Port and Polish by Comiittee thread (Cool pics throughout)
#91
Nordschleife Master
I was also considering E85 if i went with a TT or flex type system where i could really dial up the boost when run on E85 to take advantage of its 100 octane rating. But I know theres more to it then just changing the ignition timing and fuel maps. There are mechanical changes that must be made.
I dont know if corrosion is the issue or if E85 is more of a solvent or can gum up more, i am not real familiar with it but you need to address those issues. The fuel pump may also need to be changed and come to think of it the plastic tank in the 928 may not be E85 friendly. I would suggest double checking all those things.
I would trust GM did their homework and they have some very specific changes that are made in flex fuel line as opposed to the same engines that are just gasoline. They may have more info on their website but probably not. Try the SAE website, there maybe some good info on there. I would be surprised if there were many books on E85 as its still a fairly new idea in its current state.
I dont know if corrosion is the issue or if E85 is more of a solvent or can gum up more, i am not real familiar with it but you need to address those issues. The fuel pump may also need to be changed and come to think of it the plastic tank in the 928 may not be E85 friendly. I would suggest double checking all those things.
I would trust GM did their homework and they have some very specific changes that are made in flex fuel line as opposed to the same engines that are just gasoline. They may have more info on their website but probably not. Try the SAE website, there maybe some good info on there. I would be surprised if there were many books on E85 as its still a fairly new idea in its current state.
#92
Rennlist Member
Thread Starter
I am pretty sure GM uses SS valves for all their flex fuel (E85) vehicles. There are also different hose compounds needed for fuel likes in the entire chassis.
Have you looked into that? IIRC they replace valves with SS and they use other injectors as well as specific type of rubber compound hoses. There is quite a bit to change inside the engine although if your buying everything new its not an issue, but hopefully you've got the correct fuel lines and injectors. Did you ask RC if their injectors are suitable for E85 or Ethanol?
Have you looked into that? IIRC they replace valves with SS and they use other injectors as well as specific type of rubber compound hoses. There is quite a bit to change inside the engine although if your buying everything new its not an issue, but hopefully you've got the correct fuel lines and injectors. Did you ask RC if their injectors are suitable for E85 or Ethanol?
The valves are not a concern - they may already be SS at least on the intake - not sure, but the fuel is not as corrosive as people thing - its confused with methanol corrosion-wise - not in your case, but all the time.
RC injectors - I bought some 72s. I may need even bigger, and I may use these, or sell them. If I use them, I will need to jack up the fuel pressure for more flow, which screws with the opening times, and makes them less exact.
But yes, everything is planned for this fuel, including the huge fuel lines and rails.
#94
Rennlist Member
Thread Starter
I was also considering E85 if i went with a TT or flex type system where i could really dial up the boost when run on E85 to take advantage of its 100 octane rating. But I know theres more to it then just changing the ignition timing and fuel maps. There are mechanical changes that must be made.
I dont know if corrosion is the issue or if E85 is more of a solvent or can gum up more, i am not real familiar with it but you need to address those issues. The fuel pump may also need to be changed and come to think of it the plastic tank in the 928 may not be E85 friendly. I would suggest double checking all those things.
I would trust GM did their homework and they have some very specific changes that are made in flex fuel line as opposed to the same engines that are just gasoline. They may have more info on their website but probably not. Try the SAE website, there maybe some good info on there. I would be surprised if there were many books on E85 as its still a fairly new idea in its current state.
I dont know if corrosion is the issue or if E85 is more of a solvent or can gum up more, i am not real familiar with it but you need to address those issues. The fuel pump may also need to be changed and come to think of it the plastic tank in the 928 may not be E85 friendly. I would suggest double checking all those things.
I would trust GM did their homework and they have some very specific changes that are made in flex fuel line as opposed to the same engines that are just gasoline. They may have more info on their website but probably not. Try the SAE website, there maybe some good info on there. I would be surprised if there were many books on E85 as its still a fairly new idea in its current state.
E85 and ethanol conduct electricity - thats the issue, as well as these materials do not lubricate. All this is no big issue as long as they are addressed - either with design or with things like redline's "Alcohol fuel additive" that adds some lubricity.
#95
Rennlist Member
Thread Starter
Yes, I have contacted a place that makes them in whatever shape I want - as I need one that is quite l large. It will be a street driven car, so i am taking great care in making sure it's usable every day, with reference to the tank, its size, and how fuel gets in it. I addressed some of this in my "cool pics" thread about the car assembly, I don't know if you saw that.
#96
Nordschleife Master
ok then
looks like youve already done your homework.
Ive decided i wont run my TT 928 on E85, i;ll just stick with gasolina! If and when i ever want 100 octane, i will just buy race gas.
I like that your going this route, but why did you decide to go E85? It sounds like its a costly conversion, although again if your buying A fuel pump and know from the get go that you want E85 the price difference may or may not be a concern. I am just curious why you choose E85, for environmental reasons or what? I was thinking it would be cool to claim its somewhat GREEN, but whats your reasoning?
looks like youve already done your homework.
