Ok, on to the filler pieces.

 

another

 

Damn, forgot to attatch image.

 

another

 

another

 

phat ****, phat ****

 

are you going to smooth out the inside of the runner before you seal up the back?

 

This is leally cool.

 

Yep!

 

I think I will just clean up the center rib on the inside. Pictures
don't do it justice but this added alot of area to the runner.
I think this will accomplish what I set out to do. I wanted to turn
the runners into plemun area and even with cylinders 5 and 7
drawing together they will not be able to create enough velocity
in the siamesed runner to create any ram effect therefore the
siamesed runner is now plenum area.

I need to make the fillers for the other set and weld them up this
weekend. You should be able to get the aluminum rods and flux
at any radiator supply store. I bought mine at AutoKool, they are
a national chain and sell tanks, cores, presses and about anything
to do with radiators and condensers. The kit came with 8 rods and
a small can of flux for $15. The kit was enough to do the 4 outside
welds. I will need 2 more kits to do the rest.

 

Oh by the way, the filler pieces are from old core GM computers.
Just take some tin snips and cut what you need out of the tops.
1 top makes two fillers.

 

Swapmaster, You are a Stud.

No Im not Gay.

Your tempting me to hack Up my Stock Runners Now, We will have to see.

a bit of sanding, and a Coat of paint and those things will Look Factory fresh, Too.

I knew you were all right

 

Why not do the same on the outside & have true siamesed runners?

 

The reason I did It this way is to maintian structural integrity.
Cutting them the way I did and welding the center first fairly
assures me that they will not warp too bad. Minimal enough to
allow surfacing the flanges to true them back up.

I believe if you cut the outside open as well, you would need a jig
to hold the 3 flanges in place while you welded them back up.
Otherwise they would twist out of shape so bad they would never
bolt back on.

toga, toga, toga

 

You could do the outside first..weld, then cut the inside. But either way a jig wouldnt hurt.

 

Any one use this stuff?? 35 bucks for 22 rods shipped.

http://durafix.com/

Looks good, now to get a second set of runners...hehe

 

I don't see any benifit to doing the outside. With the inside joined
as they are, I think it will have more than enough airflow to feed
any small block engine, even the big cube ones. But then again
I couldn't say for sure.

 

I partially agree, you're adding a lot of volume there. But how much plenum is too much? An LT1 intake has a pretty hefty plenum size; bigger than TPI, and its runners are still shorter than the stock TPI base still... I don't think you can over-do the runner volume by doing the outsides as well. I'm sure someone will find out soon enough

Matthew

 

Well that's another debate all in itself.
Plenum V. Runner. The plenum is very critical to a carburated or
injector on throttle body setup because the suspended fuel
mixture needs to keep moving or the fuel will fall out of the air.

Too large a plenum and you need to turn some high rpm's to
keep the fuel suspended. Too small a plenum and you get good
suspension but loose your pool of mixture to draw from which
kills top end hp.

TPI motors get away from all those bad things by injecting fuel at
the valve. Therefore we don't care about plenum size much any
more. We are more interested in runner lenght and volume.
Our motors give up and fall flat at about 4500 rpm. This is due to
the runner lenght and volume. Long skinny runners designed to
create hight than normal pressures to develop at the back of the
intake valve after it closes so that when it opens again the
pressure sitting there waiting will help to fill the cylinder.

Problem. The runner is "TUNED" to give up at 4500 rpm or so.
This is a function of it's length. The intake as being designed for
a 305 was not intended to crank rpm's.

Now to get it into the upper rpm's we need to shorten the
runners. We can siamese the base and leave the runners alone
which seems to do very well or we can siamese the runners and
leave the base alone.

Plenum is plenum, don't matter how large it is on our TPI engines.
I did the short side radius because air likes to take the shortest
route. As they are now, they are plenum area because they will
by far outflow the head and can no longer help develop pressure
at the back of the intake valve.

So increasing the size of the plenum plays no significant role
for us or the forth or fifth or sixth or seventh gen owners.
(hey optimism never hurt anyone did it?)

Therefore I don't see any advantage of doing the outside also.

 

Ummm....will those things outflow SLP Semi Siameased runners. I might get them sometime next year...i am porting the hell out of the base like MadMax did...will adding the SLPs hurt? All that crap you were talkn about half confused me but 3/4 educated me.

 

Here camaro this may help explain. This is edited from a post I put
up a while back.

An engine is tuned to a desired rpm range by the intake manifold.
The TPI intake is tuned to peak at about 3500 rpm. It comes on
strong off idle and gives up after about 4500rpm.

The lenght and cross section area of the stock runners from the
plenum to the intake valve, including the head, are designed to
keep the mass of air in the runner moving toward the intake
valve at lower rpms. The way this is designed to work is that at
lower rpms, after the intake valve closes, the air in the runner will
continue to move toward the intake valve so that when the valve
opens again there is pressure at the intake valve from the still
moving air mass to help fill the cylinder.

What happens above about 4500 rpm is that the stock TPI setup
does not have enough air flow due to the small cross section
of the the long tube runners which is what keeps the air mass
moving toward the valve in the first place.

It is easier to look at it in reverse from the head side of things.
When the intake valve opens it allows air to enter the cylinder.
If there were no intake manifold at all, there would be no "ram"
effect from the runner to help fill the cylinder. The engine would
have to reach a certain rpm until shear vacuum from the piston
moving down the cylinder created a low enough pressure in the
2 inches or so of "runner" in the head to cause a high enough
pressure to develop at the back of the intake valve when the
valve closes. Only then will the engine begin to develop useable
power.

