Place your bets:
Thread Starter
5th Gear Member
Joined: Dec 2005
Posts: 2,060
From: Okla.
RE: Place your bets:
Lol, I am not near as upset about it now as I was when I typed that all up.. man.. nothing hurts your confidence worse then pulling a lousy time on a video [&:] .. EDIT: also.. the thing that made me the most upset about it.. and my friends kept railing me about.. is I was almost a full second quicker in my v6 then I was on that final run I made.. lol, now that will get under your skin in a hurry.
I have plenty of mods planed for it.. it wont stay stock for long.. I think I am going to take care of the U/L CA's, DR's, and Subframe connectors first... was planning on doing engine work.. but I wanna hook with the power I have now. I might get those done this week or next week and get another run in.
I have plenty of mods planed for it.. it wont stay stock for long.. I think I am going to take care of the U/L CA's, DR's, and Subframe connectors first... was planning on doing engine work.. but I wanna hook with the power I have now. I might get those done this week or next week and get another run in.
6th Gear Member
Joined: Nov 2004
Posts: 7,797
From: Tennessee
RE: Place your bets:
ORIGINAL: Bullitthead
I think you may be expecting a little too much out of your car, Hav. Assuming that your car is a stock '97 Cobra with 4.10 gears (a mixed blessing on street tires), your first E.T. was actually pretty good. You might be able to run something in the 13.90's but, just as Sidewayz6.0 said, that's about all you're going to get until you go to DR's.
While the 96-98 Cobras supposedly produced 300hp, even MM&FF couldn't crack the 13's with a stock one when they tested it in '96. Regardless, your engine has a lot of potential thanks to those 4v heads. Don't get discouraged! Tracks tend to lose traction when lots of drivers with street tires make runs, and your experience of having a good early run (when traction was still good) followed by progressively worse runs as traction breaks down mirrored my own "Test&Tune Session" this weekend...
I think you may be expecting a little too much out of your car, Hav. Assuming that your car is a stock '97 Cobra with 4.10 gears (a mixed blessing on street tires), your first E.T. was actually pretty good. You might be able to run something in the 13.90's but, just as Sidewayz6.0 said, that's about all you're going to get until you go to DR's.
While the 96-98 Cobras supposedly produced 300hp, even MM&FF couldn't crack the 13's with a stock one when they tested it in '96. Regardless, your engine has a lot of potential thanks to those 4v heads. Don't get discouraged! Tracks tend to lose traction when lots of drivers with street tires make runs, and your experience of having a good early run (when traction was still good) followed by progressively worse runs as traction breaks down mirrored my own "Test&Tune Session" this weekend...
PS hav I think thats what you are missing. A good track. lol.
1st Gear Member
Joined: Feb 2006
Posts: 72
RE: Place your bets:
I've always wondered why the 96-98 Cobras weren't faster myself. In fact, they seem to have nearly identical performance to a '99-'04 GT, despite 40 extra bhp. Why? I did a tiny bit of research and discovered that the '96-'98 Cobras were about 200lbs heavier than a 99-04 GT. That's two tenths, or twenty horsepower, right there. I imagine that this is primarily due to the huge heads the 4v engines have. They really fill out an engine bay!
Anyway, that still leaves 20 bhp on the table unaccounted for. Where did it go? I have a few ideas:
My pet theory has always been that Ford simply overrated the horsepower. We all know they got busted with the '99 Cobras, and they took like men and fixed the problem, but it seems very possible that the '96-'98 Cobras were a bit overrated as well. However, Hav and others claim to have dynoed 260+rwhp, so maybe not.
My only other guess is that the relatively low torque (300 ft-lbs.) of these engines made them slightly slower off the line than a '99-04 GT, but would explain why they usually trap about 1mph higher. I really don't know.
What's interesting is that the new 05-06 GT's weigh about 100lbs more than a 96-98 Cobra and have the same horsepower, but have produced E.T.'s in the 13.5-13.6 range at 104+mph. Hmmmmmm....
Anyway, that still leaves 20 bhp on the table unaccounted for. Where did it go? I have a few ideas:
My pet theory has always been that Ford simply overrated the horsepower. We all know they got busted with the '99 Cobras, and they took like men and fixed the problem, but it seems very possible that the '96-'98 Cobras were a bit overrated as well. However, Hav and others claim to have dynoed 260+rwhp, so maybe not.
My only other guess is that the relatively low torque (300 ft-lbs.) of these engines made them slightly slower off the line than a '99-04 GT, but would explain why they usually trap about 1mph higher. I really don't know.
What's interesting is that the new 05-06 GT's weigh about 100lbs more than a 96-98 Cobra and have the same horsepower, but have produced E.T.'s in the 13.5-13.6 range at 104+mph. Hmmmmmm....
Thread Starter
5th Gear Member
Joined: Dec 2005
Posts: 2,060
From: Okla.
RE: Place your bets:
I'll post my dyno sheet up here. It was before I pulled out my terrible plugs that were in desperate need to be repalced and changed my fuel filter (I hadnt even had the car a month when I got it dynoed). The car is nowhere near as choppy feeling in the high end as it was before. I was having some issues that are now fixed. It will give you guys an idea of the torque curve of one of these cars. Its kind of odd.. its pretty flat untill it spikes when my secondary's open.. then drops again and finally takes off. I think the trick for me when I make it back to the track would be to get to the point where I can launch over 3250rpm's.. if I can take off with the secondary's open that would probably help my times a lot.. but I cant. lol.
EDIT: fixed link.
EDIT: fixed link.
Thread Starter
5th Gear Member
Joined: Dec 2005
Posts: 2,060
From: Okla.
RE: Place your bets:
ORIGINAL: Bullitthead
Err, Hav, you do realize that fuel-injected cars don't have secondaries? That term refers to the secondaries opening on a 4bbl carburetor...
Err, Hav, you do realize that fuel-injected cars don't have secondaries? That term refers to the secondaries opening on a 4bbl carburetor...
DOHC = a primary and secondary set of valves equaling 4 valves per cylander (2 intake and 2 exhaust). When I refer to my secondary's opening I am talking about the second intake valve.. My terminology might be slightly off.. but hey.. thats why its my terminology [8D]
Placed above each secondary intake valve is a 34mm butterfly port throttle. Below 3,250 rpm, the port throttles are closed, thus blocking airflow to the secondary valves. With only one valve feeding each combustion chamber at low revs, airflow velocities are higher, and the mixture motion is faster, resulting in better cylinder filling and quicker, more complete burning of the fuel-air mixture. The curved lip around the inlet of the primary intake valve initiates and directs the mixture of the intake charge in the combustion chamber. This results in lower exhaust emissions and increased low-end torque.
From 3,250 to 7000 rpm, the engine computer commands two things to happen: cables actuated by an electronic motor flip the port throttles, allowing a nearly unrestricted flow of air through all 16 intake vales at mid and high rpm; and the injectors provide more fuel to the cylinders. The port throttle design helps provide ample torque down low, while taking full advantages of the engine's high-end capabilities from the four-valve head design.
From 3,250 to 7000 rpm, the engine computer commands two things to happen: cables actuated by an electronic motor flip the port throttles, allowing a nearly unrestricted flow of air through all 16 intake vales at mid and high rpm; and the injectors provide more fuel to the cylinders. The port throttle design helps provide ample torque down low, while taking full advantages of the engine's high-end capabilities from the four-valve head design.
EDIT: and a pic for ya
No offence meant.. just making sure you know that I do have some idea what I am talking about
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