Another 3800 build thread 2017

[Imp558]

I'm starting to get a bit more serious about next year's engine. I think I have a solid plan, but I'm really looking for criticism and advise just in case I can make some improvements before the coins start tumbling into my engine bay. I'd like to shoot for a realistic 350 WHP and before anybody asks I'm not open to a turbo, or an LS swap. If I land around 330 I'm good with that but 350WHP / 400 (ish) TQ is the target.

 

At first I was looking to build a solid L36 bottom end but I keep reading on other forums that with a high compression bottom and a shit-ton af boost they tend to start knocking pretty quickly. I have a couple perfectly good L67s here so I'll shift gears and go with one of them.

 

There's a lot I want to read through, James did some pretty cool oil return and windage mods that I want to read up on before I send the block to my engine builder. Also I've ordered a couple books on home flow testing and porting and there's a pile of L36 heads here to practice on so I'll be having a machine shop oversize the valves and I'll be porting and gasket matching. I'll be rebuilding my GEN V, not the pos one I had at the gathering but my real one with the exception of front rotor bearings.

 

 

L67 Bottom end, fresh rebuild

Ported heads / larger valves

Double roller chain

CAM: XPZ? (want to use this cam but I can't find any info about the required machining of valve guides)

Springs / Rockers / lifters / TBD based on cam selection

Gen V -w- N* tb and a variety of ever decreasing pulley sizes

Intercooler

Larger Injectors - size TBD based on valvetrain

4T80

Nice used set of TOG headers and 2 1/2" pipe all the way back

 

If anybody has any links to our threads that would be useful I'd like to see them,

Also any thorough tuning guides we can post a link to?

Edited September 20, 2017 by Imp558

[Grandprix1]

What transmission are you thinking? There's no way our stock transmissions will hold 400lbs of torque. From everything I've read your probably gonna want an intercooler and do as many supporting mods as you can while the engine is out of the car. E85 and then some spray. Nitrous is probably what's going to get you to that goal after you've gone to as small of a pulley as possible.

 

 

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[digitaloutsider]

Don't know why you'd be so against a turbo setup, because with even something like a lame Z3 setup and cheap intercooler, you're at 350 WHP without cracking the engine open. Turbo setup would be cheapest way to go rather than spending money on head work to support an aggressive cam. I'd make a turbo work long before I fucked around with machining heads, installing leaky intercoolers, etc. This has been proven time and time again in the 3800 community.

 

Now that all of the common sense is out of the way..

 

IMHO, I'm bet you'd be able to squeeze ~340 or so with just an Gen V, XP cam, E85, and the right amount of timing. Other than that, I'd do an XP cam, Gen V, FSIC, and LQ4/N* MAF and TB.  Unless you're running E85, the biggest injector you will possibly need is 42#. Move to 60# injectors if you go with corn. I think 350 WHP would be realistically attainable there.

[Imp558]

IMHO, I'm bet you'd be able to squeeze ~340 or so with just an Gen V, XP cam, E85, and the right amount of timing. Other than that, I'd do an XP cam, Gen V, FSIC, and LQ4/N* MAF and TB. Unless you're running E85, the biggest injector you will possibly need is 42#. Move to 60# injectors if you go with corn. I think 350 WHP would be realistically attainable there.

I was looking at the XP too,, I'll post a link to the cam comparison I was looking at tonight. The biggest reason I don't want a turbo is that they tend to make power high up and I want some more low - mid power since I actually want to drive it. I'm not in it for the numbers game.

[Imp558]

What transmission are you thinking? There's no way our stock transmissions will hold 400lbs of torque. From everything I've read your probably gonna want an intercooler and do as many supporting mods as you can while the engine is out of the car. E85 and then some spray. Nitrous is probably what's going to get you to that goal after you've gone to as small of a pulley as possible.

 

 

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Intercooler and 4T80 are on the list. Also I got some digital temp controllers to run the pump and also a small fan or 2 on the heat exchanger. My pump will only run when the coolant gets warm and the fans will only run when the hot water hits the heat exchanger, reducing parasitic loss. That equates to an ACTUAL cooling system for my IC. Edited September 20, 2017 by Imp558

[digitaloutsider]

That doesn't make sense to me. Why would you not want to run the pump at all times? You need to ensure that the coolant temperature is as low as possible at all times. In fact, the ONLY switch I would bother building into an IC system is a flow-detect switch, so if the pump dies/quits working, you get an indicator lamp. 

 

The only control I've seen people add is a TPS PWM controller so the pump speed is slower at no/low throttle, and full blast at WOT. Supposedly this is the most efficient cooling method. There was a thread on GPF about it years ago, but I'm having trouble finding it now.

[Psych0matt]

I was looking at the XP too,, I'll post a link to the cam comparison I was looking at tonight. The biggest reason I don't want a turbo is that they tend to make power high up and I want some more low - mid power since I actually want to drive it. I'm not in it for the numbers game.

twin charge

[Grandprix1]

Intercooler and 4T80 are on the list. Also I got some digital temp controllers to run the pump and also a small fan or 2 on the heat exchanger. My pump will only run when the coolant gets warm and the fans will only run when the hot water hits the heat exchanger, reducing parasitic loss. That equates to an ACTUAL cooling system for my IC.

