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KaminaSan
03-04-2011, 09:53 PM
Hey guys, when looking at fully building my SR, I've come across a slight issue.

My head has BC Springs and Retainers, Rocker Arm Stoppers, and I'm looking to go with aftermarket cams and Sprockets.

The issue is, I'm not going to be breaking the engine in with an upgraded turbo or anything(can't afford the PowerFC I want atm)

I'm looking for a good street driven powerband, hopefully in the lower rpm range(3500-6000)
Is it safe to run a 256/264 HKS cam setup w/ Adjustable timing sprockets, without any ECU tuning for break in period?

The most I will be looking to get with this setup is 350-375 horses. I'm mostly interested in torque.

jr_ss
03-04-2011, 11:57 PM
I'm going to say search....

But yes, tuning for any cam change is a must. Granted, you should be taking it easy on the engine break-in period, but that doesn't mean you won't dip into it every once in a while. I wouldn't trust it and I'd say get the tune or leave the cams out for break in.

KaminaSan
03-05-2011, 12:08 AM
I'm going to say search....

But yes, tuning for any cam change is a must. Granted, you should be taking it easy on the engine break-in period, but that doesn't mean you won't dip into it every once in a while. I wouldn't trust it and I'd say get the tune or leave the cams out for break in.

Anyone else care to chime in on this? What would be the risks, assuming timing is correctly set?

4x4le
03-05-2011, 08:33 AM
As long as your on stock injectors, stock maf, and stock compression I wouldnt see the big deal. Just dont be getting on it.

Now the problem I see is you asked if you can break the engine in on different cams without a tune. And I say yes. But a break in probably takes much less time than most people think. And you say that you cant afford the ecu you want at the moment. So Im thinking you might be asking us for permission to drive around for an extended amount of time without a tune and I wouldnt do that.

I usually consider my motors broken in within a couple hours (rings seated). It will take longer than that to save up for an ecu.

KaminaSan
03-05-2011, 01:33 PM
As long as your on stock injectors, stock maf, and stock compression I wouldnt see the big deal. Just dont be getting on it.

Now the problem I see is you asked if you can break the engine in on different cams without a tune. And I say yes. But a break in probably takes much less time than most people think. And you say that you cant afford the ecu you want at the moment. So Im thinking you might be asking us for permission to drive around for an extended amount of time without a tune and I wouldnt do that.

I usually consider my motors broken in within a couple hours (rings seated). It will take longer than that to save up for an ecu.

This is what I was wondering. How negatively would cams affect my engine without a tune? What dangers would I run with a very mild setup? Let's say even 256/256?

R33E8
03-05-2011, 02:06 PM
I think if anything you would go leaner due to more air entering the engine.. but the MAF might compensate for the additional airflow..

4x4le
03-05-2011, 04:18 PM
Where the real problem will lie is your shifting your peak tq area and you might need less timing there.

The real truth is I wouldnt know for sure. To me a tune is more important than any part and i would never upgrade any part unless i was prepared to do a tune.

An all motor ka scca car that came through to get tuned for example.
High compression, ported head, large valves, big cams, race fuel, ect. On a dyno dynamics it made like 93whp and then i tuned it and it made 175whp.
Performance parts hurt your engine unless your tuned for them

Sent from my rooted Incredible using tapatalk

jacobs13
03-06-2011, 06:37 PM
I have 254 564 cams in my motor and I just put stock injectors, maf etc. It runs rich as shit, it will burn your eyes if your head is in the bay when its on. I do have a fully built motor though so that might take a big part in my problem

KaminaSan
03-06-2011, 06:57 PM
That's basically all I needed to hear. My engine is also fully built, and the last thing I need is to run super rich and get ring wash.

jacobs13
03-06-2011, 07:53 PM
Yeah dont do it or try not to, there is wayyyyy too much money in that motor to harm it

4x4le
03-06-2011, 08:40 PM
I just noticed something in the first post. If your mostly interested in tq why did you go with bigger cams?
Most of the time I see dyno sheets of people with cams I see higher hp at higher rpms, but later spool up and less low end tq.

I just found damage on my intake cam on lobe 1 and Im trying to find a clean set of stock cams even though everyone seems to try to be pushing me to get cams they will pretty much have the exact opposite result than what I want.

I would love to get some stock n/a cams because they are like right between stock det cams and a small aftermarket cam.

