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defrag010

3.4L L28 stroker

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Generally a submerged arc welding process with wire feed on a special crank welding machine will be used.

 

The VW's I was talking about were Type 1 engines primarily, don't know what the Type 4 engines are doing, I know they are up above 2.8L now, from an engine that originally was 1700cc's I believe.

 

Spray Welding or Metallizing is not my favorite way to restore journals. Many people do it, but I prefer traditional submerged arc welding as it's a permanent adhesion, and can be offset ground as it's structurally similar to the parent metals. As was mentioned above, you can make cheeks, radius it, even lengthen it. You don't want to try that with spray-metallizing. In High Pressure Compressor Cylinders, Spray Metallizing will actually be forced off the parent metal and flake off in biug chunks trashing the cylinder and piston! Below aroudn 1100psi it's o.k., but above that you want a real liner...but I digress.

 

Monzster does raise another interesting alternative, it would not be the first time someone used a dissimilar rod with a smaller journal diameter simply offest grind an existing crank for stroke increase without any welding at all. I have some photos (old Film 5X7's) in an album of one of the cars I am referring to...in one shot when it was still OHC, it was a 3.3L, but in the later photos it has the OS Giken TC24B-1 head on it, on a new 3.5L block. This was at the paint shop, where the guy had all his work done. FRP doors, hood, hatch, fenders, G-Nose, Nissan Perspex Side and Rear Glass...superlightweight bodywork and over a million yen of Stereo in it to boot! And that was 1986...

 

There are lots of alternatives to approach the issue, it all depends on how the individual wants to go about it!

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Instead of welding the crank, how bout using a set of Toyota 3sgte rods and offset grind the crank to get 1.5mm more stroke (84.5). No welding and lighter weight. HMMM:D

 

Offset grinding doesn't mean no welding, unless the big ends of the rod are smaller than the L28 rod ends.

 

IF they're close in size, then offset grinding still might mean welding on the opposite side of the offset cut, right? I mean, you don't want an elliptical rod/crank journal, so welding on the opposite side to grind into round would be essential in most cases.

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This is rather interesting. Were any of you guys at the JCCS last month? If so, you might recall the blue Kenmerri Skyline in full factory race guise. I was able to have a limited conversation with the owner, he speaks far better English than my Japanese, and he explained to me that his car in fact had a 3.4 L series. I did not note any of the specs he mentioned as I did not think there would be a discussion about this subject, but he did say that the crank had been welded and re-balanced. Anyhow, he said it has been running this way for over 10 years. And if any of you heard this car as it came in or left, you'd agree it was unlike any other L series you've heard. The thing sounded like a pissed off small block Chevy. I have little reason to doubt his claims. And as mentioned earlier in this post, all of us at one time or another have been told something was impossible only to find a way to silence the doubters. My opinion is that we should all cheer our bretheren on. They may well fail in the end, but isn't it better to see someone make the attempt and find out for sure that something can't be done? If we all just gave up when someone said it couldn't be done we'd all still be sitting in a cave wearing loin cloths. Even if I had not seen a 3.4 motor in person I'd say go for it.

 

Brian

AMEN!

 

That's why I'm building an RB30DE and that's why NZEDER is too!

 

:D:biggrin:

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That's why the dissimilar Rods (Toyots 3SGTE), different journal diameter.

 

Same reason guys use 5.7" Chevy Rods (and recut the Journals) on Stroker VW Air Cooleds, and VW Type 4 Center Main Bearings on wleded strokers when used in Type 1's!

 

Problem was, you had to use the 'Good' Chevy rods, as some of them weren't forged in the early days! Kinda like cast cranks.

 

Man, thank Gawd I went with imports that come with all forged internals!

 

Or maybe that's the reason I went with them! LOL

 

I still remember my Fairlady Z with the hood open gathering all the looks back in Michigan: "Wow, Fuel Injection on a 1975?" ROMAFLOL

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hahahaha.

 

yeah apparently some dudes use chevy rods on RB30's too, but by the time you machine them to accept the proper bearing, cost runs up and it's not economical or beneficial in comparison to aftermarket RB rods.

 

So would the 3SGTE rods work in this application?

 

I say go for it!

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...and what happened???

 

Not sure if this topic is no longer the flavor of the decade, but I am in the process of a very similar build with a LD28 block. Block has been bored to 89mm. Min wall thickness of 3mm. Interesting to see the wall thicknesses are in the 3mm - 5mm range. So there is some shift in the core.

