Charlie Robinson's '99 Riv

Weird. i checked the chart and it was using the sensor: MAP. I changed it to PID and the MAP values look like kPa now.


I can only seem to pack 7psi with the 3.25" pulley.

I dont think I can get 20 degrees of advance without gushing fuel or getting KR either.


So i can either get ~7psi with ~15 degrees of timing
or I can get ~6psi with 20 degrees of timing.

Need to go the track and test both tunes.

MAP is vacuum, or pressure, which is also boost. (+) values are boost. (-) values are vac. The engine doesn't have a boost sensor - it uses MAP to calculate. A vac leak will raise MAP value, especially at idle. If it's a bad leak, it could decrease boost, but I don't know how much.

Anything with a higher lift on it (your Cam) will change vacuum at idle, yes. That's why uber high-HP cars with crazy Cams need a separate vacuum pump. The engine produces almost no vacuum at idle and the engine wouldn't run without the external help. That's also why they tell you to raise the idle a bit when you install a Cam. Not only does it smooth out the idle (which sucks cause I love the lope), but it helps the lower vacuum numbers.

So i pulled both Ts (there are only 2, right?) 1 by the fuel rail and the under in the LIM under the snout?

The one by the fuel rail I already knew had a nasty gash. I patched that bad boy up with electrical tape.

I was shocked to find an even bigger gash in the LIM T.

I patched that one up as well and I am curious to see what effect this will have if any. the gashes were not wide open and the vacuum wouldnt be pushing them open from the insides but they were DEFINITELY not sealed tight.

I also switched back to the 3.4" pulley.

I need to get a wide band asap.

I am now pushing a hair over 7PSI with the 3.4"!!!

The leaks in the 2 T fitments were losing a pound of boost!

I wonder what the 3.25" would push now...!!!

i know I cant get the timing I want with the 3.25 so im not even gonna try.

But yeah, 7PSI with the 3.4 @ 20 degrees timing advance WOT

I am still trying to summon the courage to take the front valve cover off and pull a push rod for a pic.

If it makes you feel any better Charlie, I'm trying to sum up the courage to do the coolant elbows. It shouldn't be to bad of a job but I've never torn into an engine before (unless you count lawn mower engines).

Bro, I did the coolant elbows in the first year I got the car. And I am super serious when I say, if I can do it, anyone can do it. But before I tell you about that, let me give you some back story.

My riv is the first car i've ever worked on. I got it in 2011 and was ultra noob status with 0 car knowledge and 0 car experience .

Here we are 3 years later and I am still a noob.

Here are my greatest solo job accomplishments:
Changed out both LIM elbows. 2011
Changed both rear shocks. 2011  AA advised with a phone call.
Changed all sway bar links. 2012 
-these are greatest because if i messed up, i wouldve either died, became seriously injured during install or while driving after install, or wouldve effed my car up.
But I did all 3 with no supervision and everything is still 'good'.

other notable accomplishments Im proud of but werent as life threatening.
stereo receiver relocation and subwoofer install. 2014
FWI install. cutting out the hole in the engine bay. 2013

other accomplishments im grateful for that i bitched out on and people helped me
spark plugs - thanks to abaddon, cause im a bitch. I still dont feel confident doing this although Scott did show me what gapping plugs was all about. So that was something I didnt know..I will try it some day. The back plugs terrify me still.
door handle install - thanks to sir psycho sex, cause im a bitch and he had already done it prior


accomplishments im grateful for that i couldnt have done solo because i just didnt have the tools.... So I can excuse myself for being a bitch on these...
stock pulley to MPS pulley hub - supercharger chuck
engine rebuild - bill the baller
brakes - hood rat with tools on craigslist. 
exhaust , struts, springs, and sway bar installs - the shop down the street. Mostly didnt have the tools to do these but it's reall cause im a bitch and paying sounded better than struggling.


so thats my noob history with working on cars. I try to act like im a cool car guy that knows alot with a lot of experience but im just fronting. Im a noob and probably will be for the next 5-10 years.

Ok. on to the coolant elbows. this probably should go in the appropriate thread but here's what i did.

Went to moms house to use her garage cause i live in a ghetto apartment.
drained the coolant. realized i was committed. Had a party to go to that evening so there was no backing out.
started at like 6pm.
took off the belts, removed the alternator, took a piss cause i was so excited i was doing real man shit.
pulled off the junk elbows and put the new ones on, put everthing back together and locked it down.
said a lil prayer and filled the coolant back up.
started it, said a lil prayer that it wouldnt fail, and went to the party.

it has been good ever since. looking back on it, it wasnt that tough of a job but with no experience, everything seems intimidating.

Like most things in my life, the words I use most often before diving into something is, 'fuck it'. 

it works very well at initializing most of all the endeavors ive ever undertaken and have been proud about.

So my advice to you is to just say 'fuck it' and change your LIM elbows. you'll be fine.

I'm free this weekend if you want to tear into it man. Coolant elbows suck because it's a mess, and both times I've done it the plastic was cracked and I had to get creative to get the broken pieces out lol

I agree with Charlie. You have to look at things in steps rather than as one big job. It makes everything in life a lot easier.

If you want to drive down here and help, come on over. I think through all the pictures and such I'll be fine though.

matt270avian wrote:

If you want to drive down here and help, come on over. I think through all the pictures and such I'll be fine though.

Sorry, I wasn't very clear with that, I meant Charlie

Charlie, read through the long post and all that I took away was, "hoodrat with tools on Craigslist."
Guessing she wasn't hot, or that would've been worth a note. In all seriousness I'm spoiled because I work at a stealership and I trade beer or gun advice/cleaning for work on my Riv. You guys do get me motivated to take on the small stuff, PLOG install, airbox gutting, etc. Still a noob, but thanks for giving me perspective.

