Turbo and big HP, what intake manifold are you using?

[GuillaumeC]

I think I've done everything I could with the stock heads and intake on my Caprice... time for something better.
I'll be upgrading to AI CNC ported 215cc Trick Flow heads and I'll need a new intake manifold.

Right now I'm having distribution issues with the stock intake, the spark plugs get darker on the back cylinders...

I has thinking about converting the heads to standard SBC bolt patern and get a Victor E intake with the Nitrous Outlet elbow.

What have you guys done and are you happy with the results?

[Fastbird]

Ported LT4, no complaints.

Posted from my Rooted and ICS'd Rezound

[JCzNova]

Ported LT4, no complaints.

Posted from my Rooted and ICS'd Rezound

I think someone on here has one of those for sale too ZOHAN

[ZOHAN]

Imagine that!..;)

Making you silky smooth...

[shownomercy]

Converted single plane, low profile edelbrock elbow, and a 90mm throttle body.

No issues so far

[GuillaumeC]

Ported LT4, no complaints.

Posted from my Rooted and ICS'd Rezound

How much boost are you running? Have you compared front vs rear plug color?
Just wondering how's the distribution on a ported LT4 intake vs the stock LT1.

[popo8]

BIG CAT

[popo8]

BIG CAT

[popo8]

BIG CAT

[BIG CAT]

I think I've done everything I could with the stock heads and intake on my Caprice... time for something better.
I'll be upgrading to AI CNC ported 215cc Trick Flow heads and I'll need a new intake manifold.

Right now I'm having distribution issues with the stock intake, the spark plugs get darker on the back cylinders...

I has thinking about converting the heads to standard SBC bolt patern and get a Victor E intake with the Nitrous Outlet elbow.

What have you guys done and are you happy with the results?

definitely sounds like the back is starving for air.
we ran a home ported lt4 intake. currently we are in the the process of switching over to a victor efi. elbow is a 102mm 6061.com piece and a 102mm ebay throttle body.
bolt pattern wise i drilled and tapped my heads for the inside bolts of a std intake. the outer 4 i milled the intake because its was the easiest way to get it done.
i have a bunch of pics in this thread.
http://ltxtech.com/forums/showthread.php?23049-let-the-last-min-thrash-begin

[popo8]

Thanks big cat.

LTXtech.com is my drug.

[Fastbird]

How much boost are you running? Have you compared front vs rear plug color?
Just wondering how's the distribution on a ported LT4 intake vs the stock LT1.

Up to 20 PSI so far, no discernable difference in plugs.

[popo8]

Im just wondering... what TB are you using, and have you checked the IAC passages if using a TB with the IAC done right. WHen I went to the monoblade... we had to cut out the IAC passage, weld it shut... then plumb our own using some braided line and AN fittings. Plugs are always even now....

[Flyinz]

PoPo, do you have any pics of the work that you did to that passage? I MAY have to do that to mine, my plugs aren't even and I dont remember doing anything to my IAC passage.

[popo8]

PoPo, do you have any pics of the work that you did to that passage? I MAY have to do that to mine, my plugs aren't even and I dont remember doing anything to my IAC passage.

Ill have to go through my FB...

[Flyinz]

I've got my intake ported for the Monoblade that I bought from Taner, but thats it.

[popo8]

Here are a bunch of pics.. u will see where we filled and cleaned the opening.. then located where we could tap the TB, and the underside of the Intake opening to hit the IAC passage... then it was a matter of making it all fit.

26198262132621226211262102620926208262072620626205 26204262032620226201262002619926214

Sorry they are out of order.. but you hopefully get the idea.

[Flyinz]

Yep, thank you!

[GuillaumeC]

Im just wondering... what TB are you using

52mm BBK, not sure how the IAC is plumbed.

[popo8]

bbks have issues iirc...

LTXtech.com is my drug.

[BIG CAT]

What ecm? I never had a problem and we run a bbk 58mm and fast classic.

Sent from my SPH-L720 using Tapatalk

[popo8]

I think it was Fastbird that mentioned issues with the bbk... or maybe it was @tubbyz . one of them said something about modding those tbs to make the iac right....i think.

LTXtech.com is my drug.

[GuillaumeC]

What ecm? I never had a problem and we run a bbk 58mm and fast classic.

Sent from my SPH-L720 using Tapatalk

Fast classic.

The problem isn't with the TB/IAC, I've had that TB on different motors and it wasn't causing any issue. The problem is with the rear cylinders not getting enough air at high boost.
I'm pushing around 18-20 psi right now. Before the turbos, all 8 plugs looked the same. Now the more boost I run, the worst it gets. With 8-10 psi all 8 plugs look the same.

I'm thinking that that the front cylinders are actually seeing more pressure than the ones in the rear.

I think the better flowing heads will only make this much worse.... it's time for a single plane I guess!

[popo8]

Fast classic.

The problem isn't with the TB/IAC, I've had that TB on different motors and it wasn't causing any issue. The problem is with the rear cylinders not getting enough air at high boost.
I'm pushing around 18-20 psi right now. Before the turbos, all 8 plugs looked the same. Now the more boost I run, the worst it gets. With 8-10 psi all 8 plugs look the same.

I'm thinking that that the front cylinders are actually seeing more pressure than the ones in the rear.

I think the better flowing heads will only make this much worse.... it's time for a single plane I guess!


OHHHH,I guess I automatically assumed you meant during idle... Im def not in the same boost range or HP as you.... but Im running AFR227 eliminators with an edelbrock LT4 intake, and plugs are even.

[blkchevyz]

you would think with it being pressurized that all the cylinders would get the same amount of air. assume you have the egr blocked off?

[GuillaumeC]

Yes, EGR blocked off...

I have a feeling that there is a pressure drop going towards the rear of the intake because of its design.
Maybe a larger plenum volume and bigger TB would help?

I like the idea of the single plane because each runner "feeds" from the same spot in the intake. I'm pretty sure the pressure will be even on each runner that way.
I think having the runners in-line after the trottle body probably causes a pressure drop on the back cylinders, but I have no real data to back this up... only the spark plug color.

[GuillaumeC]

a year later, here it is! cwm4




Modified Victor E manifold.


Bolt patern modified to LT1 specs.
Thermostat housing and coolant cross-over removed.
Ported to match AI TFS 215cc heads




http://i121.photobucket.com/albums/o210/mtl9c1/RX7/IMG_3102.jpg


http://i121.photobucket.com/albums/o210/mtl9c1/RX7/IMG_3103.jpg

[englundjd]

I like shiny new things lol... have you installed it to see if it solved your distribution issue?

[GuillaumeC]

Not yet, this is part of a new build.

I'm going with different heads, turbo, cam, etc... even a different car. :)

Check out the build section for my thread.

[BIG CAT]

intake looks good. depending on who's elbow you run. watch the flange for overlap. i had to mill a fair amount out to get a perfect match with my 6061 elbow.

[GuillaumeC]

Thanks for the info, I'll watch for overlap. I'm using the nitrous outlet elbow.