Fallen2603

I'm looking to do a 3.4L engine, with a top-end from a 3400, and a forged crank from a 3500. I plan on doing a remote-mount turbocharger to boost this engine to under 10psi. I have a few questions, though...

1) Are the stock 3.4L V6 connecting rods forged? I have been told that the connecting rods out of the 2.8L/3.1L V6's are forged from the factory and was wondering if this carried over to the 3.4L V6?

2) If the 3.4L connecting rods ARE forged, will the stock 3.4L connecting rods work on the 3500 crankshaft? I'm having the rod pins on the 3500 crank ground down to 2.00" or a "small journal" size. I know that I can use forged SBC rods, as long as they are narrowed to fit in the narrower rod journals of the 3500 crank, but I was just wondering if the 3.4L connecting rods had a journal of 2.00" and were narrow enough to fit on the 3500 rod pins?

3) Will the 3.4L DIS sensor work with the DIS reluctor wheel on the 3500 crankshaft?

4) If the 3.4L DIS sensor WILL NOT work with the DIS reluctor wheel on the 3500 crankshaft, can I swap a 3500 DIS sensor into the 3.4L V6 without modification?

Any help would be greatly appreciated! And if I am wrong in anything I'm already taking as fact, please, CORRECT ME!

Six_Shooter

iTrader: (2)

Yes, they are a pretty stout rod, but I will be going with a small journal SBC rod in my 3400 for my Jimmy, just because they will be stronger.

Why would you do that? Part of what makes the 3500 crank so good is the large rod pin diameter.

No....

No.

The 3500 uses what they refer to as a "56x reluctor wheel". It is actually made up of two reluctor wheels, with offset notches. It's an odd one, and will only work with the 3500 PCM.

If you insist on using a 3500 crank, you will need to either use an external crank trigger, or have a crank trigger ring made to be installed in place of the 3500 reluctor wheel, that matches what the 3400 reluctor wheel looks like and indexed correctly.

I would just use the 3400 crank, and solve a lot of headache that you will be putting yourself through.

Fallen2603

How much power would you say the stock forged 3.4L connecting rods could handle? What kind of RPM's? Any idea?

Whether I go with the 3.4L connecting rods or swap in a set of modified SBC rods, I still need the rod pins to be 2.00".

What if I'm going with a standalone ECM that I have tuned to read the signal coming from the 3500 DIS sensor? Would that work?

Any idea where I could get a crank trigger ring that I could throw on the 3500 crank to make it similar to the 3.4L reluctor wheel?

I know that I could run the 3.4L crank, but I want forged internals if I'm running boost. Just my OCD showing through.
Besides, I'm getting this crank, with the rod pins ground down to 2.00", for only $390.

Six_Shooter

iTrader: (2)

It has been said that they are good for 7000 RPM, and people has used them to over 350 HP in turbo applications.

To use on the 3400 crank, yes.

I don't know of an aftermarket EMS that can read and then use that reluctor wheel of the 3500. The OEM PCM, has the crank sensor connected directly to the PCM, which then triggers each coil. This differs from the earlier 660 DIS that had the crank trigger connect to the ICM, and then used some inputs from the ECM to simply control timing, where the ICM was used to trigger each coil.
The term "standalone" is really a misnomer, for all intents and purposes the the OEM ECM that would be used here could also be called a "standalone", since it is a seperate system from the rest of the car. I have a Delco ECM installed in my Datsun, and installed it in much the same way a "standalone" would be installed. You're best off forgetting that term and using "EMS" (Engine Managment System), or "ECM" (Engine Control Module) or "PCM" (Powertrain Control Module).

The only ones I have seen sor far are custom. if you look around or ask at 60degreev6.com, someone there should be able to point you in the right direction. WOT performance has crank trigger kits for the 3500, but are designed for FWD applications, where the crank pulley is different than RWD set-up. Years ago, between my Grandather and I, we designed and built an external crank trigger for the "Franken60", that used DIS, in a RWD application. I have since moved that trigger wheel over to my Datsun, with a new sensor mount.

Money better spent elsewhere.

Is this a street engine? If you just answered yes, get off the "Forged internals" kick. Hypereutectic pistons work very well in force fed applications, I abused a set for over 2 years and they looked almost new when they came out of the block, I sold them to someone else that AFAIK is still running them to this day. Forged pistons require larger piston to bore clearance, that will cause more wear at start up, and also usually use more oil, as being burned at start up until the pistons are up to temp.
I also sugest you stop reading all the hype and mis-information about "what an engine needs", most crap floating around the interweebz is just that, crap. In an all out race build, yes forged would likely be the best choice, but that is a purpose built engine with frequent teardowns and inspections. If you don't plan to tear the engine down very often to inspect it, and don't like having a lot of blow by at start, or even piston slap, then again forged is not the way to go.
A street engine that will be moderate power levels will be fine, which your hybrid 10 PSIG boost engine will fall into the category of, will be better off with hypereutectic pistons than forged.

