high compression

[Raven]

Ok Heres something i've been thinking about.
Rebuilding the engine sometime and having the cylinders bored and the head too. Doing this, I'd need bigger pistons. Now there are three type of pistons. 1 dish (like we have) 2 flat (higher compression), and domed (Highest compression) i'd like to get flat or domed pistons. and of course i'd need a lot better rods than any stock ones. to do domedpistons i'd either have to have shorter rods or, raise the head up some with a thiker gasket. Also higher compression means you can only run race fuel (110+). otherwise you get bad problems. (not sure what exactly) and if i could get 14-1 compression i could run alcohol safely. and have lots more power that way. now what my Question is, Has anyone tried this yet? or anthing simular? What can our head hold for compression pressures? (suppose it's only as strong as the bolts holding it down) Any comments? Thanks.

[gerknme]

i have 9.5/1 je pistons. 14/1 sounds pretty high! i posted here about my compression and everyone told me not to do it, but too late. anyways, i dont have any problems so far but 9.5/1 and 14/1 are two different worlds. good luck with your project!

[Friends_Got_Dsms]

I think I read someone's sig and it said 11:1 so it's not a lot higher. If you got a spare ride and cash go for it.

[CobaltGSX]

i dont think it would very safe to run 14:1 compression and turbo...

[Friends_Got_Dsms]

No one said it would be safe but if it worked it would be awsome. Use Puater Rods, they are the best I have seen

[verserv]

14:1 would be like 4psi on pump gas i think

[Raven]

4psi means nothing. Because thats only when you have it spooled or spooling meaning you have drag on the engine causing the exahust to spool the turbo. you have 0 drag at idle even if you turn the idle up till you lean out and blow the motor up it won't have that PSI 14:1 is that. your compression won't change no matter what. unless you up the pistons and head. the only way to run alcohol is at that compression. thats why i was asking. Thanks.

[Nick 92 TSi AWD]

Um 14:1 on any car is nuts, turbo charged car, no it's not gonna happen. 8.5:1 is about right, 9:1 is a little high, 9.5:1 is entering race only, and 10:1 is race only/stupid. A 4G63 likes a lot of boost, look at your head ports, they're not big for velocity. Wait a minute why the hell am I even trying to explain this, nobody has any clue what the hell I'm talking about anyway......

Don't run over 9:1, ever. Don't run alchol, do you have any idea what that does to your oiling system?

[Raven]

I was talking for Race only application. Trailer car.. Drag Strip only.like the Big cars that run it.. with blowers and all. they have to do a timing belt change and belt change after almost every pass. the really big runners. yeah it is nuts.. but if you'r going to win you may as well do it the best way known. OTHERWISE you can reinvent the sport and find a better way. eitherway. :O) i wanted to have a race only car. and yes it would only run a couple times. till it needed a rebuild. know those Nascar cars? they do a full engine rebuild after every race. may not need it.. but just to be sure.
of course no one here has the money to do something like that but eh. just trying :O)

[gerknme]

Nick 92 TSi AWD

what are your thoughts on 9.5/1. you said entering race only? i have that compression, but im only running 9lbs on a 20g until i get my fmic installed. i plan to daily drive her!

[jasen]

Talk about building a one-run wonder. Forget stronger rods, you'll burn holes right through the piston heads, warp the valves, and crack/melt the spark plugs. Detonation is great... for fireworks. Keep dreaming... :)
If it was possible, don't you think someone would have done it already?

[Nick 92 TSi AWD]

By entering race only by no means do I mean it won't work, just that to run decent boost you'll probably need race gas. I can't see running much over 16psi on squirel pee pump gas with that high of compression. 116 octane works wonders though......but hey I haven't actually tried it myself so maybe you can prove me completely wrong. I actually I'd be happy if you did, that high of compression would mean really good gas mileage.

