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Discussion Starter · #1 ·
I am hoping to get some insight from you all regarding the best modification path.. I am in the process of planning my approach, and though I believe I will eventually go with a magnacharger, I am going to start with some NA stuff..

I spend most of my time in the 2k - 4k rev range, and therefore I want my mods to improve the mid-range area. I am considering an intake, H/C, headers and exhaust. I'm figuring the "breathing" components provide the greatest improvement in the high RPM range, but is there a cam which anyone has utilized which provides the greatest improvement in the mid-range area?

Also, am I correct about my assumption regarding the headers, exhaust, intake and heads providing greatest benefit up high?

I am just starting to learn about tuning a non-turbo charged vehicle, and any insight is greatly appreciated. Also, any suggestions about improving the mid-range pre-FI is absolutely appreciated. :cheers:

Ben
 

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I dont know much about cams, but I know that a Roots-type blower will give you massive power between 2k-4k, the centrifical Typer Supercharger( ex. vortec,ATI) will take a power away up to 3000rmp -3500rmp and then increase all the way up. And turbo will give you both what both types of SCs I just mentioned. I hear headers ect with a good tune will give you all around the RPM range :thumb:
 

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You want a cam with minimum valve overlap for off-idle throttle response. However, the heads are so efficient on these cars and with a quality EFI tune, you can get fairly radical and still maintain great street manners/mid-range TQ.

Knowing that you are going to go with a Magnacharger down the road, cam selection is critical right now, unless you want to swap out the cam later on.

I would call John Page at 21CMC and see which cam they use in their Magnacharger applications. Knowing LPE/21CMC, I would be shocked if this is a "large" cam. Since it is designed for something that operates efficiently in the typical rev range of a stock Z06, I am willing to bet it would be a very decent N/A camshaft as well. I do not have specs on it, so I cannot comment there.

Whatever you do, _make sure_ whoever helps you choose your cam knows your needs. Your needs/wants are not typical of Z06 owners. Most want max power/tq and that means a bigger cam that allows the engine to be efficient near 7000rpm. So repeat your desires over and over and over, so they get the message. :)
 

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COUTO1981 said:
the centrifical Typer Supercharger( ex. vortec,ATI) will take a power away up to 3000rmp -3500rmp and then increase all the way up.
Do you have dyno charts that prove this point? You're saying that a centrifugal blower will make _less_ power than stock up to ~3000rpm? If that's what you're saying, then that's totally false unless the tuning was done poorly.

I have run centrifugal blowers for well over a decade (Vortechs) on a number of different vehicles (3). They do not make _as much_ power as a positive displacement blower in the lower rpms, but they still make good gains down low. Maybe not tire-spinning power, but that can be an advantage when you're seeking traction.

As an example, my little 331 cubic inch SBF made 400rwtq @ 2700rpm with the Vortech...596rwtq @ 4900rpm. However, this combination was optimized through careful research of cam selection and proper tuning (by me) and not utilizing stock parts. The problem with centrifugally blown applications is that they are not cammed optimally and this leads to very lazy low-end power... but still, its higher than _stock_.
 

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WA 2 FST said:
Do you have dyno charts that prove this point? You're saying that a centrifugal blower will make _less_ power than stock up to ~3000rpm? If that's what you're saying, then that's totally false unless the tuning was done poorly.

I have run centrifugal blowers for well over a decade (Vortechs) on a number of different vehicles (3). They do not make _as much_ power as a positive displacement blower in the lower rpms, but they still make good gains down low. Maybe not tire-spinning power, but that can be an advantage when you're seeking traction.

As an example, my little 331 cubic inch SBF made 400rwtq @ 2700rpm with the Vortech...596rwtq @ 4900rpm. However, this combination was optimized through careful research of cam selection and proper tuning (by me) and not utilizing stock parts. The problem with centrifugally blown applications is that they are not cammed optimally and this leads to very lazy low-end power... but still, its higher than _stock_.

ok, I dont have anything to prove that with, maybe I went up too far to 3500rpms, maybe its more like 2500rpm, that Im sure. If you get a descriptive technical explanation of what the centrificul blower does it explains very clear the point that it takes a bit of power from the bottom...

