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Old 10-02-2005 | 06:49 PM
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Default Need help with cam only car issues....

I have a 99 TA M6 with 31k miles. It has most bolt ons and a MS3 Magic stick cam. Tuned it made 403hp and 384lbs tq with 28 degrees of timing. With the timing at 24 degrees(for nitrous) it makes 399rwhp. After a 4.10 gear install recently the HP dropped to 381 and tq was 368. I have had the car at the strip twice and it just will not run the numbers.. I am running it on nittos drs and it is around 3700-3750lbs depending on fuel level. I 60' between 1.98-2.10 and the car is only going 12.70s-12.90s@110-113
I have narrowed the problem down to the 330' area. Its only going 5.50-5.60 in the 330' and with a 2.0 60' it should be going around 5.0-5.10. My 1/8mph is only 87-88 mph which SHOULD be around 90-91 for the rwhp. It was running exactly these same numbers both times at the track. First trip out was with the 3.42s, I thought for sure it was a bog problem so I stuck the 4.10s in it and although it FEELS much quicker on the street, on the track its not showing it. I leave around 2-3k rpms and I was knee jerking the clutch out and dumping it. It hooks fine. I did try to dump it at 3500 and it spun all through 1st. The car seems to run fine on the back half gaining 24-26mph but its just horrible in the 1/8. It seems like there is just NO torque to pull the car out of the gate once the clutch is out and the rpms are around 2500-3k, its a slow climb to 4500 when the power comes on. I am shifting around 6400 indicated which is around 6700 in reality. WTF do I need to due to get this thing to run what it should be running? On the dyno charts it shows to be making 300ft lbs of tq at 3k rpms so... its not THAT weak but the car is a total turd. Do I need the 12bolt rear first so I can dump it at 6k JUST to get it to 330' decent or should I look into a cam swap? I love the Magic stick sound but its just too weak for this heavy car down low. I am thinking of finding another dyno to try, maybe my local dyno was happy? This thing should be running 12.20s@115 with 2.0 60's easing it out of the gate.

Any ideas of what I should do? I have spent a ton of money on this thing and it runs like a stock car. I wish I would have bought an auto now.... this thing is 80% street and 20% track so I won't be doing weight reduction and drag suspension etc.. The car does have a 2" drop hotckis springs, Random adj torque arm, Mac LCs.

Thanks in advance for any help!!
Old 10-03-2005 | 01:16 PM
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Damn no one?
Old 10-04-2005 | 01:53 PM
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TOP, I am sure someone else that actually races has seen this issue before??? I am thinking the cam is just too big and its killing the low to mid range torque. Not sure...
Old 10-04-2005 | 03:43 PM
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Originally Posted by Vortec5300
TOP, I am sure someone else that actually races has seen this issue before??? I am thinking the cam is just too big and its killing the low to mid range torque. Not sure...
I think you are right. I just don't want to be the guy that says it. I'm sure others feel the same way so they haven't posted a reply.

I've personally seen guys overcam their setups and although they may trap higher, they usually don't ET any better or their ET gets worst. As you mention vehicle weight & gearing (tranny&rearend) all factor heavily into finding an optimum cam. It seems dynos are blind to those important factors.

I've watched the popular cam selection trend over the past 3 years grow incrementally bigger and bigger as vendors battle it out using dyno numbers to support their claims. I've also seen less and less posts from guys hitting respectable ETs for their listed mods that were once common 3-4 years ago. Is there a connection?

Of course there are guys who are doing very well with the larger cams because they know how to set it up right. I'm talking about the directions given to the average Joe that comes on here looking for performance. You know, the guy who starts a thread saying he wants a cam that makes ~400hp, doesn't want to lose any lowend, and wants a strong lope. There are guys that spew out recommendations based on what they have read and not from personal experience. Then the poor guy gets all caught up in it and can't help but look at dyno graphs. Then he makes a crapshoot decision. Some guys walk away satisfied while others not.

I have this bit of advice to offer you. Watch out for guys giving advice. LOL!

