I bought a 1988 iroc-z with the 5.7l/700r4 combo and it has a stealth ram intake on it. i just have a few questions about all the damn vacuum lines and misc stuff.

1. On the throttle body do both of the ports need to just be pulged off?

2. On the back of the plenum there is another three ports.. 2 of them are blocked off, and the other goes to a pcv valve. is this correct?

3. There is a opening on my left hand valve cover near the coil (if your faceing the engine from the front) And theres nothing there... what goes there if anything?

4. Can i remove all of the smog comtrol crap from my engine compartment since the stealth ram dosent have a EGR valve?

If you cant understand what i typed im sorry that i dont know alot of the technial terms for this stuff.

No. One of mine goes to the PCV valve on the valve cover, and the other to my adjustable fuel pressure regulator.
One can be used for cruise control vacuum, the other for break booster for vacuum and the last one can be where your IAT sensor goes.
This should connect to the throttle body....the top hole.
Yep, the HSR does not have EGR provisions.







Hope this helps....

It seems whoever did the HSR mod to my new car really didnt take much time to do it right and just did not care... Your input has helped me greatly, but im still a bit confused... im at work right now but when i get home i will take some pics of my setup so you can better see what was done wrong and hopefully tell me how to sort it out. Thank you! Im thinking they put the fuel rails on backwards cause my fuel pressor regulator is on the back right side by the brake vacuum deal... and its connected to the back of the plenum from one of those ports...

Actually, the fuel rails can be mounted either direction on the HSR....most prefer to run them opposite of mine. I just didn't want my connections to be by my distributor - less risk of fire.

Post your pics and we'll help you from there......

Will do. by the way your car is super nice man. Good job. Hopefully mine will look that good someday.

Thanks man....I'll stay tuned.

Heres some pics. i didnt do this so yeah... it looks bad. theres a bunch of wire stuff unhooked to... no ideal what it is. but the car runs pretty good... but i know it can run better.

1st Picture - Everything looks fine, except I don’t see where your IAT sensor is located. Mine is plugged in where the red tube blocks yours off.

2nd Picture - Plastic connection laying there is a connector for a 9th injector, to help with cold starts. This was used on the factory TPI intake, a HSR doesn't have that provision so you won’t need this.

3rd Picture – The open hole on your valve covers needs to run to your throttle body and connect where the black plug is.

4th picture – The black plug goes to the valve cover PCV valve. The grey plug on the throttle body can be used for vacuum if needed. The open hole below the grey plug is used to pass coolant thru the throttle body to help cool the throttle body. Most people just bypass it when installing a HSR, which is already done on your car. Look at my pics closely you’ll see my setup is the same. I also see two connections to sensors laying there, next to your injectors. Those both look like coolant temp-sensor connections for your cooling fans. One fan is controlled by coolant temp in the intake, the other is thru the ECM. The previous owner must be running both of your fans together, probably thru the ignition.

Take a look at your fans. How do your fans run? Manually via a switch? Do they start running once you turn the key?

Where is your brake booster line connected to?
Check that the IAT sensor has been installed in the underside of plenum.
To reduce hose runs some install the PCV line to the port under the HSR plenum ( closer to PCV valve ) and move the IAT sensor to a rear port

Line to pass side cover is PCV supply air , hose goes to top port on TB ( no vac )

Stock that port is vac for canister purge , the line from PCV valve runs direct to the vac port on the intake ( drv side )

His brake booster appears to be connected above the driver side PCV connection.
I just noticed - he does have a sensor going to the underside of the HSR - probably his IAT.
That's how I did mine - Sensor in the back - PCV line underneath.

You're correct - I edited that.
Yep. I have no vacuum canister on my car - HVAC has been removed.

I was going by his quote
" On the back of the plenum there is another three ports..
2 of them are blocked off, and the other goes to a pcv valve.

Okay, I see. Looking at his picture, it appears he does have "two" vacuum lines connected. Is that what you're seeing?

