XXO/BVGC '38 Chevy Coupe Build

[38flattie]

Chris, your line of thoughts are not much different than mine!

A few posts back, I mentioned that I would like to get this on a flowbench this winter. I've been thinking about this for some time, for a couple of reasons.

1) Everyone that I know that does port work, has at one time or another, voiced a similar fact- what they thought they knew about porting went out the window when the got their first flowbench! Don't get me wrong- Dale put an extreme amount of time in porting this thing, and it's bound to flow more than it did. The problem is,what does it flow? I think we really need to know this, to pick the cam that will give us the most power

2) Joe Abbin did the only flow work that's been done on the block, and with some port work, ended up with numbers barely better than a ported Ford flathead. Garry Odbert, who had the Caddy flathead powered roadster, ported and flowed his block, although not the same one he ran this year. Garry did minimal port work, based on the way that Mondello ported heads. Garry got about 14% more flow than the block I had at Abbins'.

So, have we maximized our flow potential, or just made it look pretty, with some improvement? Who knows! I do know that I haven't found anyone that is willing to flow this thing for me. I really want someone that's not associated with the build, and has no agenda.

The siamesed ports are a problem, as you well know. I talked to Dema Elgin at length today, and he is going to give me his recommendations on how he feels we should proceed. We may, in the end, try several different things, until we are satisfied that we've done all that we can do. I do have great confidence, that turning to Dema Elgin was beneficial to the build. I think this build has proceeded far beyond being content with 'gut feelings', and should proceed with decisions based on hard numbers.

The other big think Mr. Elgin was adamant about was our exhaust. He feels, and I can't argue, that we need to have a smaller,'tuned' set up, that will be of benefit to our power curve.

Oh yea, he didn't like my blower choice either! He feels that it takes far to many HP to operate, and a centrfigul blower would be a better choice. I can't argue, but the 6-71 is staying!

It's a Dodge good thing winter is coming, and not spring!

[Tman]

We miss you in the chat

[desotoman]

Buddy,

Put the parts you have together and get the motor on a dyno. Work with what you have. You will learn a lot. Second motors are always better than the first one, but it takes the first one to learn from. R&D isn't cheap, but you always learn from the past.

Flow benches are nice don't get me wrong, but just because you get more air flow does not equate to usable HP and torque. When I was working on my Flathead project, Mark Dee's asked me if I saw any airflow over the top of the valves, when I told him I did he told me that it was impossible. I asked why and he told me he had hired a guy to flow a Flathead head and there was never any flow over the top of the valve. Once I saw the head I understood why they did not get any airflow over the valve. My point is nothing is cast in stone, different chambers will flow different and that is not necessarily bad. It is the end result that counts, and that only comes from R&D.

I hope this helps,

Tom G.

[38flattie]

Tom,

What you say makes sense, and is the feeling of several of my team mates. I guess I want to achieve perfection, and in reality, that won't happen!

Car to share the head design that allows for flow over the valves? Email me pics, maybe?

[Milwaukee Midget]

Buddy,

Put the parts you have together and get the motor on a dyno. Work with what you have. You will learn a lot. Second motors are always better than the first one, but it takes the first one to learn from. R&D isn't cheap, but you always learn from the past.

Flow benches are nice don't get me wrong, but just because you get more air flow does not equate to usable HP and torque. .

Tom, there is validity to you point, and on an engine that can be readily had, or had more of a racing pedigree, I'd agree with you.

My disagreement is tactical.

Last week, the Montana Dodge Boys build gave out before they could turn it around to back up a record.

Gary and Mikes Straight 8 Buick also comes to mind - they windowed the block on the dyno, and then again on the salt.

In all three cases, Flattie's included, we're talking about vintage castings, all of which are getting harder to source, and despite prep and cautions, are working well beyond their design parameters.  They simply may not have that many passes in them, and a second motor, at least with respect to engines like this, becomes increasingly expensive to build.

IMO - and it's opinion, nothing more - tactically, I'd plan on getting only four runs out of it - a dyno day, a pass for class, a run and a back-up.  At that point, ALL other runs are bonuses.  In short, you need to achieve the goal before you wear it out.

In order to do that, it's got to be right, and right out of the box.  True, a flow bench doesn't guarantee more HP, but it can reveal mistakes and aid in proper cam design and header sizing for the particular application before you ever turn it over.

I've said "It's all a grand experiment", but a successful experiment minimizes the variables. 

I think flow benching should remain on the table. 

So there - two ways to skin a cat.

That's 4 cents I'm up to - this is breaking my race budget . . .

[desotoman]

Tom,

What you say makes sense, and is the feeling of several of my team mates. I guess I want to achieve perfection, and in reality, that won't happen!

Car to share the head design that allows for flow over the valves? Email me pics, maybe?

Buddy,

We all want to achieve perfection, nothing wrong with that. But IMO perfection only lasts until a part or technology is improved upon. So we may achieve perfection at a given point in time, but time marches on. I hope that makes sense.

I will share mine if you share yours. LOL.

Tom G.

PS. I am not against flow bench testing, just saying there are many ways to achieve the same results.

[38flattie]

Guys, you all have valid points, and I appreciate the thoughts.


Whan I was building the first FlaCad,and was indecisive as to what I wanted to do,  Rich Fox eloquently told me to quit talking about it, and do SOMETHING! Lol-I ended up with a LSR car!

I'm kind of in the same boat again. So, here goes!

We're going to assemble the engine, and get it over to John Beck in Chico, California. John is going to test and tune the engine on the dyno. If it makes the 500 hp I'm looking for, we're golden for now.

If it doesn't make 500hp, we'll tear it down, put it on the flow bench, design a roller cam, and see what we can do to get the 500hp.

