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Old 10-17-2000, 06:34 AM   #1
Marco
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Thumbs up Yet, another Cobb Tuning Cam Installed!

Hello there,

I know some of you are thinking about getting the cams installed, so I thought I share my thoughts and impressions about the new Cobb Tuning Performance Cams.

I took the car to Trey's shop last Thursday to get the Cams in, and picked it up Saturday at noon. Allow me to state what the car did before and then what it does now. This is not a technical review of the cams. This is a very much real life experience, which I think most of you are interested in. I personally think this is better than paper.

I have the bad habit of racing my friend in his Prelude. This is a 1999 Honda Prelude 5speed. It has Headers, full exhaust system, AEM Cold Air Intake, Crank pulley, Spark Plug wires (worthless IMO). The car has 200HP stock, so we're guessing between 210 and 220 with all the mods. I'm not sure how Hondas respond to mods, but it is a conservative guess.

Well, every time we race from 0mph, I stay with him until I shift to 3rd gear. Once in 3rd, he starts to walk away from me rather rapidly. If we do a rolling start from 5mph (advantage for him as his car spins the tires with the standing start), he's gone before I hit 3rd gear. Just as a reference, we've raced each other many, many times always with the same results.

Now that I have the cams in (all I have in addition to the cams is a replacement K&N filter, which I had in the car for a while now), this is how it compares to the Prelude:

We did not do a standing start because I did not want to use the AWD launch to my advantage. I wanted to see what the engine does. From a rolling start at 5mph , I started to go and shifting at 6000-6200rpm in every gear. I shifted to 2nd and we're dead even. I shifted to 3rd and he was still beside me. I shifted to 4th and much to my surprise, I turned to the left and he's still beside me. He started to ease away just a bit after 90mph. We couldn't go any faster as the roadblock in front of us was getting closer in a hurry.

I have to say that I'm really surprised about this result. And the reason I'm surprise is because the feel of the car hasn't changed much. You can tell that you have different cams at idle. My car idles perfectly at 650rpm, yet you can feel a subtle shake in the engine. Nothing that would bother anyone, but I can feel there is a different cam profile there. When you're on the gas, it feels almost as the stock cams up until you hit 4000rpm. Before, the engine would start to lose power from 4500 to 6200. It now goes all the way from idle to 6200 with the same will and building power; it feels very linear. This should be no surprise to anyone. If you look at the dyno charts from Trey, you can see that the new cams do a better job all the way to redline. There is no spike like a VTEC engine. The car never takes off. It just works very efficiently with the stock rpm range.

Next mod: I'll be dropping Trey's Intake (when it comes available, that is) and then the new Borla header.

I'm planning on taking the car to drag strip this Friday to see what It does. If I go, I'll post the results as soon as possible.

I hope this information helps you in some way.

Cheers,
Marco
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Old 10-17-2000, 06:36 AM   #2
RidinLow
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Congrats on the install... looking forward to hearing your results from the dragstrip!
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Old 10-17-2000, 07:03 AM   #3
ColinL
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I agree on the idle quality Marco-- it is a tiny bit rougher but not enough for someone who didn't drive it everyday before the change would notice.

I really like the newfound power above 4000 rpm!
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Old 10-17-2000, 07:27 AM   #4
SCOOBYSHAG
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Hey Marco!!

Definitely let us in on your track times!
Good job with the 'Lude! Is the guy that I met at Keller's a long long time ago?

Alex
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Old 10-17-2000, 07:45 AM   #5
Marco
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Talking

Yes, he's the one. So as you can imagine, I've been losing to him for a while. I makes me sick
BTW, I'm sure that by converting the car to RWD, I'll be able to get better times and accelerate even faster. I think for sub 220HP, the AWD system hurts the performance instead of helping. A 220HP RWD Impreza should be really fun car to drive.

Cheers,
Marco

[This message has been edited by Marco (edited October 17, 2000).]
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Old 10-17-2000, 07:58 AM   #6
ColinL
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Since I have a MY99 with no rear LSD, I'll pass on the RWD thing. I do agree that 50% of the power to the front wheels is too much for dry tarmac though.
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Old 10-17-2000, 08:13 AM   #7
Marco
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Colin,

I'm planning on getting a LSD for rear. It will not only help the acceleration, but it will allow me to apply the power sooner during corner exit.
My idea is not only to make it RWD, but I also want to gut the transmission. There is a lot of weight to be saved by removing the front differential, axels, front ring gear, etc. In other words, only necessary components for RWD will be left in the transmission.
I don't think this is a bright idea if you're turbocharging the car and want 300HP out of the engine.
I'm also going to have to tune the suspension as the Impreze in AWD tends to understeer rather heavily. If you don't touch the suspension and change to RWD, the car is going to oversteer a lot. We'll see what happens. I've been wanting to do this since I drove Trey's car.

