L26 U Van Series III Update

[Jr's3800]

Been 2.5 years with the 3800 Series III L26...

Comp Cam NA Performance Cam
LS6 Valve Springs
Comp Valve keepers
Comp Retainers
Ported Lower intake
Magnaflow HF Cat
Magnaflow Muffler
GX3 4T60E
1997 OBD2 PCM
On and on bla bla bla...

After 2.5 years the engine still runs great and burns no oil at all.. Starts the first time every time ... I have towed as much as 4500 Lbs a short distance... Picked up motors and transmissions... Concrete.... Its still super practical and still turns a few heads when they don't expext the Minivan...

The problem is that the Trans is taking a crap... The Forward/3rd Roller Sprag is taking a dump and not holding... Trans has done 25,000 miles of abuse... After much research it turns out that the failure is common and the 3rd roller sprag should be replaced during a rebuild... Book says inspect, reuse if ok... Bla bla bla... I guess you learn by doing...

so my next step will happen very soon... I have a 1997 4T60E SRTA GM Trans... I am going to pull the guts out of it and install a 4T65E ring gear and Diff.. and reassemble... I am going to the 3.05 Diff as opposed to the 3.33 I currently have... The 3.33 was fun, but I think the torque produced by the cam is more than enough to turn the 3.05 gears and get some more MPG's as well...

As well due to the cam and the weight of the van the 1900 stall converter is stalling a little to high for my liking.. Stalling at 3000... and running through the gears too quick with the 3.33 gears... I am going to use a 1450 stall converter as it will easily stall past 2000-2300.... My 2.84 Bonneville with an old LN3 3800 stalls at 2000 Rpms... Just looking to make the van super drivable as it does get driven a lot...


Thats just the short Update for now...lol

[Duke George V]

Did you use higher ratio rocker arms, or did you feel the cam was enough?

[Jr's3800]

Still have the 1.6 stock rockers... The Valve Lift for the cam is .517 Intake and .498 Exhaust, so the cam is a bit lumpy... when you hot start it you know it has a cam...LOL... The cam is a Performance cam, it in my opinion is a little more than I would want in a street vehicle... But being that its a Comp Cam Extreme Energy cam it does have good useable torque like any other 3800 and the cam specs show the cam is good from 1000-5500 Rpms...

I have the van set up to do a 6100 Rpm shift, this is not really good for the trans pump... So I will change that to force the shift at 5900 or so with the 3.05 gear set... This should get me a 48-50 Mph 1-2 and a 90-93 Mph 2-3... As well around town and on the road I should see better MPG's... I am thinking 18-19 city and 25-27 Hwy...


Like I have said in the past... This van has become so practical it not even funny now... Love the extra room... Love the fact that I can tow... Go get a fridge or a washer if needed.... Go pick up Lawn and garden junk... Just to user friendly... And the looks I get when people get near me trying to figure out where that deep exhaust note is coming from... LMAO.... I love seeing peoples Jaws hit the ground when I hit the button on the fob for the sliding door... They are always like WTF they had that back then?

Somewhere along the line I am going to repin the PCM connector and use a 98-99 PCM in it... The 98-99 PCM is quicker and better than the 97 PCM's I have used.. There are more N/A Tunes out there for the 98-99 PCM's and the Tuner I am using( DHP ).. Should be interesting..

[SCREECH]

I love seeing peoples Jaws hit the ground when I hit the button on the fob for the sliding door... They are always like WTF they had that back then?

YES...hahaha! I often find people are surprised when they learn about these vans from the '90s having the power door. Thankfully my new van has the AU0 remote keyless entry, so I'll have to snag a fob for it. I always thought it'd be a great feature for loading stuff when your arms are full. I carry a large toolbag for work, so just hitting the fob and not having to fumble with opening a door or trunk before setting the bag down really works for me.

Here's another thought I had, along the lines of power doors...how bout incorporating the power hatch system found on some late-model Chryslers like the Pacifica? I don't know if that's just done with special shocks and a release solenoid or what, but I want to look into that more. THAT would be useful...as long as you don't open it when there's an obstruction behind/above the hatch.

[Jr's3800]

That power rear hatch would be cool to do... I would love to see that...

For the Remote you want ABO0203T Lectron 10286022 Canada 218 101 229

I need to get a couple of new ones myself...

[Duke George V]

Hey, I wanted to ask you about the rocker arms. How long does it take to install them? I imagine it's pretty much a pain in the ass to do the rear bank.

[Jr's3800]

I can't remember what exactly was in the way to do the rear valve cover gasket... I know I was having a bad day as 2 of the bolts snapped off when I went to remove them.... Took me a little while to get the bolts out.. Good thing they were oil soaked too...

I did the rockers when I had the Lower intake off to do the gaskets... I did some port work on the lower intake while I was there... And installed the rockers before I put anything back on... The 1.8 rockers give you a lift of roughly .460, but this does not change the duration, just simply bumps the valves further open... And you have to install them properly, not hard to do really... Have to be really careful with the rear side as its hard to see whats going on back there...


