Milling Magnum heads

Posted By: 1976Fury

Milling Magnum heads - 08/14/12 09:48 PM

How much shaving can a guy get away with on these? I want to build a nasty 360sb and want to put a set of magnum heads on the motor. Id like to go with the magnums because i can also use the manifold off a dodge pickup w/t the injection setup. Bad idea? If so someone steer me right. Thanks in advance

Posted By: DaytonaTurbo

Re: Milling Magnum heads - 08/14/12 10:05 PM

No clue on shaving the magnum heads. How much power are you aiming for? That will dictate whether using the stock intake and factory efi controller is a good idea or not.

Posted By: BulletBob

Re: Milling Magnum heads - 08/15/12 06:18 AM

Quote:

No clue on shaving the magnum heads. How much power are you aiming for? That will dictate whether using the stock intake and factory efi controller is a good idea or not.

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/15/12 11:57 AM

if he's going to run NA, he can build quite a nasty little engine and use the stock EFI system.

Go to the race section and check out Adobedude's set-up. He's racing a Dakota into the low 12s, and might have even dipped into the 11s by now. And his race track typically has 10k foot Density Altitudes!

There's a lot of 408 stroker motors with serious cam specs that are tuned with SCT utilizing the stock fuel injection system. --SCT over-writes portions of the factory PCM to adjust fuel delivery tables, spark timing, etc. and can program the computer to run in open loop all the time, or retain closed loop for part throttle cruise.

but when you start talking about boost, you start to run into the limit with the factory stuff. some guys have done mild builds on boost, swapped to a 2-bar map sensor, and had good luck, but if you really crank up the boost, you'll need to look at megasquirt or the like.

Now, as to the original question, how much can you shave the heads? I dunno. Mine are cut .030, and I'm using a Felpro 1008 head gasket which is about .015" thinner than the factory gasket. This bumped my compression from the factory 9.0:1 to about 9.5:1 while still retaining the stock dished pistons.

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/15/12 12:16 PM

I just verified...his best now is 11.77 1/4 mile E.T. @ 8400' DA.

so how radical do you wanna go? (I mean...there IS a limit to using the factory stuff, but it's WAY up there!)

Posted By: 360view

Re: Milling Magnum heads - 08/15/12 01:41 PM

I think I remember reading that the
aluminum Magnum heads
had an extra thick deck and could stand 0.060 inch of milling, but i dont remember seeing anything about the stock cast iron Magnum cyl heads.

Here's a few links that are worth a look:

http://www.hotrod.com/techarticles/engin...ge/viewall.html

http://www.moparmusclemagazine.com/techa...ck/viewall.html

http://www.popularhotrodding.com/tech/0507phr_mopar_magnum_engine_specs/

Posted By: DaytonaTurbo

Re: Milling Magnum heads - 08/15/12 05:26 PM

Quote:

if he's going to run NA, he can build quite a nasty little engine and use the stock EFI system.

Yes, if for (1) he wants to live at the mercy of what, the one guy who does the retunes for the SCT tuned OBD2 mopars? And for (2) if he wants to go through the work of swapping in all the OBD2 wiring, assuming he's not building a 90's truck. The SCT tuner with a custom tune for an aftermarket cam "only" costs what, 400 bucks?

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/15/12 08:47 PM

Quote:

Quote:

if he's going to run NA, he can build quite a nasty little engine and use the stock EFI system.

Yes, if for (1) he wants to live at the mercy of what, the one guy who does the retunes for the SCT tuned OBD2 mopars? And for (2) if he wants to go through the work of swapping in all the OBD2 wiring, assuming he's not building a 90's truck. The SCT tuner with a custom tune for an aftermarket cam "only" costs what, 400 bucks?

I know of 3 guys writting the tunes for them if you want someone who has experience with the SCT program. Or you can buy the SCT PRP package, and write your own tunes after you learn the software.

you can get the hand held tuner and unlimited tunes where, if you make mods to the engine later, or even swap a whole new engine into the vehicle, new programs for those mods/engine are free. that costs $360.