Ive decided i wont run my TT 928 on E85, i;ll just stick with gasolina! If and when i ever want 100 octane, i will just buy race gas.
I like that your going this route, but why did you decide to go E85? It sounds like its a costly conversion, although again if your buying A fuel pump and know from the get go that you want E85 the price difference may or may not be a concern. I am just curious why you choose E85, for environmental reasons or what? I was thinking it would be cool to claim its somewhat GREEN, but whats your reasoning?
#97
Rennlist Member
Thread Starter
ok then
looks like youve already done your homework.
Ive decided i wont run my TT 928 on E85, i;ll just stick with gasolina! If and when i ever want 100 octane, i will just buy race gas.
I like that your going this route, but why did you decide to go E85? It sounds like its a costly conversion, although again if your buying A fuel pump and know from the get go that you want E85 the price difference may or may not be a concern. I am just curious why you choose E85, for environmental reasons or what? I was thinking it would be cool to claim its somewhat GREEN, but whats your reasoning?
looks like youve already done your homework.
Ive decided i wont run my TT 928 on E85, i;ll just stick with gasolina! If and when i ever want 100 octane, i will just buy race gas.
I like that your going this route, but why did you decide to go E85? It sounds like its a costly conversion, although again if your buying A fuel pump and know from the get go that you want E85 the price difference may or may not be a concern. I am just curious why you choose E85, for environmental reasons or what? I was thinking it would be cool to claim its somewhat GREEN, but whats your reasoning?
Its cheap race gas. I could even make it in my back yard. The reason I am looking at these heads closely is because i will need all the flow I can get for 25psi of boost - and there will be little chance of detonation even at that flow level with this fuel. It will also be down to 7:1 fuel ratio, so I need more mass to get out of the exhaust port as I mentioned earlier.
As you know, CA only has 91 octane. Its barely even that most of the time.
Race gas, in a perfect world, would be best, C16 all the time, but what is that, 8 bucks a gallon? 91 octane here is already almost 4 bucks.
Ethanol has great characteristics, and will be very viable in the next 15 years as I am sure you can guess.
I think you should take a second look at the fuel. You could start a new thread if you wanted and I could put some good links in.
#98
Three Wheelin'
Be careful opening up the area below the exhaust valves. I don't recall the number but the throat, the area just below the valve, should not be opened up as much on the exhaust side as it can on the intake side. The exhaust valves need greater area to dissapate the heat. They use a percentage of the size of valve you are using. On the intakes it is over 90% and on the exhaust somewhat less. I used to watch an old friend port heads and he was constantly checking throat size with a set of internal calipers. He also used the calipers to take critical measurements of each port to try and achieve conformity.
#99
Rennlist Member
Here are pics of my heads.
Just a couple of things to note. This is a stroker motor with 968 intakes and stock S4 exhaust valves. The intakes were port matched for Louies ITB adapter plates.
This particular machinest is highly regarded here locally, has been around for a long time, and isn't much for bench racing. He has a very realistic attitude about things which I appreciate. For parameters I didn't say make these the highest flowing heads that all your experience and skill can muster, he's familiar with my project so he knows its a 6.5L motor that is going to have a redline of about 6500rpms that it is not going to see very often. I told him to use his discretion as to what he thought would work best, and if he wanted to go full boat that was fine, or if just wanted to clean things up that would be fine too. I think he just took to cleaning things up abit. It's interesting that you folks mention about not messing with the short side radius. Before starting on my heads he did say it would have to be slightly altered since I was going with larger valves.
At any rate, take a look, lets see what you all think. I'm not going to have them redone regardless of people's observations, and I'm certainly not going to take any offense. Just curious how this very succesful engine builder's technique will hold up to Rennlist scrutiny.
Have fun guys, let's take off the gloves.
Intake:
Exhaust:
Chamber:
Seats:
Just a couple of things to note. This is a stroker motor with 968 intakes and stock S4 exhaust valves. The intakes were port matched for Louies ITB adapter plates.
This particular machinest is highly regarded here locally, has been around for a long time, and isn't much for bench racing. He has a very realistic attitude about things which I appreciate. For parameters I didn't say make these the highest flowing heads that all your experience and skill can muster, he's familiar with my project so he knows its a 6.5L motor that is going to have a redline of about 6500rpms that it is not going to see very often. I told him to use his discretion as to what he thought would work best, and if he wanted to go full boat that was fine, or if just wanted to clean things up that would be fine too. I think he just took to cleaning things up abit. It's interesting that you folks mention about not messing with the short side radius. Before starting on my heads he did say it would have to be slightly altered since I was going with larger valves.
At any rate, take a look, lets see what you all think. I'm not going to have them redone regardless of people's observations, and I'm certainly not going to take any offense. Just curious how this very succesful engine builder's technique will hold up to Rennlist scrutiny.
Have fun guys, let's take off the gloves.
Intake:
Exhaust:
Chamber:
Seats:
Last edited by atb; 03-17-2008 at 12:12 AM.
