Efi 351w Swap

90sickfox

Wasn't a pretty sight...and I've got big hands
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Mar 2, 2015
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On my notch the stock cobra springs are so soft I had to put coil spacers ( rubber ones ) to keep the car from bottoming out in the rear. It may be a shock control issue but it's been like that for 12yrs.
 
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nelzfoxes

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Aug 20, 2013
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I doubt the Cobra springs will do you much good. What shocks/struts do you have front and back? Do you feel that the harsh ride is due to the front suspension setup or front and rear? How are your bushings?
Impact up front feels harsh. Out back if I stand on the rear bumper I can get the rear to bounce. Up front it takes a lot more effort to get the suspension to bounce and undulate. It has come to my attention that I installed all springs without isolators. I ordered poly isolators for all 4 corners yesterday. I also ordered 1/2" coil spacers off of amazon yesterday. The coil spacers will go out back. I figure close to an inch of additional height out back. Up front is a question mark. Cobra front springs are 600 lb/in linear. The "B" springs are progressive I believe. I figure the weight of the 351 is using up the soft section of the springs leaving me with the harsh section of the spring for suspension articulation. Cobra springs are shorter than stock fox springs uninstalled. So I expect to maintain a certain amount of lowering although I do not know how much.
 

nelzfoxes

5 Year Member
Aug 20, 2013
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On my notch the stock cobra springs are so soft I had to put coil spacers ( rubber ones ) to keep the car from bottoming out in the rear. It may be a shock control issue but it's been like that for 12yrs.
I agree with you. The rear springs are soft. But it does help to launch the car I would think. The unibody for the Cobra must differ slightly from the fox body because with stock Cobra rear springs the Daddywagon ended up sitting quite low.
 
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nelzfoxes

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Aug 20, 2013
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Impact up front feels harsh. Out back if I stand on the rear bumper I can get the rear to bounce. Up front it takes a lot more effort to get the suspension to bounce and undulate. It has come to my attention that I installed all springs without isolators. I ordered poly isolators for all 4 corners yesterday. I also ordered 1/2" coil spacers off of amazon yesterday. The coil spacers will go out back. I figure close to an inch of additional height out back. Up front is a question mark. Cobra front springs are 600 lb/in linear. The "B" springs are progressive I believe. I figure the weight of the 351 is using up the soft section of the springs leaving me with the harsh section of the spring for suspension articulation. Cobra springs are shorter than stock fox springs uninstalled. So I expect to maintain a certain amount of lowering although I do not know how much.
The “B” springs are the same length as the Cobra springs uninstalled. Because of the higher linear rate I expect the Cobra springs to compress less than the “B” springs.
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nelzfoxes

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It’s done. Springs and spacers are installed. I think it turned out pretty good. The car is raised up... maybe an inch or so. I might try to take it to work tomorrow to see how the ride feels. I say “might” because the clutch is slipping pretty bad.
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nelzfoxes

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I drove it. I even detoured into Philadelphia on the way home to run an errand. It’s definitely soaking up more of the smaller bumps. In order to maintain the softer feel I am gonna install a 4 cylinder mustang swaybar. I think it’s time to go full sleeper... right down to the super quiet exhaust. I will try to incorporate electric exhaust cutouts for those “special” occasions.
 
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nelzfoxes

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I’ve always loved that car.
Thanks! As I've said in the past it's an ongoing project. I would really love to get all the cosmetics taken care of. A six speed manual transmission would be great behind an even more powerful 351 based engine. LED / HID lighting would be fantastic. A class II hitch receiver to replace the bolt on hitch would be a welcome addition as well. 1995 Cobra R rims are also awaiting refinishing and installation. I will turn 50 soon so time and money are the enemies. I am gonna keep-on-keepin'-on!
 
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95BlueStallion

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Thanks! As I've said in the past it's an ongoing project. I would really love to get all the cosmetics taken care of. A six speed manual transmission would be great behind an even more powerful 351 based engine. LED / HID lighting would be fantastic. A class II hitch receiver to replace the bolt on hitch would be a welcome addition as well. 1995 Cobra R rims are also awaiting refinishing and installation. I will turn 50 soon so time and money are the enemies. I am gonna keep-on-keepin'-on!

I really like the Crown Vic wheels on it. Throw a headliner in it and keep tearing it up man!
 

nelzfoxes

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Control arm bushing replacement with polyurethane. I’m trying to get the suspension right. I’d like it to feel like a newer car. It turns out all the bushings were actually fine. But I already bought everything so I am gonna go ahead and finish the job.
 
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nelzfoxes

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The white Criwn Vic wheels, except paint matched to the body’s off white!
White it is! I dropped off the cobra “R” rims to get stripped and powder coated gloss white! White cobra “R”’s should look ok... I hope.
 
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WhiteCobra95

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What about wood-grain Cobra Rs? ;)

P.S. Great build BTW. It was a fun read, and it's always great to check in and see where the project is at. Thanks for posting!
 
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nelzfoxes

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Aug 20, 2013
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What about wood-grain Cobra Rs? ;)

P.S. Great build BTW. It was a fun read, and it's always great to check in and see where the project is at. Thanks for posting!
Thanks! Posting is honestly my pleasure. I don’t do facebook, or instagram, or twitter, or tik tok. I just do the forums thing. I enjoy following other builds and getting ideas from others and sharing what I’ve got going on.