Ah ok must have missed those. Was just my thoughts on it. Shaun probably knows just about everything to make these go fast. Turbo would do it especially since you don't have to open everything up and risk getting dust inside it. A smaller turbo should move the power band down a bit lower. You very easily go bigger and make more power if you wanted to as well. n20 isn't going to be what you want then if you want that power all the time

[Imp558]

That doesn't make sense to me. Why would you not want to run the pump at all times? You need to ensure that the coolant temperature is as low as possible at all times. In fact, the ONLY switch I would bother building into an IC system is a flow-detect switch, so if the pump dies/quits working, you get an indicator lamp.

 

The only control I've seen people add is a TPS PWM controller so the pump speed is slower at no/low throttle, and full blast at WOT. Supposedly this is the most efficient cooling method. There was a thread on GPF about it years ago, but I'm having trouble finding it now.

The same principle as a thermostat, that should give the coolant time to absorb heat before exchanging it. A proper cooling system isn't supposed to just circulate, while one side is getting warm the other is getting cool. Besides, since it's digitally programmable the temp can be whatever I want so it doesn't have to get HOT. When I'm on it the coolant will likely flow 100% on it's own.

[digitaloutsider]

Isn't the point of a thermostat to regulate temperature? Intercooler cores are small, and I'd have a hard time believing that you're going to be able to move fluid through it so fast that it doesn't efficiently transfer heat. I'm not a Ph.D in thermodynamics and I'm not trying to poo poo all over your idea, but it seems like it's completely unnecessary work that is going to provide you no-to-low benefit.

 

Reach out to Ed LaBarge (Sseilmnop). He's out in the middle of the state and builds phenolic intercoolers. He probably knows more about this stuff than most of us here will. 

[Imp558]

Eh, who knows. I did meet Ed this summer, nice guy. Really the worst thing that can happen is the pump doesn't turn on until the engine warms up and then runs like everyone else's. But on the bright side I get a digital readout of the IC core and heat exchanger. Not to mention when people look under the hood they'll see more stuff that's beyond their comprehension. I already have the whole system here and it was about $35 after the black acrylic to make the faceplate. I may get a digital temp gauge to mount inside the vehicle so I can see anything I'd consider overtemp.

[Imp558]

Pretty old thread but it looks like an //xp cam would get it done. Intense Stage 3 cam would be about right too.

 

http://www.clubgp.com/newforum/tm.asp?m=1550443&p=&mpage=1&tmode=1&smode=1&key=&language=

[Imp558]

This is DAMN interesting! My first head porting book came today. Everything I thought I knew was wrong, flow isn't everything if it compromises velocity. I can't wait to finish this book and read the Alex Walordy book when it arrives.

 

 

Edited September 22, 2017 by Imp558

[Psych0matt]

This is DAMN interesting! My first head porting book came today. Everything I thought I knew was wrong, flow isn't everything if it compromises velocity. I can't wait to finish this book and read the Alex Walker book when it arrives.

 

You spelled his name wrong originally

[Imp558]

You spelled his name wrong originally

Yes! Yes I did...

[Imp558]

There were known issues with 3800 heads from mid 1998 back, we all know this. Were the blocks all the same? Is there a reason why my 1997 block would be a bad candidate? How about my 1996 L36 block with an L67 crank and all? To the best of my knowledge they are all apples but if there's an orange somewhere I'd like to know before I get balls deep in this.

 

BTW, I'm on chapter 7 of my head porting book already.

Edited September 26, 2017 by Imp558

[digitaloutsider]

Blocks are all the same, minus minor casting differences throughout the years (primarily impacting the "Series III" blocks, which had different materials for stuff like the timing cover). There are no major differences like the heads.

 

There are no differences between an L36 and L67 crank. Do not remove a crank or disassemble the bottom end unless you want to go take it to a machine shop and waste a lot of money getting it bore-aligned. 

[Imp558]

Blocks are all the same, minus minor casting differences throughout the years (primarily impacting the "Series III" blocks, which had different materials for stuff like the timing cover). There are no major differences like the heads.

 

There are no differences between an L36 and L67 crank. Do not remove a crank or disassemble the bottom end unless you want to go take it to a machine shop and waste a lot of money getting it bore-aligned.

Cool, in this case it's going to need bore aligned anyway, my builder is doing the bottom end. I should have 3 usable blocks here. 4 if I count the L36 from the Monte but with 3 blocks that chose not to seize I can't see the one that did as a viable candidate.

[digitaloutsider]

IMHO, unless you just really really like spending money on machine work, I'd get the lowest mile L36/L67 bottom end I could find and go with that. Granted you have a lot of them sitting around, but the cost of shop labor is going to add up rapidly.

[Imp558]

IMHO, unless you just really really like spending money on machine work, I'd get the lowest mile L36/L67 bottom end I could find and go with that. Granted you have a lot of them sitting around, but the cost of shop labor is going to add up rapidly.

That's a good point, my engine builder is a friend of mine so I'm hoping he's not going to whack me really hard but I should probably go over everything with him before I start making plans written in anything but pencil. the stock l36 bottom end that came out of my Regal to begin with only has 80,000 miles on it and I have an l67 here out of a Park Avenue Ultra that has around the same. The l67 that's in my Regal I know for a fact was downright tortured for The Last 5 Years of its life.