[Raven]

It would only be able to run on something like 110+ you wouldn't be able to run anything lower. thats the peoblem.. so yes it'd be race only. if it were possible do i think someof you guys would have done it already? No. i don't because as true to "all" DSMers as what i've been told. They're cheap. so. No i don't think anyone would have done it. sorry to insult anyone who' not cheap but. hey it's what i've been told. yes ofcourse you would melt the pistons and destroy your block IF you use cheap parts. you use some high quality high strength parts no i don't think you will ruin your engine. you'll have to pay a WHOLE lot more for the parts but you pay for what you get.

[Toast]

Originally posted by Raven
14:1 is that. your compression won't change no matter what. unless you up the pistons and head. the only way to run alcohol is at that compression. thats why i was asking. Thanks.

Who gave you that idea? Only way to run alcohol is to have 14:1 compression?!? WTF? You can run the same compression ratios with alcohol as you do normal petrol. On a NA motor, you can raise the compression to about 14:1 max running straight alcohol. Throw all the tricks in the book at an engine and you might be able to run 16:1. There's no such reason you should be running that high pressure on a turbocharged engine. You are almost entirely negating the benefits of a big FMIC as you'll be limited to low boost. Furthermore, you'll be placing a huge increase in load on the cooling system with that high of a compression ratio.

Um 14:1 on any car is nuts, turbo charged car, no it's not gonna happen. 8.5:1 is about right, 9:1 is a little high, 9.5:1 is entering race only, and 10:1 is race only/stupid.

Yep, I agree on that

Wait a minute why the hell am I even trying to explain this, nobody has any clue what the hell I'm talking about anyway......

Oh come on... there are people who understand ;)

It would only be able to run on something like 110+ you wouldn't be able to run anything lower. thats the peoblem.. so yes it'd be race only. if it were possible do i think someof you guys would have done it already? No. i don't because as true to "all" DSMers as what i've been told. They're cheap. so. No i don't think anyone would have done it.


Whoa... You're sitting here insulting DSMers by calling them cheap. Sure, there are plenty of cheap DSMers. But there are also DSMers who have the money to do what you propose. Fortunately for them, they also have knowledge. Something you seem to lack on this subject. Running alcohol is nothing new. There are no secrets about it's availability or use. It's not a unique idea. It was passed over because it isn't the best option.

It seems to me you don't have the faintest clue on what it takes (and costs) to convert to an optimal full time alcohol system. It is a lot of work, a lot of negative tradeoffs, and a lot of money. The reason you don't see this done is there is zero reason to switch over to an alternative fuel until you've maxed out the potential of race gas. I don't see you making more power than Buschur or Extreme so I don't see your logic.

Consider that you will have to replace/add the following to convert to alcohol

1. Standalone ECU . Hope you know how to tune with alcohol as it is different than with gas
2. Huge injectors, at least 1440CC each. Most likely will need staged injection
3. Completely replace the entire fuel system. There is ABSOLUTELY NOTHING in our fuel system that is compatible with alcohol. The gas tank, pump, lines, rail, regulator, etc. It all has to go and the stuff you replace it with is mucho $$$
4. You need some way to preheat the manifold to enable liveable cold start
5. Whoops, you need a new intake manifold with redesigned injection ports
6. Hope you have a good sense of smell. Colorless alcohol fires are kinda hard to put out. Good thing all racing organizations require an onboard fire system when running alcohol
7. Vapor lock becomes a serious issue
8. Gas mileage... what's that??? And alcohol isn't cheap
9. List could go on but I'm tired of typing...

sorry to insult anyone who' not cheap but. hey it's what i've been told.

Maybe you should stop listening to what other people tell you and do some research on your own...


yes ofcourse you would melt the pistons and destroy your block IF you use cheap parts. you use some high quality high strength parts no i don't think you will ruin your engine. you'll have to pay a WHOLE lot more for the parts but you pay for what you get.

It's not just the quality of the parts. It's the knowledge that goes into building such a car. All the expensive parts in the world won't do you any good when you don't know what the hell you're doing.

