Performance increase questions
 

I have a bone stock 98 12 valve...215 hp. Great reliable truck. I'm using the truck for my daily driver to work and also have an enclosed car trailer that I pull. Once every couple years I make a round trip to Alaska pulling a heavy load with a few pretty good hills to pull. I'm not interested in spending an ass load of money and ending up with a 500hp rig. Dependability is important to me and fuel efficiency is important on my Alaska trips. Daily driving...I'm less concerned about fuel mileage since I can use other rigs for economy and my drive to work is short.
I've read a lot of posts and articles here and have a good idea of what I can do for cheap or free to gain some extra HP. I'm old but would enjoy some better black smoke when I mash on it. I don't want to fumigate the neighborhood while I'm off of it and tooling around but there are times when I want to pump out the black. I'd also like to get a quicker response when I mash on it. It just seems like it lags a bit to me.
I've read that I can get about 100 free HP by moving or removing the fuel plate and turning the star wheel. I don't want to grind my plate...I want to be able to put things back to the way they are now if I don't like what I did. I'm not sure how much modified plates are but I'm not willing to spend hundreds to buy one. I guess my options with the plate are moving it forward or removing it and keeping it in the glove box. I understand that the star wheel controls when the turbo kicks in. I've read articles that say turn the top toward the engine to get quicker response but no mention about how much. I read one post where the guy said he turned it something like 25 clicks.
I'd like to rely on everybody's experience with this so I'm not spending weeks trying to dial in this modification. So, I have a couple questions.
Will removing the fuel plate decrease my mileage drastically if I'm just putting around to work at 1200 rpm? or does it only come into play when the pedal is down?
How many clicks on the star wheel to get a quicker response when I mash on it? I'm not looking for pealing rubber...just better.
Guess the bottom line is move or remove the fuel plate?
How many clicks on the star wheel?
I appreciate your advice

I would slide the stock plate forward and leave the starwheel alone until you see how the truck responds. I would spend a little money tho on gov springs there well worth it and will make more difference than the two mods your asking about.

what 94 said. you can do the super basic mods see how you like it. if you want a nice package and that explains the system swell you could get afc live stage 1 or 2, 2 would be good for those moments you wanna roll some coal or have a dramatic performance increase and have it tuned to your liking regularly. they have an outline on all the afc mods, it involves removing the plate so the tuner can control the plate position. and you can tune it all on the fly from in the cab. they also can supply a boost elbow to up your boost a bit to clean up the added fuel. afc live and a 3gsk would be the perfect set up for just a stout stock truck. maybe throw a afe dry bhaf on there and your set at probably a solid 250 wheel horse. maybe more

WPG, thanks for introducing me to the AFC Live Stage. I've done some research on their web site and I'm impressed. I might just go that route.

its a great product for every performance level but i think it would really shine cost and performance wise to the person just looking to upgrade what they have now with the simple mods available on a 12v but now with afc live you can do it from your cab and no need to buy plates or any of that. along with the afc live, the boost elbow and a 3gsk you should have a nice stout truck.

Consider gauges, Boost/EGT. These 215's can get hot pretty quick.

Isspro is the brand I suggest. Ev2 far nicer then your standard autometer, and much nicer to install.

^ 100%

You can also check out hewitt.

Thanks for all the input. I don't want to do all of this at once. I've been shopping ebay for an A-pillar mount and gauges. The one I'm looking at says 98 to 02 and I'm not getting a straight answer from the guy if that'll fit the early 98...or does it matter? It's $260 with gauges, senders and the mount. I figured I'd go with the gauges first so I can see where everything is at now and then when we get closer to warmer weather, I'll spring for the AFC Live.
I'm a little worried about the AFC Live because it's only as good as the person adjusting it and, with infinite settings, there's an infinite chance that I'll screw up the settings somehow. After the AFC, I'll look into the 3gsk and see if I can do it with the pump still on the truck...I don't want to pull the pump again.

You can put the gov spring in the pump with it on the truck.

As for the AFC Live there is really nothing to worry about for messing up settings. It's very east to change and dial in.

