super charger questions

[Bazowak]

I personally like the E and F cams. I've had very good results with the F cams in the past. It provides the idle quality I think your looking for as well.

As for a blow through type carb I hope your good with tuning because from what I know about them they can be very finicky (technical term there) and require frequent adjustment. You would be money ahead to get a wide band A/F meter to help with tuning issues and you will also need a boost reference fuel pressure regulator and for that matter a fuel system that is up to the task of providing the need fuel.

Something like -8 supply and return lines, a good high flow GPH fuel pump. It never hurts to over engineer a fuel system. There are many things to consider when running forced induction with both EFI and carb. set-ups.

Of course the other issues that you might want to consider would be the rest of your running gear....clutch, that T-5 trans, and the 7.5 inch RE if that is what you still have. With the charger you would normally expect I would think a 15 to 20% increase in HP as a min. and I don't think that your stock T-5 would hold the additional torque, if it did then you would really need to worry about the stock Ranger RE.

I would start be building the truck around the charger. When all the needed upgrades are done then put the charger on. You'll be much happier with it than always trying to fix something that the extra horsepower breaks. Breaking stuff is cool if you read Car Craft which I do but can also lead to many nights of frustration, P-O'd wives, which can also sometimes lead to a for sale sign.

This is just my way of looking at things and of course I can spend other peoples money. Do yourself a favor and eliminate the frustrating nights and angered wife/girlfriend who think you love your truck more anyway. Prepare the truck for future upgrades, then make the up grade.

[v8ranger]

very good advice Bazowak. My wife is cool tho, She came to grips with the fact that my truck will never be done. I think I will start with a 347 and go from there. I dont know. So many opptions so little money lol.

[prpleranger]

jegs has demon blowthrough carbs for around 584.99 was lookin earlier when i was thinking about turboing my 5.0

http://www.jegs.com/webapp/wcs/stores/s ... -5282010bt

[v8ranger]

Would I have to do any sort of ignition stuff or will my HEI work ok with the super charger? and what about the timing? would I have to set that lower? Also what about PSI, what is the max that my motor and set will take without blowing it up? 5.0HO GT-40 heads large tube shorty headers and air gap 4brl.

[cgrey8]

I have no clue how timing is dealt with in carbed systems, but in injected systems, you have to pull spark as boost increases. The higher the boost gets, the faster the fuel wants to combust naturally. So you require less and less advance. And that's just under ideal conditions.

With heavily boosted engines or engines that don't have intercoolers to help maintain the air temps, you also pull spark and increase enrichment as the air-charge temp increases. The natural tendency of superchargers is to heat the air. That's inevitable. However if the air gets heated too much, then it will cause predetonation in the chamber. Just the act of the piston compressing hot air will cause the fuel to combust before the spark fires...the dieseling effect. And to add insult to injury, if your engine is run too rich all the time (as carbs often do), you are surely going to have carbon buildup in the cylinder which will cause predetonation to be even more pronounced. To prevent that in injected systems, the tune is setup to over-enrich the mix when ACT temps rise above a certain point. Fuel being sprayed into the hot air literally cools the air as the fuel evaporates, so when the air is "too hot", you simply spray more than you need for temp control which ultimately gives you detonation control and a lower combustion temp. On heavily boosted engines, particularly those without intercoolers, this is a must to keep the engine from blowing head gaskets and melting pistons.

I have no clue how those dynamic conditions that are easily maintained via computer are handled in a purely mechanical world.

[prpleranger]

Msd has a boost retard controller that works inline with ignition

[MalcolmV8]

Following up on what Chris said about boost temps and the ACT causing the computer to pull timing is a very real issue. I ended up grading the supercharger's intercooler to keep ACTs down and reduce the frequency of the computer pulling timing to save from detonation. So while this mod doesn't really make more power it does reduce the computer from pulling timing and lowering power.

The black smaller unit was the stock intercooler and the silver one is the after market unit I installed. This is the part that sits in the lower from bumper and has the super charger coolant flowing through it.





And in case you curious here's what the part that sits under the supercharger itself looks like


And here's the spot in the motor where it sits below the supercharger


Malcolm

[v8ranger]

Thanks for that good info. What whould be a safe boots range to stay in?? I am just trying to gather all the info I need so I know what parts I will need to do this when Im ready.

[cgrey8]

Putting boost on a stock engine on-the-cheap for EFI is limited to about 6PSI. Most any stock engine can handle up to 5-6 PSI of boost while reusing most of the stock equipment. For instance, there's this device called a Fuel Management Unit (FMU) that replaces your Fuel Pressure Regulator (FPR).

