BSR GTU E31 Head Images

[SHADY280]

is that the 79 year #33 in the background? where is that? would love to see that car in person

[josh817]

Z-ya, I just got here at home and I measured the ports again. I was seeing 39mm intakes, 31mm x 40mm, and 36mm x 40mm on the exhaust. Head has 44mm intake valves and 35mm exhaust.

 

I know this may piss off Tony, but I'm curious if the ports should be slightly bigger, to compensate for a larger displacement. However a part of me is saying no because that's the higher velocity Tony was talking about, the difference between my future EFI and Z-Ya's carbs.

 

I am wanting to put in 46/38mm intake and exhaust seats and then use the regular 44/35 valves, like Monzter did. The port would have to be reworked a little bit to match the seats. Once I get the manifold I need I will need to see the difference between the runner and the port. Hopefully they aren't too far off, requiring a lot of grinding.

 

I'll have pictures when I get back to Arlington.

[z-ya]

is that the 79 year #33 in the background? where is that? would love to see that car in person

 

No, that is some sort of BRE replica. Nice car though. It was at this years convention. You know, the 40th anniversary of the Z car? There were three #33s. The twin turbo plus a C production car, and GTU 280Z. Also the Steve Millen #75, which we got to see on the track.

[z-ya]

Z-ya, I just got here at home and I measured the ports again. I was seeing 39mm intakes, 31mm x 40mm, and 36mm x 40mm on the exhaust. Head has 44mm intake valves and 35mm exhaust.

 

I know this may piss off Tony, but I'm curious if the ports should be slightly bigger, to compensate for a larger displacement. However a part of me is saying no because that's the higher velocity Tony was talking about, the difference between my future EFI and Z-Ya's carbs.

 

I am wanting to put in 46/38mm intake and exhaust seats and then use the regular 44/35 valves, like Monzter did. The port would have to be reworked a little bit to match the seats. Once I get the manifold I need I will need to see the difference between the runner and the port. Hopefully they aren't too far off, requiring a lot of grinding.

 

I'll have pictures when I get back to Arlington.

 

Sounds like you have been thinking about it lot more than I have. Tony's advice is worth listening to. I'm no expert, but I plan on using this head on a 12:1 87mm L28. According to Todd at Wolfcreek, it should be a good match. And since the head, intake and carbs came off the same GTU engine, I'm confident it will make good power.

[Tony D]

If it's going to have race gas in it anyway, 12:1 is low...

 

As for ports I already explained the difference between carbs and EFI, if the ports are 39mm, it's EXACTLY what I said: a constant taper from 44mm down to the backside of the valve to keep velocity increasing all the way to entry point.

If you are running 50's and run a 50 manifold, chances are damn good that the head side of the manifold will be BIGGER than the port in the head, and then the port in the head will have to be made larger to stop the step that will occur. This will not benefit from "Match Porting" it needs to taper all the way to the bowl area for proper results. You simple make a taper over an inch inside the head (definition of match porting) and you will upset flow due to the radically different taper introduced. A 7degree maximum taper over the length of the intake runner, from air horn to intake valve is what most describe as the most angle you can have.

 

I don't know where this other stuff is coming from, sometimes I shake my head at what conclusions people draw from what is said sijmply and in a straightforward manner. Some of this makes me realize the effects of 2+2=5 in the public school system. Everything is open to interpretation because it feels like it should be... OK, take the metal out. You will only ruin the head if it doesn't work. There are plenty out there simply get another one and make it again. Report on the results of the test if you 'wonder'... Sheesh!

[z-ya]

If it's going to have race gas in it anyway, 12:1 is low...

er

 

Yes, not a crazy CR. I have a new set of 15:1 pistons that have been shaped to match the head chamber that I can use. I'm going with flat tops. I'm not looking for a 1-2 race engine with max power. I want a reliable 5+ year race motor. One of the BSR boxes I have is what I call a "bad day at the track" box. I'm not looking to have another one.

[josh817]

I was thinking the same thing as you, if this head is kind of like a GTU head then it should make a good amount of power. Then I started having those ridiculous thoughts where I'm like

 

"Hmm velocity and CFM/volume are the two important things. I have a larger displacement thus I would need more volume?"

 

From there, the little people in my head argue back and forth until I become indecisive.

