you sick, sick pervert :yawn:


i got a credit card limit increase... so naturally i'm going to run it right back up :D

Here's the plan so far:

Accurate Pistons $600.00 (or maybe not... rick?)
Accurate rings 58.75
NAPA Crank (PRR25300) 210.00
Summit Sealed Power Gasket kit (SLP-2601424) 74.39
AutoZone Melling Oil Pump (M167HVS) 53.99
Summit Cloyes Timing set (CLO-9-3127) 106.69
Accurate Timing tensioner 9.00
Summit Crane cam & lifters (CRN-753901 & CRN-9927812) 178.87
Summit Crane valve springs (CRN-99833-12) 52.39
Summit Sealed Power freeze plugs (SLP-3818084) 16.69
Summit Mopar pushrods (DCC-4529675) 16.39
Accurate head bolts 56.65
Flowkooler water pump (BRA-1747) 102.39

reusing stock 4.0L "long" con rods


sound good? any room for improvement? i've been doing my homework on NAXJA and on the strokers yahoo list, and this seems like it's going to work pretty well with a .030" over block and mild head work. Gotta keep the smog nazis happy too :rolleyes:

i'll post pics as I build this puppy up over the next several weeks (still waiting for the block to come back from the machine shop :P )

thanks-
Chuck
:hat:

What about a stock 258 Crank and rods? I *think* thats what I was going to do. If I remember, its the same crank, just longer stroke. It might save a little.

The crank Chuck is using is a 258 crank. The 258 crank is 3.9" stroke, and the 258 rods are 5.875" long. Stock 4.0L rods are 6.125" long, which makes the piston top higher than the deck at TDC. Thus, you need a custom piston with a higher pin location. Using stock 258 5.875" rods increases the quench hieght to 0.081" (I think 0.051" is stock on a 4.0), resulting in higher emissions, not as much power, higher fuel consumption, and prone to detonation. If the block is milled to restore the quench height to closer to stock, the combustion volume is decreased even further, resulting in close to 10:1 compression, requiring high octane fuel and ECU remapping. Hence, the custom piston which allows use of the longer 4.0 rods. It is possible to increase the combustion chamber volume to help reduce the CR, but this also costs money unless you are into cc-ing heads yourself and using a die grinder very very carefully. Thus, the real cost of the custom pistons is the difference in cost between purchasing stock 4.0 pistons and 258 rods, assuming you have good 4.0 rods to mount the custom pistons on:

Short 258 rods + stock 4.0 piston = $350

Custom pistons + reuse 4.0 rods = $550
Difference = $200

The longer 4.0 rod also results in a higher, more desirable rod ratio. This is not really a major concern in an engine with a redline of ~5,000 rpm, but what works on a race engine just makes a lower rpm engine last longer. Custom JE pistons are $550 a set, possibly lower if I buy more than one set. The machine shop I use would probably not feel good about ordering you pistons though Chuck unless they look at the block. They don't like doing things twice ;)

rick

what rick said :D i'm using a 258 crank, 242 rods, and custom pistons with a higher pin height. i haven't decked the block at all; assuming it was flat when I took it to the machine shop. if it's not, then it'll likely have .010 taken off. I'll likely shave the head (which is also getting rebuilt) a little, then use a thinner than stock head gasket to bump up the CR a bit. I'm looking at ~9.5:1 right now (actually more like 9.45:1 ;) ) throw in a mild cam with a little more lift & duration, and viola! that's my new engine.

also getting all new/reconditioned goodies- high volume water & oil pump, distributor, harmonic dampener, H.O. alternator, etc.

good stuff!

rick says don't get a high volume oil pump.
use a stock one!

Originally posted by sarah
rick says don't get a high volume oil pump.
use a stock one!

Why?:confused:

and we're under way...
http://www.trailbossoffroad.com/engine02.jpg

http://www.trailbossoffroad.com/engine06.jpg

the color is AMC blue :D since I took the pics, i got the crank and cam installed, and discovered that all but one of the mains are slightly bigger than spec, so now i'm waiting on the next undersize bearings :( the crank was 'reconditioned' and all journals were turned .010" smaller than factory. that, combined with the hone job at the machine shop, made the journals too big. the service manual says I can mix bearing sizes, so i'm going to use the .010" undersize on top, and .020" in the caps, tightening up clearance by .005", putting them all into spec.... hopefully :D

pistons are due to arrive on Tuesday, and the head's being rebuilt as we speak! yay ;)

:hat:

Originally posted by cbremer
the service manual says I can mix bearing sizes, so i'm going to use the .010" undersize on top, and .020" in the caps, tightening up clearance by .005", putting them all into spec.... hopefully :D


So the hole is out of round? That doesnt sound good. are you using plasti-gauge to check the clearence?

