I've lost my mind.. or an MP90 on a 4.6L

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SilverXJ
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

I've been working on the drawings for the output and input ports. I started with the technical drawings provided by Magnuson. I then laid the forms out in Illustrator and then printed them out. The bolt holes lined up well, but the general form was a bit off. I did a dry rubbing then scanned them in. From there I brought the images into illustrator and modified the forms.
Image
The red is the modified form. The output adapter plate will have bolts around the passenger side, from and rear to secure it to the modified intake. The driver's side will get studs and hand over the intake's plate. I have not yet added drill points for the throttle body's bolts, but the throttle body port seen (red) is 70mm. I have yet to decide on placement of the vacuum ports nor the port for the water/meth injection on the intake plate yet.

I have purchased a 00+ intake manifold complete with throttle body and fuel rail. The TB and fuel rail will be for mock up.

Up next is cutting an inspection hole in the intake manifold to see what else i may need to modify and decide on how much to cut off. I will also cut mock up forms on the router for the intake and output ports for the SC.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

I got some work done today. I cut a hole in the manifold to get a better look what I am dealing with.
Image

Doing the angle cut will interfere with the 3&4 cylinder's runners. I have a rough line drawn about where the cut will land. It also shows the structures for the runners. I will be reducing the runner to open it up more. I don't think that will be that great of an issue as the other SC manifolds as well as the pre 2000 manifolds had a great difference in the intake runner length as the log portion of the manifolds is part of the runner length.
Image

This is the currently intended cut.
Image


I am considering having a box welded on the underside to increase plenum volume since I will be taking so much away. Also, I will be putting 1/2" strips under where the bolts will land. I don't like the idea of running a bolt into 3/8" aluminum only. They strips will be held in by aluminum body panel adhesive or JB weld. I need to look up the technical specs of each to see what kind of heat they can hold up to. With the 1/2" strips and the 3/8" aluminum plate I may be able to use fredserts instead of tapping into the bare aluminum. http://www.fredsert.com/fred2/index.html. If I still don't have enough depth I may just bolt into the aluminum and at a later time, if necessary, use keenserts as suggested by o-gauge. I also haven't looked into the cost of fredserts, but I fear I may get sticker shock from the serts and tooling costs. The word "milspec" comes at a high cost.

On the vacuum ports the brake booster will get its own port as will the PCV line. For the three vacuum lines on the side of the manifold (emissions, and cruise, etc) I am thinking about doing a distribution block with a single large line coming off the back of the SC.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by JolleyRoger »

SilverXJ wrote:The word "milspec" comes at a high cost.
Not only that, but, anything associated with General Dynamics is overpriced...

Although those Fredserts are beautiful little pieces.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

Ohh... I didn't notice the General Dynamics part until you mentioned it.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by 92tank »

how will you make vac in the manifold if you have boost? you might have to look into a vac pump like the turbo deisel trucks have
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

The same way every other gas engine gets it. Pre supercharger.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

I'm 90% sure I will be going with water/meth injection right off the bat. I have a feeling that with my compression ratio I might need it just to prevent ping and keep the timing up. I figure that I could do a safe tune on the FIC first, then do a tune with the water/meth. Use the safe tune as map 2 and the w/m tune as map 1. Use the output from the washer fluid reservoir low fluid switch to tie into the FIC and switch between tunes.

I'll be removing my CPS modification as I don't want to dial back that much timing on the FIC. It adds 6* base.

I'm still working on the logistic of the power steering pump. I know that I can buy one from PSC, but I don't want to spend that much and I really don't need an upgraded pump. Autozone does offer a seal kit, so tapping it myself is a possibility. But if I take it apart its probably a good idea to rebuild it as well, which I haven't seen a kit for.

Hopefully soon I will have the adapter plates mocked up. Still need to order counter sunk bolts and see if TRD has inlet and outlet gaskets for this thing, or find material myself and cut them on the laser, or just use RTV.

Something I have been thinking about is using a push style solenoid instead of a vacuum actuator to control the bypass valve. When there is no power to the solenoid it will put the valve in the open position, bypassing boost. The FIC has a 12 volt output that can be configured based on TPS position, MAP load, RPM or any combination. Probably not necessary but I would be able to control when full boost comes on, but I don't think the bypass valve is large enough to bypass all the boost....