Those gauges and pillar mount I'm looking at are made by "Glow Shift". Anybody have an opinion on that brand?

ya you can't just screw up the pump settings really. not with afc live. if its too smokey, turn down the afc control, if it gets too hot up top turn down the full feeling knob, that simple. id suggest going with their level 1 since i doubt you will need the full fuel switch. ass for glow shift stay away. quality gauges are a must and those are not them. get a 3 gauge pod off summit. about 50-80$ and isspro gauges from a ton of different suppliers. they are by far the easiest to install and highest quality. I've ran many autometers and i will never go back.

Thanks WPG...I suspected Auto Shift was garbage. Been looking at some Bank's gauges too.
I've done some research on AFC Live and I'd like the 2. There have been a few times when I want to fumigate those behind me and I think the full fuel switch would come in handy for that.

It certainly would, just keep a close eye on your pyro while doing it.
+1 for Isspro. The quality and service are outstanding, and many of our vendors can give you quotes on a full setup. Many people still swear bt Autometer, but I personally have had lots of problems with them over the years. Also +1 for avoiding Glowshift. Stay away. If all you want are pretty gauges in your truck you can't go wrong with them. But if you need your gauges to be accurate, use them at your own risk.

ISSPRO is the best value. They do stuff for OE suppliers and the military. Good quality stuff and a 3 gauge pillar pack is only about $335

Do it right or do it twice.

Thanks for all the advice. I've got a couple more questions. Regarding the 3gsk, am I correct in assuming that this increases the governed rpm to 3000? I don't plan on running my truck that high so is there any benefit to it? Lets assume that I'm on one of my Alaska trips pulling a heavy trailer at 2000 rpm and I get to a long hill. As I hit the bottom of the hill, I'm going to mash it (without getting up to 3000 rpm) and deal with any downshifts appropriately. Will having a 3gsk improve the hill climbing characteristics over the stock springs? Max torque is at 1600 and max hp is at 2600 so there's no need for me to go to 3000 rpm.
Now a guestion on the AFC Live. I understand that one of the knobs adjusts the maximum fuel and the other adjusts the rate at which the boost kicks in and the switch simply opens it up. Lets say I'm driving to work (7 miles)...pretty much the whole way is 40 mph side roads...just putting along. Am I going to screw up my fuel mileage because I have things set wrong? Or, does the AFC Live only come into play when it's time to work the truck? I drove Semi in my 20's and have a clear understanding on watching and interpreting gauges and have a lot of experience in backing off a bit when the pyrometer was barking with my #10 button. I have a pillar pod and isspro gauges ordered and will run those before I make any changes in order to get a baseline. If the AFC Live only comes into play when the truck is working and I have control over the gauges while it is then I'd be apt to buy it. I don't want the AFC Live to screw up my fuel mileage running to the supermarket. Lower MI is like a pancake (compared to AK) so it's not like I can work the truck to find the sweet spot. There's 3 or 4 times a year when the AFC Live full-on switch would come in handy to deal with some A-holes but other than that, I'd like a bit quicker reaction on the turbo and a bit more power when she's working. I love her the way she is so maybe this is just a bit of a boob lift.

My responses in red

94...thanks for the response and what you're saying makes perfect sense and is what I suspected. Just looking for a little boob job here. I've been doing a lot of research on this site and elsewhere and from what I've got so far is that an 11 plate would suit my needs. I'm not wanting to do studs or springs or exhaust or turbo...etc. I'd like a stock engine in my truck that is happily putting out more hp when I need it without going overboard. I can turn up smoke with my stock setup but maybe it would be better to exchange smoke for a finger!
The slots in the plate are so short I questioned the effectiveness of that movement in affecting performance. I guess the housing is slotted too. Should I slide the plate all the way forward and the housing all the way back?? I think I'll go with the springs and wait till what you say about an 11 plate and the position of the plate and housing or just keeping stock and moving things.

My favorite plate for a tow truck is the 10 that's what I would recommend you going with as well. With these p pumps fuel adjustments are made in mm so while that slot is not very long a few mm makes a noticeable difference in power.

If I were you I would slide your current plate all the way forward (toward the front bumper)and read up on AFC mods since is all free. Just takes a little time to make these tweaks. Doing the washer flip and loosening your star wheel 1 - 1.5 truns would be all you need. Install the AFC housing as it was no need to slide it forward with a stock plate in there.

