i have added the ability to update your existing manifolds to the new version. it is an option inside the respective intake manifold product page on our website. so if you want to update tweaked manifolds, check out the tweaked manifold page on our site. if you want to update the sheet metal mani's, check out that page.

 

Nice procuts both the stock and the custom tweeked manis!!! Very nice!!

Another benefits:

Much better idle!! (one big plenum).
In additon it eliminates the restriction of the y-pipe before the manifolds imo.

Pressure drop: 1.5 psi just with the bypass after tweeking my stock manifolds in a similar way . (total pressure drop 3 psi!)

Maximum boost pressure 1.2 bar / 17.5 psi @ 6100 stacked 166/65 (it equals aprx a 190mm crankshaft pulley).

Steven

Berlin Germany

 

Yes they cause the butt-o-meter to kick upwards a good bit. It is suprising that this has not been considered and or used before. Designing the CROSS-OVER intake was a follow on to my DCAI thinking which Rob was kind enough to finish out an run with it and made it look good. I may consider getting a set to clean up my car one day and replace the originals.

I have another design change working and will try to get it posted in the first quarter of 2018. Should be helpful, more to follow.

FALL COLORS, enjoy the holiday WDY

https://www.crossfireforum.org/g/picture/4812319

https://www.crossfireforum.org/g/album/4812318

 

will this mod require more fuel? I'm about at the max for my setup...

 

With the lower boost indicated pressure your fuel to air will be GREATER as the pressure differential across the fuel pintel will flow MORE. Higher boost has the effect of retarding the fuel from the injector due to the LOWER fuel pressure DIFFERENTIAL. Enjoy, Woody

 

English please woody lol.

 

Lower boost more fuel. Boost tries to push gas back into the injector - reducing flow and thus fuel delivered. WW

 

cool! so would I need to retune, or would the ecm auto adapt? Also, how much difference tq and whp would there be since I already have the tweaked manis? thanks very much in advance!!

 

..........

 

anybody have this info?

 

I do think you will get more air through the engine, when the supercharger doesen’t run. Here less restriction works.

I don’t think you will get more air through the engine when the supercharger runs. The twin screw supercharger always makes the same air volume at equal rev. There is (almost) no loss of volume because of the bottleneck in stock you can dig. But of course air temperature keeps lower, lower load stress - it is always fine.

AFR – I think is minimal affected.

Nonetheless dyno experience would be helpful to approve/disapprove.

 

Enjoying the more aggressive low end power! The Conti Extremes are useless in all situations now...lol. Loss of traction into third while modulating throttle. Depressing pedal continuously results in 65mph tire smoking fun or the increasingly annoying traction control power drop. More often than before. Acceleration is extremely smooth while covering some acreage quite quickly when tires let me.

I reinstalled NW's downpipes soon after Crossovers and I feel they work well together. Better all around power and an amazing new deeper tone. I was told it sounds "extremely naughty" after a 1st & 2nd gear traction loss display. Supercharger screams now! Intoxicating notes from both ends. ;-)
My driveway is 375ft. long. I let off half way. It was an effortless, moderate pedal 3td gear show.

Thanks Waldig & Rob!!!

 

Iam glad to see that the manifolds are being received so well and proud that Rob took my design and cleaned it up so nicely.

How nicely, well since I made the first originals, I was happy, until I saw the ones Rob was offering. THen I decided that I needed to upgrade to Robs cause they were so organized and functional. The originals worked but were homely looking.

Well TAAAAAA DAAAAA I finally have a set to install sitting in the garage. Id do the install except I retired and have been working on old ham radio equipment while its been COLD and windy. When we get the weather to improve, they are project next to install.

The ease of installation alone will be a great improvement over mine and i cant wait to see if the super charger sound is improved even more. As I get them on Ill do a photo shoot for the gallery so you all can follow along.

WEEEEEE Enjoy, WDY

 

I must ad that I upgraded from "tweaked" SRT manifolds to Crossover NW's sheet metal manifolds. So, the whine [read wildcat howl] was the first thing I noticed and I can't compare to NW's non-crossover phonics.

Either way, tapping the throttle just the slightest bit releases a neat pitch akin to a cat. An angry big toothed cat...lol. Too cool.

 

I don’t understand the gains on low rpms – has anybody a theory?

Fascinated by the drop of pressure level, I read some papers and tried to understand the physics behind the phenomenon. So in the meantime I think I understand the performance gain on the top end: PICTURE

You can see an operating line depending on the sc-map and the assosiated engine suction lines.