Originally posted by Dukes69
So the hole is out of round? That doesnt sound good. are you using plasti-gauge to check the clearence?

yup... used plastigage. i know what you mean about that method leaving the mains out of round... but the manual says it's OK :confused:

i'll try using all .020" bearings- maybe it'll be a little tight, but within spec. at least that way they'll all be round :D

Yeah, I'd try all the same bearings, just to see if they are in spec. I've never heard of using different size bearings top and bottom. Sounds eff'd up to me :eek: :confused: :P

Sounds bad to me also... I always thought bearings were matched to one another.

There was much debate and many posts in several forums a couple years ago when I built my 258 about hi-vol oil pumps and problems with everything from priming to life of the pump. I had a hi-vol pump the first time I rebuilt the 258 and I had priming problems for the first two oil changes. I put a stock pump in it after the second rebuild and then I had priming problems because I had the wrong oil pickup tube, but the pump was fine after correcting that problem.

Nice looking engine Chuck.

What bearing clearance are you shooting for in the swapping/mixing of oversizes? If they are all 0.002 - 0.0025, you are sittin in tall cotton... I wouldn't make them tighter. I think factory specs are a ridiculously tight 0.001-0.0015 or something. This is too tight in my opinion. The only difference you will see is in the oil pressure at idle. My mains are 0.0025" on the nose and I run 15-20 psi at idle, then it jumps up immediately off idle to 30-50 depending on rpm and temperature. If the lower oil pressure bothers you, just run 10W-50 oil. I get 20-25 psi at idle with the thick stuff. The larger bearing clearances help protect the bearings under high loads, particularly at low-medium rpm where harmonics and high torque can deform the crank slightly. This is particularly true of a high torque, low rpm six cylinder with inherent vibration issues like a stroker. These engines have a high rotating inertia, so once they are spun up to higher rpms the damper and flywheel actually do very little to smooth things out enough to where the bearing loads are more even, as is the case in most 4 and 8 cylinder engines where the rotating masses are in opposition during most of the crank cycle. This is where tight bearings can eat your lunch. One mishap at higher rpms and that 0.0015" will disappear very quickly and send metal flying. The more oil that flows between the bearing and the journal, the more heat transfer occurs between the metal surfaces. Of course, this is only true up to a point (I'm sure 0.05" clearances are not good), but if 0.0025 is good enough for a big block chevy on nitrous putting down 800 hp, it's good enough for me. Just my $0.02.

just one question... what the heck are you guys talking about???:confused: j/k:D man, I know so little about building engines.:yay:

that is a nice looking block you have there.. how is progress? did you resolve the bearing issues?:oink:

.020 undersize main bearings were delivered this week, and i'll be (re) installing the crank over the weekend.

got the head back from the machine shop too :) i suppose i'll give the ports a once-over with a Dremel too.

the FSM recommends .002" clearance, but .001-.0025" is acceptable. i was getting >.003" on all the mains (some as high as .004"). this is really all that I was waiting on... now I can really get crackin' on assembly :D



:hat:

p.s.: I just ordered this beauty:

http://home.earthlink.net/~cbremer/header.jpg

it's on backorder, but I'm pretty patient :yawn:

Originally posted by cbremer
.020 undersize main bearings were delivered this week, and i'll be (re) installing the crank over the weekend.

got the head back from the machine shop too :) i suppose i'll give the ports a once-over with a Dremel too.

the FSM recommends .002" clearance, but .001-.0025" is acceptable. i was getting >.003" on all the mains (some as high as .004"). this is really all that I was waiting on... now I can really get crackin' on assembly :D