LongGrain
03-06-2011, 08:55 PM
I ran my SR with HKS 264 step 2 in/ex, and s14 T28 at 14psi and other mods w/ stock injectors, maf and ECU. No tuning at all and that thing fucking RIPPED, never had a problem and the motor is still running in someone elses car today.

jacobs13
03-06-2011, 10:09 PM
^^^ Really? That gives me hope because I have almost the same setup, but one of my injectors is dead and my wiring had a bunch of problems but I think i fixed them all, but even when its running ok people behind me say it smells strong

KaminaSan
03-07-2011, 12:48 AM
I ran my SR with HKS 264 step 2 in/ex, and s14 T28 at 14psi and other mods w/ stock injectors, maf and ECU. No tuning at all and that thing fucking RIPPED, never had a problem and the motor is still running in someone elses car today.

Possibly ripped because of the engine leaning out? How were your AFRs?

codyace
03-07-2011, 07:45 AM
I just found damage on my intake cam on lobe 1 and Im trying to find a clean set of stock cams even though everyone seems to try to be pushing me to get cams they will pretty much have the exact opposite result than what I want.

If any car I'd love to see a direct comparison on, it would be your car. Obviously it may be a unrelated type graph as you have the ability to tune it over some of the MAF guys, but I'd love to see your car with some cams in her.

To me, there is a fine line of response vs. average power...me being a 'spool it as fast as you can guy' can even agree that at times it's not worth the extra low end (especially as my car is a track based car anymore) if you can make much more midrange torque and top end power, as that's where the car is most of the day. With having the dyno around, anymore I'm not even looking at peak or early times at this rate, only average power and then over time frame...which is something MANY do not even look at...(and Im' sure you realize that as well haha)


I would love to get some stock n/a cams because they are like right between stock det cams and a small aftermarket cam.

I'll make a few emails for you, I've got a ton of SE-R friends. I assume you want the B13 cams.

I ran my SR with HKS 264 step 2 in/ex, and s14 T28 at 14psi and other mods w/ stock injectors, maf and ECU. No tuning at all and that thing fucking RIPPED, never had a problem and the motor is still running in someone elses car today.

How your car hasn't/didn't blow up is beyond me. I know on a T25 setup, running cams almost immediatly pushes all of the surrounding bits to their maximum safe level, at stock boost. Your car is certainly not the norm hehe.

mct3351
03-07-2011, 07:59 AM
If you run the stock ecu/tune, stock injectors and stock maf with no more than ~0.6 bar of boost you will be perfectly fine. That is assuming all else with your build is in order.

The maf will compensate for the slighly larger mass flow rate at the same load/intake manifold pressure. The cams will certainly shift your peak VE but the MAF EFI will compensate for this as long as you remain safely within the injectors & maf max flow rate (conservatively 0.6 bar w/ cams). It will certianly not be optimized for peak performance but neither is a stock tune for stock cams. FYI the stock tune is quite conservate timing wise.

4x4le
03-07-2011, 08:16 AM
cody,
You know I lost oil pressure at a drift event right?????? Broken sump.

I guess ill never be able to do a comparison for you on that engine. Also that dyno graph come to find out was scewed a little on the up side as the calabration was off or something and I never got to re dyno. He said I was probably making 15-20 less whp but its impossible to tell. Im upset that engine isnt around anymore to do further testing on because it was a damn good engine to me.

Anyways I did just get some cams lined up for myself. They may not be exactly like what you would want to see but I got a n/a high port intake (248* 10mm) and a gti-r (248* 10mm) exhaust.

Really not trying to thread jack here but in case you havent heard about the engine Im building right now.

Custom weisco 90mm 10:1 compression pistons with valve reliefs (like I need them lol)
k1 92mm crank and k1 rods
darton sleevs
cosworth hg
isis t3 log
sound performance quick spool valve (operated by greddy type s)
twin scroll t3 .82 turbine housing for my 2871r (externally gated)
gismo ebc (rpm dependent boost) I might try to over boost for some more tq too...
And lots of e85, Im sure im missing things but you get the point. Have faith.


mct, did you get your ecu figure out. Make sure to pm me when you find something

codyace
03-07-2011, 09:55 AM
cody,
You know I lost oil pressure at a drift event right?????? Broken sump.

Oh yuck! That's one of those things that you always hear about, but never really know who's had it happen :( Sucks! Were you using a S14 pickup?

cody,
I guess ill never be able to do a comparison for you on that engine. Also that dyno graph come to find out was scewed a little on the up side as the calabration was off or something and I never got to re dyno. He said I was probably making 15-20 less whp but its impossible to tell. Im upset that engine isnt around anymore to do further testing on because it was a damn good engine to me.