[Raven]

Look it's OTHER dsmers who have told me that every one is Cheap esp. 1 gen owners. and i was insaulted. s'queeze me for not knowing it all. i'm ASKING thats why i wanted to know. and i was hoping someone could Kindly shed light on these subjects to me.. how the hell do you know so much? hmm? you ASKed someone. you weren't born with it all in your head already right? so quit bitching me out for asking? Who told me i had to have that compression? someone i know who Races with it. And a few other Mechanics. I've been told it can't be done with our engines because "it's a Talon" well i hate that reason so i'm trying to find a good reason it can't be done. others have done it? Who? i know of no one.. no one on this board anyway. else they'd have written here. I would like to do it This is the Advanced topic list.. not the Advanced user list. ;) so i'm here trying to learn something advanced. and i get shot down ONCE again. because no one has the FING patience or wants to make the time to be nice and tell me how.. instead they'd rather make short jabs and so i feel like this DSM club is all a bunch of shit. i know people who have DSMs and know Nothing about the club and a lot of thier cars are nicer than what i've seen here. so.. to be honest with ya all? I think you guys Do suck.. most of ya anyway. the good ones either stay quiet and figure "he'll learn" where will i learn?!? no where i guess. go thanks for finally shedding light on the subject and to the rest of ya. (_(_)<-- kiss it

[Toast]

Originally posted by Raven
s'queeze me for not knowing it all. i'm ASKING thats why i wanted to know. and i was hoping someone could Kindly shed light on these subjects to me..

Ok, I admit no one had explained the reasons why. but everyone so far has told you it's a bad idea. It didn't seem like you wanted to accept that idea. On the reasons that people are too cheap to try it out.

how the hell do you know so much? hmm? you ASKed someone. you weren't born with it all in your head already right? so quit bitching me out for asking?

I admit I did get a little short with you and that was a little uncalled for. But you asked a question and got some valid responses (although not too great in detail). Yet everytime you've gotten an answer, you've blown it off with some (often incorrect) facts. Hell you flat out insulted other DSMers in your last post (even if they weren't your words). Implying that you won't have problems because you aren't cheap like "all DSMers." So I ask why the hell did you even ask a question in the first place if you don't feel like listening to the answers?

Also, I don't ASK very many people for information. At least not on objective matters. More often than not I end up getting different answers from every other person. First place I turn to is books, papers, etc. Reliable resources. If you have the time to do the research, more often than not you can find out most of the answers on your own.


Who told me i had to have that compression? someone i know who Races with it. And a few other Mechanics.

Perfect example of why you should always double check what you've been told. The info you got was wrong. They might have slipped up or there may have been some miscommunication. Can't always take everything for granted.

I've been told it can't be done with our engines because "it's a Talon" well i hate that reason so i'm trying to find a good reason it can't be done. others have done it? Who? i know of no one.. no one on this board anyway. else they'd have written here. I would like to do it

I agree with your thinking. You don't need to accept the reason "just because." But, don't expect to find answers like these on any message boards. Alcohol powered cars are at the pro level of competition. I doubt very many (if any) of those types of guys hang out on boards like these. Especially with us po'or folks ;) Closest example I can give you is that a few years ago a MR2 was converted to dual fuel. Both alcohol and regular gas. I think it dynoed somwhere in the 800HP range on alcohol with race gas #s about 100HP below.

This is the Advanced topic list.. not the Advanced user list. ;)

Point taken.

But it's so i'm here trying to learn something advanced. and i get shot down ONCE again. because no one has the FING patience or wants to make the time to be nice and tell me how..

May I suggest that you take perspective here. No one is being payed to sit here and type responses. And a message board isn't always the best source for advanced technical information. If you really want to know that badly, I suggest you head down to the nearest university level science library and start reading. 2nd, if you want a decent response, you need to word your questions better. Go look at your posts in this thread. You only asked questions in your very first post. You NEVER asked anyone to explain if this is possible, why wouldn't it be possible, pros and cons, etc. It's no wonder no one took the time to explain anything. It's because you never asked.

instead they'd rather make short jabs and so i feel like this DSM club is all a bunch of shit.