Maybe they're wrong who knows, but one thing is for sure when I had it on my Mustang after a Very good tune, you could tell night and day diffrence between stock, and on the very bottom it was WAY less power but passed 3000rpm it just shoot up quicker then he!! when compared to stock mustang...

your 331 made good power, but I dont think a 331 is stock so it could be massaged to make power anywhere it would be put to make it, I say if you took the blower out it would make 410rwhp at 2700rpms. You compared apples to oranges :NoNo: , I compared cars back to back and it proved what the Supercharger makers and experienced tell everyone about...

My only proff is that I drove my mustang for 2 years and then with the blower it showed less power down low, But it was perfect power band IMO, then I drove another stock GT and It had alot more power down low but nothing compared to the power above, It was like it was a totally diffrent and way Faster car with the Vortec :thumb:
 

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BTW.. on top of all those scientific explanation why the Centrifical takes power from the bottom but adds alot up top, there also on more major clue, boost on the Centrifical build up, boost on the roots-type spike to max on low rpms. :yeadog:

and I see again your 331 was major built up to make that power, a fact is that the centrifical does take power down low, maybe way down low but it does
 

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You know what... you don't understand the technical reasons, so I am not going to get into this debate with you. You are wrong. Period.

A _stock_ Mustang with a centrifugal blower does _not_ lose power at 2000rpm compared to the same motor N/A. Not a 5.0, not a SOHC 4.6, certainly not a DOHC 4.6.

I'm not debating the efficient powerband of the blower. I have a very good understanding of that, thank you. I understand full well that boost builds with rpm in a centrifugal application moreso than a positive displacement (roots/screw) setup. But even 2-3psi at 2000rpm will make more HP/TQ than a N/A setup all things being equal (cam, exhaust, intake, etc).

I'm not wasting any more of my time debating with you (as I have on other threads). You're out of your league on this one. If your Mustang made less power down low w/ the blower then there's another reason for it.

My point has, and will always be, that people who say you can't make decent bottom-end and mid-range with a centrifugal setup don't have a clue what they are talking about. You mention "supercharger makers"... find me one blower company that says their blower makes _less_ HP/TQ than a stock N/A setup. Keep looking. You won't find one. You didn't prove anything. Find someone here with an ATI or Vortech on a stock LS6 and see if they _lost_ HP in the powerband. You won't find one.

And don't go accusing me of making an apples to oranges statement. You have _no clue_ about that 331 application. None. No it would NOT make 410rwtq at 2700rpm if I took the blower off. I designed that entire combo around the blower itself...lower CR, proper cam selection, large tube headers, etc. It would have run like crap without the blower (although it would have made more power than a stock 5.0) b/c airflow velocity would have been horrible.

Beyond that particular motor I built, I have run centrifugal blowers on several stock applications. So I have my own back-to-back testing, and never once with the engine tuned correctly was there a _loss_ in power or torque at full throttle.

ANY blower will rob some power just standing there spinning as it takes engine power to spin the blower. I understand that. And on different applications the low end _gains_ may not be as significant as one would like for a given application. But your earlier statement was completely wrong and misleading. With a torquey motor like an LS1/LS6, you will see gains even at low rpms with a centrifugal blower.

I could tell you why sometimes people may "feel" a loss or there is legitimately a loss, but I'm not going to take the time to explain it here b/c it has nothing to do with the original poster's question.

***It is possible for there to be _slightly_ less tip-in throttle response at low rpm (like 1000-1200rpm) _when you're not in boost_.*** Again, most of this is due to the fact the blower takes power to spin, but this is typically very easy to overcome with _good_ tuning. But this isn't what you were saying or implying in your original post which was ... "less power to 3000-3500rpm".

I'm happy to be quiet and _listen_ when I don't know what I'm talking about. You may want to consider the same before spreading blatant misinformation.
 

