Turbo 3800 T56 Grand Prix

[nomoar]

Have you noticed any issues with the power steering pump pressure on the 3800 being too high for the GM steering box? I've been chasing issues with my steering since the swap, wondering if maybe one of them is that the new power steering pressure is just too high and causing erratic steering qualities. I can't find specs on the 3800 pump pressure.

I've seen that people tend to use pressure reducer kits for LS swaps, because those pumps put out way too much pressure. Wondering if you did anything like that on your swap?

Does anybody know how much pressure the gm 800 steering box is supposed to want?

 

[bs009]

I haven't noticed any issues with it at all aside from the typical dead spot on it. I'm planning on switching over to a borgeson box though to solve that dead spot issue though.
I never got a lot of wheel time with the old 4.1 engine but from what I remember the 3800 pump works way better than what the car used to have.

What kind of issues are you having?

 

[nomoar]

What steering ratio do you have?

Mostly it's become pretty twitchy at higher speeds, and the wheels don't want to return to center on their own after turns. Probably I have some alignment issue, but this does feel like something new since the swap. I put a quick turn 800 steering box from a 605 while back, which made it quite a bit more responsive - I wonder if the higher pressure doesn't play as well with the quick turn that wouldn't be as noticeable in a standard steering ratio?

I found this kit which appears to work with steering pump on the 3800 (Type 2? - same as on ls?) https://www.scramspeed.com/products/gm-lsx-steering-pump-pressure-reduction-kit.html
Will probably give it a try.

I still have a bit of dead spot issues like you. I'd love to get that Borgeson, definitely less us know how that goes!

 

[5spdCab]

On the Borgeson pump, be certain of the return line tube location. I ordered a Borgeson universal, which had the return line tube coming straight out the center. It would not work on my SBC because the return line hit the engine block. Whether that had anything to do with the old bracket that I was using (stock bracket from before my v6 to v8 swap) or not, I may never know. I attempted to bend the return line, but it bent the back of the reservoir instead, so I was forced to order a different pump.
As a side note, when I received my second pump, it too was wrong, but that was my fault for ordering for the wrong vehicle. I had ordered the pump that fits a '69 Nova (my 307 engine code says it came from a '69 Nova). Third pump ordered for my year/make/model had the reservoir bolt holes for the pump insert clocked wrong so it to would not work with the old bracket.

I was getting pretty irritated, to say the least. I decided that I didn't have much to lose by taking the pump insert out of the Borgeson unit and installing it into the original reservoir. Too bad I didn't try that way back the first time. During the install, I placed four shims to reduce the pressure, three would have been better. The old pump that I pulled out had three shims I inserted during an earlier swap attempt, and it seemed too easy to turn, I wanted a little more resistance, which is why I put four in the new one.
Side note #2: I also installed a brand new steering gear box at the time of the pump swap.
In the end, I have a new Borgeson pump inserted into the old original reservoir which seems to be working great with no leaks, and I also have two other new pumps that are each contained in the wrong reservoirs for my vehicle.

 

[bs009]

Right now I'm running the jeep cherokee box which I believe is close to the F41 box ratio, but I don't know what it is right now. I've thrown 3 different boxes in here that were remanufactured and all have been pretty sloppy so I figure a new pump is going to solve all of my issues.

I'll admit I've never really paid a lot of attention to the pump situation. It's possible that that could help, I would think the return to center would be more of an alignment situation though.

 

[bs009]

So I've taken some time away from the car, been busy with a lot of other things and needed a break after the mad rush to get the car done for Power Tour. I'm hoping to get the car ready for some cruising before the year ends though now.

Power tour went pretty well for my car at least.

Did the trip this year with a supercharged Montana van and the Lesabre in this picture that has a turbo and a supercharger.

Hotel shenanigans were really disappointing this year, but it was still cool to hang out with people at them

I did end up putting the car on the dyno finally but was pretty disappointed with the numbers it put down. I had a lot of trouble with my boost controller being inconsistent and not putting out the 20 psi I was trying to get out of it. It made about 350 at the tire on 15 psi but it the power peak was way lower in the RPM range than it should've been.

I blame that on my cam timing experiment I did a while back. Basically I had the cam timing retarded 4* to try and take more advantage of my ported heads and ported intake.

Or at least that's what I think the issue was.

One of the biggest issues I was fighting was my clutch though the whole trip. The clutch I used here was one I had from a few years ago when the car had a T5 in it. It's a spec stage 3+ clutch and I guess it wasn't ready for the task or it was already destroyed. The clutch might have been out of balance or something, but it really had a hard time getting the car out of the hole.