I'm pretty sure that I am not anywhere near 400 hp, but my 1/8 & 1/4 traps are comparable to yours. ETs are all about the first half of the track. Strong mid-range cams help the first half.

Good luck. (Flame suit on)
Old 10-04-2005 | 08:51 PM
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It's harder to get a heavier car moving, especially launching at a low rpm.
Old 10-04-2005 | 09:07 PM
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It may be in your launch.I have a B-1 which is usually discounted as old school but pulls hard all thru the rpm range and shifting at 6200 I still run high 11's at almost 118 off the street on DR's.I can't dump the clutch at 5k and not have a spin so I do a controlled slip of the clutch to keep the RPM up and net mostly high 1.7/low 1.8 60's.I know what you mean but the car not climbing on top of the cam but building slowly and then freight training,it happens to me when I either slip it too quickly or spin,I"ll dump a few tenths and lose a few MPH.Practice letting out the clutch slow and keeping the RPM's up,when you get it you'll feel it pull hard all the way up.You"ll also have to have a good clutch setup to do this.Good luck.
Old 10-04-2005 | 10:37 PM
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Originally Posted by 01-Z
It's harder to get a heavier car moving, especially launching at a low rpm.
EXACTLY. You can't complain about your car not running the numbers it should if you refuse to lighten it up. your times seem about right for a 380 rwhp, 3750 lb car with no suspension mods on drag radials.
Old 10-04-2005 | 10:50 PM
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Do you have a 12 bolt? Do you have a good clutch?
WHy are you launching so low in the rpm range?
You should be sidestepping the clutch at 6K.
If on the spray, maybe 4500.
There is no reason why you can't 60 foot 1.7s on your set up.
You have to get agressive out of the hole.
If you are scared of breaking, then you are on the wrong path.
Hold that thing at 6K and as soon as that last yellow is on, BAM.
Off the clutch, mash the gas, and feel that you got rearended by a bus.
(Make sure you do a good burn out)
Old 10-04-2005 | 10:55 PM
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Wait, I just saw you don't have a 12 bolt and a good clutch yet.
That is the problem.
You will never be able to come out of the hole hard without doing these changes.
Let me put it to you this way, 430 HP and I never got into the 7s until I got a 12 bolt and a good clutch.
After a couple of passes, bam Mid 7s all day long.
It makes launching the car so much easier. No need to think about bogging or anything.
Just use a line lock for a burn out, hold rpms at 6K, release.
Old 10-04-2005 | 11:11 PM
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Originally Posted by glennster
It may be in your launch.I have a B-1 which is usually discounted as old school but pulls hard all thru the rpm range and shifting at 6200 I still run high 11's at almost 118 off the street on DR's.I can't dump the clutch at 5k and not have a spin so I do a controlled slip of the clutch to keep the RPM up and net mostly high 1.7/low 1.8 60's.I know what you mean but the car not climbing on top of the cam but building slowly and then freight training,it happens to me when I either slip it too quickly or spin,I"ll dump a few tenths and lose a few MPH.Practice letting out the clutch slow and keeping the RPM's up,when you get it you'll feel it pull hard all the way up.You"ll also have to have a good clutch setup to do this.Good luck.
Here's a great example of a strong mid range cam that was very popular a few years ago that traps 118! This type of cam is much more forgiving of a mediocre launch than larger cams.
Old 10-05-2005 | 08:33 AM
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I think that your race weight is the biggest factor.
With that cam you will need a lighter car and/or as much gear as you can get.
Try adding more gear and tire to reduce your short time.
4.30 gears and 25.5 tire would let you MPH 120 @ 6800 rpm, but I would recommend going with a 12 bolt/4.56 gear and a 27” tire like QTP that would allow you to spin a little before hooking to get some momentum with less bog.
You are correct that you need to get the 60’s down but more important is 330’s
M6 cars need to launch hard to get good 330!
Good luck, you have the right idea
Old 10-05-2005 | 12:14 PM
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THANKS FELLAS, Finally some good advice. I am thinking with the weak low end power, its gonna take dumping it at 5+k to keep the rpms from falling below 4500rpms. I do have 4.10s but in a stock 10bolt so I was not dumping it real hard. I did dump it from 3500 once and it lit up the nittos. I was hoping with the 4.10s I could slide it out of the hole some and the increased gearing would help the motor do the work but it made NO difference over the 3.42s. I have several buddies with full weight TAs going 11.80s@118-119 with cams and 6 spds but their cams are smaller and they have ported, stock CC heads. I would rather stick a 12Bolt in it with 4.10s and 26" ET streets and dump the **** outta it as opposed to swapping cams. I am spraying 150hp so 4.33s wont work for me on nos.