True that isn't the friendliest of attitudes. But by the same token no one is going to sit here and hold your hand. Hell half the people making jabs probably don't know what they're talking about. So who cares what they say? It's not like you know them personally or give .02 about em

i know people who have DSMs and know Nothing about the club and a lot of thier cars are nicer than what i've seen here. so.. to be honest with ya all? I think you guys Do suck.. most of ya anyway. the good ones either stay quiet and figure "he'll learn" where will i learn?!? no where i guess.

Where?!? Open your eyes and look around you. You have a world of information around you. Among the best support for ANY car club. You have countless VFAQS, dsm.org, Talon Digest Archives, 1000Q faq, vendor sites and support, tons of bulletin boards, mailing lists up the ying-yang, IRC (ok stop laughing :) ), DSM Manual CD, regional clubs, etc PLUS the resources of OTHER car clubs. If you took the time to sift through and absorb all the available information, you'd have the answers to virtually any question you can come up with. If by that time you couldn't find an answer, then it's time to look for some good book material. Complaining that you'll never learn because no one will spoon feed it to you is a very LAME excuse.

go thanks for finally shedding light on the subject and to the rest of ya. (_(_)<-- kiss it

LOL..... :)

[Nick 92 TSi AWD]

If you look around at my posts you'll notice I never ask anybody questions. Yeah I did at one time and you know what? I usually got completely wrong answers. Now I read books, talk to engineers, and talk to the professors at western <where I'm transfering to finish my mechanical engineering degree>. It gets you a lot better results than internet racing ;).

All the actual fuel supply demand problems aside with alcohol, there is another large issue. Oiling. Alcohol strips the thin coat of oil off the cylinder walls. This leads to greatly increased wear on the cylinder sleeves and piston rings. It will not work with conventional oils. When castrol made their alcohol fueled turbo civic their engineers made a custom molecular structure just for that aplication. Somehow I highly doubt you have chemical engineers at your disposal.....
To make an alcohol fueled drag car I can't see it getting done RIGHT with much less than $70k minimum....



DSMers aren't all cheap, they just tend to not waste money. Everything is a tradeoff, some people only care about the final result <ie power> and nothing else. Who cares if it's pretty if it gets the job done?

[Z1500]

This shit cracks me up. A guy who lists his shift knob after his signature is going to build a 14:1 turbo DSM and show all the stupid <ADMIN EDIT !!!> like Buschur how it's done.

Kevin 90GSX

From Rdy2race:
kevin,
watch the language or you will be removed I suggest that you READ the statement that you agreed to when you signed up

BM-
Rdy2race

[Edited by Rdy2race on 07-10-2001 at 02:49 PM]

[Nick 92 TSi AWD]

Originally posted by Raven
4psi means nothing. Because thats only when you have it spooled or spooling meaning you have drag on the engine causing the exahust to spool the turbo. you have 0 drag at idle even if you turn the idle up till you lean out and blow the motor up it won't have that PSI 14:1 is that. your compression won't change no matter what. unless you up the pistons and head. the only way to run alcohol is at that compression. thats why i was asking. Thanks.

HUH? Verserv was saying there's no way you could run more than 4psi of boost pressure. I'm not quite sure what the hell you're talking about.

[Tevenor]

Originally posted by Raven
This is the Advanced topic list.. not the Advanced user list. ;) so i'm here trying to learn something advanced.

Its also the Advanced Questions forum. Asking the questions the way you did is like trying to have someone tell you how to make a homemade deep dive liquid oxygen unit when you are still holding your nose to jump in the pool.

Some people on this board are known to be a**holes. Some know what they are talking about. Some people don't. Often the people who know their shit from actually doing it and not bench racing come off as assholes because of situations exactly like this. I know enough to be dangerous but thats about it and hence why I leave the good answers to people who know their shit.

