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if i bought a r/t intake manifold without the secodary butterflies and put it on my 05 sxt would i lose horsepower???

not a necessary LOSS, but between 3k and 5k there would be a slight bog - someone did a dyno with the butterflies open all the time, and ones with it set at stock, and the result was nil, but it did show that with it closed between 3k-5k it performs better. SO, if you do not mind a slight bog in that range, it will not make much of a difference.

I hope that you have a header or port job in the sometime soon time frame(i thought the exhaust side was the bottle neck for you guys..). I would almost just get a stock neon's plastic intake from a junkyard and make the "ghettoblaster". Also remember that the intake on the magnum has a different angle then the stock neon, so if you have a cai or anything you might have a problem witht hat fitting..

^^^trudat...

Also, it is the exhaust side that's the bottleneck... the magnum intake is however a great first mod for a non-mag motor... but upgrading to the mag head will net most results. And do not forget the mag exhaust mani, that is good too. Do not bother P&P the head on a stock neon 2.0L, even the best and most expensive P&P (which runs more than a mag head) will not flow as well as the mag does (so I have been told).

I would think if they are closed it would make more torque since it's a longer runner than the stock plastic manifolds.

Until he has his electronics working wouldn't it make sense to close the secondaries for better low to mid range torque improvement?

own3d5974 wrote:if i bought a r/t intake manifold without the secodary butterflies and put it on my 05 sxt would i lose horsepower???

There, for clarification

I have a picture of the stock neon head and the magnum head. there is no way that you can port the stock head enough to match even the stock magnum....here it is:

Knoxville_R/T wrote:I have a picture of the stock neon head and the magnum head. there is no way that you can port the stock head enough to match even the stock magnum....here it is:

WOW...thats quite a difference, never knew it was that much...

yeah, what is it total, a 1/2" or something diameter difference? 3/8"? I cannot remember, I saw a post somewhere else with the messurements of each port.

Knoxville_R/T wrote:I have a picture of the stock neon head and the magnum head. there is no way that you can port the stock head enough to match even the stock magnum....here it is:

Wow.

Standard exhaust ports are 1.1875" and magnum are 1.3570"

Thats a 30% increase in cross-section area (1.108in^2 and 1.446in^2 respectivly)

That picture looks a bit exaggerated to me for some reason ...almost like that mag head has been ported already. Maybe it's just me. Here is one of my pictures of stock vs stock that I took when I swapped my heads...




Important note...the standard head has exhaust stains on the outside of the ports making them appear bigger...I would say the stain is about 1/16" around the entire edge of each port. The mag head was completely clean on the flange surface....

well thanks for the info guys......the reason i ask is because it seems like a lot of money and a pain to get the secondaries to open on a non mag car. so i see alot of people sell the mag intake manifolds with no butterflies for cheap. i was also looking at the indy manifold but i like the stock r/t look better

DO NOT BUY THE INDY. Not because it is not a good manifold, but because it flows TOO GOOD for a car with out a turbo or all the bolt ons.

I did not think it was that hard, just a window switch and some wiring. Search i know someone did a write up on it.(or at least posted pictures)

nofrills05 wrote:

Knoxville_R/T wrote:I have a picture of the stock neon head and the magnum head. there is no way that you can port the stock head enough to match even the stock magnum....here it is:

WOW...thats quite a difference, never knew it was that much...

it might not be able to port to the size of the magnum head but i bet it can get pretty close ...theres alot of extra metal on the non magnum head... i dont wanna throw any sizes out cus ill be yelled at for in-accurracy..lol... but the non mag head gets way bigger when ported....

Yes, there's lots of extra there, but there are also huge humps in the exhaust bowls and you get rid of them completely because it's not solid, there water passages under it to some extent.

yea i thin im going to swap my head for a r/t and use there stock intake manifold and some type of header.........there is a r/t head on ebay that i was looking at its $300 and pulled of a 04 with 29,xxx miles.......one other question is if i do swap the head would it run right if i do not use the r/t pcm

I would think it would run fine, just like you did a huge port on your stock head.