Hi all,
Well after pulling the engine several weeks ago and asking retarded questions about push rod tubes, and oil geysers, I done n pulled the cylinder head off of #3 and #4. Having done this I was finally able to learn some things.

1. My cylinders are 96mm in dia and 76mm stroke, (I get 2.2L) Yeah!

2. My engine doesn't look like the prestine engines I see on all the Discovery Channel TV shows like Rides and Overhaulin.

So my questions to those who know.

1) Is it normal to have all this black cryosote (sp?) looking stuff all over the pistons and valves?

2) Should I just put this thing back together and quietly walk away and call the engine toast? or should I clean all the crude off and try and put it back together?

3) My compression numbers are:
Cyl #1 100
Cyl #2 85
Cyl #3 100
Cyl #4 75


4) Is this engine worth fix'n??

Piston #3 has a gash in it.

Cyl Head for #3 & 4

See all the crap on the valves is this normal?

Looks like any engine I have ever taken apart.

That gash in the piston is where the valve has tapped it in the past. It also appears that you have 48x38 valves (I can tell by the spacing of the seats)

That compression ratio is really BAAAAD. Should be like 180 or so if somebody actually calculated the compression ratio correctly while assembling the engine.


B

I'm also surprised to see head gaskets.


B

yupp, 96 means you got a 2056, valves are bigger than stock.
this *does* look like a keeper!

the crud is not too bad and can be cleaned easily.
the compression is *bad*. my engine has 150-160 on all 4.
nothing a set of new rings couldn't fix.

big valves and big pistons are guud!
Andy

No waaay...run away.
I'll do you a favor and send you a box, return postage paid, and I'll dispose of that horrible time bomb correctly. Dont take a chance....just hand it over.
I'll really be a nice guy and send you my perfect 1.8L screamer strapped to a pallet, just strap your old cursed engine in place on the pallet and install your new reliable engine..

Bob O


I took my 912 engine apart after 450 miles on a fresh rebuild and thats about what it looked like in the chamber.
Get new rings and new lower end bearings etc...what you care about is the condition of the journals on the crank. Have it chek'd (magnafluxed / mic'd / nitrided?)
new rings and bearings...new lifters if you're a spoiled rich kid.
Or if you're me run your fingernail across the journals on the crank, ANY feeling other than perfectly smooth?
No?
Put it Back together - Drive.

Rering the pistons rehone the cylinders and run it. What's it got feeding it? Dual webers?

Andy, he's got a 78 stroke so it really is a 2.2, not a 2056. Stoke 2 liter stroke is 71.

Bostonmeche, if you didn't fill in your location on purpose that's cool, but if you forgot or didn't realize then it's nice to know where are friends are located.

So I think the general concensus is to:
1. Clean everything up (hot tank?)
2. Scrap all the crude off
3. Hone the cylinders
4. Put new rings on the pistons

markd,
The engine is fed by dual Dellorto 40's and even has anodized blue roller rockers. I actually have a 76mm stroke, though I have to admit, I hear almost no one talk about using a 76mm stroke, usually, 71 or 78. I'm starting to wonder if I measured wrong. BTW I added my location.

Brad,
Are 48x38 valves a good thing, bad thing, or just something to know? I'm still too green to understand what that implies, especially since I have no idea what is stock.
Also are head gaskets bad in this case? Should I replace them or just leave them out (the edges of the gaskets are cut up)? If I throw them out what keeps it from leaking (not that the gaskets did either)? If I leave them out, it will affect my compression correct? You mentioned compression not being calculated correctly, is that because you assumed the rings were good and the #s were bad or was there something else that led you to believe this.

Should I grind the valves too? I don't even know exactly what that means. What parts of them am I grinding?

Are these things DIY operations (ie, honing cylinders, grinding valves)? Or do I need to find someone in the Boston, MA area to do it? Also, when I put new rings on how do I know what size to order? Do I base the size on Cylinder dia or by Piston groove?

I just looked on pelican for rings $50/cylinder. Is that normal? I mean these are just flat sheet metal parts aren't they?