What sort of dyno were you on? Regardless the car still made some great power...especially for the simplicity of it!


Anyways I did just get some cams lined up for myself. They may not be exactly like what you would want to see but I got a n/a high port intake (248* 10mm) and a gti-r (248* 10mm) exhaust.

Yup, B13 cam set :D That's a proven N/A setup for sure, also undetectable in inspections hehe. I still wish you'd throw a 256 behind it at a minimum tho ;)

Edit: I was an idiot haha.

Really not trying to thread jack here but in case you havent heard about the engine Im building right now.

And lots of e85, Im sure im missing things but you get the point. Have faith.

Nice stuff! Since when were the T3 '2871' exhausts twin scroll? Damn been a long time since looking into that stuff hehe. Should run pretty damn good! Interesting choice on the stroker there, that's gonna be really neat to see!

PS: The spool valves work great :D

4x4le
03-07-2011, 10:40 AM
I have a s14 pickup now. I thought I was safe because mine was fine and I have the greddy pan, I guess I was wrong...

I use a dyno dynamics

I had no idea you could use an intake cam in place of the exhaust cam like on ka's. Ive never built an engine because Andy is so good at it, why not put him to (more) work?

Atp sells twin scroll housings and even complete 2871r's with the twinscroll housing installed for the normal 2871r price

Thats the only place I can find them, and they are v band out too.

Pretty much I feel like the power my old setup made was nasty after 4k so with cams I just would have made it nastyer up top but weaker down low. So this build I wanted to make it nasty everywhere.
I had damage on one of my cams and I really wanted to keep the stockers in there and then maybe try some different cams later on since I can use the dyno whenever I want. I decided to just play it safe and do a mild setup. As long as the car is fast there is no way Ill open it back up untill I have to.

codyace
03-07-2011, 12:34 PM
I have a s14 pickup now. I thought I was safe because mine was fine and I have the greddy pan, I guess I was wrong...

No shiz! Hmmmnow you're scaring me to change to an S14 one too :hyper:



I had no idea you could use an intake cam in place of the exhaust cam like on ka's. Ive never built an engine because Andy is so good at it, why not put him to (more) work?
I goofed!

I had the Altima's in mind when I said that (considering that is what I did to my turbo altima, twin intake cams). The B13 (as you pointed out) needs the 248 intake cam and that GTiR Exhaust 248 cam to work haha. Doh!


Atp sells twin scroll housings and even complete 2871r's with the twinscroll housing installed for the normal 2871r price

Nice stuff! It's been such a long time that I've honestly not kept track of it hehe. Maybe if my current setup pukes I"ll change it up?!?! Then again I'd probably go V8 :/

KaminaSan
03-07-2011, 01:48 PM
If any car I'd love to see a direct comparison on, it would be your car. Obviously it may be a unrelated type graph as you have the ability to tune it over some of the MAF guys, but I'd love to see your car with some cams in her.

To me, there is a fine line of response vs. average power...me being a 'spool it as fast as you can guy' can even agree that at times it's not worth the extra low end (especially as my car is a track based car anymore) if you can make much more midrange torque and top end power, as that's where the car is most of the day. With having the dyno around, anymore I'm not even looking at peak or early times at this rate, only average power and then over time frame...which is something MANY do not even look at...(and Im' sure you realize that as well haha)



I'll make a few emails for you, I've got a ton of SE-R friends. I assume you want the B13 cams.



How your car hasn't/didn't blow up is beyond me. I know on a T25 setup, running cams almost immediatly pushes all of the surrounding bits to their maximum safe level, at stock boost. Your car is certainly not the norm hehe.

Well, that's enough for me. Either I get a powerfc with base tune for break in, or I don't put in new cams.

Thanks for the input guys.

aNskY
03-13-2011, 09:01 PM
why would you build an SR if youre "mostly interested in torque"?

KaminaSan
03-13-2011, 09:06 PM
why would you build an SR if youre "mostly interested in torque"?

Because the SR has huge torque with it's powerful v4 20 liter engine.

On a serious note though: I'm staying with SR because my car is wired for SR, and I live in cali, and don't want to deal with an RB overheating on me, nor do I feel like paying 3500 to get an RB/everything needed, and only have a stock engine, vs having a fully built SR for 2 grand less.

What I should have said was: 'what cams would be good for creating lower end power/torque'

aNskY
03-13-2011, 09:42 PM
What I should have said was: 'what cams would be good for creating lower end power/torque'

stock

i think you should sell the sr and get a SBC. :)