 

I still think I may grind a little on the head. The step for the guide on the exhaust side is still there a little bit. I would like to grind this completely away. The intakes look fine to me and as Tony said, same power from 45mm ITB to a 50mm carb but with smaller ports so no need to gouge.

 

Have to keep in mind that the gasket I use will have to have enough material to open up the holes. I think I may just have a copper one made. Last time I tried to drill/cut/press cut the intake ports out on the gasket, it turned out nasty.

 

Also as I stated, I'm wanting to go to the bigger 46/38mm valve seats with the regular size valves. Once again, still worried it will screw up something potentially great. My head may kind of look like yours but it could/probably will flow worse.

 

By the way my application will be an 11:1-12:1 89mm L31 which will have a rev limiter at 8000 RPM. 11 or 12:1 compression for the same reason Z-Ya said. I need to figure out my chamber volume and then decide on pistons. My chambers aren't welded up and will have a larger volume than yours for sure.

 

Not a crack in the port wall, just like... a pube or something... how did that get there?!

 

 

For anyone who was interested in the carb thing. Here is a 45mm Weber, this is at the back where the throttle plate is. The bore at the throttle plate is 45mm and the calipers show what a 50mm would be:

 

Here are the front dimensions. The bevel is 50mm and the bore after that is 48mm. If you went to a 50mm bore, that would be 50mm at the back of the throttle plate and then the front would have to have a 55mm bevel and a 53mm bore if you were to follow the 45mm carb dimensions:

 

The vent thing on the front opens up 3mm in, so you may break through if you went that big on this body:

 

This post will upset Tony. I was typing while he was typing, therefore I have written things he just mentioned. Lets see how this works out.

 

The common thing I see is that you don't like giving exact answer. I respect that, let us figure it out on our own, aim us in the right direction. However, that sort of system is inherently open to interpretation. If you don't say exactly, then some conclusions may be drawn that are incorrect. What else would be expected unless instructions were do exactly this, do exactly that. If you say "drill the oil hole out..." ok to what size? "Well figure that out..." Yes I could figure it out on my own, probably at the cost of an engine or two. Does anyone want that?

 

You have to realize a lot of us don't fully understand the science behind port flow. I wouldn't act surprised when you read some grotesquely wrong statement/game plan. Its a learning curve, not everyone knows the things you do, not everything is as straight forward as it might seem to you. Have some tolerance. I honestly think that we get too tangled up over the semantics of things to the point where certain technical threads lose their conciseness and the poor fellows (including us) have to weed through it all for the information they're looking for. Sigh. I don't think I'm going to participate in anymore back and forth "you're wrong, no, you're wrong too" attitude.

Edited October 25, 2010 by josh817

[Leon]

You have to realize a lot of us don't fully understand the science behind port flow. I wouldn't act surprised when you read some grotesquely wrong statement/game plan. Its a learning curve, not everyone knows the things you do, not everything is as straight forward as it might seem to you. Have some tolerance. I honestly think that we get too tangled up over the semantics of things to the point where certain technical threads lose their conciseness and the poor fellows (including us) have to weed through it all for the information they're looking for. Sigh. I don't think I'm going to participate in anymore back and forth "you're wrong, no, you're wrong too" attitude.

 

I keep telling you (and anyone else that's interested) to buy that engines book and read it. Invest in knowledge. Seems nobody ever takes up that offer. I guess that's the difference between someone that knows what they're doing and 1000 monkeys trying to write a novel...

 

[josh817]

I keep telling you (and anyone else that's interested) to buy that engines book and read it. Invest in knowledge. Seems nobody ever takes up that offer. I guess that's the difference between someone that knows what they're doing and 1000 monkeys trying to write a novel...

 

You told me that, what, 3 days ago at most? Sounds reasonable for me to purchase and have read them by now. Have you gotten the Kas Kastner books I referred you to? Do you have any knowledge from your books that pertain to this thread that you would like to add? Thats with absolutely no sarcasm intended, I really am interested in what they say since I don't have them.

[Leon]

The reason for my reply was that you sound as if you are complaining about your lack the knowledge on the subject. Instead, educate yourself (from the right sources).