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WA 2 FST said:
You know what... you don't understand the technical reasons, so I am not going to get into this debate with you. You are wrong. Period.

A _stock_ Mustang with a centrifugal blower does _not_ lose power at 2000rpm come . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . be quiet and _listen_ when I don't know what I'm talking about. You may want to consider the same before spreading blatant misinformation.
:cheers: You are correct, sir! Should we pull up some dyno graphs for some backup, or is it not worth bothering?
 

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Brandon, some of that might be great comparison info for the original poster, although it sounds like he has his mind made up on a H/C setup and a Magnacharger later (nothing wrong with this choice might I add).
 

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Nothing wrong with the choice you have made, except that blown cars dont really need big dollar heads on them.

From your original post on the H/C route I would suggest going the AFR 205 route with a mild blower camshaft...But if it were me I would not spend that much money on the heads if I were going to go blown later.

LT headers will most definately help your low end torque, and the FAST intake is a pretty amazing product considering I have not seen it hurt low end torque and adds on top end also.

If I were going to stay N/A I would say afr 205s, fast 78mm intake and ported Tb, LG LT headers, UD pulley, and a mild camshaft that AFR reccomends for those heads (I think they use like a 220/224?).

BUT for blown, I would say stock heads, stock intake (none needed for maggie), LT headers, mild blower camshaft and thats all.

All just my .02

WA 2 FST said:
You want a cam with minimum valve overlap for off-idle throttle response. However, the heads are so efficient on these cars and with a quality EFI tune, you can get fairly radical and still maintain great street manners/mid-range TQ.
Wes, can you talk a little more about camshafts? I know you know your stuff. I have always read that tight LSA camshafts (More overlap) will yeild lower RPM peaks...Maybe this is just HP...Does more overlap bleed off needed cylinder pressure for less back pressure and torque? What would the torque curve look like for a 224/224 .563/.563 on 112 as compared to the same camshaft on 114 LSA?

I know that blowers do not like valve overlap (bleed off boost) and generally are a traditional split (more exhaust duration than intake duration. Seems like a 220/228 .563/.581 on 115 or so would be a nice blower cam...Just spurting out stuff at this point.
 

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Discussion Starter · #11 ·
WA 2 FST said:
Brandon, some of that might be great comparison info for the original poster, although it sounds like he has his mind made up on a H/C setup and a Magnacharger later (nothing wrong with this choice might I add).

I do like the torque and power curve of the magnacharger.. if only it could go with a stock hood.. I had a stage III audi S4 previously and love the stealth aspect of that vehicle.. SOOOOO boring outside, but was a nice surprise to unleash..

Anyway, I use the Z06 on most nice days, but unfortunately I don't have the opportunity to wind it out often, so wacked out power in the middle of the RPM range is the most fun for me..

Sounds as if I need to contact a tuning shop to talk about options, especially if my needs are a little out of the ordinary.. Though I occasionally get into the 5k+ rpm range, thats the minority of the time and I would rather enjoy gut twisting power as much as possible..
 

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Discussion Starter · #12 ·
will intake hurt?

niphilli said:
Nothing wrong with the choice you have made, except that blown cars dont really need big dollar heads on them.

From your original post on the H/C route I would suggest going the AFR 205 route with a mild blower camshaft...But if it were me I would not spend that much money on the heads if I were going to go blown later.

LT headers will most definately help your low end torque, and the FAST intake is a pretty amazing product considering I have not seen it hurt low end torque and adds on top end also.

If I were going to stay N/A I would say afr 205s, fast 78mm intake and ported Tb, LG LT headers, UD pulley, and a mild camshaft that AFR reccomends for those heads (I think they use like a 220/224?).

BUT for blown, I would say stock heads, stock intake (none needed for maggie), LT headers, mild blower camshaft and thats all.