THis cam is definetly way too big but thats what TSP recommended to me for my setup so I went with it. I am thinking a 224/228 would have been a much better choice.

BTW My car went 12.90s@108.5 with only a lid, borla and 26" et streets so all of my bolt ons and cam seem to be adding nothing in the real world although showing 80+ hp gain on the dyno. I really don't want to change cams, I think I will try the 12bolt and a hard launch first.

I thought my 1.98 60' was not TOO bad but it should have helped the 5.58 330'. Maybe with a 1.7-1.8 60', the rpms will stay in the sweet spot(4500+) and 330' car. Even after the 4.10 install in a 95 degree shop the car made 381hp/36x tq so, the power can't be THAT far off. If it was an auto with a 4k stall I don't think I would have this problem.

Thanks again guys...any other info is appreciated.
WHo thinks I should swap cams to a smaller one?
Old 10-07-2005 | 08:46 AM
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I don't know about you, but once we start side stepping that clutch (mine's the stock z06 clutch) at 5-6k out of the hole, we're not only rolling the dice with the rearend, but also with the clutch.

Basically, I think our problem is that we need to sink another $3,000 into our cars, LOL.....or go A4!

Keep in mind Vortec, my cam isn't as big as yours either, 227/224 112 , lower lift...
Old 10-07-2005 | 11:54 AM
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Originally Posted by Vortec5300
THANKS FELLAS, Finally some good advice. I am thinking with the weak low end power, its gonna take dumping it at 5+k to keep the rpms from falling below 4500rpms. I do have 4.10s but in a stock 10bolt so I was not dumping it real hard. I did dump it from 3500 once and it lit up the nittos. I was hoping with the 4.10s I could slide it out of the hole some and the increased gearing would help the motor do the work but it made NO difference over the 3.42s. I have several buddies with full weight TAs going 11.80s@118-119 with cams and 6 spds but their cams are smaller and they have ported, stock CC heads. I would rather stick a 12Bolt in it with 4.10s and 26" ET streets and dump the **** outta it as opposed to swapping cams. I am spraying 150hp so 4.33s wont work for me on nos.

THis cam is definetly way too big but thats what TSP recommended to me for my setup so I went with it. I am thinking a 224/228 would have been a much better choice.

BTW My car went 12.90s@108.5 with only a lid, borla and 26" et streets so all of my bolt ons and cam seem to be adding nothing in the real world although showing 80+ hp gain on the dyno. I really don't want to change cams, I think I will try the 12bolt and a hard launch first.

I thought my 1.98 60' was not TOO bad but it should have helped the 5.58 330'. Maybe with a 1.7-1.8 60', the rpms will stay in the sweet spot(4500+) and 330' car. Even after the 4.10 install in a 95 degree shop the car made 381hp/36x tq so, the power can't be THAT far off. If it was an auto with a 4k stall I don't think I would have this problem.