A normal FPR maintains a constant differential pressure across the injectors so regardless of what the pressure in the manifold is, the injectors will flow the same amount of fuel. So for instance, if you boost the intake by 5 PSI, then the FPR will raise the pressure in the fuel lines by 5 PSI. If the intake has a 5 PSI vacuum in it, then the FPR will lower the fuel line pressure by 5 PSI. It's a 1-to-1 ratio and in stock form, most Ford FPRs will try to maintain a 39PSI differential pressure across the injectors.

FMUs on the other hand vary the amount of pressure on the injectors by increasing the pressure on the injectors during boost by a factor more than the amount the booster is pressurizing the intake. So if you have a 1.6 multiplier FMU, and you boost the intake with 5PSI, then the FMU will increase the fuel line pressure by 5 * 1.6 or by 8 PSI. But it only does this during boost. At vacuum, it acts just like a normal FMU. What this does is makes the injectors "act" larger than they really are during boosted conditions to over-enrich the mix beyond what would normally get delivered particularly when the stock injectors are technically too small to deliver the amount of fuel required to satisfy the added amount of air being shoved down the engine's throat. An FMU is a cheap and very inexact way of getting boost enrichment on a stock or near-stock engine without the cost of replacing injectors and tuning the EEC. For optimal performance, you'll need a larger MAF sensor, larger injectors, and the EEC tweaked to "support" boosted conditions correctly and pull the right amount of spark during the boosted conditions...all of which can be done with Do-It-Yourself (DIY) tuning equipment like a TwEECer, but that's EFI and generally EFI is considerably more expensive than carb setups. Not to mention if you are going to tackle doing engine tuning, there's a fair bit of a learning curve associated with DIY tuning. It's not rocket science, but when you 1st look at the software used to tune an EEC and start reading up on DIY tuning, it sure feels kin to rocket science. But once you get familiar with how the EEC does what it does, it eventually comes into focus if you stick with it and you quickly realize the higher level of accuracy in electronic engine management that just can't be had in mechanical systems. Add to that, the guys over on the EECTuning.org forum are just as helpful as the guys here. As long as you are courteous and aren't demanding, they help as much as they can to get your questions answered and get you moving forward.

As it relates to carbed setups, I'm just not sure. But my gut feeling is there are similar "on-the-cheap" ways of getting boost for carbs that are not optimal as well as ways to do it right that cost considerably more. It sounds like this thread has drawn out some of those details here.

[MalcolmV8]

Chris, you mentioned getting the stock ECC modified to support boosted applications. How do they do that? Can you feed it additional sensors? So it becomes aware of manifold pressure, how about fuel pressure? and while not directly related it would be very nice to add a knock sensor. I know it would have saved my motor.

[cgrey8]

The 89-95 Mustang EECs are not setup to support boost by default, but they can be. The main thing that has to be disabled in the 89-93 Mustang EECs is the WOT functions. The WOT functions are a pass-over from the Speed-Density days and they make tuning for WOT easier. But they don't lend themselves to superchargers well because they do not allow for Fuel and Spark adjustment based on Load. They are 100% RPM Based. For those that don't know, Load is another word for Instantaneous Volumetric Efficiency which is just a fancy way of describing the amount of air that is getting into the engine as compared to the CID, which is the theoretical MAX at atmospheric pressure. With a boosted application, your Load goes well above 100% and with heavy boost, it can get into the 150-180% range...and in some cases even further. Well, it's safe to say that the spark you'd want to command at 75% Load is not the same as what you'd want to command at 130% or 150% Load.

Starting in 94, the EEC code abandoned the WOT functions because of this limitation and in fact don't even contain the code to activate the WOT functions if you wanted to. Instead, what they do is control Fuel and Spark purely out of the Fuel and Spark tables which are RPM and Load Based.

Once you configure the EEC to abandon the WOT functions and instead stay in the Fuel And Spark tables, then you need to rescale those tables.
Even in the 94-95 Mustang EECs, those tables only define Load up to about 75% because a stock engine doesn't get much above about 80% Load. What that means is any condition above 75% will command the same values for Fuel and Spark as you'd get at 75%...again not good. So for boosted applications, the tables must be retasked to allow the tables to continue to make fuel and spark adjustments above 75% Load. This is called rescaling the tables. If you run 10 PSI of boost, you may need to rescale the tables to allow adjustment of spark and fuel up to say 125% Load. 15 PSI applications, you may need to rescale for up to 150% Load. After you do this, you now can more gradually pull spark from non-boost conditions as boost increases to Max. With Positive Displacement boosters, it's almost an all-or-nothing condition. But with centrifugal boosters, the boost can be applied to the engine quite gradually and thus being able to gradually pull spark from 75% to 120% could mean a good bit more torque at the 90-110% range where you aren't quite at WOT, but are getting enough pull and don't need to be at WOT (i.e. passing someone on the road).

