Who would be interested in a sheet metal intake manifold for the 4.9 Caddy engine? I am working on two designs. One based on the GM TPI system and the other based on the LSx system. I do not like the Allante system as it blocks access to the engine. You can't even add oil easily. I also plan other 4.9 specific performance mods, but those are for future revelation.

In case some of you are unsure what a sheet metal intake manifold is, below is a link to Self Racing Engines with an image of their manifold for the LSx series engines.

http://www.selfracing.com/intakes/intake10.htm

[This message has been edited by CopperBender (edited 10-22-2007).]

Sign me up!!!!!!!!!!!!!!!!!!!!...seriously...

...I would like to see what you come up with...

[This message has been edited by Mickey_Moose (edited 10-24-2007).]

It looks like sheet metal to me. The particular metal is aluminum, but it looks like sheet metal...

Building a sheel metal intake for the caddy motor is going to be difficult, its not like an ordinary intake, because the valve covers sit on top of the head and intake

Not to mention the pesky pushrod holes that run right along side the intake ports.

Best bet would probably be to mill the runners out of a production manifold and weld sheet metal runners in their place. Not sure if you could keep the production injector bosses and fuel rails or not... probably depends on how radical a change you want.

Have any of the people proposing sheet metal or custom manifolds for the 4.9 ever flowed the heads or messed with the ports? I hate to break it to you, but those heads are junk... I think they're one of the biggest reasons that getting power out of a 4.9 is like getting blood from a stone.

[This message has been edited by Will (edited 10-23-2007).]

I've fully considered the difficulties with building a sheet metal intake for the 4.9. Yes, the unique way the manifold is designed poses a few problems, but nothing that can't be overcome. I've worked with sheet metal (copper, brass, steet, aluminum, and stainless) for several years as a metal sculptor. ANY metal that is measured in gauge thickness (3 to 38 - higher number = thinner thickness). Any metal whose thickness is greater than 0.2391 (3 Guage) is considered PLATE metal.

The Self Racing manifolds are made of a combination of machined plate and formed sheet aluminum.

I know that there are some flow issues with the 4.9 heads, however, a well designed intake can go a long way in correcting some of those problems.

My design incorporates replaceable runners of different lengths. This will allow the owner to tune for low to mid-range torque or for high RPM horsepower. Not really sure how long the 4.9 will live at high RPM.

One of the main reasons I embarked on this project is that I don't like doing the same thing as everyone else. Why else would I have a Fiero with a 4.9 Caddy engine waiting to drop in? I know that when I open the engine compartment, I'll never hear, "My uncle Bob has one just like that."

I've had a little experience at something like this before. In 1989, I designed and built an electronic fuel-injection system that incorporated a two-piece sheet aluminum manifold for my 1972 Harley Superglide. It worked (and still works) great. I gave the bike to my oldest son and he still rides it. Had 200,000 miles on it at the time. In the years since he has put a lot of miles on the bike and the FI system has never failed.

Thanks to everyone for the interest. I will keep all posted on the progress of the project.

I worked on a few sheet metal intake designs for the 4.9 but eventually settled on making an upper intake for the Allante lower. I haven't fabricated it yet but the design is simple. Open phlenum above the runners with a TPI throttle body on the side facing the rear of the car ( to work with my expected turbocharging setup).

Good luck though. I'd be interested to see what you come up with.

[This message has been edited by vafierro (edited 10-23-2007).]

quote Originally posted by CopperBender: I know that there are some flow issues with the 4.9 heads, however, a well designed intake can go a long way in correcting some of those problems.

Just as long as you know you might not get results commensurate with your effort...

[This message has been edited by Will (edited 10-24-2007).]

I believe due to the heads it is not likely that significant HP increases can be seen in the 4.9 without forced induction. I've been looking at every 4.9 build out posted and even with extensive mods the effort doesn't seem to match the HP numbers. I know the car will respond to turbocharging (i.e. PBJ/Her86GT) so I'm going to add the Allante intake as well as a turbocharger. I'm now working on an upper intake for the Allante with an integrated water/air intercooler. Doing that is probably still less effort than what you are trying to do here but with a larger potential gain (intercooled turbo vs normally aspirated 4.9).

I do applaud your efforts, so don't take my comments the wrong way. I'm just looking for proven performance so I'm reproducing something I know works well from past examples.

Got pics of the Harley? Sounds interesting!

