Darkane

Ive been wondering for a bit here. I have a built D series (stock sleeves) coming together in the next month here. Im trying to Choose a cam here but kinda stuck. I have seen excellent results with Comp cams stage 2 but with my lower CR (9:1) will Larger primarys lower the RPM of which the turbo spools? In theory it should. More air being pushed even if it is over cammed.. Question is: Which D series cam lower than a stage 3 would have an oversize Primary for better spool AND would it actually work with 9:1CR?

Setup:

D16A6 bottom stock sleeves
SRP 9:1 75.25mm
TunerToys Eagle style Rods
Stock crank and OEM bearings.

D16Z6 head
3 angle valve Job
Supertech Nitrate stainless valves - STD size
Cam = ?

Bolt ons
Skunk2 Pro series Intake mani
2.5/3.0" exhaust. - not certain yet

Turbo will be (i sure hope so) GT28RS. Anythign else I forgot to add just let me know. Looking for 300WHP and a fat 4.5-8k Powerband.

Thanks.

dornon13

you sure the RS will get 300 on a D? i might look into the gt2871r

mrbsponge

primary lobe will play a role in turbo spool, what is also important to look at is lif and duration. to a point N/A cams can actually work kinda well, such as the ITRs in B series

Civicman86

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">you sure the RS will get 300 on a D? i might look into the gt2871r</TD></TR></TABLE>

IM pretty sure the RS can easily get 300 on a d series. Im running 9lbs and based on injector duty cycle and butt feel, im making aroudn 230whp. RS hasnt even opened up yet.

Darkane

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 &raquo;</TD></TR><TR><TD CLASS="quote">you sure the RS will get 300 on a D? i might look into the gt2871r</TD></TR></TABLE>

good Question.. I hope so. With the addition of Valves, cam, valve train and Intake Manifold I dont think i will have problems hitting 300 maybe a tad more. I want to stick with the RS for the quick spool.

If i can find a cam with lets say a Stage 3 primary(outa VTEC) and maybe a stage 1 or 2 Secondary (in VTEC) I think i could gain some power under the curve and get that turbo spooled quickly. no one knows of a cam such as this eh? I know im not getting a custom grind but Im gonna look at some profiles and try to figure it out. ANybody got any recomendations? Thx.

dornon13

let us know how it goes i know alot of people are interested on that subject

Darkane

^^ Will do for sure.

EDIT: so I found some wicked info to share here..

Couldnt find STOCK D16Z6 specs but D16Y8 will be close enough:

Stock D16Y8 Cam
Adv Duration Duration@.050
___Int/Exh__Int/Exh_Lobe Sep_Gross Lift
PRI..211........183........115..........300
SEC.215........187........113..........319
VT...247........217........114..........397
EXH.235........204........110..........370

So there is that with all the lobe profiles. Here is Comp/Zex stage 2 for D16Z6:

Comp Cams and Zex #59300
Adv Duration Duration@.050
___Int/Exh__Int/Exh_Lobe Sep_Gross Lift
PRI..232........190........111..........300
SEC.236........194........115..........310
VT...260........220........107..........455
EXH.268........216........111..........430

So if we compare for a minute the primary lobe of the stock cam AND the stage 2 both have the same 300 gross lift. The secondary of the stock cam actually is greater than the stage 2 by 9. 310 vs 319. Interesting..

Duration is another story.. Primary Advertised is 211 vs 232 and secondary 215 vs 236. Now would duration on the small lobes move more air and spool the turbo faster than lets say a Crower stage 2 Turbo cam? I cant find specs on the turbo cams small lobes but i assume they have more lift than the stocker. All i want in a cam is too have higher lift AND duration on the small lobes for spool but its looking glim I shall update if i come across more info.

Taken from: http://turbod16.com/viewtopic.php?t=2085




Modified by Darkane at 11:27 PM 3/20/2006

Darkane

up. Added info.

ELSpool

Your missing one big thing that companies tend not to publish, ramp rate. Alot of aftermarket companies put very aggressive ramp rates on D-series cams. This will play a big role in spooling a turbo as well. From the cams I have used on my Y8, I find the big lift, high duration and aggressive rate rates to spool turbos faster, but don't carry peak tq out into the high rpm range. (which is very controversal because thats what they were designed for, but these are my findings) I found the stock Y8 cam to cause slower spool times, but carried peak tq well beyond my Comp Cam/Zex stage 2 cam. I'm going to try an inbetween Crower cam this year, with a much larger IM(Golden Eagle) than my Skunk2, and see if I can get the best of both worlds. And again, alot depends on your setup and what your goals are with the car.

Darkane

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">Your missing one big thing that companies tend not to publish, ramp rate. Alot of aftermarket companies put very aggressive ramp rates on D-series cams. This will play a big role in spooling a turbo as well. From the cams I have used on my Y8, I find the big lift, high duration and aggressive rate rates to spool turbos faster, but don't carry peak tq out into the high rpm range. (which is very controversal because thats what they were designed for, but these are my findings) I found the stock Y8 cam to cause slower spool times, but carried peak tq well beyond my Comp Cam/Zex stage 2 cam. I'm going to try an inbetween Crower cam this year, with a much larger IM(Golden Eagle) than my Skunk2, and see if I can get the best of both worlds. And again, alot depends on your setup and what your goals are with the car.</TD></TR></TABLE>

Interesting stuff. I wonder if the Duration of the vtec Lobe is 'bleeding' boost out. It is wierd how the stock cam carries a further torque curve. Im toying with the idea of doing a custom grind with some simple specs. Higher lift AND duration (stock ramp angle) on the primary and secondaries and Some added lift OR duration on the VTEC lobe(over stock). Im going to contact a guy in BC about this. He does custom grinds.

Or if anyone on HT does a custom turbo re-grind let me know.

EDIT: Has anyone tried setting VTEC to engage Before the majority of the spool? Say 3800RPm on the D series. stock 5200. I wonder if that would choke the motor or give the turbo the air it needs to Suddenly spike and hit max boost? Comments.

https://honda-tech.com/zerothread?id=1371500 In this thread It seems the turbo started spooling and the motor hit VTEC around 5800rpms. at 6200 the turbo was fully spooled. I wonder If that vtec was set at 5k RPM what would happen. Theres is also a kind torque spike for a few hundred Rpms after as well then it levels a little.


Modified by Darkane at 4:13 PM 3/21/2006

dornon13

im sure the tuner moved the vtec engagement to the most advantageous position....too low or too high you will get a dip in power

what about a vtec killer type cam for a sohc