transaman98

iTrader: (16)

Well I have been tossing around the idea of putting a sheet metal intake on a 427 with TFS 235 heads and from what I read the Fast manifold's or any other composite manifold for that matter really leave a lot of power on the table. Running a beck sheet metal piece would be nice but don't they run like 3k+? TPIS sells their sheet metal manifold for $2400 and it will fit under the stock hood which is a big deal for me. Anyone use this piece? Dyno #'s would be nice. Thanks in advance.

Here's a link: http://tpis.com/index.php?module=cat...t+Metal+Intake

transaman98

iTrader: (16)

sorry I meant to post this on the external engine not the internal. Feel free to move it.

71CamaroLS1

I have no experience with the TPIS, but you have to understand that, for the most part, there is no free lunch in intake design. The plastic intakes all share a common characteristic - relatively long effective runner length - which provides strong finite amplitude wave tuning in the midrange. In other words, they make lots of torque in the 4000 - 6000 RPM range, but they then begin to work against you as the revs go higher than that, reducing horsepower at peak RPM. For a street car, or even a street/strip combo, those characteristics tend to produce both better E.T. and better seat of the pants feel.

Now, if you're building an all-out race car, or an extreme street car, with 7500-8000 RPM redline and solid roller cam, you need a shorter runner intake to move the intake resonance tuning point higher in the RPM curve. That's where the sheet metal intakes come in. So you need to know what your desired outcome is, and make sure that if you're shelling out big bucks for an intake that reduces power through most of the streetable RPM range in exchange for bigger peak numbers, that is what you really want.

Stang's Bane

iTrader: (22)

Yes x2, this is correct and any other thing I can think of to say listen to this man here.

transaman98

iTrader: (16)

Good info to have. I know there is always a trade off to performance. If you want high rpm horsepower it usually comes at the sacrifice of at least some power down lower in the rpm's. Will a sheet metal manifold (obviously depending on runner length) not be advisable to use on a car that is used on the street? I'm not going to be throwing some radical *** cam in this thing and not be able to drive it around because of all the bucking, and surging associated with something that big. I want in the upper 500's hp with a 427 N/A through a TH400 and 9" 3.73's. Yeah its a tall order but that is why I am looking into sheet metal intakes.

Fbodyjunkie06

iTrader: (10)

You can make that power with a Fast ported 92/92 from Vengeance. I think they take them out to 96mm.

71CamaroLS1

taman98, IMHO you'll have to adjust your goals a bit. A TH400 with a loose converter, through a 9 inch, is going to exhibit close to 25% driveline loss (for reference, an M6 vette is closer to 10% than the "rule of thumb" 15% normally quoted for manual trannies). So to get high 500 RWHP, you'll need something like 725 to 750 at the crank. There's no way to get that from a NA 427 without resorting to a very big cam, and yes, a single plane or sheet metal intake. Your powerband range would have to be something like 5500-7800, and your converter would have to stall near that to take advantage of that powerband. A combination like that falls outside the parameters of what 99% of us would consider regular transportation.

Now if you're looking for a more strip-oriented car that can also handle an occasional cruise or trip to the local 7 Eleven, go for it!

I suppose I also ought to say there is an intake design which is good at taming very big cams - the Individual Throttle Body intake design, like this Harrop:

http://www.harrop.com.au/root_folder...fd7022-00.html

But there are lots of issues with cost, installation, and tuning - do a search on ITB or Harrop to get a feel for that.

transaman98

iTrader: (16)

The car gets maybe a thousand miles put on it a year. Its just an expensive sunday toy. I really dont wanna put a huge cam in the vehicle and have to put up with all of that. So what would a reasonable number to expect out of a 427, TFS 235 heads, and reasonable sized cam get me? Also what If I went with a 4L60E thats built to handle some high horsepower? I have a yank ss4000 laying around that I could use.

KCFormula

iTrader: (4)

If you want that kind of HP with good drivability you need to go forced induction. Good luck trying to make a 4L60E handle that kind of wheel power in a heavy car. A stout built TH350 or TH400 will handle those HP levels but just realize they are what they are, less efficient with a big converter.
If you need a perfect mannered car you are better off building a smaller motor and using the money saved on a turbo or supercharger kit.

transaman98

iTrader: (16)

4L80E? I'm trying not to be in denial about this one, but I am trying to see out my options.

KCFormula

iTrader: (4)

Having a '98 I'm not sure your PCM will accept the 4L80E tables. Aside from that you can use it but there are certain downfalls compared to a TH400.
If you want a bad *** street car that makes gobs of HP throw a single turbo or a F1 procharger on it with a forged bottom end and let the boost do the work. No need to run a rowdy cam, no need to screw around with high $$ small parts when you can just turn up the boost.

BTW Where in overland park do you live? My buddy lives there and has a dark blue TA WS6 w/ Fikse wheels and a nice H/C motor.

transaman98

iTrader: (16)

127th and quivira. I have a 99 harness and pcm chillin in the garage just waiting to go on.