Gauging any interest? in 350 laser-cut exhaust flanges

[Gasoline]

Hi Jim,

Thanks for your input! Great to have a "learned" brain looking over this.

Is a concern the strength of the remaining caps after the decking to block height?

If I remember the height of the caps is slightly lower than the rail and brass shims are used to preload the girdle. Hone the mains after fitting? I will source ARP studs to work with the block and girdle.

Yes thoses are oil drainback holes. I have seen these areas sloted on a V6 girdle.

I don't like the thin area of the girdle at the oil pickup. The cap is already cut and the girdle area is thin. If a tube could be press fit in a hole drilled in the girdle into the block, the pickup could simply be bolted to the girdle.

My MS Paint skills stink, but you may get the idea.

[Nothingface5384]

pm me when you get a price for the girlde, as by the time everything is thought out and quoted i may be back on my feet...hopefully

[Jim Blackwood]

Yes, longer studs for sure, recessing the holes would weaken the cross straps too much. Using the existing rear main studs is probably fine, and possibly
the front ones. If the girdle is clearanced for unmachined main caps and fitted with jack screws, then those can be lightly tightened and locked, (not torqued down heavy) which will support the cap without requiring the block to be align honed. I'm thinking add-on here, and 2 jack screws spaced more towards the studs would be better. If you wanted to mill the caps on a build in progress you could leave the girdle with no recesses and skip the jackscrews. I would prefer to use at least a 3/4" thick plate and 7/8 or 1" would be better. Sump clearance on some cars might be an issue though.

But the pickup is a problem that will need some creativity because of the angle. You could cut the angle on the plate to mount the tube, but we still have to seal the plate to the block. The best option for that is an o-ring face seal but that would be a complicated piece since it has to seal to the block and the pickup also, while not interfering with the attachment screws and provide a reliable alignment, yet not compromise the strap strength in that area. Getting it right the first time isn't going to be that easy and it requires two additional complex (because of the angle) setups on the plate and an extra part requiring at least 8 lathe operations. Then you have a problem if there is any variation in the height of the angle cut in the block relative to the pan rails, and there probably is some. The solution used by the V6 guys is obviously the easiest, and it is probably good enough, especially with the thicker plates. Putting the tube through as you drew has problems too. Getting angle and position exactly right, differences in the hole diameter, and sealing to name the obvious ones and it doesn't stop there.

[87GN@Tahoe]

while you're on the girdle track, you might as well think crank scraper also... or at very least, some type of milled slot and "o-ring" similar to TA's newest 455 girdles..

On my turbo6 my (i think it was drivers side) pan rail at the block would pratcally POUR oil due to the crank slinging it in that area... the girdle didn't have provisions (milled in slot) for an "o-ring" or any other form of gasket. The crank scraper provided by RJC prevented the oil from slinging into that reigon with full force, stopping the leak.

ALSO, on the RJC girdles, the main caps were milled (the idea of doing that doesn't bother me one bit, I would think jacks screws would provide uneven pressure on the cap, in turn uneven bearing wear...???...) The rear mains on the v6 also have a large space between the original bolt surface and the girdle (about 1/2" or more). RJC provided spacers which were welded to the main cap before machining flush.

Might as well think of all of these things now, before they have to be fixed later.

wes

[alan]

Originally Posted by Jim Blackwood

But the pickup is a problem that will need some creativity because of the angle. You could cut the angle on the plate to mount the tube, but we still have to seal the plate to the block. The best option for that is an o-ring face seal but that would be a complicated piece since it has to seal to the block and the pickup also, while not interfering with the attachment screws and provide a reliable alignment, yet not compromise the strap strength in that area. Getting it right the first time isn't going to be that easy and it requires two additional complex (because of the angle) setups on the plate and an extra part requiring at least 8 lathe operations. Then you have a problem if there is any variation in the height of the angle cut in the block relative to the pan rails, and there probably is some. The solution used by the V6 guys is obviously the easiest, and it is probably good enough, especially with the thicker plates. Putting the tube through as you drew has problems too. Getting angle and position exactly right, differences in the hole diameter, and sealing to name the obvious ones and it doesn't stop there.

How about block the whole works off and come out the side of the oil pan?

[sean Buick 76]

Originally Posted by 87GN@Tahoe

ALSO, on the RJC girdles, the main caps were milled (the idea of doing that doesn't bother me one bit, I would think jacks screws would provide uneven pressure on the cap, in turn uneven bearing wear...???...) The rear mains on the v6 also have a large space between the original bolt surface and the girdle (about 1/2" or more). RJC provided spacers which were welded to the main cap before machining flush.

