super coupe motor build for mustang

fast stang16

Registered User
ok guys i think ive figured out what all is needed for the swap! now its time to upgrade! i just bought a comp cam 218/226 .500 .500 112 lsa from gaetz1985. i would like to know which valve springs and retainers do yall suggest? im going to be sure to take as many pics of this build as possible and write a how to thread leaning more towards whole engine swap! the motor is out of a 1992 super coupe btw
 
Valve springs that will fit and valve springs that will be right for that cam are two different things. For a bolt on setup you can only run a single spring but that won't be reliable above 5500rpm. For that cam (which is capable of at least 6000rpm) you want to run a dual spring. To do that you need some machining on the heads in addition to the spring/retainer/locator kit.

I have both available, but highly recommend the dual spring.
 
Double springs are ordered thanks to David! What do you guys recommend on pulley upgrades or any other as tht goes? Will my 30 lb injectors be enough? I picked up the super coupe and it wasn't running soo good rough idle and very little power. Didn't seem to be smoking so hopefully it has to do with supercoupe wiring or just needs a tune up!! I had my uncle go pick it up from the guy I purchased it from and he said it got sideways with him in the road , and I couldn't even get it to spin tires!
 
Valve springs that will fit and valve springs that will be right for that cam are two different things. For a bolt on setup you can only run a single spring but that won't be reliable above 5500rpm. For that cam (which is capable of at least 6000rpm) you want to run a dual spring. To do that you need some machining on the heads in addition to the spring/retainer/locator kit.

I have both available, but highly recommend the dual spring.

Have you had issues with the beehive springs like the ones I am running? Just asking. Thanks
 
I wouldn't even bother putting those 30A# injectors in. Go to 60# injectors and be done with it. Of course, you will need a matching MAF calibrated with a tune, but that is no big deal. The 30# are barely enough to support a stock SC, much less one with Cam and head work
 
Yes ill be using mustang obd2 wiring, still haven't decided whether I'm going to find a place to dump tune it or get a tune from vmp. Will walbro 255 support 60lb injectors?
 
Yes ill be using mustang obd2 wiring, still haven't decided whether I'm going to find a place to dump tune it or get a tune from vmp. Will walbro 255 support 60lb injectors?

A stock fuel pump will even support 60lbs injectors. The pumps purpose is to deliver fuel to the injectors. Yes, a bigger fuel pump,
Such as the 255lph is recommended, and depending on your power levels it's probably necessary, especially in your case
 
A stock fuel pump will even support 60lbs injectors. The pumps purpose is to deliver fuel to the injectors. Yes, a bigger fuel pump,
Such as the 255lph is recommended, and depending on your power levels it's probably necessary, especially in your case

Not so fast. If fuel weighs 6 pounds per gallon do the math.

a 60 pound injector at a 90% duty cycle with flow 54 pounds per hour. Multiply that by 6 and you get 324 pounds per hour. 324 pounds divided by 6 pounds/gallon = 54 gallons of fuel an hour. There are 3.785 liters to a gallon. 54 gallons/hour X 3.785 = 204 liters per hour.

A stock 110 lph pump is undersized for 60 pound injectors. That is assuming you plan on one day running them above 50% duty cycle. Still even at 50% duty which is the equivalent of a 30 pound injector you still need 102 liters per hour. If you think about it the stock fuel pump is barely enough for our stock fuel system.


Absolutely upgrade your fuel pump when moving to a larger injector, unless of course you like playing roulette with your engine. :)

Oh yeah and then compound that with an aging fuel pump that isn't anywhere near as efficient as it was when new and the math even gets worse.
 
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I was going more for the fact that it would deliver fuel to the injectors, not whether or not it will run them at 90% duty cycle :)

My apologies, I should've been more clear
 
Yes but like I said even at 50% a stock pump is barely adequate and that means the stock pump is barely adequate for stock injectors.
 
Yes ill be using mustang obd2 wiring, still haven't decided whether I'm going to find a place to dump tune it or get a tune from vmp. Will walbro 255 support 60lb injectors?

get the walbro 255 high pressure. Stock fuel pressure is 39 with the vac line disconnected. But add 12psi of boost and that regulator is going to be asking for 51psi so you need a fuel pump that flows sufficiently providing 51psi of fuel pressure. The Walbro 255 high pressure pump flows 54gallons per hour at 50psi according to data here: http://www.autoperformanceengineering.com/html/fpspecs.html
 
I will be going with upgraded fuel pump for sure! No I'm on the mission to find a good deal on injectors if anyone knows of any or a good place to get them let me know
 
I will be going with upgraded fuel pump for sure! No I'm on the mission to find a good deal on injectors if anyone knows of any or a good place to get them let me know

Try David Dalke (XR7 Dave on here), he will be able to set you up with a set of 60's.
 
Valve springs that will fit and valve springs that will be right for that cam are two different things. For a bolt on setup you can only run a single spring but that won't be reliable above 5500rpm. For that cam (which is capable of at least 6000rpm) you want to run a dual spring. To do that you need some machining on the heads in addition to the spring/retainer/locator kit.

I have both available, but highly recommend the dual spring.

Dave, care to elaborate? Have read about limitations with the "old style" 26918's but the new and improved 918's offer a .625 lift capability vs the late with .600 lift capability.

http://www.compcams.com/WhatsNew/NewsDetails.aspx?ListHistoryID=1166393320
 
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