In my engine I used 7/16" with standard threads along with the stock 11 mm.
The reason the main journal area cracked in my application (high boost and horsepower) was two fold.
1. The main journal area is very weak. The area between the cap surface area, and where it attaches to the block is thin. There are two large vent holes cast into the area which takes away material. The large bore undercuts the area as well and the radius is not that supporting.
2. The four bolt conversion - machining and installing a second main cap stud - weakened the area. The crack started from the drilled hole.
The block could be modified best for street use with a one piece crank support including the main caps - all in one.
I think I'm just going to have a girdle made if it is somewhat reasonable
It'll replace my factory aluminum piece as well
Those 'Girdle' pictures that would replace your Main Caps - and - would attach itself
to the Oil Pan Rail as well - is the way to go if you're planning above say 800HP :Eyecrazy:
- or - 1,400 HP Blown - at 'Insane' RPM levels -
but you're past a 'street car' status at that point.
Of course, should PC Engineer a solution that retains the stock 2 UZ Oil System -
at which point, he'll sell more than a couple of 'Crank Bras' -
a 2 bolt mains incorporated Girdle all round the pan rail - everything ARP - and - 'Fit' - with stock oiling somehow would be :
"A Thing of Beauty, Bevis..."........
definitely the 'Uzzie 2 Bling' item -
But ~~! as to a Girdles' manufacturing 'techniques' and materials - since the Girdle would be for the 'Alloy' 2 UZ FE Race Block and made of similar 'Alloy' material - it would not have the same coefficients as the stock Cast Iron 'Uzzie 2' block -
so my guess is anyone pushing a Cast Iron 'Uzzie 2' - hoping for a full 'Cross Your Heart' Girdle would be S.O.O.L :684: :censored:
Excerpt from www.Bulltear.com forum for AMC: http://tinyurl.com/235p7a
"Well they may have a couple of issues."
"One is that the expansion rate MUST be the same as the stock cap -
so if the Cast Iron caps are replaced with an all ALLoY Girdle encompassing Main Caps as well - would it then matter if the Block were of Cast Iron ?
I believe it might - :madfawk:
1045 is the popular choice of material and it has a co-efficient of thermal expansion that is VERY close to the stock caps and block, 212 - 750 deg F. is 5.9-7.5 (per pro grams specs) Which is probably heat treated.
When you use a plasma or lasered piece and it expands much greater than those numbers (mild steel) then your nuts will loosen.
Material stability is another one...mild steel will dance under the heat due to the stresses (unless stress relieved) and for that length and thickness of material if it is indeed mild steel it can cause bearing issues.
All this considering the machinist must do his math on the material involved.
Other considerations would be the flatness of the material.
Blanchard grinding give materials a ultra flat surface, better than just a machined surface.
The holes should also be VERY close to .500. Hopefully all this is integrated into this item."
Would it not be possible to create the girdle out of cast iron just like the block so that everything is kept the same so as to avoid the problems mentioned?
I'm also wondering if the stock mains configuration of the 2UZ with an iron crank girdle would be as strong if not stronger than the stock configuration of a 1UZ with it's own crank girdle? Maybe that could have held the 1200bhp you have on it's own?
Interesting, a quick "trd girdle" google came up this artical which I think I have read before:TRD made a girdle for the engine used in the Drag Racing Turbonetics - 2 Uz FE - Turbonetics is now running a V6 - faster than the V8 - .
Anyone check with TRD about the configuration ?
Thanks for the article on the Turbonetics car guys.
I rang Robert Fulco from Fulco Race Engines and had a good old chat. He bailed out of the Turbonetics deal because of supposed legal problems, but last year ran the old car with another team in Comp in the US. They ran 6.80's @ 207mph in a 2,800lb car with a 3 speed lenco and clutch consistently in BB/ALT. They reckon the engine is making 1,800hp!
The block was supplied by TRD, and came with 4 bolt mains (with the outer bolts splayed into the side of the block) and a girdle.
I asked him whether the engine would hold with the two bolt with a girdle and he was not sure, but was confident based on the fact they have had no difficulties so far.
I was put on to Larry Slutter from TRD, and spoke at length with him on the project. He said the 4 bolt conversion was substantial in terms of machining, and new caps were made. He tried looking for some extra caps they may have had but no luck - they moved premises and they got lost. I am trying to pry out of him some drawings for the mods and girdle but he is just ignoring me at this stage.
The stroker crank they used was manufactured by Sonny Bryant and is 3.750 stroke - with a standard 3.7 bore gives around 326 cubes. I rang Sonny and he said he could not sell one unless TRD gave permission or a purchase order - I am working on that too.
So for now we purchased a new 2UZFE block - grouted it, and it is now going in for o-ring groves and main bearing tang mods (2UZFE main bearings have the tangs opposite to 1UZFE - I prefer to use King Bearings and they only have 1UZFE). We will then get a CNC girdle made up to fit across the mains and sump rail.
I have a second block, and we will build a 329 stroker motor over time - the rod design is quite unique to get clearance TRD told me.
If any of you guys have TRD contacts or clout I would appreciate some help to get these things out of them.