Might as well think of all of these things now, before they have to be fixed later.

wes

I agree that milling the caps is the way to go then align hone once everything is torqued down.

[Jim Blackwood]

Originally Posted by sean Buick 76

I agree that milling the caps is the way to go then align hone once everything is torqued down.

That makes it a lot easier to make the girdle. But I'm not tearing my brand new, yet to be run engine back down for that so if I use one it'll be done the other way. As long as the jack screws are just snugged down there will be no distortion of the main caps and they will provide the same restraining force as a strap laying on the cap would, maybe more. Not a hard modification to make. I'm also not going to run an external line or a custom pan, though a scraper or at least provisions for the original windage tray would be nice. As far as using an o-ring, sure, if you can get someone to cut the groove for it. (An O-ring making kit was "only" about $70 the last time I checked, maybe closer to a hundred now, but happily I do happen to have one.) But I'll just glue it to the block with "Right Stuff" and there'll be no leaks there. Won't move either. Take a prybar to remove it, but that's OK. The spacers will require careful measuring and fitting and should probably stand a couple thousandths proud of the rails. There'll be that much flex in the plate and pre-tensioning it that way will actually help as long as the rail studs are tightened after the mains and then the jack screws snugged down. Probably locating them to bear on the lugs on top of the caps would be the best place. Better that than the other way around with the girdle having to be pulled down by the main studs. With a flat plate, yes, the entire block including caps and spacers should be milled as a unit to ensure flatness. Now just exactly how was it you were going to hold the caps in for that operation? If you just mill the caps independently there is no way you going to be able to make sure they are perfectly flush with the pan rails. So some sort of custom fastener maybe? Sounds expensive to me, and maybe not as effective. Since the straps are not pre-tensioned, in order to get any really significant strength from the girdle it really should be about 2" thick. Think of it this way, you are removing about a third of the height of the cap and replacing it with the strap. Overall the assembly is thicker but it is now laminated. Is a multi-leaf spring as rigid as a solid bar of the same thickness? Not even close, and 1018 is not anywhere near as rigid as cast iron. The real strength comes from tying the entire bottom end together, not by resisting downward force at the center of the cap.

And I think a stand-off for the pickup and the narrowed strap used in the V6 design would be just fine, and the easiest way to do it. Especially with 1" plate. (btw, the illustration "A" and "B" have the cutout for the pickup in the wrong place)

Jim

Edit: While you're at it, look into the cost of alloy steel plate as well as the 1018. I'd just as soon have 5/8" of Cor-Ten as 1" of 1018. The cost is probably comparable and it'll be cheaper to cut.
J

Here's an idea for you if you want to cut your caps. Cut 'em to size, assemble the bare block and install the girdle, and then sweat-braze the caps to the girdle in an inert gas oven. Then align bore your mains and you have the ultimate bottom end. One solid piece. If you want to get fancy, combine it with a dry sump. Some of those are around for the 215 in aluminum. It's a rare and expensive piece, but that's as good as it gets.
J

[Gasoline]

Originally Posted by alan

How about block the whole works off and come out the side of the oil pan?

Shoot yea Alan, that works for me. I like it. I do not want to get the first girdles too complicated. If we left the girdle metal over the "oil up" area, it could always be machined away later if anyone wanted to make a way for the "oil up" to work.

Thinking about oil?.....Have you guys seen this guys conversion to do away with our pump off the cam to a Gerotor oil pump? Looks simple if you had a mill, (which I do not). I have bought the pieces from a junkyard, just need to modify them. Wack off the lower half of a Gen II V6 and add it to the top half of my buick 350 timing cover, modify the pump/balancer.... Also it gives me options of where I want to put the oil filter. If I stick the turbo low on the passenger head, I can use the oil filter mount that pushes the small oil filter to the side of the block. I like the options. This may need its own thread.

http://www.turbomalibu.com/oilpump.htm

Jim, I do not know much about the metal candidates? 1018, 1026, 4140ANN, 4340ANN, Cor-Ten? May have to come back to this after getting a drawing and potential fabricator to cut the initial design out. There is a Mopar girdle on Ebay made out of 3/8's steel.

That was a good idea about cutting with a waterjet instead of a laser. I found this and will stop in sometime.

http://atlantawaterjet.com/index.html

Back to the exhaust flanges: After the flanges are shipped to me and I am sure they are worthy, I will collect funds and ship out. That is what I would like to do. Thanks to all.

