🔧 BUILD Turbo 3800 T56 Swapped G-body Grand Prix w/ Holley EFI

[bs009]

Okay, I'm just going to do it then

 

[sktchy]

I second it. Lil twist on what everyone else does lol

 

[bs009]

Managed to finally get the downpipe finished today. Took way longer than I thought it would but I managed to squeeze that thing in the tiny area I had for the downpipe.

I'm dubbing this mess of a downpipe THE POWER VORTEX!!

Was a real PITA to figure out where to put the bends at to snake its way down there and where to put the v-bands so I can actually remove both ends of the pipe. This actually came out way better than I thought it would though so far!

Tomorrow I'm hoping to at least get the wastegates tacked into their new positions.

 

[bs009]

Got the wastegates set where they're going to go. This should hopefully allow the wastegates to work a lot better now that exhaust gas is a bit more directed into them.
Also should be way easier to change springs now that they're up high and easy to get to

Here you can see where the manifold splits between the turbo (down) and the wastegate. Should see a lot more gasses flowing into the wastegate than before with this

Lots left to do still. Manifolds are coming off next to finish the welds and clean up any metal shavings inside them.
Also going to change the timing chain while the turbo's out of the way and might as well change the rear seal while all of the fluids are drained.

So my list to get this thing on the road again looks like this right now:

- timing chain
- rear main seal
- finish welding exhaust
- retorque heads just in case
- install new clutch and trans
- build a new 3.5" -> dual 3" exhaust
- swap rear axle
- and all of the little things in between

 

[bs009]

Well I think I found the source of one of the harmonic noises/vibration I was feeling on the car. They flywheel shield was rubbing on the flywheel apparently. I knew it was tight but didn't realize it was that tight. I'll just trim it down now so it's not as tight up against the wheel. I also replaced the rear main seal again while I was at it. I went and bought the dealer tool to set it in there and an ACDelco gasket so hopefully it doesn't leak again.

Verified my cam timing wasn't done wrong from before too. looks like I did retard it the way I thought I did.

I've put it back to the L67 timing though now so that should allow me to get back the top end power that I was missing on the dyno.
Also adding rockers too to this thing. these are ZZPs 1.9 ratio

Moving the wastegates allows me to run a much bigger air filter than what I ran before and won't need to have a crazy tight bend in there to make it fit.
I'm also pretty sure the old warped filter was a huge restriction here too.

Secondary 3 bar MAP sensor so I can actually log boost over 15 psi in uvscan

That one is for a Duramax and supposedly is not that good as a primary MAP sensor since it can't read below 30 kpa. I may end up running it though in place of the two bar down the road if I can get the PCM to read it properly. For now its data is going straight into my DHP box.

Fancy new steering box that still actually leaves some play in the steering wheel

That's a wrap on the exhaust! Or at least the exhaust under the hood

 

[sktchy]

Nice! I thought about running an extra map sensor somewhere and running it to the prolink but I never got that far and I'm not quite sure how I'd get it to transform correctly to read it in vcmscanner but I'm sure one way or another it could be done

 

[bs009]

Nice! I thought about running an extra map sensor somewhere and running it to the prolink but I never got that far and I'm not quite sure how I'd get it to transform correctly to read it in vcmscanner but I'm sure one way or another it could be done

I'm thinking it's just going to be linear reading from 0-5v for 30kpa - 330kpa, but being able to log both at once is going to show me for sure and also how far out it is. I've heard there's more room for error in the 3.3 bar MAP sensor.
I'm new to HPT but I'd assume you can just give it a formula to translate the voltage into a pressure. This sensor was pretty cheap compared to a lot of the others I was seeing though at least!

 

[sktchy]

Well, now at least I know which sensor to grab and what ranges it'll work with for when I get around to messing with it

 

[bs009]

Mostly done under the hood for now. Waiting for my new clutch to arrive still so I started working on the rear end finally.

