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Discussion Starter #281
Bruce,

I read a recent post you made for another member here inquiring on a cam recommendation for his 2016 V.

You mentioned the following at the end:

-assuming the head flows 368 cfm on the bench-
Intake lobe for a 2.165" valve will need to be about. . .
1) 228° at 0.050" of lifter rise to hold power to 6,712 rpm's.
2) 232° at 0.050" of lifter rise to hold power to 6,830 rpm's
3) 234° at 0.050" of lifter rise to hold power to 6,880 rpm's
4) 238° at 0.050" of lifter rise to hold power to 7,007 rpm's

Again, the less the cylinder head flows from that 368 cfm
value, the 'Larger' your cam duration will need to be.

My question to you is this:

My cam specs are as follows: 233/249 .630/.600 120+4

My tune commands shifts at 6,800 rpm. Currently I'm seeing 12PSI and am on E-85. Heads are ported LSA castings with larger valves, 2.180/1.6.

Now, the following flow numbers are on a 4.065 hole, my holes are larger (giggity) 4.125. Frankenstein said the numbers would be a little better, but not by much. With the data here, would it be safe to say that 6,800 is not too high of an RPM to shift at? I'll be getting the car on a dyno soon. Just optimizing a few things.....my intercooler fluid blew out all over the road today. Some hose in front of the engine let go....I'll be investigating that in the morning.
 

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Bruce,

I read a recent post you made for another member here inquiring on a cam recommendation for his 2016 V.

You mentioned the following at the end:

-assuming the head flows 368 cfm on the bench-
Intake lobe for a 2.165" valve will need to be about. . .
1) 228° at 0.050" of lifter rise to hold power to 6,712 rpm's.
2) 232° at 0.050" of lifter rise to hold power to 6,830 rpm's
3) 234° at 0.050" of lifter rise to hold power to 6,880 rpm's
4) 238° at 0.050" of lifter rise to hold power to 7,007 rpm's

Again, the less the cylinder head flows from that 368 cfm
value, the 'Larger' your cam duration will need to be.

My question to you is this:

My cam specs are as follows: 233/249 .630/.600 120+4

My tune commands shifts at 6,800 rpm. Currently I'm seeing 12PSI and am on E-85. Heads are ported LSA castings with larger valves, 2.180/1.6.

Now, the following flow numbers are on a 4.065 hole, my holes are larger (giggity) 4.125. Frankenstein said the numbers would be a little better, but not by much. With the data here, would it be safe to say that 6,800 is not too high of an RPM to shift at? I'll be getting the car on a dyno soon. Just optimizing a few things.....my intercooler fluid blew out all over the road today. Some hose in front of the engine let go....I'll be investigating that in the morning.
Wow, those heads really begin to 'Kick Ass' around 0.500" lift..:D

If I average the flow between 0.500" lift and 0.600" lift
I come up with a peak hp rpm of 6,803 rpm's.

That makes sense to me anyhow, as your cam will only
lift the intake valve a max of 0.630" at peak lift, and
that translates to an 87% effective / mean lift of 0.541".

On some NA Engines this little formula that I bang out on
my handheld calculator falls short by a couple hundred
engine rpm's.

But in most all cases, the NA Engines were also not InFlow
restricted as are our engines. Some just ran better in an
overall sense on the engine dyno with a smaller carb
than what we would have liked to use to make max HP.

We built and ran one 434 cid that kind of fit what I am
speaking about, as it just liked the smaller carb.

The cam had a duration of 280° and a valve lift just under 0.800".

It should have held peak power to 8,176 rpm's.
It ran out at ~7800 rpm's.

It should have made around 890 fwHP,
but ran out at about 878 as I recall.

Peak torque pretty much came in on both the peak
torque number, as well as the rpm we projected.

Will be interesting to see how yours does,
especially if you run it with the 108mm TB,
and a good blower using E85..:D

Cheers
 

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Discussion Starter #284
108 is port matched and on. Few things to button up then I’ll start her up. Will also have to buy a coupler with a few more degrees of bend to it so I don’t force it out-of-round.
 

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Discussion Starter #287
Pretty sure the 102 blade won't open all the way with a stock snout.
It won’t. 30 min of grinding and sanding and you’re GTG.
 

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Discussion Starter #288 (Edited)
Anybody drill out the vacuum port on the valley cover? I bent mine down to clear the new LSA snout I'm helping R&D and it pulled out. Upon initial inspection, there's a small block off plate in there which restricts vacuum inlet to the crank case. I went ahead and drilled it out from about 1/8" to 5/16" which is just about the width of the ID on the port. My hope here is that it will increase air inlet from the CAI into the valley and improve my MM Wild catch can's performance. Since I run E85 all the time, it's nice to get the crank case vented well and remove those bad gasses.

I wish I had taken pictures of the restrictor inside the tube, but here is what I'm talking about.

Also, cleaned under the hood a bit. Now all's I need is a Maggie to complete the package. :)
 

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My 102 fits and opens all the way. Stock snout
Interesting, as the factory 87mm throttle body uses a gasket that is approximately 100mm in diameter- are you sure yours wasnt ported?

Or are you using a spacer that pushes the blade further forward, effectively increasing clearance?