T

[Justa350]

I'm not trying to pee out anyone's campfire, but how many guys have launched the mains out of a 350, or at least flexed the bottom enough to cause bearing wear issues thus requiring a girdle?

Again, not picking any fights like CASON does just truly curious. If there are such experiences I hope they come to the surface so we can collectively pursue a stronger combo, based on where failures have already occured.

I was thinking about making a stepped girdle that just uses jack screws to put preload on the main bolts. If this flat one is the better option, I might be inclined to save myself the hassle and just hop on this batch.

Bill, care to offer up any experiences here?

[Gasoline]

Mark, good point. It’s a welcomed open discussion. The girdle is not for everyone, and there are very few (any?) cases of crankshafts letting go at naturally aspirated horsepower levels and low boost levels. Even if I have them made there may only be 2 or 3 takers at a target price of $250.00?

I hope I can venture my 350 into Bills territory. My goals start at 18 pounds. The Buick V6 turbo guys pushing big air have already given us a historical warning. There are many members in "The Drive Over The Crank Club" on the turbo Buick V6 sites. Lots of pictures of scattered engines. This simple flat steel girdle idea seems to work fairly well for them. Maybe this design helps better with side to side cap walk? or who knows? Anyway, I am looking at their experience and solutions to problems they encountered.

If it was stock parts, I would not care. I am hanging big $$$ on a cast crankshaft. I would like to make sure it stays in the block....at least for a pass or two.

Thanks for your input.

[71skylark3504v]

If I remember correctly, I think Bill M. only used a mini girdle on his procharger build. It wasn't near as nice as the girdle shown in this thread. However, I may be wrong.

[67fitz]

OK back to the exhaust flanges what are the advantages?

[BillMah52]

Cason is correct. The halo we fabricated only tied the 2,3, and 4 caps together. The only issue we had was some evidence of twist above the 700 hp level. Some minor "scuffing" along the bearing edges on the 3 center mains. We didn't see the need for a full girdle until we were above 15# boost.
That is when the cracks in the webbing above the mains appeared.
In my opinion, either style girdle, flat or stepped will help with both situations if it is tied together with the pan rails.
I think Tom's thoughts are on the right track. There will only be a few who may need this piece and those will be high dollar builds. If there is a need for some extra machine work or modifications to the oil system then that will just be part of the build. We aren't talking "drivers" that will need a girdle.
One other note of interest. With a girdle, we will need a fabricated oil pan and pickup.

[Nothingface5384]

and theres a guy on this board that i'm sure wouldnt mind doing the pan/pickup

[Justa350]

Originally Posted by BillMah52

We aren't talking "drivers" that will need a girdle.

Whadd'ya mean Bill? I'm gonna drive mine on the street!

Oh, and I wouldn't mind doing pans and such either!

[gsjohnny1]

header flanges are needed for quite a few cars. girdles...only a handful will
want or need one. myself no. a thicker piston wall block for what i am doing, yes.
wish i had bigger machines in my garage so i could do what i really want to do

[Nothingface5384]

yea, mines also going to be a driver/track car

[Nothingface5384]

i was thinking Steve Reynolds more specificly but we all you you can make them too mark

[87GN@Tahoe]

The v6 caps are machined out of the block.... I suppose there might be even faster stock block ET's if they found a way to machine them in the block, or tried your brazing idea.

In the v6 kits, (if i remember correctly) there was shimstock provided, to allow for adjustment in obtaining the desred .005" preload.

I think an aluminum spacer like the RJC piece would be a simple fix.. OR perhaps a 3/4" shallower "Mark Burton" aluminum oilpan with kickouts, trap doors, and all the other okie-charmers.

For $250 I would DEFINATELY be in for one... prices before looked to be in the $400+ range (and I was still interested in one)... I was half-tempted to make one myself, but never got the transfer screws or the gumption to start(don't have CAD, or CNC.. it would have all been manual operations).

Dont forget to include surface-grinding the plate true in your estimates

[Jim Blackwood]

I might be interested in a blank but I'd want to do the machine work myself.

Jim

[Gasoline]

Originally Posted by Jim Blackwood

I might be interested in a blank but I'd want to do the machine work myself.

Jim

Steps I see needed:

1) Finish CAD drawing. Those that want to be in look it over to modify and accept as a tiny group.

2) Decide on steel material and thickness.

3) Jim, I liked your idea of having a waterjet do as much cutting out, oil slot, and bolt hole work as possible. I first had thought of having the machinest do all the bolt hole work, but now I think the waterjet way is accurate enough we should not have to leave the bolt holes fractionally smaller for a machinest in the next step to fine tune and adjust the bolt holes.