Looks like you figured it out. It makes sense the soft elbows would leak a great deal more when boosting. The boost is sorta blowing them apart. Vacuum was actually holding them together to an extent. Those things gotta be right when you got + & - pressures in 'em.

Have fun tuning

turtleman wrote:

Looks like you figured it out. It makes sense the soft elbows would leak a great deal more when boosting. The boost is sorta blowing them apart. Vacuum was actually holding them together to an extent. Those things gotta be right when you got + & - pressures in 'em.

Have fun tuning

Thanks, turtleman
I was losing a solid pound of boost because of the leaks in the rubber Ts!

I assume I didnt have enough vacuum to pull the BBV all the way down and thats why my boost #s looked short.

Next challenges I face are:
determine if tapping noise is anything real
        get a pic of a push rod for ZZP
try to fix steering wheel so its nice and tight
polish supercharger
get and install brake pads

charlieRobinson wrote:

I assume I didnt have enough vacuum to pull the BBV all the way down and thats why my boost #s looked short.

more likely the leak was interfearing with your map reading too. I believe that elbow circles around into your map. The bbv drops right in under *any* load and only blips back for shifts. A leak at that T would cause low readings from both your MAP and any mech boost gauge. IE, your engine was probally seeing higher boost, just no sensors picking up, and might have been slightly lean as a result... but its all guesswork get new T's, get more going on than electrical tape. If you are modding, and tuning, all parts, especially sensor lines need to be right!

My 3d printer was shipped to the chicago office..... not happy about that.. i was making some sweet stuff.. but i wanted to print with a flexible media and make some new Ts.

The electrical tape bandaid seems to be working great.

That ticking noise I mentioned earlier; after some research, I want to believe it's an exhaust leak. I still need to investigate.

Anyways, after fixing the Ts I noticed a pretty big difference in my MPGs?
I do about 80% city 20% highway driving. 

Average MPG. I usually fill up once I use a half a tank which usually yields 120-160 miles.
9/4: 16.5MPGs
9/7: 15.5 MPGs
9/12: 13.97 MPGs
9/15: fixed vacuum leak
9/18: 17.8 MPGs!!!


Like I said, I have a feeling I may have an exhaust leak that is affecting my O2 sensor and creating a false lean condition which is enriching fueling erroneously. Hopely after I search and destroy this leak, I can get my avg mpgs to 19+

charlieRobinson wrote:

Like I said, I have a feeling I may have an exhaust leak that is affecting my O2 sensor and creating a false lean condition which is enriching fueling erroneously. Hopely after I search and destroy this leak, I can get my avg mpgs to 19+

The leak would have to be before the O2 for that to possibly happen. So, it's either a crossover or manifold leak assuming your O2 is in the factory position.

Inspect closely the vacuum line to the fuel pressure regulator, and test your fuel pressure with the vacuum line off (and plugged). It should be about 50.

I picked up a cheap fuel pressure gauge at AZ for about $25 on sale. It's worth knowing. It should have a fitting that screws onto the injector rail.

Low fuel pressure would create a lean.

An exhaust leak would also create a lean, but you would hear that. Do you have an audible exhaust leak near the engine?


edit - afterthought - all of these things need to be in good shape before you start tuning. So any tuning you've done, you may want to back up and start over.

yes, i can hear the 'ticking noise' right out the drivers side. I have to imagine it's a leak around the cross over. I thought since day 1 after rebuild it was valve train noise. But after all the reading and videos ive listened to, I think I have an exhaust leak.

The 'ticking' noise only happens under throttle. At idle or coasting, it's silent. 


I see people spray suddy water over the pipes, then start the car and watch for bubbles?

Is this the best way to track down a leak?

I dont have a stethescope but I tried a screw driver and got no results with that.

Try a 4 foot piece of garden hose - hold one end near your ear, move the other end around by the exhaust pipes. That way you don't get burned!

I usually just hold my hand around the pipes while they are cold at startup. You get about a minute to find something before they are too hot to touch.

deekster_caddy wrote:

Try a 4 foot piece of garden hose - hold one end near your ear, move the other end around by the exhaust pipes. That way you don't get burned!

I usually just hold my hand around the pipes while they are cold at startup. You get about a minute to find something before they are too hot to touch.

Thanks, Dr. Deek. This worked perfectly. Found that the sound was irrefutably coming from the front exhaust manifold DA PLOG and the valve covers sounded very peaceful.


Went to Tyler's house today and blam!

New gasket fixed 80% of the issue.
Still have a crack around one of the runners.

Time for headers!

Dear ZZP, why must your headers be so darn expensive?

Please Lawd, let me come across a good deal on some used ones.

Dibs on the cracked plog

Also:

http://www.grandprixforums.net/threads/92334-Pacesetter-Headers

http://www.grandprixforums.net/threads/91479-SLP-Headers-Gen-V-XP-Cam-Injectors-IC-pump

Gotta be those 304 ZZP headers, brah. The power log has your name on it.

I wanted to document this god forsaken noise before the headers are installed and hopefully my ride starts sounding healthy again.


Here's what i've been listening to for the last few weeks everyday.

After my engine was rebuilt, Bill did not securely bolt down my PLOG. That was one cause of the leak. At the same time, I also discovered the runner on the right side of the PLOG had a ring crack around it.

After the bolts were tightened it up, it helped significantly. I also had my mechanic put a ring of weld around the runner. This helped a bit too but also changed the tone of the noise.

Cannot wait to get those headers installed....

That sounds nasty man. I'm sure you'll find the source when you take it all apart.