Motor Rebuild – (hot-to-trot)

[Paul.P]

[quote="LotusM100"[/quote]Well thanks, this thread has no more meaning to me due to the personal attack I will go on without sharing[/quote]

LotusM100, i can fully understand you being upset, but i don't think giving up on this thread is the answer. Although i have not posted on this one before, i have been following it with interest, as i'm sure others have. What i'm saying is there's a lot of interest in your engine rebuild, & it would be such a shame to stop it now, but i respect your wishes !

[Dico]

Yeah, as above!

Plus it saves me doing any homework

Get back on track Doc!

[Ashaman]

Dude...what is your deal? Do you want everyone to shout out how much they love you; please bring back your ball so they can finish the game? "Well, 'cause Asha'man didn't agree and he made me mad I'll show them all!" - Is that it?

Once again you must continue on ranting after I tried to end this as best as I knew how. You know what? Nobody even did anything to you. You are the one who originally started getting insulting without reason by trying to discredit my opinions with your nonsense about how I just out to poop on your thread and by juvenile name calling.

This started because I said I was doubtful and didn't agree, and asked about the reasoning behind it. Nobody "attacked" you before you first "attacked." What is even worse, you then shamelessly go back editing your past posts to try to make the whole thing make sense, it is just ridiculous.

I do not personally care much about any of it. You can finish, or not finish. You can spend the day with your family, or throw your engine in the garbage if you wish. I imagine though that others DO find it informative and would like to see you finish so...why exactly does it make you happy to try and punish them? Doesn't it seem just a little silly?

I am just a guy on the messagboard. I do not say who can post, or what they can post, get a grip.

[Doc Fizzix]

You are the one who originally started getting insulting without reason by trying to discredit my opinions with your nonsense about how I just out to poop on your thread and by juvenile name calling.

I totally think you have misread or are miss-reading a lot more into my posting than what I am saying, I bet that if you go back and look at them you will see that I was only trying to explain not "discredit" or "attack" you, I was only trying to explain in an informational way so the information could be understood and used by other since I was assuming others might have the same misconception. And from reading your original posting and your second follow-up I still believe that you might not be fully seeing the concept of boost pressure on the backside of the valves but I am not attacking you for it, I was only trying to explain it, I am sorry you see my explanation as an attack, I did not mean it that way. Please notice that I used "smilies" to show that I did not mean any harm. I only "pocked" a little fun at you for saying you were "pooping", I was not using it in a bad way. Please go back an look at my posting and I bet if you really read it you will see I was only trying to inform. You did take my words out of context and I did use the "evil smiley" but I would only ask that if you are going to disagree that you do not take other peoples words or change wording to suggest I said something I did not.

[Ashaman]

I get it. It is fine. I know what you were saying.

As far as I am concerned, the mods can delete all this nonsense as it is nonproductive. That way the thread can be back to its intended purpose.

I have no big problem with you at any rate.

[john]

couple things-

1- stock flywheel- i've sent my stock flywheel to ACT (very reputable clutch company in the USA) to get it lightnened (they do this often for the DSMs) and the guys there told me that
a) the flywheel is very light for being stock and,
b) removing any material would be risky, considering there isn't much to remove

2- valve springs- valve float does occur on our engines around 30psi-- below that? who knows, most people that have pushed above 20 go to 30 but if you're buliding up a motor and revving up to 9k and pushing any amount of serious boost, you may as well get some valve springs, too people have used 70 and 100psi valve springs on our motors..

personally, i'm going to keep the stock flywheel-- AWD likes heavier flywheels,, and trying to source some 100lb valve springs so i can push 30psi and a 100 shot of nitrous

R&D is too bling bling for my blood i can get ferrera's for bout $300 or so, but still too much.. there *should* be another option, if i can figure out which bike, that'll go for $200.. so we'll see!

and oh, Macs are #1

[Exbury]

Hey, I hope you still carry on posting on here, I have an Elan M100 and a Piazza and some of this information has been really useful even if it just fills up my brain with more and more car information!

