy scanning capabilities!
No, I don't get paid to promote it, just a big fan!

AA wrote:

I agree with scanning suggestions. I assumed your Dash Command could display KR, but maybe not.

A good way to scan for KR and also get a new mod is the Aeroforce Interceptor gauge. It looks like just another gauge, but gives full scanning and some logging capability. But you can only scan, not tune:

https://rivperformance.editboard.com/t3986-faq-aeroforce-interceptor-scan-gauge?

Another option is the scangauge II. What's nice is that you can display 4 things at once:


Can be purchased at Autozone($150) or I'm sure you could find it online.

Yes, that's another option, for a really good price. Here's a thread with more info on the ScanGauge II:

https://rivperformance.editboard.com/t4394-faq-scangauge-ll-by-linear-logic?

Maybe I'm wrong, but I'm pretty sure the ScanGauge cannot record data during a run, for playback and analysis like the AeroForce can. So the ScanGauge is basically a read-only data analyzer - still good for the price.

^ correct

the mods i have planned are the basics due to the fact i put over 20000 miles a year on my car. they include but are not limited to:
cam- hoping for suggestions here
smaller pulley- not crazy small but smaller
intercooler (from zzp i think)
underdrive pulleys (not sure if these are made any ideas?)
headers, downpipe, larger cat, full exhaust ( please suggestions on the headers, downpipe and cat? the rest will be custom made)
msd or accel coils and wires (which is better?)
better plugs (suggestions please)
cooler thermostat (180 maybe?)
larger throttle body
tuner( i have no idea where to find one of these, much help needed here)
any other suggestions that will improve the reliabilty of the engine?

i will also be doing the suspension over and besides AA's sway bar links am looking for help, hints and sugestions on that also

Hi Josh. I merged your post with this thread. Read through from Page 1 and you may get a better idea of what you want to do. If not, please ask and someone will fill you in.

Thx!

thanks AA apreciate it much

After adding the downpipe I have decided that a 3.4" should be no problem. My only concern is with the OEM tune.

What are some expected effects of adding the 3.4" with no tune? MPGs? Potential power not available? running too lean or rich?

I am always watching for KR so is there any harm with trying it with no tune?

You would probably be fine without a tune, but having one never hurts. Maybe you could meet up with someone in your area that has a tuner? I would put in a true fenderwell intake first before dropping the pulley though along with 104 plugs (I'm just going off of your sig here).

If I ever get my headers on does everyone agree that a 3.3" would be safe? I plan on doing a port/polish when I get home from vacation and MAYBE (big maybe here) getting the headers on. They have a 3" downpipe on them.

Charlie, my buddy with the GTP is running a 3.5 with similar mods to yours and is seeing a max of 7* of KR on very hot days, which he says he is comfortable with. I would say if youre constantly scanning then there is no harm, but you might not really see any gain over the 3.6. I definitely think with a tune you could get it worked out though. Ill tell scott to do yours next! lol

Matt, i would think the 3.3 might be pushing it. Do you mean P&P the blower? Are you seeing any KR right now? I would think in the colder months it would be ok, but in the dog days of summer it might not be the best. Just my 2 cents

The throttle body and the blower. I'm not seeing any KR right now (according to the torque app. Not sure how much I trust it but....). I want to just spend like a whole day scanning to be sure.

I guess the worst thing that can happen is you scan and realize it wont work, then bump back up to 3.4 or 3.5. I think with a proper tune and all the things you mentioned it would be able to work.

MPG: no real effect. When you are driving for economy, the engine shouldn't be in boost, so it doesn't matter what size pulley you have. Of course, when you get on it, you'll burn more fuel.

Think of the 3.4" as a boost extension, another 3-4 PSI over stock. Our engines make 6-8 PSI stock. A 3.4" pulley is an effective 50% more throttle, or you will hit the old stock WOT mark (6-8 PSI) with only 67% throttle. Once you exceed OEM level boost, you'll be using progressively more fuel than your stock configuration ever could. Example: if when stock you got 5 MPG at WOT, with a 3.4" pulley you'll see 5 MPG at 67%, then 4 MPG, 3 MPG, etc. as you move closer to your new WOT.

Without a PCM tune, you can run the 3.4" no problem. The O2 sensor will give feedback to the PCM, so it will keep A/F in check. BUT - when you go WOT, there is no feedback because the system is in open loop. The PCM relies on the MAFF input and the programmed fuel maps. Obviously, your maps will be skewed since you're making 50% more boost. The maps are factory tuned for the 6-8 PSI range. Once you exceed that value, the maps cannot keep A/F correct, so you run lean. That means knock, KR, and all things bad. But this only happens in the top 1/3 of your throttle.

How bad is it? Depends on how much time you spend in that upper 1/3. If it's 5% of the time, there's little to worry about. If 50% or more of your driving is WOT, you have a serious problem to address. If you scan with torque to get an idea of when the knock occurs, you'll know how much and how often you can use the extra boost. The question that gets asked over an over: if you can't access the extra boost safely, why have it?