I have decided not to use the LD28 crank as it would also require welding, so have opted to use a L28 which is being welded and stroked. Currently set at 90mm. Using the forged 4g63 rod (149.86mm) with the 48mm big end. Small end has been rebushed to 21mm. Piston is a standard 89mm KA24E. Piston requires a 1.4mm skim to remove the slight dish. This gets it to a 0.01 positive deck height for use with a 1mm gasket.

Interesting to note that despite the increased displacement - 2.8 to 3.35 there is a weight saving of 257g per cylinder over the standard L28 piston and rod. Standard is 1355.6g. New rod/piston combo is 1098.6g

If anyone is interested in this build, let me know, and I will post as things happen.

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Les Collins Racing in Australia is producing L34's for some time. Think it's 90x90...

Make an order and wait for delivery!

 

In fact, search for videos of "The Green Monster"

Edited by Tony D

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Thanks Tony.

 

I am aware of that. They use a modified RB30 crank which involves the widening of all journals, and machining to snout and flywheel flange. Honda rods are used and special pistons with a low comp height to make the rod ratio acceptable. I don't live in Australia so having someone build one for me is not an option and besides that, where is the fun?

 

This is a slightly different approach, being based on the LD28 block. I have read plenty of thumb suck info regarding this block, probably because of the 'small' pistons it houses. There is a lot of presumption regarding wall thickness etc. I have also read suggestions about using liners. It is not necessary. I have the block sitting in the garage, machined to 89mm. The wall thickness is not less than 3mm at any point based on 12 measurements in each bore. I thought about going 89.5mm but decided that another rebore in my pocket was a safer bet.

 

My approach is to use as many "off the shelf" parts as possible. The only specialized work is the welding and offset grinding to the crank. I agree with a previous post of yours where you stated that a lot welded cranks if done correctly see years of service. The point is to find someone who specializes in crankshaft repairs, and not a run of the mill shop - pardon the pun.

 

Finding LD28 blocks in South Africa is not an issue. A contact has a fleet of Patrols which have been converted from petrol to diesel, and as they run out of rebores they become scrap.

 

There may be people in other countries which also had the diesel motor, so this build might be of interest to them.

 

I appreciate that this is a very old thread, but if anyone is interested, as I said, I will update the information.

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Thanks Tony.

 

I am aware of that. They use a modified RB30 crank which involves the widening of all journals, and machining to snout and flywheel flange. Honda rods are used and special pistons with a low comp height to make the rod ratio acceptable. 

 

I'm sorry but that is incorrect. Who has fed you this incorrect information?

The crankshaft in the Green Hornet L34 is a an 90mm stroke EN26 billet item made by a company in Australia.

The rods are not Honda - they are a custom ordered Carrillo's, and the pistons are custom raised crown forged units for 11:1 CR.

 

I'm curious: how are you able to weld & then offset grind a standard L28 crankshaft to get it to 90mm of stroke? 

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My apologies to all.

 

Having checked a pm which I received some years back, the convo I had was with Peter at PMC: "we off set grind the crank (RB30) to 89mm stroke thats why we run the 48mm pin , and there fine , have run them in 700hp turbo rbs for the last 5 years " and not LCR. I'm getting old and all Aussies look the same to me. ; ) Lurcher you are correct - that is an entirely different set up. And a price tag in a different time zone I might suggest.

 

My build is for those who can't afford that spec and/or like to do as much of the prep themselves.

 

I would like to put a question out there regarding a camshaft. As this is going to be as street car, and where I live is pretty hilly I require something which will give good performance but not require riding the clutch all the time. Any suggestions?

 

I'm hoping for something in the 300hp range. But street-able. My thinking is that with the extra cc I can tone the cam down. Possibly around the 290 degree mark? I will build my head around that - valves sizes and CR. Anyone with similar specs, that can report back? I do have a set of 45mm ITBs on my car so that should be sufficient. Pictures of which are in my gallery. You will see the LD28 on the stand too. I will update with some more pictures soon.

 

My car is about is about to undergo a complete tear down, so this engine will not be running for a while. I will however post as stuff happens. If anyone would like any specific info on the build, just let me know and I will be happy to reply.

 

Please remember that this is a low-budget build, using as many off the shelf parts as possible.

 

Thanks for any input, in advance.

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