My fan's run fine.. one of them runs off of the ecm and the other a switch.

The IAC sensor... is that in picture #2 directly in front of the fuel rail?

The yellow vaccum plug on the back of my plenum in picture #1 im going to run that to my FPR i just figuerd out the car is running rich so that should fix it

On the pass side valve cover... the open hole there im just going to buy something to put in there, since i allready have a PCV valve on my drv side valve cover connecting below my brake booster vacuum.

Okay, that's fine.

No, it's actually in pic #4 directly in front of that open coolant hole.

Yep, that sounds good.

I believe you should have a PCV breather connection on both cylinder heads, not just one.

Ok, ill hook up that other pvc valve today to the top port on my throttle body.

What is pluged off in front of my fuel rail in picture #2? im not sure what it is but its a little vacuum line pluged with a screw.... looks like its under my intake... not sure.

So my IAC sensor is fine?

Thank you for your input heatseeker and Vetteoz!!!!!

I believe that is the vacuum line that would connect to the bottom of your TB. (see link, its plugged off in pic)
http://www.eecis.udel.edu/~davis/z28.../58mmfull2.jpg

Yes, it's fine.

You're welcome! Glad we could help you out.

Would that run to my distributor for timeing or something? And thank you again.

No. There are no mech vacuum advance lines for computer controlled TPI cars. Follow the plugged end from under your TB and see where it goes.....

So to sum it all up and to make it eaiser to read... could one of you tell me where everything should be hooked up on my set-up? i would really appreciate it! Thanks!!

Did you LOOK at the vac diagram I posted for you above ???

Once again ,that vac line ( from underside of TB ) to tank pressure valves is shown in the vac diagram

If you seal that hole off ,CCV won't work as intended and you will get sludge/ condensation buildup in your engine
If you put a open breather there you just create a big air leak into the intake that makes problems with MAF ECM's ( think bad idle )


You only use one PCV valve as shown in the vac diagram, pass side is just a fitting for the hose from TB to connect to

So run a hose from the top TB port directly into the pass side valve cover hole with some type of fitting? because after i run the car down the road and open it up a bit then pull back in and put the car into park it idles high, but when i first start it up it idle's fine, and if i shut the car off after i run it hard the high idle seems to stop... Once again i appreciate your input vetteoz and i did see your diagram. Thanks!

Typical of a vac leak ( that you have with unmetered in going in the pass side cover to the PCV )

So that hole in my valve cover is makeing it idle weird? if i run a vacuum hose from the top port of my TB to the hole in pass side valve cover (with no pcv just a hose/fitting) It should fix it?

One of several possibilities
Has the IAC valve ( that controls the idle ) been set?


Just like the vac diagram I posted above shows!

Im not sure if if the IAC has been set or not, i just got the car a few days ago.

So CCV is cruise control vacuum? do i need to goto the parts house and buy a CCV plug for my pass side valve cover? If that exist?

Also my canister is gone. thank you!

(To reduce hose runs some install the PCV line to the port under the HSR plenum ( closer to PCV valve ) and move the IAT sensor to a rear port)

The IAC has vacuum that needs to be hooked up?

No
The IAC is the electronic device under the TB that the computer uses to control the idle speed.
Often has to reset when major mods are made to engine

Hey Heat seeker how did you use manage to use that strut brace and get it to clear the HSR?

Is there any need to plus the coolant passages on the throttle body if they aren't used/ don't they just make a quick loop and not tie into anything else?

Hey, sorry for the late response. Actually, I had to wrap it with a towel, put some boards on the ground and drive up on it with my F250. I had to bend it to get it to arc over the HSR. My hood is an aftermarket hood which has more clearance than a stock hood.

Hope this helps.

Thanks !! I've never thought of bending one ive been debating making my own or buying an aftermarket and adding spacers under an aftermarket one since I have extra clearance w/ my hood too