If you came to this board to learn, then learn. Keep your ears open and ask good questions. If someone tells you your thinking is wrong, consider that it just might be that. Wrong. Thats how you learn. It does you no good to come asking questions then rip on the people who are actually giving you good information just because it doesn't jive with 'what you've been told by other DSM'ers'.

[Rdy2race]

Tevenor, Very well put. I know Nick, he knows his stuff but gets very fustrated with people some times B/C of the Q that is asked. Just like your comment about jumping in the pool. this Q was on the same lines,

Ravin,
You must take the "net" with a grain of salt as there is so many people that DON'T know and the ones that know are not always ready to give that info up so easy. it took people like my self and Nick and the others, ( toast, he knows a good amount as I have seen ) have spend so much time reading tech info and asking Q's to people WE KNOW have answers and are not weighed down by some sale pitch, they give us good info to work on and with. Also when you come back with replys like

" 4psi means nothing. Because thats only when you have it spooled or spooling meaning you have drag on the engine causing the exahust to spool the turbo......."

other then this being greek to me ( TRUST ME I know my S*&T) it makes no effort in trying to understand why they said that. Asking " Why 4 PSI? " would have been better. When you come back with a reply like that get ready to be taken to school. Us tech-E guys are like that and take offence when we can see you really don'w know.

Toast, Good post man keep it up.

Z1500 keep it cleen please you a Nubie so please read the "we have seen this before"


SOOOO Now that we are SOOOO far off topic I ask that we get back on it or I will lock this. the Q was a good one and warrents to be answered and YES I asked 1 MILLION Q's when I first started but the people I was talking to were a different group. They had time for this. There weren't 4 million web pages with BS combo and telling you to yank the lower honeycomb and bump the timming to 10 BTDC on pump gas. Now you have this and you need to sort through all this and not pick what you like but what is the truth. this is where DSMtalk comes in and the members that make this place so god dam good !!!!

So I bid you good luck. IMHO 9:1 is a GREAT compression if you REALLY know how to tune a car and 8:1 if you want to rev the snot out of it and run some killer boost ( hehehe the ones that know.... know... if you know what I mean. did that make sence? hehe )

Back on topic we go or lock

Thanx all and happy boosting
BM-

[Raven]

ok ok I'm bored out of my mind now thank everyone. :P

no one said i was going to build it for sure.. i wanted to build one.. and no one was telling me why i could/couldn't now people have thanks have a wonderful day.

another note Nick.. you say you read books and theres this Manual CD.. i've never seen this CD before and where do you find all these wonderful books? no book store around here has any.. Turbo Mag? all i ever read in there are hondas so thats useless to me it's not the same block.

anywho. thanks for the Critisism. and goobly goop on whats what


oh and my shift knob? you're Jealous ;)

[Rdy2race]

NICK NO!!!!! DON'T

What the point of that post was to "erk" the ones that helped I am sure it did. Don't expect help from the others. They gave reason you need to re read them

Now about the books. LOOK TO THE LEFT!!! TWO BOOKS FROM AMAZON ABOUT TURBOCHARGING!! WOW!!!

this is where you learn, Not the ad funded, slanted magz,

This along with asking the Q's in the right mannor. You have to understand that there is a expected amount of knowlage in this form and some have it and some are learning it. Just go slow and be sure to ask a simple "Why" when needed. just like a 5 year old that all that they say is "why?" is how you get answers.

Things like theory, general knowlage of a motor and so on are standard. givens that the people that are answering in here expect you to know and if you put it nicely they will explain why.

I think you ruffled some feathers with some people and this is why they were a bit snippy. I do agree that is why i jumped in to cool it off if you will.