The downside is you only have so many rows in the table to work with. Retasking them means there's less resolution. So where you might have had 8 rows defined as 5%, 10%, 20%, 30%, 40%, 50%, 60%, and 75% loads. You'll have to sacrifice some of those values to make room for the Load to go higher. So after rescaling, you may have 10%, 30%, 50%, 70%, 90%, 110%, 130%, 150%. The transitions between each of these rows is not always linear in the stock setting. But when the EEC is rescaled, you are forced to make the spark applied linear between the rows that are now "wider". The good news is most people don't find this as a significant limitation. At non-WOT conditions, you don't have to be dead-on a value...just close. And you can get it close.

Does that make sense? I know I said A LOT. I just hope I didn't assume too much knowledge. I'm used to posting these type explanations over on the EECTuning.org forum where people have worked with the software at least some. People on this forum I doubt have ever heard of programs like BinaryEditor or EEC Analyzer to be familiar with some of these concepts. So I hope this all isn't just greek.

[87ranger]

one more reason to buy a stand alone holley standalone plug in 5.0 system, its already setup for you

[cgrey8]

I won't lie and say the aftermarket EECs are a waste of money. They are not. Most of the time, they vastly simplify the tuning experience by breaking it all down to only the important pieces and eliminate all the other crap that nobody cares about.

The Ford EEC code is convoluted and the way the tunes work is often confusing because Ford had to do more than just make the engine run right. They have to meet all sorts of emission requirements, longevity requirements, tune for all sorts of different potential climate conditions, and meet certain fuel economy targets. Add to that, the code they use in the EEC is the result of ongoing development that spans back to the beginning of the Ford EEC. Like I said, there are parts of the code that are obvious "left overs" from the Speed Density days. This is just my suspicion, but it seems there were multiple depts in Ford responsible for the different parts of the code. And sometimes they cancel out their efforts. For instance one dept may dictate a certain amount of fuel enrichment during cold startup. Then another dept likely found those values were causing problems, but weren't allowed to change the values, so they just cancelled those values out in the Base Open Loop Fuel table.

There's no doubt, the options and code is far more complicated than it needs to be to tune an engine for our purposes...and the "extra" doesn't always make things better...just more complicated and confusing. From the consumer's standpoint, you can't deny the financial benefit to reusing the stock EEC. You can retune these popular Ford EECs via very affordable Moates or SCT chips. And if you need datalogging (most people do), the TwEECer RT can do that too for a bit more. And once you got a tune working in the TwEECer, you can burn that tune to a Moates chip and sell the TwEECer off. The resale value of the TwEECer is quite solid. There are plenty of people that bought their TwEECer used for $450, tuned their vehicle for a year, burned that tune to a Moates chip for ~$60 for the Moates chip. Then sold their TwEECer for how much they paid for it. For someone that already has a Ford EEC, buying the equipment and software needed to tune it is often far cheaper than an aftermarket system. For someone that doesn't mind the added complexity to save a grand or two, it's a good option to have available. But for those that can afford the luxury of an aftermarket engine management system will get a much more straight-forward tuning experience.

For those interested in the TwEECer, read over this thread 1st:
Things to know BEFORE buying a TwEECer

[Bazowak]

I just thought I might add to this thread. I think you may have mentioned something about being "old school" and going with a carb set-up. I think I also read something about timing and such.

Something to consider would be to look into some MSD products. They have the 6BTM ignition control which has a boost reference port that will pull timing as boost increases. For this set-up though you have to run an MSD distributor as well. That would help with your timing issues. I think also as boost goes up you have to run a cooler range of spark plug too. One to two ranges coolers depending on boost level.

I think I also remember you asking about fuel requirements. The last Ranger I built had a 15 Gal fuel cell in the bed with -8 AN supply and return lines. I thought at one point I would upgrade to forced induction so I also got a boost/vacuum reference fuel pressure regulator from Mallory that was a 3 port design with a return. This regulator also has a boost reference port so that when boost increases so does the fuel pressure. I ran a aeromotive 220gph pump and a high flow fuel filter as well.

To help keep costs down I also used the summit brand parts. Pretty much the same as name brands but w/o the fancy box and cool stickers. I know they have a whole new line of ignition controls and the also have socketless hose ends and the socketless hose to go with it. I was always very happy with the fit and finish of the summint parts too.

Hope this helps some and have a look at some the summit racing parts as they can help to save some coin.

[Bazowak]

Just for GeeWhiz I found the part number for the MSD 6-BTM. I goes under PN MSD-6462. It's a bit pricey for starters but if it saves an engine from detonating itself to death then it's money well spent. Check out summit to find it.