More information to chew on, in my Datsun is a 28 or 29 year old engine, I can narrow the engine year down to '81 or '82 from casting numbers, stock and un-opened as far as I can tell, I did just replace the timing chain a few months ago, but from what I see through the spark plug holes and with the oil pand and cam covers off, it's all stock. I've ran it non-intercooled up to 14 PSIG, I backed it down to 10 PSIG until I can get the intercooler finished, just need to weld the tanks on. The pistons are not forged, most likely hypereutectic. I plan to run upwards of 15 to 18 PSIG on this engine, and I'm hoping I can get away with not opening it up. The only thing that has me a bit worried is the ring end gap, since power adder engines usually need a wider ring gap than N/A engines do. I'm not worried about the pistons themselves though, since I know they will be fine, barring any lean or detonation conditions.

So if these and other engines with hypereutectic pistons can survive and drive well, so can yours, and be better off doing so than with forged pistons.

The stock 3400 cranks have been used to power levels over 350 HP, and should be good to much higher, so like I said before that money would be best spent elsewhere, than on the crank. I would do some prep to the crank, like polishing the journals, and adding oil lead in grooves if it doesn't already have them. I had to add them to my 3.1 crank for the Franken60, but most 3400 cranks I've pulled already had them.

Fallen2603

This engine will probably be knocking on the door of 500HP, but probably won't see 7,000RPM that much, if at all. I've heard that the power limits of these rods is based more on RPM's instead of horsepower. Is that true?

I was just using the term that most people are familiar with for ease of communication. I've heard those damn things called so many different names...it's RIDICULOUS. Why everyone can't call them just one thing, is beyond me. Like a carburetor. Who calls a carb anything else but a carb or carburetor?! Ugh...anyways. I'll look into 60degreeV6 to see if I can find a crank trigger ring for the 3500 crank. If I can't do that, I'll just go external DIS...

I've heard the arguments go both ways for a long time, too. Each way has it's ups and downs. I totally agree that the cast/non-forged components that I could use would be, if not better than, good enough for what I'm wanting to build. The money has already been spent on the crank and the work being done to it. Don't regret it. Would still do it the same way if I had a redo. I've seen numerous engines built with all-forged components used for street use that didn't suffer any problems as long as the operator followed basic maintenance protocals. If all these forged components were going to cost me an arm and a leg, I'd go with the cast/hypereutectic stuff without hesitation. However, I'm just finding good stuff at a good price, and I may as well take advantage of some better gear. Just the way I'm going with the build. not saying it's "THEE RIGHT WAY" or that your way is "THEE WRONG WAY". Both ways WORK, and that's all that matters...

bl85c

iTrader: (2)

The advantage of forgings is that they're tolerant of abusive conditions without snapping. They flex and deform before coming apart, whereas castings will hold to the breaking point and break with much less flex. From what I understand the achilies of these motors is often times the block- they split under detonation. No amount of forged stuff will help that. Keep it out of detonation and you're good.

Fallen2603

Keep it out of detonation...that's the plan!

Fallen2603

Oh, on the trail of a press on reluctor wheel conversion that will make the reluctor wheel on the 3500 crank like that on on the 3.4L crank. Hopefully, good comes of it...

Maverick H1L

iTrader: (8)

Check out the 60* V6.com store... They have a 7x reluctor wheel kit available. It's $170 or somewhere near there.

firstfirebird

iTrader: (3)

You don't have to re-machine the 3500 DIS wheel, only the crank itself. The ring is pressed on the 3500 crank, so warm the crank up, knock the ring off and tke it to a quality machinist and they will be able to cut the grooves in it to match the "981" nodular iron crank's DIS configuration. The "hub" that the ring is pressed on to is exactly the same size as the early cranks.

IF you are concerned about leaving the rod pin diameter, then there are fairly reasonable SBC rods that are available in 2.1" (maybe 2.2"?), so either the rods or the crank can be machined to accept the difference.

The trigger wheel from WOT-TECH (made by TCE) is not intended for the RWD setup. If you get rid of the smog pump and retain the 2.8/3.1 accy brackets, then you can make an extension for the wheel as well as the sensor mount. If you are using the 3.4 accy brackets, then you will have to machine the face of the alt/AC bracket to make it square and use a smaller extension on the sensor bracket, same size on the wheel itself.

If you are looking for 500hp, I would highly suggest using a 3400 block. We have in the works a modified 3400 oil pan to accommodate the f-body k-member, but that project is a few months away (being optimistic). The main caps with the measly two bolts WILL stretch, already been proven at mid-400hp and 475tq.

-John

Fallen2603

DAMN...well, that just made that a WHOLE LOT EASIER! The shop that I have the crank at right now, should be able to do that! HELL YEEEAAH! THANKS FIRSTFIREBIRD!

I'm not worried about the rod-pin diameter. The crank is already having the rod-pins machined to 2.00". Before I acquired the crank, the shop had already ground the rod-pins down to 2.060", so the next logical step down seemed to be 2.00". I'll either reuse the stock 3.4L rods, provided they're forged, or just bet a set of forged SBC rods that have been narrowed to fit.