For the bypass valve I will probably need to move it to the passenger side. It currently on the drive side and may interfere with possibly the brake master cylinder and its lines. Magnuson could sell me the vacuum actuator, linkage, etc. They refused to sell me the bearings for the rod though. They wanted me to ship it to them and have them change the location. Shipping would have been high both ways for that. Then I remembered that most bearings had part numbers on them. Took a look and found them. So when I get to that stage I can remove and install them myself and just get what linkage is necessary.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by CobraMarty »

If you are not 'pinging' now with the CPS mod, I would leave it in so it will run great, as it does now, when not in boost and then just dial back the timing with the AEM when in boost. When in boost you can dial in 1-1.5*/pound boost retard. With the water inj. you'll be fine.
I am ready to take what little timing retard I have out. I have no detonation. I want to have more timing advance when not in boost which is like 90+% of the time, and just dial back the timing when in boost.

The washer fluid reservoir low fluid switch is not a on-off switch, or at least mine isn't, it is a resistance change type of switch. You might be able to tap off the low fluid light wire and directly or thru a solenoid to the AEM map switching wire. That is an elegant and complicated setup. Why not just, when the low fluid light comes on, you are not out of fluid at that time just yet, try and stay out of boost and stop at the nearest gas station (washer fluid $1.99/gal) or use the gallon jug you have/keep in the back of the jeep to refill the washer bottle.

The vacuum actuator actually works surprisingly very well. I thought of using a 12v solenoid way back and decided against it. No need.

With your manifold angle cut for the flange, Will you have to open up the intake runner walls especially for 3+4 cylinders on the inside of the manifold?
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

CobraMarty wrote:If you are not 'pinging' now with the CPS mod, I would leave it in so it will run great, as it does now, when not in boost and then just dial back the timing with the AEM when in boost.
I'm not fond of pulling a lot of timing out with the AEM as it will also be changing the injector firing as well, however it isn't that critical up at higher RPMs. And I am unsure the PCM would be happy with the cam sensor was seen moving different form the CPS.
The washer fluid reservoir low fluid switch is not a on-off switch, or at least mine isn't, it is a resistance change type of switch. You might be able to tap off the low fluid light wire and directly or thru a solenoid to the AEM map switching wire.
The FSM indicates its a switch both in the wiring diagram and the text
When the fluid level in the reservoir falls below the pivoting float on the sensor, the float changes position and closes the internal switch contacts of the sensor.
But the FSM has been wrong before.
That is an elegant and complicated setup. Why not just, when the low fluid light comes on, you are not out of fluid at that time just yet, try and stay out of boost and stop at the nearest gas station (washer fluid $1.99/gal) or use the gallon jug you have/keep in the back of the jeep to refill the washer bottle.
Not complicated at all, if the level indicator is an open/closed switch. I see no reason why they would have used a potentiometer type switch in it instead of just an open closed switch. I could try to stay out of boost when the light comes on, but that is not an elegant solution. This way I won't have to worry much either.
The vacuum actuator actually works surprisingly very well. I thought of using a 12v solenoid way back and decided against it. No need.
I don't doubt it does, but it would give me greater control over boost and can be tied into the second map function and the washer level switch. That is assuming that that feature does change with the map and doesn't stay constant. I'll probably go with the vacuum actuator for now then possibly play with a solenoid later.
With your manifold angle cut for the flange, Will you have to open up the intake runner walls especially for 3+4 cylinders on the inside of the manifold?
Yes, but I am not concerned with it that that much. It will just resemble the earlier log style manifold and other supercharger log style manifolds for this engine. You can see in the pic where the new top will fall and the runner extensions that will have to be modified. I will probably modify the walls of all of them to reduce their lengths all together to at least try to keep them closer.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by CobraMarty »

SilverXJ wrote:I'm not fond of pulling a lot of timing out with the AEM as it will also be changing the injector firing as well, however it isn't that critical up at higher RPMs. And I am unsure the PCM would be happy with the cam sensor was seen moving different form the CPS.
Doesn't the AEM move the cam sensor and CPS together so they don't 'mismatch'?
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

Yes, but that will change the injector firing as well. And i don't know what the PCM would do if you disconnected the CAM sensor from the equation so it isn't moving the injector firing.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by CobraMarty »

Our low tech engines are not sequential injection? or are they?
Does the injection timing really make much difference. Many EFI engine injectors are batch fired.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