If you couldn't tell, the only engine I ever took apart was a Briggs & Stratton back in high school. So I appreciate all time you guys take to reply to what must seem to be pretty mundane if not common knowledge type of questions.

Wow did I write a lot! If you actually got through it all

let me try to be diplomatic... you are on the verge of being in WAY over your head.
take it slow, and let people help you. but you DO need to get some more background and do some basic research. if you don't have a Haynes manual - go get one. read all through the engine overhaul procedures - a couple of times - some things that don't make sense the first time will begin to as you become more familiar with the terminology.

i'm a little out of my element in dealing with T-IV's but i have learned a lot from what's been posted on this site (and others). ship off the heads to someone for a valve job. it is NOT a DIY project, even with stock parts. get some suggestions from people here who have head specialists they can trust. RIMCO is one, for street engines. there are a FEW reliable headflow performance shops if you want more. since there are but a few, they usually have backlogs, and they aren't cheap; tradeoffs...

rings are NOT just sheet metal, and you have to get EXACTLY the right size (diameter and thickness - to the 0.0001" and no i didn't use too many zeroes.) even then you'll have to fit them to your EXACT cylinder dimensions. if you haven't honed cylinders before you might consider sending those out too - it's easy to do wrong. (but the beauty of the T-IV engine is that it's pretty tolerant of minor inconsistencies - it was, after all, a production-line engine. but it will run BETTER if everything's matched.

not only is your compression pretty low, i'd want to know why it's so much lower on one side than the other. sloppy assembly could account for it but it could also be something deeper...

you're on the Internet - have a look through the Pelican tech articles and do some research on valve jobs. BUT - there is LOTS of bad information and misinformation out there - and all it takes to make it LOOK plausible is to have a nice website. come back here for The Straight Scoop - there are more experienced T-IV builders here than just about anywhere - with the probable exception of the ShopTalkForum board - and go read everything over there, too.

some of the parts are expensive and can be damaged by inexperienced handling.

you're doing the right thing coming here and asking questions, but IMO you need to do a little more research to make sure you're asking the right questions and in a position to really understand the responses.

stick with it, take it slow, get answers and suggestions, and you'll be fine.

Good advice. I agree 100%.

Tom Wilsons book is a good read as well.

Has the engine case been machined to give the rod clearence? you have to create clearence if it is a 78 stroke I dont know if it is a 76 stroke. I wnted to build mine with a 76.4 stroke but couldn't get the crank, so I went with a 78.4. I would be interested in your engine if you decide to sell it, but properly done with the right cam and lifters it should make a great engine.

Bernie

78 doesn't need machining (or very slight), so 76 definitely won't. Plus it was running before, so it's not a problem on this engine.

Does squirting oil in the cylinder when doing a compression check work on type IVs. I never hear of anyone doing this on type IVs.

On my old bmw 320i engine it was recommended that one do a regular compression check and then redo it after squirting some oil into the cylindner. The theory is that if the compression reads higher after a squirt of oil then you know that you're loosing compression through the rings and not the valves.

The oil will sit on the bottom of the cylinder and not do much. The BMW has relatively vertical cylinders to oil will distribute evenly around the ring and help seal.

it's not as effective on flat engines, which is why a compression test is typically followed by a leakdown test to determine the extent of the leaksge and - by listening to the escaping air you can tell the location of the leakage.

oops, my bad, guess i should have read the "76 stroke" part ...

Andy

I appreciate all the input.

I am just trying to keep this engine from gooing oil all over the ground and since the engine is out, perhaps pick up some extra lost hp.

What is the cheapest way to put the engine back together and still get some hp back. Could I just hone the cylinders and put in new piston rings? I will definitely buy the Tom Wilson book. Perhaps that will answer a lot of my why and what if questions. The Haynes manual is good for seperating things and putting them back together but does not really explain the trade offs of making certain decisions.