Yeah, TCE/WOT-Tech informed me that their external DIS kit would not work for a RWD 3.4L V6. Hmmm...I don't plan on retaining the smog pump, and I would like to retain the 3.4 accessory drive. Maybe, if the modification of the 3500 hub doesn't work, I'll just modify the ALT/AC bracket and rig up some spacers for the external DIS to work...we'll see.

Huh? I was under the impression that the 3.4L had four-bolt mains...? Two from the top and two from the sides...? Did I get bad info? I'd be FINE with 400RWHP...

Six_Shooter

iTrader: (2)

RWD 3.4 is 2 bolt main, 3400 has the crossbolted mains.

I still don't understand taking away half of what makes the 3500 crank good....

Which 3500 crank are you getting anyway? There is a forged and a cast version.

Fallen2603

DAMN...is there anyway to convert the 3.4L to four-bolt main? Swap the 3400 main caps on there after drilling the cross-bolt holes?

UGH...okay, Six_Shooter, this is why I am having the rod-pins ground down to 2.00": I found out about this crank from Purple82TA when I went to take him some accessory drive stuff from my 2.8L for his 3500 swap. He told me about having this crank's rod-pins freshened up and machined down 0.010". That way, he could still get 0.010" under bearings, and still be golden. There was a mix up with the shop, and they ground the rod-pins all the way down to 2.060". Purple82TA and the shop were unable to find bearings to fit that undersize. He never went to pay for or pick up the crank because he couldn't use it...

Fast forward two years, and I enter the picture. I give Purple82TA the accessory drive parts he wanted, and I told him I'd take this crank as payment. He said fine. I went to the shop, and they still had the crank. Now, I already knew at this time that I could have the rod-pins ground down to 2.00" and use small-journal rods. It seemed like a logical step, considering the rod-pins had already been ground down to 2.060".

It is the forged 3500 crankshaft.

Six_Shooter

iTrader: (2)

No, the 3400 crossbolts are throughthe oil pan, before you ask, no you can't use a 3400 oil pan on a gen1 block. The bolt pattern is quite different, and IIRC where you would need to drill the block for the 3400 oil pan would cause some strutrula issues, meaning the oil pan rail would be narrow at that point, and I think there was some interferance with some other part as well. I didn't look into the details much when I saw the pattern was off and decided it would be less work to just use a 3400 block instead.

I know the story about that crank. Why do you think Dave didn't want it then?

Fallen2603

Okay, I'd heard there were a lot of issues with trying to do the 3400 oil pan on the 3.4L block. Guess that's not a route I can go. What about custom made 4-bolt mains? Anyone ever here of that being done?

LOL! I don't know what you're wanting me to say. It will be more than fine for what I want, and I got it at a good price. If I thought it wouldn't be strong enough, I would have stuck with the stock cast stuff which you and others have been telling me OVER AND OVER AGAIN will be more than capable of what I'm doing. I'm not worried. Sooo...WHAT-THE-F*$#-EVER.

firstfirebird

iTrader: (3)

It will still be stronger than the nodular iron, the 3500 crank is a steel unit, forged close to tolerance and machined to fit - actually a very high quality piece...

Here's one I sold to Six_Shooter lol...



and here's another I cleaned and shipped to bl85c...






and here's the differences in oil pans...

http://s158.photobucket.com/albums/t...%20oil%20pans/

Six_Shooter

iTrader: (2)

I still have that crank sitting in what is left of that crate.... It got a little messed up on the trip.

Even still, with the 3500 crank being stronger than the 3400 crank, that is definatly not the weak point here....

But people waste thier money on worse things I guess....

Fallen2603

firstfirebird
Ummm...now those are PURDY. I like SHINY things...
Anyways...
OH...will the 3.4L V6/T5 flywheel bolt up to that crank? Or will I have to hybridize something there, too?
Also, do you know of any way to make 4-bolt main-caps for the 3.4L?

Six_Shooter
LOL! Man...we're in the HABIT of wasting our money, HERE! At least, that's what 95% of people in the world would tell us about this hobby/OBSESSION of ours. I don't expect anyone to understand or agree with the way I'm doing this. I think it makes sense in some ways, and, yeah, in other ways it's definitely not necessary. I'm fine with agreeing to disagree. "Live, and let live."

Six_Shooter

iTrader: (2)

You're flywheel will be fine, they haven't changed that bolt pattern since 1982. Just use a flywheel from an '87 and up, since it will be nuetral balance.

firstfirebird

iTrader: (3)

w00t!

QFTMFT

Thought I'd "dumb it up" for ya, Six :P

firstfirebird

iTrader: (3)

Thanx. As long as they are in stock, $100 plus shipping (took $60 in shipping to get to Six, he's in Canuk-land)

DeathStarr89

iTrader: (1)

The neat thing about the 3500 crank is that the marks for the 7x notches are already there, the machine shop just needs to cut where the dots are.

firstfirebird

iTrader: (3)

SHHH!

You can't give up EVERYTHING!

:P

Fallen2603

COOOOL. Oh, what are the differences between the V8 and V6 flywheel? I'm having troubly finding better flywheels for the V6...can I use a V8 flywheel, or not?

LOL! There are dots for where the notches need to be?! LMAO! That's AWESOME...

Six_Shooter

iTrader: (2)

What?