That is what I consider a "blank". From the waterjet ready for final machining.

4) Find machinest to countersink rail bolt holes, blanch grind flat? and hopefully no fine tuning to CAD drawing.

5) Source ARP fasteners.

6) I will TIG my own aluminum pan(s).

7) Your engine builder will assemble cut caps, oiling pickup/route?, and align hone.

In the laser flange buy there are 2 people making a profit at $58.50 each pair. Craig, the guy at the Header Company, and the Laser Company he uses. With girdles we will have the Waterjet company and the Machinest. I'm WAG guessing at the $250.00. Blank price cheaper (no Machinest cost). Maybe we all want "blanks" and find our own Machinest? or you engine builder is capable of machining and fitting. Yes materials will be much more, but overall it seems like a good target to the cost of the flanges we have put together.

[Jim Blackwood]

If I might make a couple of suggestions.

Cold rolled is going to be flat enough, without the need to blanchard grind it. You only need one side perfectly flat anyway and there's enough give in the material to take up any slight variations in surface flatness, which should be negligible for our purposes. If the caps are going to be machined separate from the block there's nothing to be gained by blanchard grinding the plate. Also that spec of .005" proud on the main stud spacers is going to negate any theroretical gain from grinding anyway. (I'd think .002-.003 would be more appropriate myself.) The surface variation in cold rolled is much less than that. The water jet will not induce warpage and any warpage induced by the counterbores or other machining will be practically undetectable.

Don't take the waterjet guy's specs of .003-.005" tolerance as gospel. More likely what you are going to see is .003-.005" of TAPER on thick parts, meaning the bottom of a hole might be a good .010" smaller than the top. It all depends on the material, the thickness, and the travel speed. It certainly can be more than that in some cases. The location of the holes and cuts will be dead on accurate, but a clean up on the drill press is still a good idea if a close fit is desired. The guy I've known and worked with here for years owns the same machine. You have to allow a smidgen of extra clearance over what you would allow with a machining operation to offset the taper. So one of the very first decisions has to be, how close of a fit do we want at the main and rail stud locations? Obviously the closer the fit, the more accurate the layout has to be. We can probably safely assume all the fasteners are parallel, and inserting and removing all the studs with the plate in position is almost going to be the only way to attach and remove it. But any slight variation in hole matching is going to result in tight studs if the hole size is too tight. I'd recommend a heavy sheet metal template for the first run. Obviously we have more leeway at the pan rails than at the mains. If you make the hole size the same as in the caps that should be more than big enough.

My center main cap is 9/16" proud of the pan rails at the center lug, the others are 1/2" or less. So I need at least a 13/16" girdle and 7/8" would be better. 1" is probably not necessary. That being the case, there is no advantage to me in using alloy steel and 1018 cold rolled is the most practical choice. For a flat plate (not stepped) alloy might be a good option, and even a tool steel might be considered if price is not a concern, allowing use of as thin as a 3/8" plate and still having great strength. But I doubt anyone is going to pony up for that, at least not on the first go around.

Finally, as long as we're doing it, go ahead and lay out the pickup spacer in one of the drops (where the crank throws are) and include it with the plate. The extra cost for cutting that out is negligible and it avoids making another part for those who choose that option. You might also ask the guy if he can do a rapid travel over the path for the cut line for that option to mark the plate for the cutout. If that works it won't weaken the plate and will eliminate errors.

For those of us who know a shop with a waterjet, it is probably cheaper to buy the steel locally and just give them the file rather than pay to ship the steel. That's the way I'd prefer to do it. (Setup is minimal, load the file and lay the material on the table.) If you have access to a drill press, a pair of counterbores can be bought for about $20 each so why pay a machinist unless you're making a stepped plate?

What did I miss? Oh yes, counterbores come either with replaceable pilots or with fixed ones sized for bolt clearance holes. Usually 1/32" over the nominal bolt size and it needs a little running clearance. Don't forget about the taper. If this seems like too much, you have to use a replaceable pilot type and cut a special pilot for it. This has the advantage of allowing you to cut different sized counterbores for a given hole size.

Jim

[sean Buick 76]

I am going to try to call Sony Seal one last time to try to get a hold of his template.

[Cali72's]

Whats the advantage of haveing the flanges?Im lost .

[Nothingface5384]

you may build youre own headers, i guess more specificly for cars with 350 swaps like the 64-67 cars or any non buick..or for custom turbo headers