speed density and stroker

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Sep 8, 2007 | 05:43 PM

mxzx

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From: yellowknife nt canada

speed density and stroker

I have a 5.8 out of a 90 I'd like to swap into my 86 which has an efi 5.0. Will the speed density ecm be able to handle this if I stroke the 5.8? Will the extra cubes mess everything up? What other mods will the ecm let me to do? I'm looking for big block torque in a small block package. I'd rather not convert to mass air. If this won't work, plan B is a carb 460 swap, then I won't be limited to what I can do. The 5.8 is my first option because I already have the motor.

Sep 9, 2007 | 04:14 AM

dragogt

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From: conroe tx

get a chip burned, or a good tuner, and you should be alright. But without it your ecm will freak

Sep 9, 2007 | 10:17 AM

rswhitmore

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Dragogt is right about the ecm freaking out. It will not be able to properly adjust the air/fuel ratio because the increased air flow of the larger engine will be outside of it's look-up table stored in the ecm. You may be able to correct this with a new chip, but I encourage you do some thorough research and satisfy yourself that the chip will work for your application, the cost, and warranty if it doesn't. You can easily spend a lot of money on the engine, chip, etc and still not have a truck that runs right.

Sep 9, 2007 | 12:21 PM

92f150I6

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From: PA

From what I have read about modifying my 87 speed density mustang, your ecm won't necessarily freak out, but it wont really have the correct calibration. From what I understand, the major problems with speed density arise from cam selection. Since SD fuel injection systems are very dependent on vacuum, you have to choose a cam that works with in the ECM's ranges, you will have drivability problems otherwise.

A SD system can be made to work though. A stock computer can adapt to some mods as it still monitors fuel ratio, and can compensate, just not as well as a mass air system.

Sep 9, 2007 | 12:59 PM

dragogt

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From: conroe tx

yeah, it will probably run. But a cam that's in the ECM's operating range really wont take advantage of the extra cubes, especially with a stroker

Sep 9, 2007 | 03:47 PM

Mr. M

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From: Redmond, WA

Any aftermarket ECU company can accomodate your needs... SCT, Diablo etc. etc.

Don't expect that heavy breathing stroker to work without a custom tune however. If you accurately list your engine specs, most of these companies can burn you a chip to get you in the ballpark of a dialed in tune.

Regards,
Mike