 

Here is my game plan: read, understand, test, analyze results. You can theorize all you want, but in the end, you're going to have to physically do something about it. When it comes down to making modifications you have to understand that failure is part of the game. I try to make my approach nondestructive when it comes to valuable parts for two reasons; (1) it costs $$$/time to replace and (2) those gains are likely to be minimal in the scheme of things. Sure, bore out a 45mm Weber to a 50mm but what will that really get you? Want to find out, then do it. Alternatively, use a 45mm carb and focus on something else, maybe it will be more worth your while. That's what it takes.

[josh817]

That's not what I was complaining about, I wasn't really complaining about anything. I was making a comment towards Tony to have some tolerance. We are far past the carb thing and into another realm. Fuel injection and head preparation is what we are at now. You are right it will cost time and money if I kill a head, however head work would yield important power, not minimal. I'm sure you can understand that I want to get it right.

 

I can't assume my head performs as well as Z-Ya's GTU head. It probably doesn't. I don't know who did the head work. I know when I bought the head I also bought a Don Potter camshaft, maybe its his work which means its good, but I don't know if it is his or not so...? The head could be nothing and in that case I'll dig into it, the head could be special and in that case I want to preserve it. Can you see the conundrum now?

 

 

 

In fact, lets just not worry about it. I'll take my questions elsewhere.

Edited October 25, 2010 by josh817

[Tony D]

"This post will upset Tony. I was typing while he was typing, therefore I have written things he just mentioned."

 

No it won't, this stuff is standard on any engine, and any port. The reason you wrote things I mentioned is because these things don't change.

 

The common thing I see is that you don't like giving exact answer. I respect that, let us figure it out on our own, aim us in the right direction.

 

Some of that is what is going on, but I don't feel I need to type over and over stuff that is extensively documented elsewhere. If you are asking for an exact spoonfeeding of information that is already out there if you look...welll that ain't gonna happen!

 

However, that sort of system is inherently open to interpretation. If you don't say exactly, then some conclusions may be drawn that are incorrect. What else would be expected unless instructions were do exactly this, do exactly that. If you say "drill the oil hole out..." ok to what size? "Well figure that out..." Yes I could figure it out on my own, probably at the cost of an engine or two. Does anyone want that?

In the oil hole instance, someone asked about a particular thing and I believe my answer was "Why don't you call Frank Honsoweitz at Ed Pink Racing Engines and ask HIM instead of posting queries and getting vague responses by nobody who knows a damn thing." And I do believe he did, and got the EXACT answer he wanted, and then POSTED it. Why would I tell him when some internet a-hole would argue with me---EVEN THOUGH I would give you the same answer at Frank... If he calls Frank and gets FRANK'S ANSWER who will be able to argue with it? Nobody, he wrote the book and HIS MEANING is exactly what he will give you. Not someone else's interpretation of what Frank wrote. As for exact answers, it doesn't work like that. You are unskilled and your insistence that a 'one size fits all' answer is possible. That is a foolish position to take. In many cases ther IS NOT AN EXACT ANSWER. The more you get into building serious stuff, you realize that EACH ENGINE will be different. Major dimensions will be one thing, but the difference between a stock engine making 120HP on the dyno and the same components making 209HP in a competitive ITS engine is not something you will easily share by saying 'tab a into slot b with a 0.040" cut...' It doesn't work like that. As Leon says, you are getting upset at your own ingorance on the subject, and blaming other people for not spoonfeeding you EXACTLY what you want NOW NOW NOW! Well, as said above "that ain't gonna happen" when the stuff is already out there and documented already. That is not what this site is about. I'm tolerant as hell, but when someone comes insisting they are entitled to exact answers for their particular problem...well cut me a f-ing P.O. my rate starts at $1250 a day, and then we can talk about your EXACT situation. But discussing your EXACT situation doesn't help the other guy now does it.

 

Referring him other sources where he can learn the theory behind the answer will...

[Gollum]

So tony, what coil-overs do I need for my car again?

 

 

I honestly get his point though it took me several years to really take this concept to heart. We have so many threads of people asking "which engine should I go with" and "my stock brakes suck, where can I get some brembo's for my car?" These are questions that tell more about the person asking than we could possibly give them back in information. They don't really know what they're looking for and the best a good samaritan could do would be to point them towards finding the right question.