On my little update... I am having a hard time telling what really wrong with the trans.. It almost feels as if the Torque converter may be the issue.. I did a lot of research into the Converters GM used... Its strange that 96-97 Converter seem to be particular to 96-97 as they use a Carbon Cluth... The van was updated to the 1997 Bonneville PCM with a 100% Bonneville tune... The older converters could not handle the odd TCC Lock strategy... So we might have cooked the converter clutch...

But thats ok... I have swapped out the diff in my SRTA trans to a 3.06 as opposed to the 3.33 I currently have.. and the Torque converter with the SRTA trans is a Carbon Clutch converter... So this will function with the 97 Tune as well as the 98 Bonneville tune as the van will be upgraded to a 98 PCM.. Lesson learned I guess.....

[Duke George V]

One more question about the rockers. I know they will provide more power and therefore better performance. What about fuel economy? Better, worse, unchanged?

[Jr's3800]

The rockers did no worse for fuel... I was still pulling 28 Mpg on the road...

[SexySilhouette]

YES...hahaha! I often find people are surprised when they learn about these vans from the '90s having the power door. Thankfully my new van has the AU0 remote keyless entry, so I'll have to snag a fob for it. I always thought it'd be a great feature for loading stuff when your arms are full. I carry a large toolbag for work, so just hitting the fob and not having to fumble with opening a door or trunk before setting the bag down really works for me.

Here's another thought I had, along the lines of power doors...how bout incorporating the power hatch system found on some late-model Chryslers like the Pacifica? I don't know if that's just done with special shocks and a release solenoid or what, but I want to look into that more. THAT would be useful...as long as you don't open it when there's an obstruction behind/above the hatch.

I've been thinking about this. My 2001 Grand Caravan had it.

I've also been looking at power side window openers from a Mercury Villager...

[Jr's3800]

Time for a small update...

Got the trans out... Yanked the torque converter and believe that it was the stator/bearing in the Torque Converter that failed... When we went to dump the fluid out of the Converter we got metal bits... I am pretty sure this has been pushed into the trans so no matter what the case it will have to be rebuilt...

But I have the SRTA Trans attached to the engine and everything set back down on the Sub Frame with a new front Trans mount as well... The Comp Cam Lifters went in, along with the aluminum lower intake gaskets and Ported front and rear manifolds... While we had it all apart we decided to replace the master cylinder too, what a massive PITA... Slowly coming back together...

[Duke George V]

Gonna bring this back with another question. What sort of rewiring did you have to do, if any?

[Jr's3800]

Thats an interesting question... and that will depend on what you want to do.. at one point we had the new motor running on the stock PCM... But we used an L36 EPROM with the VATS( security ) Codes and Flags turned of so the PCM would not look for the security pulse..( The EPROM was a 1995 Bonneville EPROM)... To do this we extended the EGR wires due to the location of the EGR on the new Motor, made some length changes to the MAF, IAT, TPS and IAC wires to get them where we wanted... Then we had to add to a wire for the 2nd knock sensor... On this PCM its simple, you simply splice into the existing wire.. The PCM looks for a different voltage value due to having 2 sensors on the same circuit...

I actually ran a couple thousand miles this way... With no issues... Fired right up every time...

Later My Buddy installed the 97 PCM... The 97 Connector had to be wired into the the 95 harness... He had to add the Map circuit wiring, and had to go to a 2 channel knock sensor set up...

If this van had the battery on the passenger side, I could have easily set this up like a Bonneville with the PCM under the hood and the wiring harness to match...

On my 95 Bonneville( I seem to get side tracked a lot ) I am still planning on the 98/99 PCM and Harness... I got a chunk of the harness for the inside as well.. so I should be able to splice in for everything I need for the inside of the car... The 98/99 PCM is better in terms of tuning as opposed to the 97 PCM.. The van will stay a 97 PCM..

It just depends on what you really want to do...

[Duke George V]

That was a lot simpler than I was expecting. I also didn't know that the L36 was available in '95. Thanks.

[Jr's3800]

Yeah the L36 was used in the Pontiac Bonneville, Olds 88/98, and Buick Park avenue for the 95 Model year... The W Bodies did not see them until 97...

My 95 Bonneville is actually a 94 Production... Built 12/14/94 and delivered 12/21/94 iirc...

so it will all just depend on what you would like... There are things you have to do to swap to a Series II/III... The PS pump is in a different location, in my case I used the 97 GP Power steering lines... I adapted to the 00+ Bonneville alternator and tensioner.. Had to use a W body oil filter adapter... also used a GP passenger front mount( currently running a poly W body mount 1 inch shorter )...

The front motor mount bracket bolts directly to the block, the ac compressor bracket you have will fit, but you will have to shave a bit off to clear the dip stick tube...

You will be able to use your original trans 100%...

There is an ear on the newer motor thats not there on the older motor that had to be ground off to accept the trans Brackets...

A lot will work with most all of the parts you already have... The downpipe will have to be dealt with as they are larger for the series II... and a few other things that will seem to nickle and dime you to death...LMAO


also forgot I had issues with the Throttle cable hitting the master cylinder... at first I cut the Throttle cable bracket down a hair and ground a little off the end of the master cylinder... Later I added a small throttle body spacer, and that poly front mount to keep the motor from jerking back... So far so good... It was all and still is a learning process...lol