butterfly removal

[KEMP]

i searched and searched, but i cant find the write up or the thread where they delete the butterflies

ive seen it before but cant seem to find it again, and wanna get rid of them

does anyone have the link handy?

thanks

[r34 gtr]

Boo BAM!!

zerothread?id=257757

[KEMP]

awesome, thanks man

[D_Stirls]

Just wondering why you want to remove them? they are worth a heap of torque in the bottom end (and I mean like 50% more torque when they are working).A few weeks ago I have my car on the dyno and got some evidence, have a look.http://www.nissansilvia.com/fo...65186

[21FOX21]

I wonder what the difference is with them out. Less turbulance should be more power up top atleast.

[r34 gtr]

Thing is, they are in there. That is, there is STUFF in the way of air trying to get into the cylinders. Sure it may not be a huge obstruction when they are open, but it is an obstruction nonetheless. I didn't like the idea. All the Subaru guys ditch their TGVs, and while the CA18 butterflies open to 100% as opposed to only 65% or so for the EJ205, the principle is the same.

I just thought the fewer things in the way, the better. It also makes the engine much much simpler. I only have two vacuum lines!

[Fleemer]

in a positive pressure setup the turbulence would be minimal. And would only effect top end power (if you where for example trying to get power out of the 9k range)

Just my 2 cents.

(actually would create just as much turbulence with them out unless you fill in the groves where they used to be.

[boost_boy]

I always say to thee, do you your own thing. Get them to function right and you should see the difference as opposed to them just being stuck open. This is an 1809cc engine and I don't know what type of torque you guys are looking for on the low end. But if you really want some effective low end torque, you guys have "FAILED" when you chose the CA18DET. Either you want the CA18DET because it's cheap, rev-happy, mother of the RB series engines, or just looks cool. But to be wishing upon butterfly valve trickery for big torque on the low end is an understatement. This engine shines past 3500rpm, not below it .

Dee

[sjbsuperman1425]

i agree with you Dee.. but really, when you think about it, whether you are building the CA for street or drift, you are rarely in the low end of the spectrum..thats how my friends and i look at things.

[boost_boy]

i agree with you Dee.. but really, when you think about it, whether you are building the CA for street or drift, you are rarely in the low end of the spectrum..thats how my friends and i look at things.

I'm glad you do, but some won't and they are entitled to their opinions/experiences. The CA wasn't designed to be torquey cruiser engine, so let us not kid ourselves because size truly matters when it comes to torque. So it's okay to waste time playing with your butterfly toys, but if you guys really want to feel what this engine is about, tune it right and you'll then understand why butterfly valves are for girls . I have a 1991 B13 sentra at my house that has a stock CA18DET with a GT35R dual ballbearing turbocharger, custom manifold, hks wastegate, standalone engine management, 1000cc injectors, and only a street tune from me and I tell you, once a person drive a car like this one, butterfly valves will be a thing of your past. I won't steer you wrong guys; been at this too long to know the difference. But whatever you guys decide, drive hard and don't regret your decisions.

Dee

[sjbsuperman1425]

i think i might remove them when i take out the butterflies when i do the KA TB swap. just to make it more simple. but who knows, i may get lazy

[boost_boy]

i think i might remove them when i take out the butterflies when i do the KA TB swap. just to make it more simple. but who knows, i may get lazy

I'm lazy! On one of my engines, I left 'em in, but they get no vacuum signal and the engine doesn't miss their functionality, either. On my built engine, they are removed, shaft holes welded, and ports are matched to the head. So whatever you decided, it should work either way.

Dee

[dash]

1st gen toyota 4AGE has a similar butterfly system = TVIS. Most blindly delete them when going turbo also. First corolla guy I've seen actually experiment with his butterfly opening, using a small IHI turbo on his megasquirted 4AGE said, the V8-like torque almost felt unnatural coming from such a tiny gutless 1.6L It certainly adds another dimension to the daily driving experience.... IF... response & torque is the priority. Everything is a tradeoff.I'm definitely gonna try the same with the 8 port CA18 in the corolla

[float_6969]

IDK who is moderating this forum, but that info should be in the stickies. Somebody is slacking!

Sorry guys/gal it's in there now.

[r34 gtr]

Not to mention I should have a totally sweet custom title for that write up, but that can wait until I do my "how to rebuild the bottom end of your engine" writeup I've apparently been suckered into writing over my spring break.

[float_6969]

The only custom title you're getting is going to read, "Resident Shade Tree School Teacher"

[r34 gtr]

^ Can I have that one? That sounds fantastic.

Boy if you ain't workin' on yer car on some cardboard out in the front yard, get the hell out! I don't own jack stands, but I have a pile of cinder blocks.... Is that my tooth or yours?

[Logan76]

^ Can I have that one? That sounds fantastic.

Boy if you ain't workin' on yer car on some cardboard out in the front yard, get the hell out! I don't own jack stands, but I have a pile of cinder blocks.... Is that my tooth or yours?

Sounds like how most things are done here in western pa, lol.