Or, you can go without the unlimited option, and save some money.

..but the guy I bought my unlimited tunes from...has the best customer service I've ever seen. send him an email at 9 pm on a saturday night, asking to tweak something minor, say, coast down fuel shutoff, and by 5 am on Sunday morning, I have a new program in my email, waiting for me to put it on the tuner and load it into the truck.

you can knock SCT all you want, but when tuning EFI small blocks, it's rather difficult to find a cheaper, better solution.

but you're right, ASSUMING it's already an OBD-II system. If it's OBD-I it may be cheaper in the long run to go with FAST, Megasquirt, etc. instead of the cost and hassle of converting to OBD-II, and then getting SCT.

Posted By: DaytonaTurbo

Re: Milling Magnum heads - 08/15/12 09:18 PM

My issue is I don't want to live the mercy of having my tune rely on some guy on the other end of an email. How is he supposed to be able to properly tune a unique combo without real time feedback? I'm just not a fan of this one size fits all type tuning. I've played with a program before for retuning stock type ecus. It's doable but very overcomplicated compared to an aftermarket system that's designed for this kind of thing. If the vehicle the OP is building the magnum for is not a 90's OBD-2 truck, I wouldn't bother with the stock electronics.

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/15/12 11:25 PM

Quote:

My issue is I don't want to live the mercy of having my tune rely on some guy on the other end of an email. How is he supposed to be able to properly tune a unique combo without real time feedback? I'm just not a fan of this one size fits all type tuning. I've played with a program before for retuning stock type ecus. It's doable but very overcomplicated compared to an aftermarket system that's designed for this kind of thing. If the vehicle the OP is building the magnum for is not a 90's OBD-2 truck, I wouldn't bother with the stock electronics.

I agree with you if the vehicle isn't running an OBD-II system.

but regarding your concerns of "guy on the other end of email writting generic tunes" have you ever used SCT? or are you going by what you've read or heard?

if you have a chassis dyno close by, you can schedule yourself a day of dyno tuning. have them record your HP/TQ levels through the RPM range, read your AFRs via a wideband O2 sensor. if your tune writter is at the other end of email, then you email him that data, he looks at it, adjusts your tune, sends you a new program, and you load it to the computer. takes just as long as if you were tuning a carb motor on a dyno, and it's just as accurate.

If you don't have a Dyno, you can use a wideband O2 datalogger and record RPM, MPH, AFR, TPS, MAP, etc. go make a few WOT pulls just like a dyno would do. email the information to your writter, he again, tweaks your tune and sends you a new program.

It really takes no longer than when you try to tune a carb, and if anything, it's easier! no guessing as to whether it's rich or lean, if your pump shot is too long, too short, too much, too little, etc. It's all in the AFR table from the wideband O2 sensor.

I admit, when I first heard about SCT, I was nervous, confused, didn't understand it, and stayed away from it. but a buddy of mine told me how easy it was, and the programmer I use has the best customer service "in the industry" Now that I've used it, I'm familiar with it, and I know how it works, I know it's limitations, I can say without a doubt, SCT is the way to go until you're building an all out race engine, or you're using a serious power adder.

anyway...we're off topic now from what the OP asked

Posted By: DaytonaTurbo

Re: Milling Magnum heads - 08/16/12 03:35 AM

Yes way off topic but...

How much did your sct tuner plus all those tuning sessions cost? I'm guessing probably a good chunk of the way towards a brand name aftermarket efi controller that could do all that itself. Does the sct datalog is or that an add-on feature? What happens if the guy on the other end is sick? Goes on vacation? Goes out of business? Somehow the idea just does not sit well with me at all. But I do understand that with a factory OBD-2 truck, you're basically limited to something like this if you want your transmission to shift, dash gauges to work, etc.