If it does fit I am truly surprised- but you also have a decent ledge on the snout creating turbulence when the blade does open.

Still worth hogging it out as the TB and snout are typically the flow bottleneck for the intake.

Sent from my SM-G965U using Tapatalk
 

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Interesting, as the factory 87mm throttle body uses a gasket that is approximately 100mm in diameter- are you sure yours wasnt ported?

Or are you using a spacer that pushes the blade further forward, effectively increasing clearance?

If it does fit I am truly surprised- but you also have a decent ledge on the snout creating turbulence when the blade does open.

Still worth hogging it out as the TB and snout are typically the flow bottleneck for the intake.

Sent from my SM-G965U using Tapatalk
Positive. I was suprised also. No spacer. Just a 2mm gasket. To help it seal as it does grab all corners of the o ring.
 

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Positive. I was suprised also. No spacer. Just a 2mm gasket. To help it seal as it does grab all corners of the o ring.
Throttle blade axis to gasket face is an important dim when considering this fit...its not all that surprising that it actuates freely. The TB are likely designed, increasing that dim as much as practical, to ensure a broader use spectrum.

Now if the throttle had a square blade on it (profile didnt change with this dimension), scrapy scrape scrape.
 

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Discussion Starter #293
So, don't drill out the vacuum port on your valley cover. Well, not if you have a MM Wild catch can anyway. I was having rich idle issues and my car was getting too much air and not wanting to coast down. To correct my mistake I put in a restrictor on the vacuum AN fitting. Fixed all my issues. LOL.

Freezing rain here today....no full throttle for a while. :)
 

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Wow
 

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Discussion Starter #296
Yeah, the Kong 2650 may be the direction I take down the road. Will be interesting to see how the stock and ZL1 intercooler bricks perform with this thing. The 2650 Magnuson made for their LT4 application has intercooler bricks 10X the size of our stuff. That's got me skeptical for sure. On stock cube applications where the blower RPM will be lower, it may work fine, but who knows. We will be seeing these on the dyno soon and in the spring out at the tracks.

Hands down, cool blower though.
 

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Discussion Starter #297
So far the 108mm throttle body is working out very well. As for power gains or data logs, no I don't have those. Sadly, I can't find traction in this 40-50 degree weather with just my 555G2 tires. I really need ET Streets for this car. I'll buy those tires next once these are trashed. Trying to get my foot down in third to log a 3-4 pull isn't working out. I find my rear-end walking out a little at 80+ mph, which is spicy. lol.

What a fun car.
 

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The ET Streets are good - especially when new. I got roughly 6,000 miles out of the set I had. Considering the r888r's next to see how they compare.

I'm back on the Conti Extreme Contact Sports for now and have no traction either regardless of speed. I'm already ready for summer to be here!
 

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Yeah, the Kong 2650 may be the direction I take down the road. Will be interesting to see how the stock and ZL1 intercooler bricks perform with this thing. The 2650 Magnuson made for their LT4 application has intercooler bricks 10X the size of our stuff. That's got me skeptical for sure. On stock cube applications where the blower RPM will be lower, it may work fine, but who knows. We will be seeing these on the dyno soon and in the spring out at the tracks.

Hands down, cool blower though.
Large and efficient Intercoolers are definitely desirable.

But both E85 and Meth are oxygenated fuels.

Oxygenated fuel works well with supercharged environments.

-note- E85 as well as Meth have a very high ‘latent heat of
evaporation’.

This means that when E85 or Meth is used as fuel, it goes
through a change from liquid to gas and during this process it
absorbs heat from the intake charge.

A colder intake charge is denser and 'Greatly' improves power.

------------------------------------------------------------------------------

So, E85 helps cool cylinder temps.

And spraying Meth into the inlet side of the blower, as well as into the
blower manifold after the blower and intercooler, can greatly help
cool the mass flow within the manifold.

The IAT's that RPM gave in their video, would be indicative that
the manifold temps were under control, as they were less than
were the ambient temps as I recall.

The above is not unusual as sometimes you can see water
beads form on the outside of a manifold that has been running
on meth.

The car will easily go high 8:80's in my opinion, based on the MPH
if they can get it to hook during the first 60 feet and keep the car
hooked on the 2 to 3rd gear shift.

I have seen cars (lighter cars) go ~150 mph and ET at ~8.86 to 8.88.
I have seen cars go 8.75 @ about 152 to 154 MPH.

Albeit, all of the above cars were much lighter than the CTS-V
as run by RPM, and had much better suspension that could
be adjusted to set the tire on the launch.

All of the above cars were also run at NHRA National Events
where you also have the best track prep.

So with an MPH of 152.59, the car is fully capable of putting down
an 8.80 run in my opinion, assuming the air density is correct, but the track is not too cold.

Cheers
 

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Discussion Starter #300
Quick walk-around of the V.....enjoy.

Soon to come - Carbon Fiber intake tube (4.5" ID).

Also, still working on the LSA snout project. Final revisions are underway and I should have the finished casted prototype in late December. This should be available around Feb. Excited to see what a properly fed 1.9L rotor pack can do on this 427. I plan on hitting the dyno to do a before and after comparison. Both with the 108mm TB.
 
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