This is a quick performance 9" rear end. I had them put on axle flanges for a 98-02 f-body so I can reuse my current disc brake setup and save me some money. Also using the GM bolt pattern here too.
Took probably 11 weeks for me to get this thing from the day I ordered it, but it looks pretty good at least.

lot of money in this picture ?

It's looking like I might need to add bump stop brackets to this one, then also the shock relocation that's typical for this disc brake setup. I also have vent filter coming too for it.

Discovered last night that I'm going to need to press on the bearings to the axle shaft because of my disc brake setup here. Looks like the 98-02 f-body brake bracket is going to act as a retainer for the pressed on bearing to hold the axle shaft in.
It makes sense but I wasn't ready to have to do that. Might have to go buy a harbor freight press or something.

 

[Mr_Roboto]

A press is well worth the bucks rarely used but will pay for its self in a job and handy when you do

 

[Mr_Roboto]

Oh, and if the hankering ever hits you can make AKs and CETMEs after.

 

[bs009]

Oh, and if the hankering ever hits you can make AKs and CETMEs after.

That sounds like something I need to do some looking into haha!
Sounds like grabbing my own press is the move then. Might also be able to use it to finally install a smaller pulley on the daily too so it's probably a justified purchase now lol

 

[bs009]

Welp I bought a press. Made this job super easy for sure.

To attach my hellwig pro touring sway bar I needed to mount the brackets to the axle without using the U bolts it comes with because the back brace on the axle would get in the way. Out comes the welder again to make them fit and it's way better than using those u bolts

Also needed to relocate the shock mounts on the new axle too for the f-body disc brakes. This seems like a better way to do it than I did before

3.5:1 Eaton Trutrac

Starting to come together now

Now I just have to figure out if I wanna run bump stops on this too. I could cut them off the old axle but thought I'd try and sell it complete though and see if I can get some money off of it.

 

[bs009]

Finally wrapped up the rear end on this thing. Made a few bump stops using a set of the f-body rubber pieces and then made a tab for the brake splitter.

Car is finally resting on the axle in the back again!
Just need to finish the exhaust before I can get the tires off the floor and bolt them back on.

Another big piece of the puzzle arrived today

This is Monster's most basic twin disc clutch and is rated for 700 hp/tq
Looks really good and I'm stoked to get this thing in the car!

but...

Looks like they zero balanced it instead of matching the weight of the oem flywheel I sent. It's possible the weight is in the pressure plate/second clutch assembly, it is marked to only go on one way.
I'm going to check with them but I think I might have to figure out how to get this thing balanced.
Back when I was trying to do this in August there was nobody local I could find that was willing to do that so I'm expecting this to be a debacle to figure out.

Zero balance would be amazing if I were building a motor and could have it internally balanced, but it's looking like I have yet another hurdle to solve for this thing.
Might be ordering another spec to get the car back on the road again this year if I can't find anyone to balance this thing.

 

[bs009]

Finally found a local place that was willing to properly balance the new flywheel that came with the Monster clutch last week. Sounds like it's going to be a few weeks before they get it all set though. No surprise there with the way things have been going for the last year.

I'm really itching to get the car back on the road soon though. Hoping I can get it up to Michigan to see some family this week so I'm going to button things up pretty much as they are and hold off on the exhaust upgrade until afterwards.
For now I'm going to be installing this spec stage 5 clutch though so we'll see how that works out. Supposedly there's no friction zone on this at all but it should be able to hang in there a little better than the stage 3+ I had before.

I really only have like 2 days to work on this if I'm going to drive it out Friday night so it's going to be an interesting week. I thought I had more time but forget I'm flying out for a work trip tomorrow so I'm losing a few days of wrench time. I'm not too worried though, I think I can make it happen.