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/16/12 03:23 PM

$360 for the tuner and unlimited tunes. Bought a used LM-2 datalogger w wideband O2 and OBD-II plug to record PCM data for $200.

What aftermarket EFI system costs under $600 for the computer, harness, sensors, injectors, etc?

Once the tuning is done, it's done, no need to keep going back once a month, unless you keep modifying your motor. Been 2 years, I've done my truck, and helped 3 others do theirs. Same program writer on all of them. Vacation or sick, that can be worked around, just like scheduling dyno time or track sessions to tune a carb or aftermarket EFI.

If you have the hand held tuner already, the PRP software is $350. So you can pick up the handheld used for about $100, buy the PRP for $350, and an LM-2 for $200. Again, less than $700, and now you're writing your own tunes.

Posted By: ChristianCuda

Re: Milling Magnum heads - 08/16/12 03:49 PM

I know this is keeping this off topic but does the SCT tune the 5.7 Hemi's as well and can you eliminate the trans shift for say you wanting to switch to a manual from an auto in the program? Or in my cause removing the trans completely from the program since I am running it in a boat? If so that opens up the doors for me to get almost any stock PCM instead of just a 93 model with the 5.9.

Thanks for the advice feel free to pm me with the details as well. including who your tuner is and where you can find the sct tuners and software.

Thanks Chris

Posted By: 70Cuda383

Re: Milling Magnum heads - 08/16/12 05:20 PM

Quote:

I know this is keeping this off topic but does the SCT tune the 5.7 Hemi's as well and can you eliminate the trans shift for say you wanting to switch to a manual from an auto in the program? Or in my cause removing the trans completely from the program since I am running it in a boat? If so that opens up the doors for me to get almost any stock PCM instead of just a 93 model with the 5.9.

Thanks for the advice feel free to pm me with the details as well. including who your tuner is and where you can find the sct tuners and software.

Thanks Chris

I know with the 5.2/5.9 stuff, you can do quite a bit. you can program the auto transmission stuff out like when you do a manual trans swap on a Dakota R/T, you can also take a Federal emissions program and put that onto a cali-emissions truck if you're trying to delete the Leak Detection Pump...but because even the fed emissions package had the EVAP system, you have to use a resistor to trick the computer into seeing the solenoid when you remove that rats nest of hoses and wires next to the brake booster.

but on the 5.7 stuff, it's a totally different computer and programing--some have the MDS, there's no distributor, and it's all coil pack ignition, etc.

If you want more info on SCT, contact the guy I use, tell him that Tom Filbert sent you. I've built a pretty good relationship with the guy after building my truck and helping other guys with theirs. Sean has even gotten to the point where he'll bounce ideas off of me when one of his other customers are experiencing issues.

Sean aka "hemifever" Hemifever@aol.com and www.hemifevertuning.com

Posted By: ChristianCuda

Re: Milling Magnum heads - 08/17/12 02:48 PM

Thanks that will help a lot.

Posted By: ChristianCuda

Re: Milling Magnum heads - 08/17/12 04:17 PM

Quote:

I know this is keeping this off topic but does the SCT tune the 5.7 Hemi's as well and can you eliminate the trans shift for say you wanting to switch to a manual from an auto in the program? Or in my cause removing the trans completely from the program since I am running it in a boat? If so that opens up the doors for me to get almost any stock PCM instead of just a 93 model with the 5.9.

Thanks for the advice feel free to pm me with the details as well. including who your tuner is and where you can find the sct tuners and software.

Thanks Chris

Just a response looked into the SCT tuner and it does now also tune the 5.7 and 6.1 Hemis, The tuner by itself new from Hemifever is 175 I found one a new on ebay for 149. So buying one used for 100 is okay but will probably go new for me. I sill have to get an intake because that barrel intake is a dog for the rpms I need. Just will make it easier to drop in the FI system later.