My Comp Cams and GT350 manifold results (spoiler alert: it's not good)

Evil 5.0 said:

I see a couple of mentions so I'll chime in, if you don't mind.

I would wait until Wednesday and see what happens on a dynojet so it is more comparable. If the numbers are still low... you may not like it, but my advice would be to sell your IM and throttlebody, someone will scoop it up real quick.

I would go with the CJ manifold with those cams, it is a proven combination. Another thing that will help with that setup is a PMAS CAI. I don't understand why people are so reluctant to trim the hood. It truly is no big deal and if done right it looks stock.

Not all cars react the same to a given combination. I remember back in the day get an intake, B303 cam and some cars would scream on it and others would lack. Don't give up on the cams, the IM is an easier fix.

I hope it works out for you and if you need anything, let me know.

Good luck.

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I hear ya and I've been thinking about that as well... Swapping intake manifolds and cold air kits is the easier solution, but it's also significantly more expensive than going back to stock cams.

Several people have mentioned getting it to the strip to check the times and trap speed, but I'm not a drag racing guy (I know, I'm in the minority on this forum!). I'm more of a track day and windy road guy, which is why I'm slightly reluctant to cut the hood and ditch the strut tower brace. Realistically though, I really don't know if I would notice the strut tower brace missing.

Regardless, I'm planning on getting the car out today and getting a better impression of how it feels. The weather is much better today, and hopefully the family will let me get away for a while to go for a drive. . I was able to find a Dynojet that was closer that could get me in on Monday, so I'll have results sooner.

You can have an 8000 rpm Mustang that makes peak power at 7500 on stock cams and GT350 manifold, without the down low sacrifice. Area under the curve makes for a fast car at the track (road course)/windy road, and you'll often pull down to 4000 rpm in those scenarios because it's slower to shift. The fact that we have a manifold available with CMVCs that's tuned for peak power near 8k rpm is incredible, as it means you don't have the sacrifices of old with fixed runner lengths and aggressive cams. If you were a drag guy I'd say keep the comp cams and work on getting that better. Since you're not...

Burkey said:

Is PMAS the go-to for the CJ IM? :shrug:

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Yes, it has nice volume and makes the most power

BmacIL said:

You can have an 8000 rpm Mustang that makes peak power at 7500 on stock cams and GT350 manifold, without the down low sacrifice. Area under the curve makes for a fast car at the track (road course)/windy road, and you'll often pull down to 4000 rpm in those scenarios because it's slower to shift. The fact that we have a manifold available with CMVCs that's tuned for peak power near 8k rpm is incredible, as it means you don't have the sacrifices of old with fixed runner lengths and aggressive cams. If you were a drag guy I'd say keep the comp cams and work on getting that better. Since you're not...

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Thanks for the input--I've been thinking about that as well.

My butt dyno didn't notice any loss down low with the GT350 mani. Big gains up top too.


I would get the GT350 TB on there. More flow won't hurt and lund has the tunning squared away with it.

armykyle1 said:

My butt dyno didn't notice any loss down low with the GT350 mani. Big gains up top too.


I would get the GT350 TB on there. More flow won't hurt and lund has the tunning squared away with it.

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I actually asked Jon Jr. about that yesterday, and he told me it wouldn't produce any more power.

Go CJ intake manifold it puts down the most power out of all intake manifolds. I have comp cams stage 3 na with bolts on 47lb injectors and Holley sniper intake manifold it put down 467hp with a Lund tune but The CJ intake manifold, ford racing twin throttle body with comp cams with Lund tune will put around 500hp. The gt350 throttle body is not worth it.

Dragster said:

I actually asked Jon Jr. about that yesterday, and he told me it wouldn't produce any more power.

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I don't see how that makes sense. Maybe a 1-3hp with stock cams, but you should be flowing more with stage 3 cams

armykyle1 said:

I don't see how that makes sense. Maybe a 1-3hp with stock cams, but you should be flowing more with stage 3 cams

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It makes sense if the TB isn't limiting air flow.

UAmach1 said:

It makes sense if the TB isn't limiting air flow.

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On CJs, people gain going from twin 62s to twin 65s. I'm sure there's a gain to be had with OPs setup. If you're trying to maximize HP, you gotta do whatever you can.

If your going to buy more parts, spend a little extra coin and upgrade to a twin 65 and CJ. You know it's a proven combination. You have all the right parts to make over 500 whp NA!

I will say I would expect your combination you have now to put down 480 or so, so something is up somewhere. Get it on a dyno jet so we are for sure we are comparing apples to apples. I have worked w Jon Jr. And Lund and met him in person. He knows what he is talking about, so you are in good hands.

So I got a chance to finally drive the car to get a good impression of the changes over the weekend. Here's the positive: I like being able to rev to 8,000 RPMs. Here's the negative: the car definitely feels down on power. Even at the top end of the power band, the car never seems to pull like it should. Overall, the car just feels slower...

I had an appointment to get the car dynoed on a Dynojet today, so I've attached the graphs. The results speak for themselves: a grand total of 439 hp and 359 ft-lbs. The results are SAE (smoothing was 5), even though it's not listed on the printout for whatever reason. Not exactly what I had in mind when I decided to do cams and an intake... I'm honestly speechless. For comparison, the shop owner pulled up two S550s that were intake, exhaust (one had headers), and tune, which is similar to what my car had before the cams and manifold. The results for my car are in red, and the comparison cars are in blue. I know we're not supposed to be comparing different cars on different days, but the dyno is the same and the results are all SAE corrected, so you can still draw some conclusions. And the end of the day, my car makes (barely) 15-25 more hp than the other two cars at peak, but is down 22-26 ft-lbs at peak as well. More telling is the difference in torque curves between the two non-cam/manifold cars as well: at just over 4,000 RPMs, my car is down 53-56 ft-lbs. Just like the original before and after dyno I did on the Mustang dyno, my car is down on hp and torque compared to the other two cars for nearly 6,000 RPMs, and then it starts to pull slightly ahead. Slightly. We're talking 15-25 hp. Yes, it does pull for another 1,000 RPM, but IMO it simply doesn't offset the large losses in the low to midrange.

After installing cams did you do a KAM and crank position sensor relearn?

Kahboom said:

After installing cams did you do a KAM and crank position sensor relearn?

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Long story short, yes. The timing was off initially as verified by Jon Jr, so we had to tear it down again to re-time it. Did that and the crank relearn, and he said it was good. According to Jon Jr, the data looked good, but he didn't think the numbers looked correct. Unfortunately, they apparently are.

Did you have Dyno numbers before you tore a back down and then Dyno it again or are these just the final numbers. Something seems off man