Crawford Billet Power Blocks

[nelsmar]

Originally Posted by Gords_zenith

I haven't read the whole thread so forgive me if this has been said already.

I have to disagree with this statement. Here are my reasons. 1) If you increase the runner length, then that will improve volumetric efficiency due to an increase in velocity of the air stream at lower revs. NA engines usually have VE of 80-90%, so long runners could improve it to maybe 85-95% depending on engine. My guess our car is closer to the high end of the VE range due to 4 valves/cylinder and advanced flow dynamics from using advanced computer designing. Remember - Short runners improve volumetric efficiency at high rpms and long runners at lower revs, which is why you see that the peak hp is 500 rpms sooner with the long runners. This is evident with some makes i.e Mazda RX8 original design, and the old Mazda 787B rotary that had intake runner "stages" to go from long to short as the rpms climbed.

2) why would tuning be required? They're not changing anything about the air/fuel ratio. The maf/map are still calculating the amount of air entering the engine.

If I'm wrong on this feel free to correct me. The rest of the thread with all the e85 stuff is out of my knowledge range...:-)

Unfortunately he cannot debate any more as he was banned.

The discussion is in this thread if you would like more info:
http://www.ft86club.com/forums/showthread.php?t=60608

[wootwoot]

Originally Posted by nelsmar

BTW that was 100% serious. I am ordering a set today. Lets find out how well they work! I'll try and get a car in for baseline this weekend.

Your the mother f$&@ing man....

[King Tut]

Can the mods delete or merge the posts in this thread into the other identically named thread?

[King Tut]

Originally Posted by wootwoot

Your the mother f$&@ing man....

Don't give him an even bigger head.

[Superhatch]

Originally Posted by P@ul

So, 19 HP with their tune... =/

Sent from my Nexus 5 using Tapatalk

From their website:

an increase of 19 Horse Power, 15 Pound Feet of Torque and narrowed up the torque dip by 300RPM on a totally stock BRZ

If this is stackable with other bolt ons and a tune this would be awesome news for the NA community. Also, expect this same product on Ebay for $100 by the end of next week.

[Pixie_Niner]

I've placed my order

[mike the snake]

So do these blocks replace the tumble generators, or do they go on top of those and raise the manifold?

[OrbitalEllipses]

Originally Posted by mike the snake

So do these blocks replace the tumble generators, or do they go on top of those and raise the manifold?

To the best of knowledge there aren't TGVs in our intake manifolds a la turbo Subies.

[sw20kosh]

This has been done a lot on rotary engines. You alter the shape of the torque curve by adjusting the length of the intake runners. They actually chop off sections of their intake runners to shorten them to extend the torque curve further to the right.

What crawford has done is altered the torque curve (notice the HP peak shift to the left and look at where torque starts to fall off up top) and if it truly is a stock ECU tune... the ECU/engine loves the heck out of this new intake runner length. You get a much sharper/drastic high rpm fall off of torque from this peak though (fall off of torque is now at ~6400 vs the stock ~6700 rpm.

The basic principle:





Has any OEM played with variable intake runner length technology?

[wparsons]

Originally Posted by sw20kosh

This has been done a lot on rotary engines. You alter the shape of the torque curve by adjusting the length of the intake runners. They actually chop off sections of their intake runners to shorten them to get more power up high I think.

This is what confuses me about these blocks. Any other engine a longer runner gives better low end power, and shorter runners give better top end power.

These show gains up top by increasing runner length. FA20 > physics?

[nelsmar]

Originally Posted by King Tut

Can the mods delete or merge the posts in this thread into the other identically named thread?

<3


Staff at Crawford just called me, ordered a set. I'll likely have them on a stock FRS next week.

[DJCarbine]

Originally Posted by sw20kosh

Has any OEM played with variable intake runner length technology?

Yes, but its usually just switching from short/long runners and not continuously variable

[nelsmar]

Originally Posted by wparsons

This is what confuses me about these blocks. Any other engine a longer runner gives better low end power, and shorter runners give better top end power.

These show gains up top by increasing runner length. FA20 > physics?

If you look at the graph you will see the same shape as the chart above... the power band is shifted left and up. Im starting to believe they may actually function. After talking to crawford about this and how forward they were with me when i doubted them... I am actually now quite curious how much gain can be made with this. I have been able to make decent gains ay 6800+ if i could shift that a few hundred RPM to the left... and up? That could be quite desirable.

Let me put it this way... Crawford offered for me to drive down and use their dyno just for R&D testing. If they want to back their product up that bad I am extremely interested.

Ill be doing these dynos:
Stock vs Tuned
Stock + Blocks vs Stock
Stock + Blocks vs Tuned + Blocks

[nelsmar]

Originally Posted by sw20kosh

Has any OEM played with variable intake runner length technology?

Yamaha R1 comes to mind.