Cheers,
Marco

[This message has been edited by Marco (edited October 17, 2000).]
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Old 10-17-2000, 08:43 AM   #8
SpeedKills
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I wonder, It should be possible to build an N/A motor that makes as much power as a stage one turbo for right around the same price, right? I mean, cams, exaust, intake, throttle body....
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Old 10-17-2000, 08:58 AM   #9
imprezive
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depends on who is calculating HP acording to ASR their kit make 230 hp at the crank I think it would be tough to make 230 N/A
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Old 10-17-2000, 09:33 AM   #10
Marco
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Big N/A power is a lot more expensinve than force-feeding the engine.

Stage 1 kit turbo can be had for around $2500. Plan for around $1000 for electronic components to aid fuel delivery.

To make 230 HP in N/A trim, you need:

Head Work $2195 (from Trey Cobb)
Cams $499
Aftermafket ECU (timing+fuel+higher RPM) Haltec $1200, or TecII $1950
Throatle body $220
Intake $250
Hearders $500
Muffler $350
Installation (cams, head,) $800

I'm counting on the individual doing most of the installation, such as headers, maffler, aftermarket ECU, intake, throatle body and still you come up with $6014 if you went with the Haltec instead of the TecII.

N/A HP is twice as much as force-fed HP.

Cheers,
Marco
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Old 10-17-2000, 09:38 AM   #11
SpeedKills
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would the electronics really do that much for an n/a car? Trey @ cobb tuning has one (piggyback ecu) for sale....
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Old 10-17-2000, 10:40 AM   #12
ColinL
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My version of that equation looks something like:
  • *cams $399 (now they are $499)
    *DIY cylinder head work -- free (I am 100% positive Trey's heads are MUCH better, but hey-- free is free.)
    *DIY intake (MY99 deleted silencer, removed bumper vent, Subaru fender plug, AMSOil filter) = $40
    *MRT equal length headers, high flow cat = about $350 USD including shipping
    *muffler parts & labor (weld up new piping and muffler to MRT headers) = $300 at most
    *Cobb Tuning throttle body (pending dyno results) = $220
I come up with $1309. Now how much power does it make? Don't know-- ask me when I'm done.

Evaluate performance and decide if a tunable ECU is warranted--most likely it is. I would probably go with the Haltech E6k.

BTW if you're buying ported heads and cams at the same time from Trey, you should be able to convince him to install the cams and set the lash so all you have to do is bolt them up.
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Old 10-17-2000, 11:36 AM   #13
DLC
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Just a quick thought about N/A vs Turbo.

With modifying the cams and intake you're taking these things out of spec and making the engine run more powerful but at higher revs as well.

A Turbo can do most of this but at much lower RPMs. This is why i think a Turbo, with all of it's bits and baubles, is probably the better long-term solution IMO.

Sure, you might be able to make 230HP N/A but you're really thrashing the car at 6500RPM. Turbos do pressurize much beyond the original specs but get a lot more power at lower RPMs than N/A.

I'm sure this has all been debated before.
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Old 10-17-2000, 11:55 AM   #14
ColinL
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I'm sure every single person out there with a 230HP turbo visits redline just as often. There is absolutely more low-end torque, but there's also lag (admittedly, not much with a 9.7:1 CR and low boost) and you'll not convince me that someone is going to short shift at 5k just because they have better midrange.

I like naturally aspirated throttle response. It's there, it's linear.

Anyway, let's not turn this into a turbo vs. N/A debate. Turbo is a (relatively) known quantity, so stand back and see what we can do without. Not much progress is ever made without experimentation.
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Old 10-17-2000, 01:50 PM   #15
ColinL
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1) 5500 rpm is hardly short shifting on a 6250 rev limit, and you said you shifted at redline 2-4

2) All of that is great and well-known by anyone that's been here for any time. It's also a lot more than $1300.

Now will my $1300 get me 230HP? 200? Who knows! Thinking that the $2000 JC Sports turbokit is overwhelmingly superior without even giving N/A a chance is like Mike Shields 2 years ago saying that the only motors that could survive turbocharging came from FHI that way.
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Old 10-17-2000, 08:08 PM   #16
HamFist
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Tastes Great! Less Filling!
This has got to be the oldest argument on here. But, never one to avoid fanning a flame, here's my take on N/A

12:1 pistons.
"secret" cam (It's a big one :})
non-secret headwork
lighter valvetrain,
Better fuel delivery
light flywheel
ACT clutch
Borla header
off-road pipe,
2.5 cat back.
Custom intake plenum (stack fuel injection, or new STI intake manifold.)

Magic total...around 350-450 horse.

Cost? Left testicle.

Go ahead, tell me I'm on smack. I'll be in my garage :}.