 

Like the whole injector question. The real answer is that you can put as many injectors just about wherever you want and be ok. It's all in how you want to tune that system. For quite some time companies got away with basic throttle body injection on V8 engines. Sure it sucked like hell, but the problem wasn't in the inherent concept, but the way it was applied. So even in those cases someone might say "TBI sucks" showing their ignorance, because the idea doesn't suck, how it's been done sucks in many cases.

 

A community can only be as strong as their communication allows them to be. If we fail to learn how to communicate then what we're doing here is pointless.

 

Go hand around some serious F1 forums and you'll find many debates on how to use words and what their definitions should be. Because if we can't use words that mean the same thing to everyone then they're pointless.

 

This thread has had some of the most spoon fed info I've ever seen from Tony, which is actually high praise that he's that interested in responding... Tony has more experience than many of us will ever come close to comprehending, and his advice and explanations shouldn't be taken lightly. That's not to say lift him up like a god or something. We have MANY people that are members here that are like Tony, which is why newcomers need to be so careful at times. Posting here is like getting to speak and ask questions at a panel discussion with race teams. Know your subject matter BEFORE standing up and making a fool of yourself.

 

I say all this because I learned the hard way myself. Go back and read some of my earlier posts. I've been an utter newt at times.

[Tony D]

"Posting here is like getting to speak and ask questions at a panel discussion with race teams. Know your subject matter BEFORE standing up and making a fool of yourself."

 

This is a good point. In my case and several other people I work with, we have spent more hours than you think seeking out the information referenced in vague terms in many of hte reference texts dealing with the L-Engine. In once particular instance someone quite well known was contacted. Nothing was insisted upon, but rather, a reference was given about checking out Land Speed Records if they wanted to know some more about what we were doing.

 

Several days past, then a week. Reports started to trickle back that people were asking questions about us... and then out of the blue the targeted individual calls back and puts forth a flood of information we vaguely asked about, then went into detail about more... and finally gave us a personal phone number to call if we had any more questions.

 

What gets me is WHEN I DO TRY TO DIRECTLY GIVE THIS INFORMATION OUT, people refer to it as 'hear-say' and demand documentation. Well, I'm not giving out the guys personal contact number. That was given to me in confidence. That I TRIED to share it was my effort at conveying it. There's little more that can be done---be a skeptic and miss out on the information. Eventually you will have it confirmed on your own...or not.

What I have found in the VAST MAJORITY of cases is that generally the knowledge gained is NOT SPECIFIC to the engine being developed. It's known by many different people in many different fields. It's not God-Knowledge, but what it does require in many cases is CROSS-DISCIPLINARY inquiries and a sharp enough mind to know what questions to ask. When you get someone like a team or engineering development manager on the phone who DOES know all these inter-related questions, the flood gates open up. They see you are at a level where you can handle the information they put forth. Specificity can be mind-numbing. Ron at Isky can literally talk for an hour on aspects of cam design. I don't deign to waste his time trying to impart it to me, it won't do me any good. And learning when to defer to a specialist is a key in good engine development. You can NOT know it all, you can have a good general knowledge, but likely you will get more farming out aspects of the job to someone who KNOWS his SPECIALITY far better than you will ever command it. Good managers know where to get the best people, they DO NOT try to know it all, nor do they waste time trying. Specifics are for hands-on workers and skilled trades. You won't win a race knowing what particular valve angle to put on a seat. You will win races knowing that beryllium copper is likely a better material than brass, and this guy at X Shop knows how to put in the seats so they never come out!

 

What it takes, primarily, is an open mind to NOT think like the herd when dealing with lower-level paradigms and myths that are propogated on the internet...but rather a lot of hard footwork progressively working up the ladder of knowledge diligently and asking a lot of questions along the way.

 

YOU WILL ONLY BE ABLE TO DIGEST INFORMATION WHEN YOU ARE READY TO DO SO---TO HAVE IT HANDED TO YOU WHEN YOU WON'T UNDERSTAND IT IS LESS THAN WORTHLESS, IT'S DANGEROUS AS YOU LIKELY WILL TAKE AWAY THE WRONG CONCLUSION DUE TO INEXPERIENCE OR IMPROPER TRAINING IN OTHER FACETS OF ENGINE BUILDING!