However at some stage I may decide to rip the engine out and rebuild it to get better bhp and to freshen it up so all this information with really clear pictures was very useful.

I admit all the work is coming out from your end and it does take a lot of effort to photograph and then publish and explain stuff, after all, 1/2 the time on any rebuild I just want to get the rebuild done, stuff taking pictures as it slows me down. unfortunately I can therefore never give back the amount of information that you are giving back to the pursuit of knowledge about the Elan M100.

As you say, its mostly your or your rebuilders opinion, but that is very valuable in its own right. Please share, pretty please!

[Doc Fizzix]

The headwork has bee completed and the head is getting put back together. The valve seats were cut with a 30 – 45 – 60. The 45s were cut with the following contact widths that is different from the manual:

Intake: 1.3 mm (manual says 1.5 mm)
Exhaust: 1.5 mm (manual says 1.3 mm)

We have switched the two cuts, my tech believes the exhaust side will be getting much hotter with the increase in boost so we feels this cut will work better. With the intake seat, he feels we will get a little better flow with the cut starting on the small side.

My tech believes we will get much better air flow from the cuts we used on the valve seats, time will tell


Note: If it was not for all the "ink" on the bottom of the head, it would look as if the head just came from the factory

The intake and exhaust ports were cleaned and polished but not ported. I did not want to risk screwing up by removing too much material or having a mismatch in flow from port-to-port. The ports on the my stock Isuzu head really needed to be cleaned up, there were a lot of casting seams that were not cleaned up and the bend in the port right before the valve was way to sharp so we did round it off and we feel this will help a little with the air flow but our work was not as drastic as enlarging the whole port.


Description: Intake ports with the casting marks removed

I wish I had taken a before and after photo of the ports, they really looked horrible before we cleaned them up. Not pictured, but the ports were polished with a dermal and a polishing wheel, almost to a mirror finish.


Description: Intake ports showing a "smoother" transition at the elbow

Hard to see from this picture, but there was a very bad "edge" at the elbow of the port as the port points down towards the valve, we feel very confident that this would effect the flow of air so all "sharp" elbows were sanded down using a dermal. Now the ports feel so smooth and I am sure the air will be a lot happier flowing into the cylinders




Again, we did not try to change the size of the ports, we only tried to clean-up the casting marks and smooth the "sharp" turns. If you want information on porting, try this link: http://www.robietherobot.com/storm/geo_ ... orting.htm

[Doc Fizzix]

couple things-

1- stock flywheel- i've sent my stock flywheel to ACT (very reputable clutch company in the USA) to get it lightnened (they do this often for the DSMs) and the guys there told me that
a) the flywheel is very light for being stock and,
b) removing any material would be risky, considering there isn't much to remove

personally, i'm going to keep the stock flywheel-- AWD likes heavier flywheels,, and trying to source some 100lb valve springs so i can push 30psi and a 100 shot of nitrous

Thanks so much for your input John

I got my Flywheel today and it is very light Maybe too light!

To say the least, after the discussions as of late on this thread I was having second thoughts but today I did call Fidanza again (I am sure they are sick of me) and they feel that it is perfect for my application and then they said that they have sold a few to Dave Bean so I decided to call them up and get their throughts. Who ever I was talking with on the phone had very positive things to say about the flywheel upgrade and he recomended it. It was about the same time I thought to make sure we were talking about the M100, just as I thought, he was talking about the old Elans Oh well, he still said that it should be fine for what I am doing but he had not put one in any new Elans. I have read that the stock flywheel is perfect for the Isuzu AWD cars and you should not use a lighter flywheel with those cars. I am goinng to do my calcualtion on the change in rotational inertia over thhe following days just to actually see how much of a change there really is.