:hat:

p.s.: I just ordered this beauty:

http://home.earthlink.net/~cbremer/header.jpg

it's on backorder, but I'm pretty patient :yawn:
BLING-BLING! :D
i hope all that bearing stuff works out for you... i'm no engine expert, but it seems a lot of measurements are off here.. and you KNOW about them, and are proceding. i hope it all goes well for you.:wave:

is that the MoPar header??? if so I hope you got a helluva deal on it.:eek: nice.:D

good news... the bearings worked out. all mains are within spec, so I started assembly today :D best I can guess is, I bought a 'remanufactured' crankshaft, which means they turned all the journals down .010", and tossed in a set of undersize bearings to match. problem was, i had the block machined, which included boring the mains, making them a bit big/loose. they must have removed .010", since it all worked out.

pics to follow....

brian, that is indeed the mopar performance/Mike Leach tri-Y header. more power! (insert Tim Allen grunt here) I got it from Summit racing for less than I found it anywhere else... but I have to wait a while :rolleyes: no hurry, since I have a ways to go on the engine itself.

:hat:

I hate to mention this now, but better late then never . . . I've built a couple engines, and when I do I always wash the block with soapy water and clean it real good, after is has been machined. I also run a tap in all the different holes, especially the mains and head bolt holes. This ensures proper torque. Easy and cheap insurance. The last thing you want is metal shavings in a new engine or a crank that breaks in half due to impropper torque:eek:

have fun!

:D

crap on you... good thing i did all that stuff :D (i did my homework ;) ) 14 head bolts and 14 main bolts- that took a while :D

1 turn in, 2 turns out, use cutting oil, all the way to the bottom of the hole, clean the hole with brake cleaner and blow it out with compressed air, clean & oil the tap for the next hole, repeat. 28 times. ugh.



:hat:

very good :D

finally more pics. now you can see why i'm know for my punctuality :D


pretty... (my preciousssss......)
http://trailbossoffroad.com/engine10.jpg

http://trailbossoffroad.com/engine14.jpg

http://trailbossoffroad.com/engine13.jpg

yeah.. um.. that's about it for now. i hope to get the pistons & rods installed and button up the bottom end this weekend- maybe even start on the top end. :yay:


:hat:

very nice chuck! You're doing a damn fine job. I cant wait to get your reaction when you stick it in there. :8

lookin good, chuck! keep a tally sheet so i know what this whole mess is costing ;). i am interested, but unsure what i am willing to spend on it. great looking progress there :wave:

Originally posted by Dukes69
I cant wait to get your reaction when you stick it in there. :8

that's what she said...:eek: :D :yay:

Originally posted by blkTJ
that's what she said...:eek: :D :yay:


HAHAHAHAHA....:P

Is that a stock distributor? Looks nice - make sure you lube the snot out of everything - moly paste on the rod bolts also to ensure even torque. I like Childs and Albert for the top end, it's kinda like sticky 40 weight.

yup, rebuilt stock. a rebuild was cheaper than replacing the electronic points thingie, so that's the way I went. also stock OEM cap/rotor, new OEM harmonic dampener.

how much more power do you get out of the stroked 4.0?

quick update- I fuXored one of the pistons while pressing the pin in :( so a replacement is on order (accurate was low on stock and didn't want to split a set, so mike ordered a single extra just for me :yay: ). also been working or port matching the intake manifold to the head and opening up the exhaust ports a bit. also smoothing the combustion chambers a little. slow going, but it's going :D

:hat:

p.s.: rick, about using lube on the bolts, how much less should I torque them to? i know the dry torque is different than wet torque... but how much? i.e.: 20% less?

thanks!

The torque values for the engine bolts are usually given in lubed condition (mains and rod bolts). You should be putting at least new rod bolts, if not main bolts, when you reassemble. Buy ARPs and they will come with specific instructions, otherwise it should say in the manual which lubricant to use (oil or moly paste) on the OEM bolts. I really need to get one of those mopar engine books... I think many of the differences are described. When I did my 258, I torqued the mains to the spec in the manual using oil. I used ARP rod bolts and they even came with their own fancy moly paste (it's the same stuff...)