Thanks again guys...any other info is appreciated.
WHo thinks I should swap cams to a smaller one?
i have the same problem with my ms3 the best i could get was a 8.55 at 83 mph my stock times was trapping 85mph. what get me is my 60ft time suck my best with the ms3 was a 2.0683 on street tires. but when my car was stock i was running 1.85 sixty foot time. my best stock time was 8.6 and im making way more power. my car is a 01 ss six speed with a ms3 lid s3 throttle body po pulley yet and free mods dyno number 391hp and 360 tq
Old 10-07-2005 | 12:02 PM
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for a street car.. you overcammed it. that cam, or anything in the 235+ duration range (my opinion ) for a street car is kinda lame, it is so dead in teh bottom end that teh car will alot of the time feel worse then stock. Big cams have a place, in race cars. If you are unwilling to lighten the car, I'd advise getting something in the 224 to 230 range on duration ( split it for your nitrous, a 224.228 would be perfect probably ) and as much lift as you wanna run, again, nothing extreme needed her, high 580's would be fine. You'll find something like that would be much more siuited for your car, and the use you give it.

When you are ready to have a race car.. stick that cam back in, you'll be all set.
Old 10-07-2005 | 12:05 PM
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the tq #'s guys are what are killing all of you.. a peak of 360 tq is terrible. My car made 368 when it was bolton only with headers.

these big cams, under 4500 are really dead in most cases. Keep that in mind, and set the car up to run over 4500 and you are all set. Stick that cam in somethin that is gonna be driven at anything less tehn 3000, and it's gonna suck. Sorry for being harsh, but it's true.
Old 10-07-2005 | 02:54 PM
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But doesn't his cam still make the same or more hp and torque DOWN LOW than his stock cam did?
Old 10-07-2005 | 04:58 PM
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I'm guessing no. Most of the cars I see that go with a bigger cam lose power under 3K.. and the lower in the RPM you go, the more they lose, I've seen as much as 25 hp and 35 tq at 2000 rpm loss with a big cam vs. a smaller cam. If you have a street car, and are trying to run it at the track, and are launching it at a low rpm.. it's gonna run like ****. The only way to run a big cammed car period is to rev the **** out of it.. and if you are on stock driveline, good luck.


I really wish the people that are making these big sluggers would be more honest with people about the application.

Some shops are.. but I'm gonna say that the majority are just trying to push their big name cam on people to make a buck.. they aren't really intrested about the customer's car, or what they are doing with it in a realistic manner.
Old 10-07-2005 | 05:56 PM
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Originally Posted by JL ws-6
I really wish the people that are making these big sluggers would be more honest with people about the application.

Some shops are.. but I'm gonna say that the majority are just trying to push their big name cam on people to make a buck.. they aren't really intrested about the customer's car, or what they are doing with it in a realistic manner.
Actually they are. LG and Thunder have both told a few friends of mine that the G5x4 and T Rex aren't very streetable.
To me they are but of course to me streetable is a completely different thing than it is to most people.
Old 10-08-2005 | 05:40 PM
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You guys are hitting the nail on the head. Eventhough the dyno shows 300ft bls at only 3k rpms, its under that range where it sux. If I dump it at 3500 and it hooks, it falls to around 2k and its a long slow crawl up to 4500 when it finally takes off. The only reason I went with the MS3 is because this is what Texas Speed recommended. I told them it was a full weight car with stock gears and M6. He told me it will "feel" a little weaker down low then stock but its really just because the top end pulls so much harder. Basically, if you don't have a 4k stall converter or a 3000# car, this cam is junk. I am STRONGLY thinking about switching to a TR224 or something of the like, not to mention it won't kill valve springs like this thing will. I can not see having to spend $3k on a rear end, JUST so I can dump it at 5k, JUST to make it run low 12s. This thing should be able to drive outta the gate and run low 12s. Not sure what I am going to do. Don't really have the money to pull the cam, install a new one and re-tune everything right now. Guess I gotta live with it for a while. Don't get caught up in dyno numbers people. BUT the 4.10s feel like they made a big difference on the street, the track doesn't show it. Funny thing is, I ran a dude with an SS a few weeks ago, cam only, all bolt ons just like mine but he had a small cam and we were neck and neck from a 20-120mph roll. My car seems ok from a 20 roll, anything under that and its a turd. I can put the block off plate back in the borla and it does seem to help part throttle torque quite a bit but... either way I spent $4k on mods and my car runs like a stock one.



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