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Discussion Starter #1
Hey folks haven't been around here for a while but I've recently picked up another 302 car. A 1986 Capri 5spd. Problem is i feel like it's pretty slow for the mods it has. Here's the list as I was told and what I can verify.
explorer short block.
Gt40p heads, verified.
Pro products intake mani/TB
Comp 266 cam, unverified.
Shorty headers/ off road H/ flowmaster 50 series.
Mass air conversion with A9L ecu.
STOCK MAF, air silencer removed. Stock 19lb injectors.

The car feels slow and is slow. Ran [email protected] on a cool day. Granted it's running what I believe are 3.08 gears finished the 1/4 in 3rd at 6k rpm. Race weight about 3300lbs. For reference the last bolt on auto 5.0 LX I had ran [email protected] at the same track.

So far I've moved timing from 10 up to 15 initial. No FPR, so no adjustment. Ran 93oct fuel. Checked for vacuum leaks and loose connections. Car drives around town fine, but when you open it up, nothing. Really seems to struggle over 5k rpms. Could the stock maf be that much of a bottleneck? Haven't pulled the covers to check the valvetrain out yet, doing that later. Is it far off to think this car should trap at least 105? I'm starting to think the cam was not installed properly. I dont think there is any valve float, at higher rpm it still runs smooth just doesnt make any power.
 

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The stock maf is only 55mm iirc. Yes, it's a bottleneck. How much of one is up for debate. I don't think you'll trap 105 mph with that setup at 3,300 lbs, though. I think more like 102 ish is reasonable to expect at that weight. Gearing would help with mph too, especially if it's tongue's hanging out through the traps as much as you say it is. I also think it's likely the cam is holding you back. But you know the drill - "If I'm gonna do the cam, I might as well do the intake - and if I'm gonna do the intake, well I could save 50lbs and pick up 50 hp with heads... and so on."

With these cars you've got to draw the line somewhere; and the costs start to rise exponentially. But I'm pretty sure you know that having had a few foxes.
 

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Discussion Starter #4
I read alot of good reviews about the cam, but I'm not a fan of it. The plan was to buy a fox and put a turbo on it. But if it doesnt work now, shoving air in probably wont get me the desired results. I suppose if it had a 3.73 or 4.10 in it, it would pick up a bit. I dont think those gears would play nice with forced induction without a big tire though. As you said, probably going to put more money than I planned on into it.
 

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Well....i'd start with the unverified cam.
Get the card and a degree wheel, see if it's good for your combo..

Also make sure your valvesprings are suitable.
 

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I did a gt40 intake with gt40p heads while still SD with 19lb injectors. I did a dyno session and it was running lean above 4k rpm. Had to increase the fuel pressure almost 10psi to correct it above 4k but then it was running rich at idle. Eventually I converted to mass air with 24lb injectors and a 75mm meter, ran much better after that.

I'd guess you are running out of fuel with those heads, intake, and cam with the 19lb injectors. Do you know if the fuel pump has been replaced? I bet a bigger meter, 24lb injectors, and a bigger fuel pump (if you have the stock pump) will make a noticeable difference.
 

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With 3.08 gears ? You shouldn't even post until you put at least 3.73s. I would go 4.10 and then consider a mass air (which I would go 80mm on). Put as much timing as it will take. If it starts pinging or starts to slow down back it off .
 

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I would think it would ET a little better. My current car has a stock engine TB to oil pan. 73mm c&l shorty header 2.5 catted H-pipe flows, manual rack and electric fan. T5 4.10 gears. It does have Lakewood lift arms, drag radials, my best pass has been 1.78 60' 13.70 @ 97.7 mph

But with out knowing the DA it's hard to say you are that far off.

Getting a 3.08 car down the track is not easy. My last car had them. It had an explorer motor with HO cam, 65 tb 73 C&L and the exhaust that on the current car. It did produce some 99 mph slips but never got in the triple digits.

Which my cars might be off as well.
 

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By today's standards they are total turds.

Think about it. 225 hp at 4200 and 300 ft-lbs at 3200 is like tractor specs by today's measure. The 3.7 that showed up in 2011 had 305hp at 6500 and 280 lb-ft at 4250. The 2011 V6 ran the 1/4 in about 13.7 at 102. That engine in a Foxbody would destroy the 5.0 in every metric. Hell stock the mighty 5.0 ran 14.6ish at 65ish in the quarter. The new 2011 V6 was still faster by a significant margin. Get the 2011 down to the GT/LX weight and it'd be even faster. My wife's RAV4 is faster.

If you really want to be saddened by the performance of the once king of streets 5.0 think about the output of the 2.3 EB in a light weight package. Then think about it tuned.
 

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Discussion Starter #14
By today's standards they are total turds.

Think about it. 225 hp at 4200 and 300 ft-lbs at 3200 is like tractor specs by today's measure. The 3.7 that showed up in 2011 had 305hp at 6500 and 280 lb-ft at 4250. The 2011 V6 ran the 1/4 in about 13.7 at 102. That engine in a Foxbody would destroy the 5.0 in every metric. Hell stock the mighty 5.0 ran 14.6ish at 65ish in the quarter. The new 2011 V6 was still faster by a significant margin. Get the 2011 down to the GT/LX weight and it'd be even faster. My wife's RAV4 is faster.

If you really want to be saddened by the performance of the once king of streets 5.0 think about the output of the 2.3 EB in a light weight package. Then think about it tuned.
I'm aware of the abysmal performance of the 5.0 by today's standards. I had a tuned ecoboost mustang. My DD is a tuned 3.5 f150. It's a 5200lb V6 truck that gets 25mpg and runs mid 12s. Isnt technology great! Lol.

All I'm getting at is I've owned probably 10 different foxes. Stock to HCI and nitrous. This thing has no punch, anywhere, its performance is on par with the last few stockish cars I've had. Guess I'll have to pull the timing cover and check this cam and dig out my old fox body stuff. And if I'm going to check the cam might as well change it.

Tmoss- thanks for the info, I'll have to get ahold of one of those.

Blackout- I'm not putting gears in it. 3.08 will be fine at 12psi. T5 might not fare so well.
 

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I'm not liking that combo very much. The typhoon should do work at the top where the GT40Ps are wheezing. I don't know much about that cam, but I'd still expect it to run better than a stock 5.0. So, something is wrong. Maybe not firing on all cylinders. Run it and pull plugs. Would probably be best to start with a fresh set. Or put it on a dyno where you can watch the AFR.
 

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The 5.0 needs to be at least a 331 cu in with a good set of aluminum heads (Trick flow / AFR) and decent aluminum intake (edelbrock/ trick flow etc). That is the minimum cost of admission if you want a decent running fox. You need at least 350 to 400 flywheel hp if you want to have a fun driving experience imo.
 

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I have fun when I take my Dad's 100% stock 25K mile '84 GT350 5.0/5speed anniversary convertible out for a drive. It's a turd of the highest order for speed, but it drives really nice and sounds good. 174 hp and 245 lb-ft is nothing to right home about. LOL!!!!

You don't HAVE to have 350-400 hp to have fun. But it sure helps.
 

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The advice in this thread is strange. They seem to be focused on the "turd" part and not much attention to the fact that the car is running like stock with heads, cam, and an intake.
 
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