[F1 LOTUS]

Looking good
Did you have the manifold / ports matched such that the flow has no steps in the wrong direction?
A wider exh seat width is desirable for heat transfer(valve cooling), the inlets could even go down to 1mm.
Are you going to make an insulating gasket to reduce heat transfer into the intake manifold / plenum?
Extrude honing the plenum is probably worthwhile too?

[Doc Fizzix]

Brian

Good stuff! Thanks, I will need to talk with your some more.

I did forget to mention that we "opened-up" the valve seats a little more (made them larger), not sure the exact size, I will check with my mechanic but he said the stock valves had ample diameter to work with so the seats could be made a little wider without problem.

I was planning on shipping stuff off to Extrude Hone, but as we got going on the project there were things we just forgot to do. I can still sent of the plenum I guess

[Doug]

Nice project -- thanks for the pics and info -- keep up the fun . . .

[F1 LOTUS]

Just looking at this shot, there appears to be a shadow around the port which may be a mis-match or maybe it's just a mark left by the gasket?...This could really hurt gas flow


Most of the flow through an inlet port shoots straight across the back of the valve head roughly along the axis of the ports 'straight' section, so if you look down the port from the plenum side you'll get a good idea of surfaces that are likely to obstruct the incoming column of air. If you have a valve in when you look down there, open it gradually and you'll soon see if the head is masked significantly during the early phase of lift i.e. the valve is 'pocketed' and the combustion chamber area needs relieving in that area?

[Doc Fizzix]

Brian

I do not think I am following you so please forgive me, can you edit my picture in photoshop to show me what you are talking about? I can take some more pics if that would help? What angle would work best for a picture?

It sounds like you have some very important information here and I just need to figure out what you are saying

UPDATE ---

I think I am starting to follow your thinking. I see the small "color" difference around the port. I will have to line-up the head and the injector housing in order to check the fit. I will also have the check the gasket to make sure it does not obstruct the air flow OR cause an empty gap between the two parts.

Is this what you are talking about, or am I still not there yet?

[F1 LOTUS]

I guess what I'm trying to say is hold the port up to a light and try to look straight through the head from port entry to combustion chamber and you'll get an approximate idea of where the incoming charge is heading for?
With the valve in place it could be that the valve needs lifting several mm before you can see through due to valve masking? This sort of thing and the port matching is usually a safe bet in lieu of a flow bench

[Doc Fizzix]

Brian,

GOT YA

I will check tomorrow the fit between the two parts. Also, I checked the gasket and I might want to make a new one that has a better fit than the factory gasket, the fit is poor. I will take a picture and post tomorrow. Thanks bud

[Sy V]

I have studied the latter posts on this thread and I'm tempted to remove a few of the more 'derisory' comments. However there now appears to have been an agreement to disagree between the protagonists and, if harmony or mutual acceptance prevails, I'll do no more than continue to monitor the progress (here and in other threads).

Please bury the hatchets here guys, Doug and I don't like to have to take sides in these sort of disputes - they only detract from an otherwise harmonious and informative forum. We have enough 'outside knockers' on other boards, who I am sure, take no little pleasure in watching such fractious disputes.

Thanks

Sy

[Doc Fizzix]

Brian

Check this pic out! I see what you are talking about, the ports do not line up There is a step and blockage on both parts

I will definitely have to deal with this issue, thanks so much for brining it to my attention

[F1 LOTUS]

It's impractical to create and maintain a perfect transistion between the mating parts, so it's better to err on a slightly oversize mismatch (down step?) as the air goes downstream rather than risk having a small step-up that will 'trip' the air flow

Depending upon how much the parts can float around on the studs / fasteners before being tightened you may want to dowel the parts so their alignment is consistant before you start grinding material away?

[F1 LOTUS]

Here's an Autospeed article (the free bit ) about manifold insulators. It could be worth knocking a bunch of these out seeing that you're going through the exercise first?

http://autospeed.drive.com.au/cms/A_0401/article.html