So, if anyone is around, and wants to see the FlatCad fire up, B.S., or have a beer, I'll be in Chico Oct. 24-26th.

Tom, you have a Pm!

[desotoman]

Buddy,

Put the parts you have together and get the motor on a dyno. Work with what you have. You will learn a lot. Second motors are always better than the first one, but it takes the first one to learn from. R&D isn't cheap, but you always learn from the past.

Flow benches are nice don't get me wrong, but just because you get more air flow does not equate to usable HP and torque. .

Tom, there is validity to you point, and on an engine that can be readily had, or had more of a racing pedigree, I'd agree with you.

My disagreement is tactical.

Last week, the Montana Dodge Boys build gave out before they could turn it around to back up a record.

Gary and Mikes Straight 8 Buick also comes to mind - they windowed the block on the dyno, and then again on the salt.

In all three cases, Flattie's included, we're talking about vintage castings, all of which are getting harder to source, and despite prep and cautions, are working well beyond their design parameters.  They simply may not have that many passes in them, and a second motor, at least with respect to engines like this, becomes increasingly expensive to build.

MM,

I am very aware of the problems with vintage castings being fragile. But that is part of the fun in working with them. The Block is the weak link, and that is why it is a vintage class. I agree with what you have said so far, with one exception, it is actually easier IMO to get a block for a vintage engine nowadays with the internet, than it was say 15 years ago.

Tom G.

IMO - and it's opinion, nothing more - tactically, I'd plan on getting only four runs out of it - a dyno day, a pass for class, a run and a back-up.  At that point, ALL other runs are bonuses.  In short, you need to achieve the goal before you wear it out.

In order to do that, it's got to be right, and right out of the box.  True, a flow bench doesn't guarantee more HP, but it can reveal mistakes and aid in proper cam design and header sizing for the particular application before you ever turn it over.

I've said "It's all a grand experiment", but a successful experiment minimizes the variables.  

I think flow benching should remain on the table.  

So there - two ways to skin a cat.

That's 4 cents I'm up to - this is breaking my race budget . . .

MM,

I guess I did not explain myself very good. There are a lot of new parts some proven some not, made for this engine. When I suggest putting the motor on a dyno, what I did not make clear was the fact that I would not go for broke on making the most HP I could in the first run on the dyno. Instead I would run a low boost setting on the blower at let's say 5 lbs positive. Then I would work from there, and make sure the motor is happy. You also find out how the new components are working, and making sure they don't have any problems. After everything checks out OK, then you can decide what you want to do on Boost settings etc.

I do disagree with you on only getting 4 runs out of a motor. If I really thought that is all I could get out of my Flathead, I would have never ever started building one in the first place. Playing with these motors is a balancing act. IMO Detonation is your biggest enemy when running vintage blocks, and when you detonate you will find the weak link. That is why you need the dyno time.

I do agree with you on "It's all a grand experiment", but that is part that makes it fun. It is all about building a better mouse trap. A very expensive mouse trap. LOL. I hope this reply has made my first reply a little clearer.

Tom G.

Buddy, I just spent too much time on this post not to post it. LOL

MM, this has been a good discussion.

[38flattie]

Wow, Both of you guys bring up excellent points.

I agree that blocks are getting hard to find, and like everything else, they cost more now.

Chris, we may not even get 4 runs out of this block, but like Tom, I would not have built it if I really felt that's all I could get. We've taken extreme care to strengthen, modernize, and upgrade the engine, to give us the best chance of keeping it together.

Still, 'the best laid plans', and all....

Detonation is a big concern with the huffer, and hopefully the chiller will do what I'm counting on, and help us keep things manageable.

The main reason I'm dragging all this stuff to California, is to get the benefit of experience and knowledge that John Beck brings to the table. Like Tom suggested, we'll start with low boost, and work our way up.I'm sure John will be able to point out areas that need work, and the areas that are sufficient- at least that's what I hope for.

In the end, no matter how the engine performs on the dyno, it all could be a moot point. I saw a lot of very experienced builders, both blue collar and big money, have disappointing times on the salt.

In the end, the only thing that really matters is,can we survive 'the great white dyno'?

[Buickguy3]

  Each time we go it's with the caveat: Run what ya' brung, Break what ya' brought. Don't think we have ever returned home without something to rebuild. In racing you build it as good as you can, and break the weakest link. As George W. said, "This is not rocket surgery".
   Doug 

[SPARKY]

Wow       I thought that my design critera of 10 (20 passes) min. at WOT was wild!

[GH]

MM, the 1950 Buick straight  eight had run on the salt, Maxton Mile, and on the street for quite a few years until we started making more boost. That's when we started have problems, we repaired the first window with a steel plate bolted to the block. The second window, very large, was the straw that broke the camels back, so to speak. Mike is in the process in building an other engine, so maybe we will return next summer. I love these old things, as you probably know, I have built a street driven GMC 6 banger.

[Milwaukee Midget]

Part of my "tactical" thinking is that if you set the build standard and research level high, but keep the durability expectation low, you'll either be right, or pleasantly surprised.

It's the pessimist's credo. 

[Bob Drury]

  Let's see, Vancouver, Wa. to Chico, Ca............... let's see here, that's about a eight hour drive for a cold beer................  hmmm..................  by gosh, that might work.............
  For Christ sakes, don't break that dyno, I think they want to go 400 with that roadster........
                                                                  Bob

[maguromic]

Buddy, On the old iron as the boost goes up the cylinders will go out of round and their ugly head will pop up.  You can  control some of this by posting the cylinders (you need be precise on this) will keep the windows closed on the block.  This is what we are going to do on the GMC.  Also what is your piston speed? Tony