All just my .02



Wes, can you talk a little more about camshafts? I know you know your stuff. I have always read that tight LSA camshafts (More overlap) will yeild lower RPM peaks...Maybe this is just HP...Does more overlap bleed off needed cylinder pressure for less back pressure and torque? What would the torque curve look like for a 224/224 .563/.563 on 112 as compared to the same camshaft on 114 LSA?

I know that blowers do not like valve overlap (bleed off boost) and generally are a traditional split (more exhaust duration than intake duration. Seems like a 220/228 .563/.581 on 115 or so would be a nice blower cam...Just spurting out stuff at this point.

As I'm not ready to go the FI route yet, what it your thought on something for fun in the interim? FAST intake (which I have to research) and long tube headers? Any benefit to adding a cam suitable for the magnacharger pre-FI??
 

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That's cool about your S4. My brother has a Stg 2 setup done by Sportech in Colorado and his puts out 400AWHP. It is definitely quick.

I would do headers, high-flow cat pipe, cat-back and a cold-air intake right now. Get it tuned and you should be ~385-390rwhp. This may not be as much as you want, but niphilli has a good point about spending $$ on aftermarket heads (and certainly an intake manifold) if you're going to go with the Maggie blower later on. The Mag blower is on the smallish side anyway to feed a 346ci motor, so adding freer flowing heads isn't going to help much over your LS6 heads. To take full advantage of them, you really need a blower that pushes more air. This isn't just my opinion, but also the opinion of several reputable tuners.

Niphilli, I'm going to send you a PM regarding your ?s.
 

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WA 2 FST said:
That's cool about your S4. My brother has a Stg 2 setup done by Sportech in Colorado and his puts out 400AWHP. It is definitely quick.

I would do headers, high-flow cat pipe, cat-back and a cold-air intake right now. Get it tuned and you should be ~385-390rwhp. This may not be as much as you want, but niphilli has a good point about spending $$ on aftermarket heads (and certainly an intake manifold) if you're going to go with the Maggie blower later on. The Mag blower is on the smallish side anyway to feed a 346ci motor, so adding freer flowing heads isn't going to help much over your LS6 heads. To take full advantage of them, you really need a blower that pushes more air. This isn't just my opinion, but also the opinion of several reputable tuners.

Niphilli, I'm going to send you a PM regarding your ?s.


I agree with the above.

If you really want, get some umph, before getting blown. I would suggest a forged 382 short block at 10.5 compression with ported stock heads and a .576/.576 234/234 cam. The comment on the heads is about right on a blown application. I would really look at the Kenne Bell Whipple at that point. It should out in about four months.
 

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Wits-Z said:
As I'm not ready to go the FI route yet, what it your thought on something for fun in the interim? FAST intake (which I have to research) and long tube headers? Any benefit to adding a cam suitable for the magnacharger pre-FI??

For the interim I would start with a good set of LT headers (Probably LG or Kooks 1-3/4"). A good aftermarket air intake, and a tune by a reputable tuner. Leave the intake manifold and heads on the shelf if the blower is still in the equation. If the blower goes out of the equation go with AFR 205 heads with a good camshaft matched to the heads.

I am probably going to get cruicified in this forum for saying this in the power adder forum, but I am not a big fan of FI LSx cars if you are not going to modify them internally. The head and cam developments on these cars is amazing. You can get just about as much out of a HC LS6 these days as a Maggie with conservative boost (stock internal), and IMHO the H/C route will provide better service, gas mileage.... On the low end torque route I would be interested to see a dyno graph of a full bolt on AFR/cammed LS6 low end torque VS a maggie/blower cam low end torque...My thought is that the maggie will make more, but not a *Ton* more. Ok OK, I am way off track now.

*EDIT* - May have to eat my words:
C5neb- IC Maggie/blower cam:

jwschmidt:
maggie 3.3 pulley:


Very hard to argue with the midrange on these setups, I am still not a fan of blown with stock internal LSxs, but an intercooled maggie at low boost with a blower cam and the supporting bolt ons will probably live a good long while.
 

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Wits-Z said:
I am hoping to get some insight from you all regarding the best modification path.. I am in the process of planning my approach, and though I believe I will eventually go with a magnacharger, I am going to start with some NA stuff..