So trans is back out and I'm waiting for my next clutch that is going to be way better for this thing than the spec clutch was.

In the meantime I'm going to be addressing the power issue I had with it and I have a few things I'm going to do to it to try and get the most out of the stock camshaft for now.

First fix is a new timing set. I'm reverting back to the stock L67 cam timing instead of the modified L36 cam timing. No more cam timing retard for this one.

Second fix is an upgraded turbo!

On the left is the old Holset HX35. The HX35 I have here is a 54mm turbo on the compressor side and has a twin scroll T3 housing. I'm thinking that I'm really hitting the limit of what this turbo can do when it hits 20 psi (400 WHP) on this engine and a few other people have told me that 400 is really the limit of this on a 3800.
The new turbo has a 62mm billet compressor wheel, twin scroll T4 exhaust housing which has a 3.5" outlet for the downpipe. It's a little larger on the exhaust side but a lot larger on the compressor side. This one should be able to hang with the car hopefully past 500 WHP. With the billet compressor wheel and the twin scroll T4 housing it should also spool pretty fast still.

I have two more things I'm working on too to make this thing come alive a little more but I'll save those for another post once I start working on them.

For now I'm working on getting the exhaust from the turbo all the way back done. I'm moving from a 3" downpipe to a 3.5" downpipe and I'm figuring that I need to go and just upgrade the rest of the exhaust that's currently a single 3" pipe.
So it's going to be a 3.5" pipe down up to somewhere by the trans and then it'll split into two 3" pipes all the way back. 3" should clear the axle still and give me plenty of flow for the next iteration of this car.

The challenge now is getting everything to fit in the place I have the turbo right now and it is tight! Here is the old 3" downpipe:

It was so tight that only pie cuts would give me the tight radius I needed to get the pipe where it needs to go. Really would have designed the whole thing different if I were to do it again because I don't think we even thought about the downpipe when we built it.

So with the 3.5" down pipe I had to get a little more creative. I created what I'm dubbing the Power Vortex

This really was the only way I could get the exhaust to get where it needs to go in that area without doing more pie cuts again. I wanted to stick with mandrel bends as much as possible in case that's the issue too.

Now that I have that done now I'm also going to relocate my wastegates. I've had a crazy hard time getting these things to work consistently and it's because of the angle that they're mounted at off of the exhaust.

Both of them are at 90* angles to the main tubes and the passenger side might even be a lot worse than 90*

When I built them I didn't know any better but now I'm forcing myself to fix them. Hopefully I can get that done by the end of this weekend, but drilling through stainless steel is a real PITA lol
Once this is done I'm also going to be able to run a much larger air filter in front of the turbo too so there's going to be a lot of WIN to be had with these changes!

 

[81cutlass]

Glad to see you are back at it and making some progress!

Did you buy a twin disk for your new clutch?

For tighter bends have you looked at donuts? You need to find a 3.5" sure but they are another option.

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[bs009]

I've never really paid attention to those donuts but I'll have to keep an eye out for those for future projects. The mandrels I bought were the tightest radius I could find but those do look pretty tight.

Yup! I do have a twin disc on the way. Finding a good clutch for this combo has been pretty difficult. I've found that pretty much anything over 500hp is going to need to be a twin disc and there's nobody who makes one for the f-body 3800's.
Now I know that Spec says they can do it to hold 1,000 ft-lbs but with the experience I had with my stage 3+, knowing how my brother's experience was, and all of the things I've been reading about them on forums had me looking for other options.
I went and asked Mcleod and apparently custom clutches from them won't happen.
I asked Centerforce and they said they couldn't do anything.

Monster was willing to work with me though! I shipped them a factory clutch and flywheel for the 3800 so they can take their measurements back in late August/early September.
We landed on an S twin disc clutch for now that should hold 700 tq no problem. I was hoping to run a triple disc but apparently I would need a spacer between the trans and the engine for it to fit. It's a possibility in the future but I wasn't able to find an extended pilot bushing and extended T56 dowels and didn't want to deal with that yet.
Right now I'm planning on running one of their twin disc SC clutches once I do a cam swap sometime next year

Super stoked to have a badass clutch to be able to go into this thing that's actually capable doing what I want it to do!

 

[DRIVEN]

I work with the dyno trailer guy.

 

[bs009]

Small world haha! I live pretty close to the town listed on their banner so you're probably not too far away then.
I'm hoping to hit a local cars and coffee again before the end of the year if I ever get this thing done lol