#100
Three Wheelin'
Join Date: Jan 2007
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Actually if your going to get pissy about something thats already been said, i made the same point on page 2, post #19. No need to get pissy about someone saying the same thing you did, as it turns out your not covering any new ground here.
No thats not at all what i am talking about. Either you don't understand the concept or I have done a **** poor job describing it.
The mod i am reffering to turns the combustion chamber into an inverse of a golfball, think MANY MANY dimples not a single dimple. The pistons were also modified and the results were mainly in the area of drastically reduced fuel consumption, something in the area of 20% - 30%, or the engine could be retuned to flow the same amount of fuel for no mileage gain and more air could be found to go in the engine and you could gain more HP to the same tune of 20%-30%. Mind you this was on small engines but if the principle works for 1, 2, or 4 cylinder cars then there is no reason it cant work for other's. I will see if i can find some more information on the theory.
If Chrysler is doing it, I hardly consider it cutting edge. Those cars are just giant, heavy, mass produced tin cans.
Sorry but the minute we start talking about american cars and 8V Chrysler heads in a Porsche Forum is the moment i run away.
No thats not at all what i am talking about. Either you don't understand the concept or I have done a **** poor job describing it.
The mod i am reffering to turns the combustion chamber into an inverse of a golfball, think MANY MANY dimples not a single dimple. The pistons were also modified and the results were mainly in the area of drastically reduced fuel consumption, something in the area of 20% - 30%, or the engine could be retuned to flow the same amount of fuel for no mileage gain and more air could be found to go in the engine and you could gain more HP to the same tune of 20%-30%. Mind you this was on small engines but if the principle works for 1, 2, or 4 cylinder cars then there is no reason it cant work for other's. I will see if i can find some more information on the theory.
If Chrysler is doing it, I hardly consider it cutting edge. Those cars are just giant, heavy, mass produced tin cans.
Sorry but the minute we start talking about american cars and 8V Chrysler heads in a Porsche Forum is the moment i run away.
oh please, Ryan......no one is or was getting pissy about anything.
Again, you've busted on me for a minor comment to something you said, even though I meant no harm or foul to you, or anybody else......
If I wanted to really fight (or watch a fight) with someone via keyboard, I'll go over to Pelican Parts and watch those sparks fly. It's getting pretty juicy over there......
--Russ
Last edited by largecar379; 03-17-2008 at 12:40 AM.
#101
Three Wheelin'
Join Date: Jan 2007
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[QUOTE=atb;5219898]
Have fun guys, let's take off the gloves.
I'd take the gloves off but some folks would probably be off in a corner (crying)....
nice looking heads, not to radical......
--Russ
Have fun guys, let's take off the gloves.
I'd take the gloves off but some folks would probably be off in a corner (crying)....
nice looking heads, not to radical......
--Russ
#102
Nordschleife Master
Sorry the above, ESPECIALLY the "CAN YOU SAY CHRYSLER HEMI" came off as trying to suggest Chrysler is on the cutting edge of performance or something. Sorry, if history shows us anything, american automotive manufacturers are the last to embrace any kind of new technology, and usually only when it becomes absolutely necessary. If and when they do its usually years since its been proven by the japanese or Germans, Also if there is ever a car line thats been the first to debut new tech, and proven itself to be an automotive innovator, its without a doubt got to be the Mercedes Benz S-Class. NOT A CHRYSLER! Yeah they used to be owned by the same company but Chrysler is looking like its going to sold off in parts and ultimately be dissolved in a matter of years by the looks of it based on how Cerebus is running things there.
I assume your a Mopar guy by your statement and thats fine, i don't care, but that comment came off somewhat arrogant to me as if I have no clue what i'm talking about. I am well aware of what auto manufacturers are doing, even the american ones. Which is usually really easy to understand because its what the Germans were doing 15 years prior.
Besides were Porsche owners and elitist aren't we? Arent we just supposed to hate american cars anyway, let alone dislike them because they are dinosaurs in the tech race. Hell, Chrysler is banking on "That thing got a Hemi in it" which was something they came out with in the 50's! Not to mention their new Challenger thats an even bigger, fatter version of the same, big fat, car for what, 1969? Sorry, thats NOT innovation, and mentioning Chrysler as a technology leader and automotive innovator is blasphemy to me.
Did i mention i hate American cars?
#103
Rennlist Member
Thread Starter
Those look really like high quality seats Adam. And I can see that the transition to the seat is smooth from the port. Did he put new seats in?
Seats:
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Seats:
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#104
Nordschleife Master
I liked Greg's point about bead blasting the intake ports and possibly the intake itself. I also liked the way you explained how air flows through a port and how the theory of why you want to rough up surfaces help airflow through the head.
#105
Rennlist Member
Yup, all new seats and all new valves, both intake and exhaust.
The valves were sourced through Worldpac. They are TRW's but had Porsche tags on them. The seats were provided by Motorsport SLC. I seem to recall Garrity was pretty particular where they were sourced from.
The valves were sourced through Worldpac. They are TRW's but had Porsche tags on them. The seats were provided by Motorsport SLC. I seem to recall Garrity was pretty particular where they were sourced from.