Gary
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Old 10-17-2000, 08:27 PM   #17
SpeedKills
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I don't really care how I get the power, I just want it to be reliable and somewhat easy to intall. I like the idea of a "bolt on" turbo or S/C kit (rimmer JCsport 6-8hr.install time), but in reality, I wonder if they actually exsist.
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Old 10-17-2000, 09:38 PM   #18
patr
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don't forget the twin cam motors have a slightly higher redline.

anyone done a cam job on the twin cam motors (and no, I am not wanting to discuss phase I vs. phase II because a lot of people have phase II motors with the twin cam heads)
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Old 10-18-2000, 12:19 AM   #19
imprezive
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I think $1000 dollars is too much for electronics all you need is a FPR and maybe and ITC. Maybe it is right if you are including gauges and housings. But imagine cams +stage I thats where the real powere will come from
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Old 10-18-2000, 12:24 AM   #20
MattC
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I was at Summit Point Raceway last Friday. It was a blast, check out the Atlantic forum for details. All day I was shifting forth at redline, but I would short shift into 5th right around 5500rpms. Why? Because the midrange with the turbo is that good! I was probably dropping no lower than 3500rpms, a point beyond where I hit full boost. Doing this kept my egts much lower(below 1425F), and allowed me to concentrate on the track. I was also still easily reaching 125mph on the front straight, and according to my instructor probably even faster a few times.

With the Rallispec downpipe, the turbo engage is very linear. There is virtually no lag in any gear but 1st. I mean it. I can reach full boost(11psi) before 3000rpms, 7psi at 2500rpms! This is mostly due to a great exhaust system, and a properly sized turbo. Hell, if I had the money I would go after a full T4 ballistic!

I would guess that 5psi would yield about 230hp. The tiny turbo needed to spin that boost level could probably get 5psi by 2k. How often do you find yourself below 2k?

But, 230 N/A HP would be a feat in itself. I just don't think its worth the time or money.

MattC
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Old 10-18-2000, 04:32 AM   #21
WRC666
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Everyone seems to drive at rpms over 4k all the time. On the way to work, I checked my rpms and ,-although I drive at higher rpms to piss the cellphone users off with the popping exhaust-, I hardly went over 4500(for more than 2-3 sec).
I wouldn't like to drive over those rpms for a longer time (haven't been to a track yet) anyways, the noise makes you mad (Borla catback)
So, would those cams be satisfying for everyday driving as well or only for track/backroad time?
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Old 10-18-2000, 02:16 PM   #22
Rich L
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Cool

burninrubber,

The Gig is up! I peeped in that garage of yours and saw that 12000 rpm SOH V-Tec cam lying around!

Haha.. but I pulled that sticker off your bumper and your gonna be slower!
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Old 10-18-2000, 05:47 PM   #23
HamFist
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Well, I will let you in on a few things. My cam grind is rather radical, for what this engine is. I can't get too wild on the lift, because the 12:1 pistons would have to be fly cut, which is very expensive, and makes hot spots for detonation. However, my specs mimic a corvette cam. I see these guys making very very mild cam grinds just to tease you. Since I'll need programmable fuel management anyway, I can get the cams ground just the way I want. JC Sports will happily take the money out of my pocket for this :}.
I've planned my upgrades in two parts: bolt ons, and engine work. Headers and high flow cats and such will go on first, just to "uncork" the engine and see what it does.
Then, with a freshly prepped long-block, bolt it in the place of the stock one. I don't want blow up the numbers matching engine, since it is still a lease on paper.
350 horse is not an impossibility with this engine in N/A form. Reliability is somewhat of a concern, but, that's why I'm going to have two engines :}. I won't say money is not an object in this venture, because it is. I'm looking at about a year for this buildup to be complete. That includes a KYB/AGX suspension as well. My stock clutch already slips, so I may get the flywheel and clutch sooner than expected.
But, as for cams, they have to be specially ground for an all motor car. Emissions is a slight concern, but should be fixed with the programmable fuel injection.
We'll just have to see. I suspect someone with more cash will beat me to it, but they won't be doing it to my car, so I have no excuse to stop :}.

Gary
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Old 10-18-2000, 06:32 PM   #24
MattC
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ColinL,
I was proving that I will shift lower even on a track, because my mid range is so good. On the street I rarely take it up to 5k let alone redline. Even that cheesy 2k JC kit is going to have an enormous midrange. And with the smaller turbo it is going to have zero lag. But, I want the best of both worlds. I am going to pick up the Cobb turbo grind as soon as it is released, and have my heads done in the process.

The $1300 setup you talk about doesn't include any kind of piggy back. Something you will definitely need with a MY99. Your DIY intake is not going to yield the same results as a cone type cold air intake, but it will still leave you with the horrible flat spot at 5500rpms. I would love to see a $1300 N/A setup that yields 230hp, but I just don't think it is possible.

MattC
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Old 10-18-2000, 07:03 PM   #25
ColinL
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Matt-- what flat spot at 5500?
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