Re: pulley size, I once wanted smaller, because more boost = more torque. I tried 3.4", 3.3", 3.2", and 3.1". It feels quicker, but it's sort of an illusion. Increased RPM, breathing mods, and timing advance are what make useable HP, which is what makes your car quicker once moving. Low-end torque from boost is only good for launching from a stop, burn-outs, and higher-pitched whine. With proper tuning, breathing, and RPM mods, our engines can make more power safely on a 3.8" pulley vs. a 3.1" with no tuning!

Personally I would advise against the 3.4 since you still don't have any valve lift mods. But if you really want to, try it and scan anytime you reach for heavy throttle. Watch your KR spikes.

Hi guys I have a 1996 Riviera and I want to turn the boost up by putting a 3.4" pulley on it this spring. anything you guys recommend I should do when I do this or before I do this?

bmcd9179: Read through from Page 1 and you may get a better idea of what you want to do.

Thx!

hi guys, I don't know much about cars but im still learning so bare with me.

ever sense I bought my car 4 months ago it has been slower to faster. ive replaced the fuel pump, egr tube, cold air intake, spark plugs and wires, radiator fluid.
so I have a boost gauge, just a cheap one and it reads 4psi of boost, but I don't know if it is right. I timed my 0 to 60 last night, let me remind you its 30 degrees out, I got 10 seconds, ridiculous... so im on here seeing if any of you guys fixed anything or where a boost leak might be. ive checked all my vacuum lines and boost lines, no leaks, ive sprayed starter fluid everywhere, no revv. so idk. I know my lower intake gaskets are out, so im going to replace those, but someone already told me that has nothing to do with boost.

ive also found one of the bolts on my supercharger snout was really loose, ive fixed that now still no difference, just so you know

First thing - before you start a new thread about something, search for other threads that might have the answer. I did a quick search for "acceleration" and found one of our FAQ threads relates to your question, so I merged your thread to it. Maybe give it a read through.

Next - don't assign colors to your thread titles. Color codes are for admin use only. The reason is so members can more easily find FAQ, Write-Up and Group-Buy threads. If you're not creating one of these thread types, it interferes with the system. Make sense?

So there are so many things that affect 0-60 time. The 4 PSI boost reading is a clue, even if your gauge isn't the best. So get a different gauge - a better gauge. Then you'll know if it's accurate. If you find the engine is really only making 4 PSI, there's your answer. That's why the car is slow. Then you need to find out why the boost isn't there. There's a thread for discussing this.

Scanning. This tells you if your car is seeing knock/KR. That slows you down. You can tell if the PCM is reporting any codes, or if it's getting enough fuel. There are threads for these things, too.

Maybe your engine is "tired" from all the miles. Have a compression check done to verify the cylinders are doing their jobs.

How are you launching the car for 0-60 times? We have a thread discussing this as well.

My advice is make a list of possibilities and check/fix them one at a time. Eventually you'll find the reason for the lack of performance, but you need to be systematic. There is no single reason why a car feels slow. Could be a number of things, depending on any number of other things.

Exactly what AA said, ive ran my stock car to the low 14's with good track prep and air, if youre at density that can become a big determining factor on how you run... 4 psi is half of what you should be making stock.
Vacuum leaks?
New plugs/wires?
Any way to log it?
I've never used any GPS type of device to test my car, just good old atco dragway, and with 150k ive gone 14.3 stock, albeit i know how to extract a number out of a car, but any good running series 2 car should have no problems running a high 14 number easy

Sorry guys still learning I've never had a sight for something like this, this is my second car I have owned, I bought it with my own money, the next step is trying to learn how it runs, I'm buying a scan gauge to know exactly what's going on with my engine, I've learned so much from this sight. Thanks for your help. I apologize

Dont buy a scan gauge, if you have a smart phone buy the 5 dollar torque app and a transmitter and you can see all that you want, pour a gallon of 100% alcohol in to a half tank of gas, run it hard, fill up, put some autolite 104's in with a new fuel filter (15 bucks total), do all the free mods, make your own CAI, put in a 180 non drilled stat, etc... thats a half second

Before you go dumping alcohol into the tank you should resolve your other issues. 4PSI of boost sounds low, so look into that problem first. The system needs to be in proper operating condition before you start modding, otherwise you aren't going to see anything from your mods. There is a lot of information on this site. Read read read.

Yes see I have the 180tstat, but I want to scan first, after reading a lot of what people have done, I want to scan to see what's going on with my car. I'm going to seafoam my car very soon.

I could be getting a lot of knock from my injectors being so dirty, this car has never been maintained very much, just oil changes from an old guy. Not getting enough fuel to match the boost, is what I'm thinking but we'll see, I'm changing my LIM gaskets real soon so I'm going to clean the injectors then.

Hows the car running?

I just changed the lower intake gaskets, got a new actuator, and boost solenoid, fixed egr leak, brake booster leak, cleaned my injectors replaced fuel pump, got new tires, now I'm saving up for shocks, they seriously bounce six times if I push down on the back of the car, I'm now running 5 to 6psi in first gear and 8 in second is that normal? Another thing is I'm 0 to 60 in 8.4 which is alright but I think it's because of my shocks, when I launch all the power drops the back end down, haha. My car feels good tho, vibrates at a stop but I'm gonna try and replace all my spark plugs and wires again and see what happens