KA intake manifold question - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

shayrgob240 · 11-11-2006, 12:46 AM

do all KA24de intake manifolds have the butterfly vavles at the end of the runners? or is that only in the 91-94 models?

IngS14 · 11-11-2006, 12:53 AM

only the FWD ka24de motor has butterfly valves on the runners,not on the 89-98 240sx ka24de motor.

Jung918 · 11-11-2006, 01:20 AM

91-94 240sx does have the butterfly for emission purposes.

http://www.240sx.org/faq/index.html

projectRDM · 11-11-2006, 07:51 AM

All 91-mid93 RWD KAs have the SCVs, but it's not for emissions, it's to counter the loss of lower end power with the more aggressive 240/248 cams. When the cams went to 232/232 they deleted the SCVs since the power curve was more flat with the milder cams. Basically if you have SCVs, you have the better cams. 89-90 SOHC KAs use them too, same purpose.

shayrgob240 · 11-11-2006, 05:32 PM

Quote:

Originally Posted by R240NA

All 91-mid93 RWD KAs have the SCVs, but it's not for emissions, it's to counter the loss of lower end power with the more aggressive 240/248 cams. When the cams went to 232/232 they deleted the SCVs since the power curve was more flat with the milder cams. Basically if you have SCVs, you have the better cams. 89-90 SOHC KAs use them too, same purpose.

so can I take them out? The reason why I'm asking is b/c I'm putting that motor in my 95 OBD II and I would rather keep everything the way it was before throwing in the rebuilt motor.

thanks for the good info

projectRDM · 11-11-2006, 05:37 PM

Pull them. Read up in here about the removal technique, I've discussed it before.

undesiredshoe · 11-11-2006, 05:44 PM

Quote:

Originally Posted by R240NA

All 91-mid93 RWD KAs have the SCVs, but it's not for emissions, it's to counter the loss of lower end power with the more aggressive 240/248 cams. When the cams went to 232/232 they deleted the SCVs since the power curve was more flat with the milder cams. Basically if you have SCVs, you have the better cams. 89-90 SOHC KAs use them too, same purpose.

trust this guy, he knows almost everything there is to know about 240s

11-11-2006, 12:46 AM	#1
shayrgob240 Zilvia Junkie Join Date: Jul 2003 Location: gurnee, IL Age: 40 Posts: 441 Trader Rating: (0) Feedback Score: 0 reviews	KA intake manifold question do all KA24de intake manifolds have the butterfly vavles at the end of the runners? or is that only in the 91-94 models?

11-11-2006, 12:53 AM	#2
IngS14 Zilvia Addict Join Date: Jul 2004 Location: DriftHeaven,CA Age: 45 Posts: 647 Trader Rating: (7) Feedback Score: 7 reviews	only the FWD ka24de motor has butterfly valves on the runners,not on the 89-98 240sx ka24de motor. __________________

11-11-2006, 01:20 AM	#3
Jung918 Post Whore! Join Date: Oct 2003 Location: CA Posts: 3,203 Trader Rating: (2) Feedback Score: 2 reviews	91-94 240sx does have the butterfly for emission purposes. http://www.240sx.org/faq/index.html __________________ Sale: Hello Kitty Horn Button S14 Rear Valences K.Y. Gordon the Thief (Tony Chen)

11-11-2006, 07:51 AM	#4
projectRDM Post Whore! Join Date: Dec 2002 Location: Atlanta Age: 51 Posts: 13,812 Trader Rating: (12) Feedback Score: 12 reviews	All 91-mid93 RWD KAs have the SCVs, but it's not for emissions, it's to counter the loss of lower end power with the more aggressive 240/248 cams. When the cams went to 232/232 they deleted the SCVs since the power curve was more flat with the milder cams. Basically if you have SCVs, you have the better cams. 89-90 SOHC KAs use them too, same purpose.

11-11-2006, 05:37 PM	#6
projectRDM Post Whore! Join Date: Dec 2002 Location: Atlanta Age: 51 Posts: 13,812 Trader Rating: (12) Feedback Score: 12 reviews	Pull them. Read up in here about the removal technique, I've discussed it before.