I'm familliar with Porting, but I've never heard of siamesing.
Could someone explain this to me, and maybe list some of the pros and cons associated with it.

Thanks

 

Basically, Its taking your stock OEM runners
from your TPI unit, and welding patches of
aluminum to "join" the 4 individual runner tubes
together. After its complete, you will have 2
large runner tubes on each side of the unit..
Instead of 4 tubes.. I dont reccomend
fabricating your own.. as after-market
siamesed runners are readily available.

If you scan down to the :
"Post Your TPI paint scheme" Thread,
Tenpin posted a picture of his Siamesed
TPI 305, that will give you a better idea
of What I just said.

As for performance, Its not a "Must-have"
when building TPI motors, but.. They sure
can give some up-top ponies if matched
with the correct intake manifold

 

Thanks

 

top left would be what siamesed intake runners would look like

top right would be what siamesed cylinders would look like ( like a 400 )

bottom left and right would of course not be siamesed or basically share a wall to keep it simple

siamese would save space, making siamese where there is none - such as intake runners would increase the volume, in the case of cylinders in the block siamese would be a potential weak spot and in case of 400 help it run hot

 

There we go, that should do it!!

 

Here is an inside pic of my ported Siamesed SLP runners

Hope that hepls

 

Thanks everyone. They look like they were cast that way. To wld them together and have them look that good seems to be impossible.

 

Well actually, since the runners are made of high grade aluminum,
you can TIG weld to fuse the aluminum together. There was a few
pictures awhile back of someone who did this, and looked rather cool.
A properly ran TIG bead looks very pleasing to the eye..

But, Thats why I stated before its much easier to purchase a
set of aftermarket runners of your choice.. Im sure there is a ton
of topics on the matter.. use the search function.

Nice close-up shots Stubbs

 

yea i was doing mad reaserch on this i found out you can add mad horsepower for cheep. if you get a new bbk 58mm TB and SLP runers, you can siamese your plenum, runners and intake manifold to get reat power. like people were talking anywere from 40-60 hp at the wheels. dunno fi this is true but il find out. forting your runners and plenum and intake is really easy. go slow, and you will be done in a week. do you know about your restricive plates in the plenum? do a serch in thsi you wil learn alot like i did!

 

58 mm tb would be a waste of time and money @ that power level. The stock tb doesnt become an issue until ATLEAST 400 fwhp

 

I did all of that, I bought a second plenum and had the plenum fully ported(including opening up the sides so that it is now 4 large openings instead of 8 small ones, its exactly matched to the opening in the pic I posted of the ported runner) and matched to my 58mm TB, the SLP runners were ported and gasket matched to the plenum and also to the ported TPiS Big Mouth lower intake manifold. Total cost(including the port work but not including the TB) was almost 1100 dollars. I never had it installed and now it appears I may be going with a MiniRam since it will soon be EGR compliant so I can run it legally I will most likely sell the full modded TPI setup(no TB), I'm looking to get 1000 for it if your intrested.