 

The answers and questions people give tell a lot about where their level is...if you're an 18 year old kid building his first engine most top NHRA builders will NOT give you specifics, they will give you generalities to best help you along the path. You are not ready to build a 10,000 HP engine, though you want to and think you are ready. They will give you the solid basis for the next step. You don't learn Hakatsuru the first day in Karate Class, you learn Pinan Sho. Or before that, how to fall. You learn and practice falling a LOT before you ever actually do anything!

 

It's not God-Knowledge like Gollum was talking about, he's absolutely right in most respects to what he says. It's simply a matter that I've been asking directed questions, and seeking out the TOP PEOPLE in particular disciplines for now going on 31 years CONSISTENTLY AND VORACIOUSLY and if I had more time, I'd give more time to it. The only way you are going to get to this level is not by getting spoonfed answers all at once---it's a process that takes 31+ years. It's not The Matrix where we hook up and ZAP! "I know engine building!" Oh how I wish it were.

 

No, in the real world you have to use patience, intelligence, and humility in some cases to garner the building blocks. Rome wasn't built in a day and most likely neither was a good running L-Engine. You have a long path ahead and the older the engine, the older the experts you will have to consult. One head builder couldn't get the flow he wanted on JeffP's head. He took the head to his DAD who originally ported and developed the Electromitive heads. Dad did something because it flowed a heluva lot more when it came back for testing.

 

And you couldn't SEE what he did. It LOOKED identical.

 

THAT is when you need to be REAL humble, and start asking questions to figure it out. It wasn't something cookie-cutter, that's what got it where it was on the first try. What got it to it's final stage was something SPECIFIC done to THAT head that a guy in his 70's noticed and applied. To learn what he did to identify what specific technique to that head is invaluable----if you are a head porter and wish to make a living at it. As a race team manager, or crewman, or owner of the car...it's an interesting bit of trivia and likely you shouldn't clutter your mind with it. JeffP is getting offers from people to 'do all your head work for free' now... Hmmmm, someone want to reverse engineer some stuff? Talk about humility! FREE WORK?!?!?! That is someone who WANTS TO KNOW!

 

The important point is if you don't find these people before they die, and milk them like sponges for their knowledge, it will DIE with them and it will be HELL 'rediscovering' what it was they knew for 50 years before their death.

 

Respect your elders, they really do know more than you do. And if you approach it right they are more than willing to share. But if your an a-hole about it, they are also content to be satisfied to know what they know and die that way. I know I am.

 

The person who looses is you.

Edited October 27, 2010 by Tony D

[josh817]

Hey Tony, look'it what got!

 

I'll need to buy two more similar air horns. Kinsler has some in the right diameter but only 6" long. Product hasn't arrived yet but I'll need to see if there is a lot of taper to the air horns pictured, otherwise I'd like to cut them down to 6" to match the Kinsler ones.

 

I'll make another thread so we don't fog this one up. In the next thread I'll try my best not to ask for direct info. I've already got a plan in down but its the technical stuff with injectors and megasquirt that I may need to look around for.

Yayyyyyy

Edited October 29, 2010 by josh817

[Tony D]

where you get those?

[josh817]

On the internet, a series of interconnected tubes. Needs 2 more air horns and then the two center throttle plates were missing too. Luckily all those parts are cheap.

 

No but seriously, wait until I get home and I'm on my computer so I can find the source.

Edited October 31, 2010 by josh817

[Tony D]

It looks like a Hilborn system, not the Eggers and Vickers, plus it looks longer. Definately it's a carburetted intake bolt pattern.

[josh817]

It's a Hilborn system. Came from Krista Potter. She said Don was trying to retrofit it onto a 4 cylinder motor or something and that's why there are only 4 ram horns and its missing the two center throttle plates. Maybe he was planning on cutting the manifold up a little... Hopefully he didn't already do that.

[Tony D]

Yep, that's how you do it, cut out the center two barrels to make it fit on the L4.

Same for the L28E manifolds. Though I don't know why someone would want them, the L20B(E) manifolds and L18E (SSS) had far larger runners than the L-6 manifolds did. They just didn't offer those engines here, we got the LZ18

 

Doesn't look like the manifold is cut. Getting new tubes shouldn't be a problem. Very interesting placement of the injectors on that manifold, my Hillborn has the injectors on the bottom and MUCH nearer the throttle plates.