This engine is only supposed to stick around until I have the funds, time, and experience to do a -6 cyl. I don't want to spend a bunch of money on this engine only to sell it to someone for 1/4 of the price. The flip side is that I don't want to grenade the engine because I think there are people out there that would probably be willing to buy some or all of it. Every $1 saved is a $1 spent on the 6

Hone and rering should get you back into "decent" territory and should give you a few more years. Of course, that assumes everything else is setup okay. If it was running before you should be able to rering and hone and bring the compression back up. You could have the heads checked out by a machine shop and have the valves reground and possibly the guides replaced. That should keep the heads happy.

I realize that this question is really loaded but....

How much does a head job with a valve regrind cost? As I start asking around I want to know when I'm getting screwed.

Also, if I re-ring the pistons, do I still have to split the case? I thought I could just pull the cylinders and slip the pistons in from the back. An aquaintance told me that it won't work like that but couldn't explain to me why.

You don't have to split the case to install pistons and cylinders, they detach and reattach just to the rods.

Head work depends on the work that hasta be done.

Geoff

if you have inspected the heads and found no cracks, call RIMCO and ask for a quote on a basic valve job. tell them your valve sizes but presume they'll be okay with just a freshening and will not require replacement. i'd replace the springs on principle but if they meet spec you might be able to slide on that.

you don't need to split the case, but you WILL need a 'take-apart' ring compressor. there are a few styles, i donno what's the flavor of the day for 96mm.

if you are removing the pistons, it's my recommendation that you remove and recondition the rods, and replace the rod bearings. rod bearings have a hard life in our engines and this, too, can be done without splitting the case. lots of people don't do this, so it's clearly optional, but it's pretty normal in 911-land for people to cheap out on top-end work, doing a valve job and re-ring, only to lose a rod big-end bearing a few thousand miles later. your call.

I've had luck using a non take-apart ring compressor. If you compress the rings and slide the piston in just up to the top of the wrist pin hole while it's off the engine, you can remove the ring compressor and then attach the piston to the rod and finish sliding the cylinder down into place.

applescotty

OK, I'll be putting an order into Pelican tonight that includes among other things Tom Wilsons book. In the mean time, I was hoping someone could tell me how to properly measure the piston rings and valves so that I can:

1. Order the piston rings

2. Tell someone like Rimco what I have for valves so I can get a quote.

I would like to get the car put back together soon so I can continue to enjoy it for the precious few good days we have in New England.

valves - measure the diameter of the head in mm. it doesn't have to be accurate to many decimal places, you just want them to be aware that you have non-stock stuff.

piston rings - i'd probably call the guys at EBS for those... the piston diameter you have. very carefully remove the rings from one piston - try not to break them because at some point it will be nice to compare end gaps ... v-e-r-y accurately measure the top compression ring, the 2nd compression ring, and the oil control ring thickness. PROBABLY they will be some even fractional number of mm. IMO - the guys at EBS are much more likely to be able to identify and source individual ring sets than Pelican. as much business as i do with Pelican, for engine hardparts, i go to EBS...

you will probably have some choices on ring type to make - Total Seal or not, for instance. my suggestion: describe your intended use to the guys at EBS and let them make a recommendation.

i've heard both praise and horror stories on Total Seal rings, so i suspect that means there are lots of variables at play.

Hey Bostonmeche,

I'm also located in Medford! I have a set of micrometers that I can lend you to measure the rings if you want. Email me rhcb914@yahoo.com if you are interested.

Tom Wilsons book is great! I have used it to build a few engines including the one in my 914, a 1911cc. Not an expert by any means but willing to help you out.

-Rob

The guy you need to talk to is Jake Raby. He posts a lot here and on the shoptalk type4rum. He reccommends Hastings rings, nothing else. However, since you have non-stock P&C set, you need to find out the manufacturer of the P&C set. Only then can you be sure to get the correct type rings for the pistons. They can vary in thickness, number and location of each type. When installing the rings, there are very specific ways to align the gaps. Get the Raby video on assembling a type 4 engine. You are going to need a lot of help on this project, so don't be afraid to ask lots of questions.