[QUOTE]Originally posted by vafierro:

I believe due to the heads it is not likely that significant HP increases can be seen in the 4.9 without forced induction.

Perhaps it's the heads and perhaps not. Someone needs to put that stock intake (especially the lower unit) on a flow-bench and see how much HP it will support.

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[IMG]



Trueleo.com/fiero.htm
RSpiderII@aol.com

quote Originally posted by vafierro: I believe due to the heads it is not likely that significant HP increases can be seen in the 4.9 without forced induction. I've been looking at every 4.9 build out posted and even with extensive mods the effort doesn't seem to match the HP numbers. I know the car will respond to turbocharging (i.e. PBJ/Her86GT) so I'm going to add the Allante intake as well as a turbocharger. I'm now working on an upper intake for the Allante with an integrated water/air intercooler. Doing that is probably still less effort than what you are trying to do here but with a larger potential gain (intercooled turbo vs normally aspirated 4.9). I do applaud your efforts, so don't take my comments the wrong way. I'm just looking for proven performance so I'm reproducing something I know works well from past examples.

Don't forget that PBJ's car only trapped 109ish... That's only about 280 at the wheels.

bump ..any new news??
I am soooooooooooooooooo interested in something more than this boring intake on my 4.9
My project is going great in this Florida weather..lol.(sorry guys) but looking at the other 4.9 builds we would love to get some serious hp levels with some high performance enhancement to our 4.9's
Santa will you please bring me say..... a beautiful,days of old,z-28 crossram looking intake that would mate right down on top of my 4.9 with the throttle of a cheetah and an exhaust roar of a lion...(can you tell I just read the "kiddies" a bedtime story..lol)

I've completed the design work on the first version of a complete manifold. It's a tunnel ram with changable top. You can mount single or double carbs, or vertical or horizontal TBI simply by changing the top. I've also come up with a completely new system. It's one of those "Why didn't I think of that before" type of ideas. I'm consulting with a patent attorney at this time. A friend of mine owns a CNC machine shop and is doing the prototypes for both items. As soon as he has them ready (and my attorney approves) I will post pics of them here.

As soon as pictures are up I will decide whether or not to get out my wallet =) Have any idea on a price ?

Great idea! I would certainly be interested.

Bump...to keep it out of the archives...

Is this thread dead?

quote Originally posted by CopperBender: I know that when I open the engine compartment, I'll never hear, "My uncle Bob has one just like that."

Actually, you might. Some random Joe walked up to the garage as I was working on my Formula one day and struck up a comversation about Fieros. He claimed all sorts of wild things. I just smiled and nodded. He said he'd had a Northstar Fiero done years ago. I showed him mine. He plainly had no idea what he was looking at.

Keep talking to your attorney and your cnc friend. We are axoius to see what you come up with. If it is anywhere near affordable, I think the demand will come. Price range around $250 - 500? You may find that you prototype something that could be cast later to save money. Anything to improve the ponies on these plentiful motors and more than the Fiero group will take notice.

[This message has been edited by Mark A. Klein (edited 12-12-2008).]

Obviously developing something that in-depth for the Fiero community is a waste of time. However, if a complete top-end package were available for this engine, it might be able to find a market. I'm sure there are lots of racing classes that would like to have a 350# 5 litre engine that could make 350-400 HP. These numbers would be quite attainable with aftermarket heads and intake developed together and dispensing with the factory head/intake interface altogether. Even if it were $2500, with compete engines available in the $500 range, the whole engine would still be fairly cheap by racing standards, especially considering the aluminum block and weight involved. An all-aluminum SBC is going to set you back $5-6K just for the block, heads & intake.

quote Originally posted by arte444: Is this thread dead?

Well, I don't know if this thread is dead, but its originator, CopperBender, last posted to it one year ago:

quote Originally posted by CopperBender: I've completed the design work on the first version of a complete manifold. It's a tunnel ram with changable top. You can mount single or double carbs, or vertical or horizontal TBI simply by changing the top. I've also come up with a completely new system. It's one of those "Why didn't I think of that before" type of ideas. I'm consulting with a patent attorney at this time. A friend of mine owns a CNC machine shop and is doing the prototypes for both items. As soon as he has them ready (and my attorney approves) I will post pics of them here.

Because that was posted by CopperBender on December 19, 2007, it appears that if there will be any further progress on his sheet metal intake idea for the 4.9L, it's evidently going to be very, very s-l-o-w.