In stock you have a more then 3 psi (0.2 bar) higher pressure then nessessary because of the Y construction – no pressure equalisation and way to small dimensioned (15 cm² - one feed). With the crossovers you always feed from 2 sides steadily (50 cm²). (… so the dynamic pressure drops the same as the operating pressure.)

The 3 psi pressure drop on max rpm on a stock car gives you 10 kW (… less supercharger loss) and additionally maybe 1% more volume flow. The pressure drop on lower rpms is far less – because the pressure drop depends mathematically on the square of the volume flow.

Look on the map – 10 kW gain on max rpm; less then 5 kW at 5000 rpm – you can’t find appreciable gains below according the sc map.

So back to my question – many of you tell about the gain on low rpms. How does that work together - the facts: With the crossover you feed far more constant. When with stock imf an inlet valve opens you have a higher initial pressure which drops fast (change from 1 to 2 feed) – maybe you have in stock version more oscillating air that matters – most properly you loose some fresh air to the exhaust? What do you think?

 

You can see an operating line depending on the sc-map and the assosiated engine suction lines.

In stock you have a more then 3 psi (0.2 bar) higher pressure then nessessary because of the Y construction – no pressure equalisation and way to small dimensioned (15 cm² - one feed). With the crossovers you always feed from 2 sides steadily (50 cm²). (… so the dynamic pressure drops the same as the operating pressure.)

The 3 psi pressure drop on max rpm on a stock car gives you 10 kW (… less supercharger loss) and additionally maybe 1% more volume flow. The pressure drop on lower rpms is far less – because the pressure drop depends mathematically on the square of the volume flow.

Look on the map – 10 kW gain on max rpm; less then 5 kW at 5000 rpm – you can’t find appreciable gains below according the sc map.

So back to my question – many of you tell about the gain on low rpms. How does that work together - the facts: With the crossover you feed far more constant. When with stock imf an inlet valve opens you have a higher initial pressure which drops fast (change from 1 to 2 feed) – maybe you have in stock version more oscillating air that matters – most properly you loose some fresh air to the exhaust? What do you think?

 

Your pressure drop is because your are taking more air from the SC which means it output pressure falls. Think of a leak, lower pressure because your bleeding off more air.

Your bleeding off the pressure because the pair of manifolds flow more air into the cylinder as they share the air flow - less restriction from the SC to the intake valve. More air better volumetric efficiency and thus more power. It took me a while to figure this out when I first made them, I thought there was a problem. I even plugged up the crossover to see that the pressure went back up to previous readings.

When my experiments on the use of a second intake ((DCAI)) were going on, the bottom end power gain was wild, like 25 hp on the dyno charts. THat was simple as the intake to the TB on the SC was breathing rarefied - thinner air due to the friction losses in the intake and filter. I actually did some blasts to measure the pressure loss with the single cold air intake and it WAS 1 PSIG!!!! Thats enormous because we carbon based units are breathing 14.7 PSIG air and a single PSIG loss is like 7% !!!!!!!

The buttometer showed good gains from the DCAI and the crossover manifolds that robs making are allow you to have the best intake that can be imagined. Unless you add the bigger down pipes, there is almost nothing left to improve. Were not getting a different SC or engine, but with the response and power these add ons provide, there is no need to go crazy looking for more power. THis engine breathes very well now!

Enjoy, Woody

 

*THis engine breathes very well now! Enjoy, Woody*

I'll say!! Now I gotta hook up AFR monitoring device as well as boost gauge to see where my power goes into 3rd up high.

Just might be spinning tires, but it's good to know.

Zoom!

 

Hi Woody,
with the air intake I go with you – if you have less then atmospheric pressure infront of the sc, you lose air mass flow in this percentage.
Behind the sc the things are not so easy. You should lose far less with a restriction. One sc rev is a nearly constant amount of air. The rev ratio sc vs. crankshaft is constant. You lose pressure if you eliminate the restriction but shouldn’t gain much air mass flow. If you had a turbo the things were different – the turbo revs just faster, you would gain much air mass. The gain on the low end must be something else.
According AFR – I think this should not be an issue with stock tune if the car is unpullied.

 

Air is compressable, makes all the difference. Air flow is not constant per revolution, there is cavitation and compressability to deal with. Pneumatics are rather complex. WW