It is sequential. It makes most difference at idle and low RPMs.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by MrNoBody »

In my opinion, I think with the small amount of boost you are planning to run, I would pull the head(and I know you probably hate to hear this given the amount of time/effort/money you've vested) and open the combustion chambers to bring your static compression down to 8.5 and/or retard your valve timing to bring the dynamic compression down too. Doing this will eliminate the need for water injection and ignition timing retard, both of which will take away horsepower. For every degree of ignition timing you retard you will loose between 1.5 and 2.5 hp; where 6psi=9to12degrees=13-30hp plus water injection approximately 5-10hp(off the top of my head as I've not performed any arithmetic to support this assumption) for a total loss of 18-40hp and this is in addition to the pumping loss for running the supercharger(how many hp required for mp90 to pressurize to 6psi). How much total HP do you think 6psi is going add?

Additionally, while I applaud your ingenuity with regard to all work I have reviewed that you have put forth, I would rebuild that intake manifold plenum in its entirety since you will undoubtedly be welding it anyway as doing so would provide you more options with mounting mp90. I would make all intake runners the same length, tuned for 4th wave-set at max boost rpm, with less than 10% taper, and a plenum approximately 40% the cylinder volume.

Lastly, the camshaft position sensor is nothing more than a signal generator that works in conjunction with the crankshaft position sensor to let the pcm know which injector to fire and at what crankshaft angle just as intake valve begins to open. If you built a signal generator to operate off the crankshaft position sensor you could eliminate the camshaft position sensor as long as your generator fed the pcm. Why go thru that when you could rotate distributor slightly. I would etch single degree marks into distributor base where it mated to block to adjust fuel injector timing. Why do you need to adjust injector timing? If you were just curious about the crank-angle in relation to injector firing; pull spark plugs, put degree wheel on crank, put a pointer in some available space, adjust to 0(TDC on compression stroke), attach led to injector #1 wiring and mount at degree wheel pointer, while cranking motor you should be able to see the crank-angle-injector-timing. You could compare this with your camshaft spec card.
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Re: I've lost my mind.. or an MP90 on a 4.6L

Post by SilverXJ »

MrNoBody wrote:In my opinion, I think with the small amount of boost you are planning to run, I would pull the head(and I know you probably hate to hear this given the amount of time/effort/money you've vested) and open the combustion chambers to bring your static compression down to 8.5 and/or retard your valve timing to bring the dynamic compression down too. Doing this will eliminate the need for water injection and ignition timing retard, both of which will take away horsepower. For every degree of ignition timing you retard you will loose between 1.5 and 2.5 hp; where 6psi=9to12degrees=13-30hp plus water injection approximately 5-10hp(off the top of my head as I've not performed any arithmetic to support this assumption) for a total loss of 18-40hp and this is in addition to the pumping loss for running the supercharger(how many hp required for mp90 to pressurize to 6psi). How much total HP do you think 6psi is going add?
No, I won't be messing with the head now. I have no reason to run anything higher than 6psi. 6psi should put me around 325 hp. Its a safe amount and won't grenade the engine. The engine wasn't designed with boost in mind and I'm going to see if it can be done.
Additionally, while I applaud your ingenuity with regard to all work I have reviewed that you have put forth, I would rebuild that intake manifold plenum in its entirety since you will undoubtedly be welding it anyway as doing so would provide you more options with mounting mp90. I would make all intake runners the same length, tuned for 4th wave-set at max boost rpm, with less than 10% taper, and a plenum approximately 40% the cylinder volume.
Because I have $2000 to pay someone to do that. Care to donate? I could also add an inter cooler at the same time for an extra $1000. And I would have a very nice $3000 manifold to run 6psi boost on something that is worth maybe $6000. Not to mention lack of room in the engine bay to make the intake runners truly the same length. lol.
Why do you need to adjust injector timing? If you were just curious about the crank-angle in relation to injector firing; pull spark plugs, put degree wheel on crank, put a pointer in some available space, adjust to 0(TDC on compression stroke), attach led to injector #1 wiring and mount at degree wheel pointer, while cranking motor you should be able to see the crank-angle-injector-timing. You could compare this with your camshaft spec card.
This has already been done. I know when the stock PCM fires the injector. Search on here. The cam sensor signal needs to be retarded with CPS so the PCM doesn't make noise. It doesn't like it when the two signals don't stay with each other.
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