Chevy 3.8 series II buildup

[kidhavoc]

ok guys here we go, time to cut loose with all those tips and tricks we've all been daydreaming and benchracing about. Starting from a raw block with nothing to it...what would you do special if you were building it for the street<heavy street that is>? what's the one secret you know that everyone else forgets?

[ItalianStallion1]

Build the bottom. Everyone builds the top and leaves out the bottom end. So get everything you can forged, or even cryoed. This stuff will cost some big bucks though, you know. Building your engine up is going to be a custom project. I think you can use the series 1 3.8 for a reference though. I'm not sure though because I'm not a automotive engineer. You'd have to talk to people and companies to see who would be willing to work with you on this stuff.

The main thing you want is lighter and stronger materials in your engine. The lighter your engine parts are the more HP you'll make and the stronger your engine parts are the more power your engine will be able to take. The two coenside. The other area is the computer. You don't know how the computer will react to all of this. You'll definetly have to get some custom tuning done. You might have to send your computer somewhere for a few weeks or even your whole car. Hope this helps.

[Patrick Javert]

Titanium rods, notch the block for crank clearance when stroking, watch for collision between the piston skirt and the counterweights on the crank if stroking, alluminum is always better than iron, before you build up have a specific use for your car, keep the car user friendly, have a nice day!!! :D

[WickEdSix9838]

Titanium rods are NOT needed for this application, just get some good 4340 forged steel rods, crank, and forged pistons, that will be a very reliable short block, it will handle 150-200 shot of NOS no prob, and will be able to be turned lots of RPM's with no problems

[bluecmaro96]

aluminum is not always better than iron, lighter ye better nah. i would rather have iron heads that are strong than aluminum that is light. like stated above stronger connecting rods, crank, and forged pistons should be able 2 handle a 200 shot........ im hoping anyway hee hee only problem is the only place i can find aftermarket rods are custom from crowler, 700.00 custom crank ha you dont even wanna know how much :D

[Dominic]

One of the best things you can do aside from going with custom-built lightweight components and cryogenically treating everything is to simply blueprint your engine.

I would stick with the iron block/heads - theyre fine for our 6,000RPM redline. If you plan on raising the redline you'll need to do some serious transmission work - it is the redline determining factor for our cars since the 3800-II can easily take 6500RPM.

Custom alloy forged pistons, you're not going to do much better unless you have them ceramic coated... Which simply holds the combustion heat in better and insulates the piston head well from the heat [img]smile.gif[/img] .

Lightweight moly rods or aluminum/titanium alloy rods will be the best for your money - and shouldn't cost too much either. If you stroke it, be careful... Personally I'd leave the compression alone unless you shave the heads a bit.

Port/polish the heads, go with a nice valvetrain of course, find a cam which suits the engine's new performance characteristics and your driving style/launch style, etc etc... :D

[Mike Mayron]

<blockquote>quote:</font><hr>Originally posted by TheCardinal:
have them ceramic coated... Which simply holds the combustion heat in better and insulates the piston head well from the heat <hr></blockquote>

I know that some boost freaks ping like crazy w/ it and opt. to skip it on their high perf. build ups for forced induction.

Our crank may not be all that weak eaither, I can't remember ever reading of a failure due to it.

If i had a fresh engine, I'd blow mine up to see what breaks first! I don't think we really know the weak points of the 3.8 other than people shattering pistons. Never heard of a bent rod or anything so if I had two engines, I'd keep them in a constant rotation between my fenders untill i found all its gremlins. I bet I could get real good at doing overnight swaps like that ;)

[black98V6]

I realize that aluminum heads aren't available for our cars but I will pass along a little story..
got a bud with an 86 vette, it has the tuned port L98, except it was auctually built in late 85 and has cast iron heads. They didn't move over to the aluminum heads until 86. He has overheated that motor at least 2 or 3 times, had radiator problems and water pump go out. Anyway he has never had any kind of problem with the head gaskets leaking, heads warping or any other problems, and here is the best part.. he rolled over 200k a couple of months ago..... I know alot of people like aluminum stuff but man good ole cast iron and forged steel... that stuff is made to take a beating!.. anyway just thought I would pass that along..

[WickEdSix9838]

Titanium rods are not needed for this application, titanium rods are WAY more expensive than you guys think, im talkin thousands of dollars for a set,

Aluminum rods will work BUT they need to be replaced WAY earlier than steel rods do...
Proof being, my dads race car used to have a 427 big block with oliver steel rods, he ran them rods for 5 years(200-300 passes a year) turning the motor 8500 RPMS,the only problem he has was the bushing in the pin side tried walking out, but with that many passes they should!..the motor he has now is a 509 big block and he runs Groden aluminum rods which are top of the line aluminum rods, they have to be changed every 150-200 passes turning this motor 8400 RPM's
Just get a set of the Crower 4340 rods, they will be worth it, you wont break one unless you assemble the motor wrong,

And...aluminum heads are way better than iron, theorectically iron makes more horsepower but..the weight difference between iron and aluminum is worth more than the power your gonna gain with iron heads, also aluminum can be fixed a LOT easier than iron heads if you blow the motor or blow a head gasket, aluminum can be welded easier than iron can, welding on cast iron(spray welding) is new technology and is very expensive compared to having an aluminum head welded

[strobhen]

the direction I would take in your situation is forced induction. Build the motor for it. Even lower comression to 8:1. Take some hints from the GN guys & do some alcohol injection and up that boost.

[Dominic]

#1 I would never fix a head, welding aluminum is not a fun trick either

#2 -Cast iron will still make a more durable engine, even if it is heavier. black98V6 is absolutely correct.

If you're trying to win a champinship, fine go with aluminum. But I'll stick with iron heads - theyre much more dependable.

[WickEdSix9838]

hey cardinal, im not flaming, but apparently you havent been around performance cylinder heads long, my dad ports cylinder heads for a living and ive been workin for him for about 5 years, and i KNOW aluminum heads are better, i would MUCH rather have a lighter cylinder head that can be fixed if need be, than have to buy a whole new set of iron heads and have them re-ported and so on, your just spending double when you dont have to!

[Pro Stock John]

Well, I have would have to say that I would either turbocharge or supercharge a stock motor.

I think that the 3.8 A4 setup will run mid 14's with bolt'ons and a mild racing setup. So let's say 14.5. I'd look at running 8-12 lbs of boost. People blow up their motors because they don't typically run the right tune and fuel system. The 3.8's don' seem to run that much timing advance stock, so I think that 8 lbs of boost would work okay.

Otherwise I would do heads and cam. Might need to go with bigger injectors depending on what the stock injectors are doing at max rpm.

I think a heads/cam/a4/3.8 car with extreme weight reduction can run 12.9's.