I spend most of my time in the 2k - 4k rev range, and therefore I want my mods to improve the mid-range area. I am considering an intake, H/C, headers and exhaust. I'm figuring the "breathing" components provide the greatest improvement in the high RPM range, but is there a cam which anyone has utilized which provides the greatest improvement in the mid-range area?

Also, am I correct about my assumption regarding the headers, exhaust, intake and heads providing greatest benefit up high?

I am just starting to learn about tuning a non-turbo charged vehicle, and any insight is greatly appreciated. Also, any suggestions about improving the mid-range pre-FI is absolutely appreciated. :cheers:

Ben
Call Geoff at Thunder Racing regarding their T-Rex cam. Very powerful midrange cam - don't know the specs. If what you are looking for is an excellent HC package, with mid-punch for the street, they can help you. 225-754-7223. Tell Geoff that "Thor" sent you.
 

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ScDFACHE said:
Call Geoff at Thunder Racing regarding their T-Rex cam. Very powerful midrange cam - don't know the specs. If what you are looking for is an excellent HC package, with mid-punch for the street, they can help you. 225-754-7223. Tell Geoff that "Thor" sent you.
Definately call Thunder Racing, top notch orginizaton, but I SERIOUSLY doubt that they will reccomend the Trex for the street...It is HUGE.
 

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Discussion Starter · #18 ·
thanks a lot for the thoughts..

I'm make a few calls.. I'm glad to get the insight, though, as it sounds as if I don't want/need to mod too much in the interim if I'm looking FI in the near future.

Am I correct that if I FI on the stock engine, if anything goes wrong, I can go forged at that time anyway? Any benefits to going forged pre-FI if I don't mind being "laid up" in the event the stock engine components can't handle it? (still thinking in stages)..

Thanks.

Ben
 

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Wits-Z said:
I'm make a few calls.. I'm glad to get the insight, though, as it sounds as if I don't want/need to mod too much in the interim if I'm looking FI in the near future.

Am I correct that if I FI on the stock engine, if anything goes wrong, I can go forged at that time anyway? Any benefits to going forged pre-FI if I don't mind being "laid up" in the event the stock engine components can't handle it? (still thinking in stages)..

Thanks.

Ben
I dont have a bunch of experience here but I am pretty sure it is the pistons that usually go...Just depends on how much it damages the sleeves when it pops...I would think you could probably just get away with a cleanup bore job (347CI) and forged slugs. If you keep the boost at 5-6lbs with an intercooled maggy and a GOOD TUNE you probably will not have any problems.
 

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The biggest issue with going blower/turbo on a stock motor is the relatively high compression ratio of the stock motor. This is a problem moreso than even the hypereutectic pistons. 10.5:1 CR does not lend itself to running much boost at all. The hyper pistons typically get hurt b/c there is detonation involved which is due to running too much static compression and not high enough octane for your fuel source. There _is_ such a thing as inaudible detonation, and you are pushing the envelope in many cases with even 6-7psi on a 10.5:1 CR motor. Sometimes you can get away with it for awhile by retarding the ignition timing a lot, but then you're hurting the power potential, too.

So going forged beforehand is good b/c you'd also lower the base CR of the engine (9.0:1 or even slightly lower). This way you can really spin the blower, make 10-12+psi on 93 octane and never have an issue... and you'll make a LOT more power than 6-7psi w/ 10.5:1 CR b/c the airflow volume through the engine is much greater. :)

The only issue here with the Magnuson blower is it is just not big enough (and therefore efficient enough) to make 10-12psi on a 346ci motor with a good induction/exhaust setup. It just cannot flow the kind of air you need to make that worthwhile. So with the I/C Mag blower, 5-6psi is about it, and as niphilli stated before you should be ok with the stock internals for a long time. I would definitely vouch for the 21CMC Magnuson blower cam. From all the dyno charts I've seen it really helps keep the power up to 6500rpm.
 
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