Stock upper intake manifold mod (Page 1/4)
zobari MAR 01, 12:27 PM
Hi,

I have modified my second upper intake v6 manifold

There are the pictures :

(Thanks Patrick for the picture resizing advice)
















I hope to get better upper rpm and get extra some hp

I have made some other mod and maintenance like exhaust manifold porting, removing cat, sport round muffler and stainless Steel full custom exhaust. Accel Ignition coil performance, performance SPARk câble, ngk new iridium SPARk plug, kn air filter and others oil and gas kn filter, no egr.m, New oil castrol titanium 5w30 with a9 motoreco vl oil additive, All sensors are New, New clutch and oil pan, Idecarbonized the engine with liqui moly intake 5111 and then with a tunap 133 intake bottle.. .

I let you know when I Will install This intake but at the same time I Will change the injectors

[This message has been edited by zobari (edited 03-02-2019).]

pmbrunelle MAR 01, 12:47 PM
For sure it will make a difference.

With a stock 2.8 (except for ported exhaust manifolds), I have observed an absolute pressure of 85 kPa in the plenum at WOT.

Therefore, I take the hypothesis that there is a 15 kPa pressure drop across the throttle body and neck.

Hence, I would suppose that if you succeed in maintaining atmospheric pressure in the plenum at WOT, you could increase top-end torque by 18%.
zobari MAR 01, 01:22 PM
Ok thanks for your response and that's very interesting. For me.

I Will proceed to the installation This month with the 6 accel 15 lb injectors replacement.

I Will maybe get my 88 gt dynoed next month after the modification.
Patrick MAR 01, 11:24 PM

quote
Originally posted by zobari:

There are the pictures...



I'm amazed that individuals who are wizards in the shop often have no clue how to properly resize and post images.

I felt this custom intake was rather special... so here's Zobari's images re-posted so that we can all see them.

[EDIT] Zobari has now copied and pasted the six images I re-sized into his opening post (which is what I was hoping he'd do), so I've deleted them from here.)

[This message has been edited by Patrick (edited 03-02-2019).]

Spadesluck MAR 01, 11:30 PM
Will the non aerodynamic square hurt air flow, thoughts? Or will it allow more air to be in the manifold for the motor to take in?
tshark MAR 02, 12:12 AM
Will the top clear the deck lid?
pmbrunelle MAR 02, 12:17 AM

quote
Originally posted by Spadesluck:

Will the non aerodynamic square hurt air flow, thoughts? Or will it allow more air to be in the manifold for the motor to take in?



The concept of a large plenum full of relatively "still air", ready for consumption by each cylinder, is a common concept...

See Ferrari:


Honda:


Previous incarnation of La Fiera's car (which produced good power):


Toyota went against the grain here. I haven't seen other cars like it!

[This message has been edited by pmbrunelle (edited 03-02-2019).]

zobari MAR 02, 02:38 AM
I have take the wcf intake manifold as example with my custom touch for the back side and also for the upper side.

I have paied 180 dollar for the weld working.

I think that the wcf intake is too expensive.

I Will clean and repaint it in red as oem color

[This message has been edited by zobari (edited 03-02-2019).]

Blacktree MAR 02, 10:23 AM
I was going to compliment your welding skills, but I see you hired a welder.

Like mentioned above, the purpose of an intake plenum is to be an air reservoir for the cylinders. The stock plenum has very little volume, so there isn't much air for the cylinders to draw from. The larger volume will allow each cylinder to take in more air during the intake stroke. And that will improve torque.
zobari MAR 02, 10:36 AM
yes exactly the first restriction is the neck and then the volume is very thin and insufficient for a v6 engine i think

The trueleo intake will be maybe a bit better in performance but it's very expensive.

That's my last mod on my 2.8 v6 engine

[This message has been edited by zobari (edited 03-02-2019).]