As I sift through all of this information, my boob job would entail just sliding the plate
forward and seeing how I like it. When I was driving semi, the 10 button was the holy grail and it resided in the mechanics tool box. To the eye you couldn't tell the difference but the indent was different and it made a huge difference. I bought a full set of gauges today and a pillar pod today and will work into adjusting things slowly. I think the fuel plate slide is a good conservative thing to at first. Thanks for all of the advice

I installed my pillar pod yesterday. Pyro, boost and fuel pressure. I had a fuel pressure gauge so I just relocated it into the pod. I installed the Isspro pyro and boost gauges and they all look great. I took the truck for a lap around the block. It's flat here and I didn't have much of a load...just a fuel tank with 100 gallons of gas. Rolling along, I shifted into too high of a gear and mashed it. Pyro read 650, boost read 21 and fuel pressure was in the 25psi range. Is it safe to assume these numbers are in the ball park for a stock truck?
After reading the wealth of information on this site, I have decided to do the following modifications in order to gain some HP, maintain drivability and keep it dependable.

Boost elbow
3 GSK
Slide stock plate forward or new #10 plate (still undecided and need more info) and keep stock position for AFC housing. What plate would you all suggest?

Injectors are stock and have 200k miles on them so I'm guessing injectors are going to be on the list one of these days. P pump was replaced probably 50k miles ago. Should I go with stock injectors? Would there be any benefit to larger injectors being fed by stock delivery valves? I plan on making one modification at a time so I can solve one problem at a time should one arise. Which modification should I do first?

is your pyro pre or post turbo?

I tapped a hole on top of the exhaust manifold 1/4 of the way rearward from the centerline of the collector leading to the turbo.

Those readings are, IMO, very healthy for a stock 12V. Both the manual and automatic '98 12V have excellent p-pumps, with perfectly adequate DVs for way more power than you intend to make. Personally- with regards to your original post, if I were you (now that you have gauges) I would pull the plate out and slide the AFC housing full forward, and tool around in it for a few days so that you can get an idea what kind of power, smoke and throttle response (and economy, if you can be disciplined enough for an accurate observation) your excellent pump can give you when you run it more or less "wide open" without other mods. I think you will be impressed.
Then, with that experience in your knowledgebank, I would just add an AFC Live unit and play with it until you're happy. A GSK is a fantastic mod, a fuel plate is a fantastic mod, the Mack plug for rack travel is a fantastic mod, and- if you didn't have a '98- DVs would be a fantastic mod. Hell, anything that 94 12V tells you should be taken to heart, I respect his opinion in my top 3 for members of this site. But getting back to your original post, I think you should just go AFC Live and be done with it. It will accomplish all the same things (excepting the GSK) with absolutely painless convenience of adjustability. You may still want to add a GSK, bump timing, etc at some point, but for your purposes I think you would be well served with just the AFC Live. And unless you're going to change turbos, I don't necessarily think that injectors are a good investment unless someone qualified informs you that there's something wrong with yours. Even at 200K, there probably isn't. If you're making 21psi with a stock pump and it runs smooth, I wouldn't worry about them today; and "upgraded" ones are only going to give you more fuel that you won't necessarily need most of the time- which generates more EGT with little advantage in your schenareo. Granted, if you spend enough on them they can be far more efficient... on paper. But I doubt the seat of your pants will think the investment was justified with the stock turbo, head, etc.

at 200k injectors are going to be tired. They may still work fine, but a new set will have benefits.

A new set didn't give me any benefits at 100K beyond that.
A bigger set did, but that went with the ported head and bigger turbo.
If your truck isn't running well, there are ways to determine if the problem is injectors. In which case, new ones will change everything. If it is running well, the only reason to change injectors is because someone who sells injectors talked you into it and you want to tell your friends you did it.

My truck is running fine and I don't want to fix something that's not broken. When I drove semi we'd get over 100k a year...and we went through some injectors. I lived in mountain country and the trucks worked pretty hard. When we would report excessive or unusual smoking or rough running, the mechanic would, a lot of times, find it was the injectors. Not sure our engines would present the same way with failing injectors.
My truck is fine. What I'd like is quicker response on the throttle (if that's possible) which I think is at a stock setting now. From what I've been reading, I can accomplish this by loosening the star wheel a little bit. I'd like more power pulling hills with an enclosed car trailer going to Alaska once a year. From what I've read, I can accomplish that with either sliding my plate or buying a 10 plate. Lastly, and least importantly, I wanted some smoke to be available at the pedal when I wanted it. I can get some of that now by going into a higher gear and mashing. It clears up pretty quick. I'd like a tad bit more smoke when there's an A-hole behind me.
After hours of research here and reading all of the very helpful responses, I'm going to slide my plate forward, keep the afc housing where it is, get a boost elbow and turn the starwheel loose 5 clicks. I'll see how I like that and either leave it alone or bite off a little more. I'm sorry...I'm a bit conservative with my truck. I may not be in the right group but I guarantee that you all have educated me and I really appreciate that!!

