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Discussion Starter · #1 ·
Hi everyone, I'm looking for any suggestions and thoughts on my build I finally started got my cobra. Anything you see that doesn't seem right or that you would change let me know. I want to make sure I do this right the first time. The build is as follows: custom built 5.3 bb stroker 11.5:1 compression, fully forged short block, Fox lake ported 03 Cobra heads, Manley valve springs, custom grind bullet cams adv. 279/274 242/[email protected]" 112lsa 0.5" lift, Sullivan intake with Cobra tb adaptor and 47lb Ford racing injectors on stock rails, bbk long tubes with bbk cnc series catted h-pipe, Borla s-type cat back, bbk polished underdrive pulleys, iridium spark plugs, msd blaster coils, act prolite xact flywheel and McLeod super street pro clutch, Canton 6qt oil pan, and DeatschWerks 300m 340lph fuel pump. I'm not sure if it's worth stepping up to the actufab 60mm the or just to use the stock one. Also I'm not sure if it's worth it to get the fully adjustable cam timing set or not. What do you think about these concerns? What do you think of this set up? How much power should I expect at the ground?
 

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Discussion Starter · #2 ·
Anything? Anyone? Haha
 

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I don't know much about building engine, but damn 11.5:1 compression. I thought stock gt were 8:1, what was the stock on the Cobra? Seems like it should be a pretty nice build once it's tuned though.
 

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What fuel? If E85, you could go higher with the compression. You will be losing some dynamically I'm sure. I'm not too knowledgeable but seems like you have covered everything. What are you revving to? What transmission?
 

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Discussion Starter · #5 ·
I'll be running 93 and revving to 7500, with a try I believe is what my transmission is. I know it won't last long behind this engine so when it blows I'm going to t56 Magnum.
 

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Discussion Starter · #6 ·
If I remember correctly the cobras were about 10:1 factory
 

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Sounds like a fun setup. Run some 4.30 gears.
 

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Discussion Starter · #8 ·
4.30s were the plan. What do you all think of the Detroit true-trac?
 

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King Trashmouth
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Looks like a good plan. The upgraded TBs are nice, but are expensive for the return on them. If you really want every last hp and have the change its not a bad idea.

With your RPM goals I'd want to know more about that bottom end. Definitely want it well balanced, upgraded rod bolts at the very least. If you plan to stay NA you can go with the lightest rods you can find. I'd want some sort of windage tray, and at that RPM definitely go for the forged oil pump gears.
 

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Discussion Starter · #10 ·
I'm having modular head shop build the short block and they are adding a gt500 oil pump with billet gears and a 3v windage tray. It's a Manley forged 8 bolt 3.8" stroker crank, Manley forged rods with arp2000 bolts, forged 3.700" cp flat top Pistons with valve notches, and all around hardware for the mains. I also added around head studs and custom mls head gaskets.
 

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Discussion Starter · #11 ·
I got the engine assembled finally and got it in the car. This week I'll be finishing all of the small details up and getting the transmission in. I should be ready to crank it this coming Saturday!
 

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Discussion Starter · #12 ·
Update! Engine is running like a dream. Tune still needs some tweaking, but I'm scheduled for a Dyno tune in the 6th of next month. Anybody have any guesses on final fwhp and or rwhp and tq numbers?
 

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Update! Engine is running like a dream. Tune still needs some tweaking, but I'm scheduled for a Dyno tune in the 6th of next month. Anybody have any guesses on final fwhp and or rwhp and tq numbers?
11.5:1 compression on e85? Damn .500"lift came will certainly make use of the extensive 4v flow rating. I cant imagine what it will do. Good call on the bullet gears and gt500 pump.
 

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Discussion Starter · #14 ·
It's tuned for 93, sadly I don't have either around here. I'm glad I went with the oil pump I did. I have great pressure. I'll post up results when I get it on the Dyno.
 

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Discussion Starter · #15 ·
My car made 385hp at 6500rpm and 344tq at 5600rpm. What I'm trying to figure out is what is limiting my power to 384. It hits that point and holds flat to redline. Any ideas?
 

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It looks like you hit an air flow bottle neck somehow. What is your MAF CAI Filter setup? Did you go with the 60mm TB?
 

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Discussion Starter · #18 ·
Right now I'm on the stock throttle body. It has a lightning maf. I'm averaging 12.9 afr And the timing I think maxed at 23 degrees. The Cai is a 4.5" pvc with 90mm adapter for the mad and the other side of the maf is a 86mm elbow from my old bbk cai. That run was without an air filter on it.
 

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Discussion Starter · #19 ·
I don't think it's my springs only because they are Manley's and I've seen them run much higher rpm on much bigger cams. My Sullivan shouldn't be restricting this motor that low right?
 

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King Trashmouth
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Nah the Sullivan should love that RPM. I would check the spring specs.

The timing seems fairly conservative if I had to guess. The AFR is actually more on the lean side than I would expect, so that's not it.

Do you have a set of stock coils to throw at it and see if that improves it?

I can't imagine the stock throttle body would hold it back that much.
 
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