Rhcb914,
Thanks for the offer. I'll probably will take you up on the advice and help. I don't need any mics though. I have a nice digital verier and a qualified micrometer to get me by, hazards of imagineering work

Where you located? I'm two houses down from the big Kappy's (for those not in the know Kappy's is this gigantic liquor store, an anathema to the blue law toting puritans that had founded the state). You should come over sometime and view the carnage and have a beer or two. I'm a homebrewer and have a healthy stout that would kick your

ArtechnikA,
Again, thanks for all the advice! It is really appreciated.

Don't forget to buy a ring expander. You are lible to break the new ones, or scratch your pistons pulling the old ones out. Also, clean the
carbon up off the bottom of the ring groove. Also, Look really close for cracks in your heads, the 2.0 heads crack super easy. Good luck, and keep asking questions, that's what we are here for.

Bostonmeche,
You probably do not realize that you have one of the very good engine building groups just west of you. Contact Mike Seymour at Autocraft engines in Marlboro, Mass. Do not be afraid of the pricey quotes on their race engines. I'm sure they will be glad to advise you. However, remember, it is the peak of racing season and those demands will come first.
http://www.autocraftengines.com/
L. McC

I'm on the other end of the Fellsway. Up by wrights pond.

Love to swing by for a

Email me and we will get together.

Brad,
(Not that you didn't know) you were right on about the valves 48mm exhaust and 38mm intake.

Where are the likely places to find cracks in the heads? I'm looking near the spark plugs and near the valves and haven't found any yet. Not that I want any, I just want to make sure I'm looking in the right places especially since I remember someone saying 90% of cylinder heads have cracks.

Also, there seams to be a maching break out between the two valve seats in cylinder 4 (the right side of the first picture) I wouldn't think that this matters because it occurs outside the seating area. What do you guys think? Sorry about the crappy picture, I've been scrubbing the heads but it takes a bit longer than I thought to get all the carbon off.

Don't be too concerned about cracks near the valve seats. Here in Canada we rarely see them. Only in the deep south or California do they seem to crack readily. Glass bead or walnut shell blasting is good to clean the carbon from the heads.

I agree with the bead blasting comment, but my 2.0 heads were cracked majorly when I aquired the car. Cracked heads are usually a sign of a bigger problem, or a poor repair. It won't hurt looking.

Ambient air temps have very little to do with the temps that the heads ee. The heads in my cars run the same winter or summer, regardless.

What kills heads is improper tuning which makes heat, and drivers that use 5th gear when they should be in 4th.. slow fan speeds and more load on the engine builds heat in the heads like a maniac.

90% of the 2.0 heads that we see have cracks around the plug holes. Those are welded up, and 12mm plugs are installed to add strength to the chamber to prevent re-cracks from occuring.

Those 48x38 valves are far from an optimum 80% I/E ratio, guaranteed.... The intake port on the TIV already flows well out of the box, making it larger increases the demand for the exhaust to flow more to get the 80%.....

Huge intake valves, require cams with even more split duration on the exhaust to gain a combo that is efficient...

The largest intake valve we run is 44mm, and thats on a 2739cc engine... Its good for 239BHP, as a daily driver at 10:1!

Jake, are you trying to tell me my engine ain't as good as yours?

I ran a few numbers once you told me the 80% ratio rule... Who ever built my engine followed it to the "T" 38/48 = .79 Now I realize that this is probably not right ratio that you are refering too. I would have to guess that you are talking about the skirt circumference. In the industrial valve world, we usually try to correlate flow from the circumference of the valve * the height that the plug (i.e. the head valve) is away from the seat. The only issue is that that essentially is the same because the valve strokes are equal (are they?) and Pi cancels out. So now I'm really confused. Are you talking about valve area when you talk about the 80%?

BTW, I didn't know you could make large hp reliable daily drivers out of 4 bangers. I was seriously considering your 2270 engine except that it only puts out about 160hp. I was hoping for a reliable 200hp at the least and ideally something good for 250hp so I am looking to do the 3.2. By the way, I consider reliable to be 100k miles without a rebuild or anything major to fix. Since this car is just a 2-3xs a week driver I figure it would take me 10 yrs or more to get to 100k.