Now, for the intake manifold. A short runner has a small air mass
which does not fill a cylinder a lower rpms well but can be set into
motion easily at higher rpm's. We don't really need the ram effect
at high rpm's due to the velocity of air moving in a high cranking
engine.

A long runner has a larger air mass which can fill a cylinder very
well at lower rpm's due to it's ram effect but is not very effective
at higher rpm's.

Our intakes have a combined runner lenght of 13.5" a mini ram
has a runner of like 3.5", that's 10" shorter than ours. A standard
carburator style dual plane manifold has an average runner length
of about 7" and a single plane manifold has a runner of about 4".

When we siamese the runner tubes (each pair joined as one),
we effectivly turn them into plenum area because their air mass
is now too great and will move too slow to have any positive
effect on the back of the intake valve.

That leaves us with the runner volume of the base to play with
which in our case is just under 6.5". Siamesing the base will
shorten the runner even farther which will raise the rpm band
higher. The deeper you cut, the higher the power band.

 

i just talked to our welder here at work and he told me he can TIG weld a peice of alum. on the front and back side of these runners with no problem.turns out he has done alot of alum. welding in the service on air craft carriers.so all i have to do is find a place to get the alum.and cut the rest of the runners out.
we'll see what happens?

 

My problem was that nobody here was comfortable with welding
stuff this thin. I guess the shops around here don't do alot of
aluminum work.

I'll tell you what though, brazing with these aluminum rods is real
easy if you have the equipment. I was sealing up holes that I was
accidently burning in the runners with no problem.

 

well i have most of the first runner cut out i just need to get some cutting disks for my dremal,i used a wiz-wheel to do most of the work.i'll use the dremal to get to the rest.i'll post some pics after i get the runner fully cut.

swapmaster what do you plan on doing to your intake base?

 

The stock base is not as bad as you may think. I ran a micrometer
through the ports and it won't take much to hog them out.
The only real restriction is the area from the head to about 2"
up into the manifold.

I will start a new post when I do it but it will just get ported and
matched to the new runners. I may siamese it a couple of inches
but not sure right now.

 

nice work man!! lookin good

 

Ok, here is an attemp at brazing the first inner piece.

 

Another

 

I know it looks like crap but hey, as long as they seal up.
It will take some grinding and filing but they will look good.
I have a question. What do you guys use to grind with? I use a
dremel for the fine work and an air die grinder for the rough stuff.
I looked at a roto zip because it takes 1/4" shank bits but is it
the best to use or is there something else that will take 1/4"
shank bits that is easier to work with?

 

Hey bandit, are you going to have your guy try to weld them with
the spool gun. If he has not bought on yet, I have a line on one
from Lin-Weld that is a new floor model for like $500. I can hook
him up with it if he wants. It's like an $850 gun.

 

Looking good.... let me know when you have em done. They will look good once your done and Have them powdercoated.

 

Try a 90 degree angle diegrinder, they are light weight and easy to manuver. I also have a 4" extension for mine with a 1/4" collet on the end to get into the really tight places. I do a lot of aircraft sheetmetal work so I have access to a wide range of tools for metal working.


~M~

 

i don't really know but he's the welder and i'm the idea man

 

TTT..... swapmaster why dont you do the outside of the runners for a fully siamized runner.....

 

I don't see any reason to do the outside. As for being truly
siamesed, these are.

 

Here is a shot of the inside of the new runner.

 

so what's the hub bub.............bub?

 

I gave up. Going with an LT1 intake.

Anyone want to take over this project? All the pieces are cut and
fitted. Just needs welded together......

Serious inquiries, send me a PM.

 

Back in the 80's Guldstrand built the GS80 Corvettes and cut the TPI runners open and had them welded back with plates on the back and inside of the runners.This was before all the TPI stuff came out in the aftermarket.
Flowed pretty good for its day and on a modifed 350 with ported heads,cam,377 cubes,the motor made 370 HP and 420+ torque with a top speed of 175 MPH.
It pulled to 5500 rpms as well.Not too bad considering what they had to work with.No more 4500 rpm wall.

Good project but think it would easier to do this work with SLP runners and modifify them more so like some others have.
Nice job though.

 

We have a winner. Bandit will be taking over this project.

 

i took the set of runners that had the two peices that needed to be welded in to our welder at work.he had them done in about an hour and a half.and the only reason it took him that long was he would weld a few inches and let it cool down then do another few inches.i must say his welds are almost a thing of be-u-yee .this guy TIG welds every thing.regaurdless what he's welding he TIG welds.when i got them back from him and saw them i gave him a whole hearty HELL YEAH!!!!i then sand blasted them clean.
I'll get some pics posted when i get the chance.it probaly wont be till next week i'm working out of the shop all this week

Stay Tuned!!!!!!!!!!

 

Hehehehe !!!!

 

 

Looks good. I'm also kinda partial to the picture in the middle.

 

Hehehehe, Yea baby, that's what I'm talking about.

 

yeah that's my baby girl she just turned 1 this past april

 

Swapmaster what did you use to make that nice clean curve?

 

What curve are you talking about?

 

what did you use to shape the alum. to fit

 

The aluminum is from old core ECM's. I used tin snips to cut the
strips out. I think I made them what, 2-1/4" wide then cut them
a little long then twisted them so they fit the contour of the
runners. Then used the snips to rough the contour on one end
then marked the other end for lenght then used the snips to
rough the coutour on that end. Then twisted them around so
they fit tight then snaped them into place.

Wala. Filler pieces. They were a pain to get right, alot of fitting,
measuring and triming.