Dragster
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I had a pretty big install project a week or so ago that I had been looking forward to doing: stage 3 Comp cams, a GT350 manifold, oil pump gears, crankshaft sprocket, and ATI balancer. Installation was fairly straightforward, but time consuming. In my opinion, installing cams is actually easier than the oil pump gears, simply because everything is easier to get to. As others have said, the oil pickup tube bolts are a pain to get back in. So if you're doing oil pump gears and you're on the fence about cams, you may as well do them (assuming the additional cost is no problem) since you'll be tearing everything down to get to the oil pump anyway. The hardest part of the install was dealing with two random issues that came up knowing that I had to complete it by a certain time since I had already scheduled the remote tune! In retrospect, I should've scheduled the tune session after I completed the install, but it all worked out.
My goal for the car was to have a meaningful increase in the rev range, and obviously try to increase as much power on the top end while trying to minimize losses down low and in the midrange. My car is not a daily driver, but it still sees primary on the street. Knowing that I wanted to see the difference the manifold and cams made, I made a baseline run on the same dyno where the car would by remote tuned by Lund. My car is a 2015 GT PP manual, and the baseline run setup was a Lund tune, Roush CAI, Reische thermostat, Kooks 1 3/4" green catted headers and Borla S-type catback. The shop had a Mustang dyno, so the numbers are lower than a Dynojet. Baseline was 401 hp. The shop owner said his dyno reads about 8% lower than a Dynojet, give or take, so that would put the car around 430 to the wheels, which seems similar to what other tune and header cars are making.
The car went on the dyno for the tune and results yesterday, and the baseline and results are attached. The car picked up power on the top end as expected, but not nearly as much as I had anticipated. The downside, however, was that it lost power everywhere under about 6,000 RMPs. Not only did it lose power, it lost pretty significant power. Likely far more than the power it gained up top. The peak number isn't listed on the picture, but the shop owner told me it was 422. Needless to say, I'm pretty disappointed. I expected to lose a little power, but not that much, and not for 6,000 RPMs. The gain up top was less than I expected as well.
Jon Jr. did the tune, and he said he doesn't think the before and after pulls are an accurate comparison. He said the data looks good and the MAF is reading 50 lb/min up top. He also mentioned that the manifold alone can pick up 30 hp at 7500 and the cams alone pick up 20-30 rwhp versus stock. I haven't picked up the car or driven it yet (I dropped it off for the tune), so I hope he's right. I like having more RPM to use up top--especially for track days--but the massive loss sucks. Jon Jr. said he thinks these cams work better with a Cobra Jet setup because they lose less down low and carry the power in higher RMP. I didn't really want to have to deal with cutting the hood or lowering the engine though, which is why I went with a GT350 manifold.
At this point I'm just waiting to pick up the car and see how it feels. I was thinking about putting it on a Dynojet in hopes that it might make me feel better.:lol: I'm not really sure what to do otherwise. I almost wonder if the car would be better off with the stock cams... I can't imagine that the cams added that much to the top end, and I know the GT350 manifold doesn't cause the car to lose almost 45 lb-ft of torque throughout the rev range! It's so disappointing to put in all that work (and money) and see those results... Any thoughts on trying to minimize the power loss?
My goal for the car was to have a meaningful increase in the rev range, and obviously try to increase as much power on the top end while trying to minimize losses down low and in the midrange. My car is not a daily driver, but it still sees primary on the street. Knowing that I wanted to see the difference the manifold and cams made, I made a baseline run on the same dyno where the car would by remote tuned by Lund. My car is a 2015 GT PP manual, and the baseline run setup was a Lund tune, Roush CAI, Reische thermostat, Kooks 1 3/4" green catted headers and Borla S-type catback. The shop had a Mustang dyno, so the numbers are lower than a Dynojet. Baseline was 401 hp. The shop owner said his dyno reads about 8% lower than a Dynojet, give or take, so that would put the car around 430 to the wheels, which seems similar to what other tune and header cars are making.
The car went on the dyno for the tune and results yesterday, and the baseline and results are attached. The car picked up power on the top end as expected, but not nearly as much as I had anticipated. The downside, however, was that it lost power everywhere under about 6,000 RMPs. Not only did it lose power, it lost pretty significant power. Likely far more than the power it gained up top. The peak number isn't listed on the picture, but the shop owner told me it was 422. Needless to say, I'm pretty disappointed. I expected to lose a little power, but not that much, and not for 6,000 RPMs. The gain up top was less than I expected as well.
Jon Jr. did the tune, and he said he doesn't think the before and after pulls are an accurate comparison. He said the data looks good and the MAF is reading 50 lb/min up top. He also mentioned that the manifold alone can pick up 30 hp at 7500 and the cams alone pick up 20-30 rwhp versus stock. I haven't picked up the car or driven it yet (I dropped it off for the tune), so I hope he's right. I like having more RPM to use up top--especially for track days--but the massive loss sucks. Jon Jr. said he thinks these cams work better with a Cobra Jet setup because they lose less down low and carry the power in higher RMP. I didn't really want to have to deal with cutting the hood or lowering the engine though, which is why I went with a GT350 manifold.
At this point I'm just waiting to pick up the car and see how it feels. I was thinking about putting it on a Dynojet in hopes that it might make me feel better.:lol: I'm not really sure what to do otherwise. I almost wonder if the car would be better off with the stock cams... I can't imagine that the cams added that much to the top end, and I know the GT350 manifold doesn't cause the car to lose almost 45 lb-ft of torque throughout the rev range! It's so disappointing to put in all that work (and money) and see those results... Any thoughts on trying to minimize the power loss?
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