 

[bs009]

Well so far it looks like my mad rush to get the car going again is going to pan out.
Since I was so short on time I didn't bother to do the full exhaust upgrade I was planning on doing, but I was at least able to get the 3.5" downpipe to connect up into the old 3" exhaust. There were so many little things I had to do that took forever, things like boost control lines, driveshaft u joints, and shoehorning a 3.5" downpipe with oxygen sensors in the tiny amount of space available. I was up until 3am last night working on this thing before I finally fired it up.
It's finally back on its own wheels again though

Fired up the car again last night for the first time since August and had nothing too crazy happen. The exhaust is way quieter than it was before now that I've switched over to the MLS exhaust gaskets installed new bolts with these wedge lock washers.

Amazon.com: Wedge Locking Washer Carbon STL Zinc FLK CTD Thru Hardened M8(5/16) Large O.D. 20 glued PRS/Pack : Industrial & Scientific

Amazon.com: Wedge Locking Washer Carbon STL Zinc FLK CTD Thru Hardened M8(5/16) Large O.D. 20 glued PRS/Pack : Industrial & Scientific

www.amazon.com

Hopefully those keep the manifolds from coming loose again this time.
I did notice a really loud lifter tick when I started the car up. Eventually it did get quieter but I can definitely still hear it.
For some reason the car is also throwing a P0121 code which makes no sense to me at all. I'll have to try to track that down tonight before I do a test drive before leaving for Michigan tonight. Hopefully the lifter tick will eventually go away, I can't remember if I put in the newer LS7 lifters in this engine or if it still has the lifters I installed into it 70,000 miles ago when it was in the Regal. My guess is they're just whining about the LS6 valve springs though and just need to get some oil running through them.
Car's had a lot of changes since August so hopefully it all holds together.

 

[v6buicks]

I'll be interested in hearing how much they help. My SS bolts have backed out on me twice.

 

[sktchy]

? I just used stock bolts and blue loctite

 

[v6buicks]

? I just used stock bolts and blue loctite

I like stock bolts better than the SS kit. They're ugly but the heads are bigger. I've come close to stripping
my tiny 10mms out.

 

[v6buicks]

Plus the SS kit is dumb and doesn't include a replacement for the stud bolt where you attach the dip stick. I reused the stock part for that one spot.

 

[sktchy]

Glad I went the route I did then. The MLS gaskets and a lil orange goo seemed the superior road to me

 

[bs009]

I've had pretty good luck with the stock bolts but I'm having to use stainless socket cap screws because of how tight everything is in here. Even with those it's still a pita to remove the manifolds though
I'm hoping to fix that in the future though

My truck though is a whole different story. I have to tighten the stock bolts every oil change because 1 or 2 like to get up and walk away. I have a few spare lock nuts though I'm going to throw on there and see how they work.
The old guys I've talked to about this though recommend this type of lock washer. Not sure if it's the same exact one though.
Never considered lock tight though, always figured it would be too hot for it

 

[sktchy]

It probably is too hot for it but I generally don't think about things like that until after the fact ? I do know the cartuning pipes are a royal pain to get a wrench on in spots and there's a couple that you have to use the box end on and go an 1/8 turn at a time and for those I nipped the excess off the tops of the stock studs so I really didn't wanna have to mess with them til I pull the motor again.

Spark plugs are just about as much fun to get to

 

[bs009]

So I took the car around the block, new turbo lights off crazy fast but that might have more to do with the new rear end though than the turbo. It sounds way different than the old one, sounds like one of those electric turbos that Cleetus tested on his cobalt a while back.
The exhaust note sounds ungodly amazing after all of that exhaust work, a 3800 should not sound like this at all . Sounds a lot like an RB motor now IMO, I'm going to have to put together some videos or something.

It is misfiring really bad anytime I put some load into it though. I'm pretty sure my plug gap is down to like 0.020" but I'm going to let the car cool off for a little bit and swap out the plugs before I try to leave tonight. Maybe that'll solve the issue but who knows

 

[GTPpower]

I'm sure the exhaust note is due entirely to that downpipe routing.