Well, when it comes to throttle response, there's really no replacement for a GSK. But I'd still pull the plate and slide the AFC all the way forward and run it wide open first. You can always back it off, and at least you'll know what you have to work with.

JBear...GSK isn't off the table and it sounds like a great improvement. Dumb question here...from what I've been reading, it sounds like there's some sort of nut at the top of the spring retainer (I guess it clicks) that needs to be set to exactly what the original springs were set at. That's fine, I've got the tools to do that. In looking at the cutaway, it looks like that nut would take a specialized screwdriver...almost like a forked screwdriver. Is that the case? I was doing some shopping for GSK's last night...is there a brand that has been proven dependable and reliable?
Last weekend, after I got my gauges installed, I decided to do a full run-up on the engine and let the governor take control. I've never done that...not even in the semi's I've driven. It went up to 2900 and was fluxuating a bit. I can see where a GSK would help. I don't want to dig into the thing and find out I need some sort of special tool to do the job though. I want the tools I need ahead of time.

No special tools needed for that job, I have done many with just a normal flat head screw driver. It is easier if you get a wide and fairly long flat head and cut a slot in the middle. A flat head with a magnetic tip is the best choice.

Pack brake makes a good kit have not had any issues with them and they set up nice.

It's a good idea to draw yourself a picture while you're doing it too, for orientation. I'm not explaining this right. Um.

Just wanted to say thanks for this thread. I have a stock 95 that I want to mildly tweak too.
Brian

:tu:

I found some Pack Brake 3GSK springs on ebay. I'm going to order those today and install those first. Once I'm sure that installation was successful and it's still running good, I'll take the next step. I just emailed the guys at Power Driven Diesel some questions I have about their AFC Live setup. I'm looking at their AFC Live 2 and max travel kit. The installation instructions say to disconnect the wastegate but they also offer a boost elbow. I don't know if there's a possibility of over boosting once I have the AFC Live adjusted for proper EGT. I'd like to be able to have things balanced where I can trudge up a hill with my foot on the floor and have the pyro temps and boost within safe limits.

IMO I would never plug the wastegate

Agreed, there's just no reason to. Open the pump, you'll make the boost, even with a stock turbo.

94 and JBear. I agree, I think my stock turbo can make more boost than what the wastegate is allowing. Since I got my gauges, I was able to get the boost up to 21psi. It's a stock truck and this reading was on a flat road. I guess I screwed up with my question. If I get the AFC Live2 and disconnect the wastegate as suggested, is there a threat that I can over boost with a stock turbo when I'm working the truck? With the Live, I can dial in the pyrometer to safe limits and expect the boost to be in the safe range for a stock truck. If I dial in the AFC live to get boost up to an acceptable limit, will I be blowing the EGT? I know...I know...it's all about my foot. Boost and fuel make power and I don't want to spend money to dump the fuel only to be limited by the boost. I'm thinking the AFC Live and a boost elbow to limit pressures. What do you think>

Yes even with the afc live you can still overspin the stock turbo with the gate blocked off.

I think it's going to be a question of usage for you. Lots of people say not to spin the stock turbo more than 35psi. I ran mine for nearly 100K hitting 40psi regularly, and when I upgraded my turbo the original was still nice and tight. Since I was running my pump wide open, if it was going to make more boost it would have. I never blocked any waste gates or used a boost elbow. That all having been said, I wasn't driving around making 40psi all the time. I very seldom went over 30psi, actually. Just a few times a day, depending on what and where I was towing. If you are going to drive it like a bat out of hell 100% of the time, you may compromise it's life expectancy a bit; but if you're going to drive it like a normal person and only get into it now and then, they're surprisingly robust.