I think the points were made loud and clear but not "tech" enough but I think that the post were made a bit more "no Tech" so that it would be easy to understand. You don't want Toast to go in the making of the atom of Alch fuels :D

lets keep it all nice ok

Thanx
BM-

[Nick 92 TSi AWD]

Sorry Bill ;)

Originally posted by Toast
If you really want to know that badly, I suggest you head down to the nearest university level science library and start reading. [/B]

[Tevenor]

What you are really looking for is Effective Compression Ratio, not just your static. Thats the end result of the boost pressure combined with the piston compression ratio to give you your final Effective Compression Ratio. So when verserv says 4 psi, he means the boost level figured with your static compression ratio based on identical setups. Ah hell, here is the formula that I use. (Guys correct me if I go astray).

Effective Compression Ratio = Static Compression Ratio x ( 1 + boost/14.7 )^1/2

Now lets say, on race gas and 7.8:1 pistons, someone is running 30 psi with no detonation(just assume it). That gives us an effective compression ratio of ~13.6:1.

ECR = 7.8 x (1 + 30/14.7)^1/2 = ~13.6

Now if you are at all mathematically inclined, you will see a problem with using 14:1 SCR pistons (if you know any algebra you will see the problem the minute you look at the formula above). If you feed the numbers through you will get a negative Boost level, which means on this car, you couldn't run any boost. Why no boost? See below.

Originally posted by Raven
Also higher compression means you can only run race fuel (110+). otherwise you get bad problems. (not sure what exactly) and if i could get 14-1 compression i could run alcohol safely.

The thing you are not sure on is detonation hence all the comments in this thread. The reason ECR is important is because if a car is running the ragged edge of detonation @ 30 psi, the same car with higher SCR pistons will need to run less psi or go over that ragged edge. Or if you lower your SCR, then you can run more psi and still be on the ragged edge.

Originally posted by Raven
if i could get 14-1 compression i could run alcohol safely. and have lots more power that way. now what my Question is, Has anyone tried this yet? or anthing simular?

Now comes the big issue. To run even just 4 psi of boost on the same car above that is running 30psi on 116 octane race gas, you need to seriously increase your cooling capacity over and above the massive cooling that a 30psi car already has. Otherwise you will blow your engine. Now maybe you can cool that 4 psi with a huge "side of a barn" intercooler, or alcohol injection, or no2, or any other methods of cooling the air charge so radically that you can pull back from the edge of detonation. But its a lot of research and time and failures just to go as fast as a 7.8:1 SCR piston car @ 30psi. In fact, because hp is really how much air you can flow through an engine system, even if you got 4 psi with 14:1's, the example car is still going to flow more and still going to make more hp (ignoring the addition of no2).

Now it is no where near as simple as I make it sound but hopefully you will get the idea as to why a 14:1 compression piston is best left to N/A engines or engines you only plan on running once.

Toast, nick, Bill....correct me if I am wrong here.

-Sean

[verserv]

yea the 4 psi was the estimate of what you would be capable of running as boost on such high compression which causes the resulted higher compression. check out ray hall's turbocharging for an ide of these calculation. http://www.turbofast.com.au/

[Rdy2race]

KIck ass Sean. Thank you for that post i think it cleared the air in here a bit

Now off topic. I see that you in NY or use a sig of a NY plate. I am also in NY to. Just woundering where from and NYC dsm is have a meeting on this sunday in upstate NY at the Auto X in the Palisades Mall then going to D&B for games food and what else?????
BEER!!

:D

Hope you can make in directions below all are welcome this is not "just for the members" it's fun for all.

http://www.turbologic.com/turbonyccdsm/palisades.html

[Tevenor]

See. You downstaters are funny. You think Palisades is 'upstate'. That makes me laugh.

I am in Rochester, probably a good 6-7 hours from West Nyack which means I would half to leave at 2 AM cuz if I have driving that far, damn skippy I am racing. :)

Hell Toronto is only 3 hours away. :) Thanks for the invite though.

How are the NYC guys getting to the SO? Thruway? Or taking 80 across?

[Edited by Tevenor on 07-11-2001 at 04:50 PM]