Are you using stock fuel injectors Chuck? I am thinking of going with some 26 lb/hr LT1 or Accel injectors. That will keep them around 80% duty cycle. The stock 19 lb/hr injectors will probably only be good for about 240 hp before you hit lean run conditions at wide open throttle. I'm assuming your setup will make closer to 250-260 hp, which means you need 260 x 0.5 / (6 x 0.8) = 27 lb/hr. I think you could even go with 30 lb/hr, but I'm not enough of an EFI guru to know what the adverse effects of having a slightly large injector is... Although that would allow for future upgrades like, say, a Hesco aluminum head ;)

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=2476703967&category=33554
i got my injectors from this guy.. good price, and local pick up. in lakewood ;) see if he has what you need ;)

Thanks man. I saw those on ebay... the problem with his auctions is they are for V8s so you pay for 8 instead of 6... I found the Jeep injectors on their site here (http://www.fiveomotorsport.com/Injector_SetsJEEP.asp). I'm still not sure if 24 lb/hr is enough...

i found a good deal on ebay for a set of 26 lb/hr accel injectors, so i went with those. i felt that 24lb would probably run a little lean (or running too long a duty cycle), 30lb a bit rich. without looking, i bet erik's link is to 5-0 motorsport ;) i bought my stock 19 lb/hr replacement injectors from him (originals were leaky) and had them the next day- they're still running perfectly!

i've also seen (on ebay) some newer Delphi (GM?) fuel injectors that will supposedly fit bosch-type FI systems. don't know about those for sure- didn't want to be the one to find out that they don't work :D

Dino has good tips & tricks about how to fine-tune your flow rate by making an adjustable MAP sensor here: http://www.angelfire.com/my/fan/MAP_adjuster.html

his main site: http://www.jeep4.0performance.4mg.com/index.html

Originally posted by rick
Thanks man. I saw those on ebay... the problem with his auctions is they are for V8s so you pay for 8 instead of 6... I found the Jeep injectors on their site here (http://www.fiveomotorsport.com/Injector_SetsJEEP.asp). I'm still not sure if 24 lb/hr is enough...
just call, or email him, and he will sell you what you need. ;):wave:

Yes, he has a good site for stroker info. I think the MAP adjuster setup he made is a little crude, so I am thinking of maybe putting it in a nicer box or something from Radio Shack to keep it a little safer. I'll post pics when I get to that point.

I just noticed this thread...
I built my own stroker 2.5 years ago.
I used the 258 crank and rods, but I had the 258 crank offset ground a bit to help with the quench. I have done a lot of research on this and it is now generally accepted that the quench isnt nearly as important as the compression ratio when trying to control spark knock.
That said.. I have always run premium in the stroker, but I noticed that when I was on the east coast I could buy 93 octane premium and it was a lot better mix than the 91 octan california crap. I started to get a little spark knock out here, so I built an adjustable MAP sensor and it eliminated it....though at the cost of some MPG.

My stroker is a 97 OBDII stroker though... 24# injectors from the factory.. I'm sure this helps.. I also have the desireable coated pistons from the factory. I had to cut the tab off the distributer and index the distributer a bit for the computer to pick up the signal. I also had to space out the bottom skirt plate thingy with some washers so the bottom of the rods didn't hit.... But my stroker only had 19000 miles on the block when I broke a rod.. I didnt even bore it, and the ONLY changes I made were the crank and rods.( OE pistons)Oh, I have a very low RPM cam in it too.. probably too mild actually, but I have incredible throtle responce.

If I was going to build another stroker ( I am going to) I'm gunna deck the block and dish some silvolite pistons with the 258 crank and rods again. I think the 24" injectors are enough for a rock crawling stroker with a mild cam.. If I were turning serious RPM I'd get bigger, but I think that the piston speed in a stroker is too high to expect the engine to last at redline all the time.
The only thing I really dont like is using the stock rods. I have broken 2 connecting rods. If I were gunna spend $$$ on aftermarket internals I'd buy rods first.

my stroker runs very very strong.. I really notice it when I get into my wifes 2000 tj and drive her 4.0.. I have so much more power than she does. Before the MAP sensor, I got about the same milage as before I stroked it. My stroker has 11000 miles on it, and many many of those miles are wheeling and/or idling at 2800 rpm running the OBA or welder.

If you didn't dish the pistons and you used 258 rods, isn't the compression ratio approaching 9.7:1? Maybe this higher compression is part of the rod failure? I guess that kind of increase should not cause a rod to fail, but maybe related? Did you have detonation problems?

I broke the rod when the engine was stock. I have not had any problems since I built the stroker.
CR is about 9.6/1 or so... not really that bad.

as to detonation problems... um.. I talked about that in the previuos post...

Duh, sorry... I guess I was in a hurry when I replied. Hmmmm, stock and broken rod? That beats the heck outta me. I have never heard of broken rods in either the 4.0 or 258. There's a first for everything...

thats actually the 4th one I have seen, and every time it was the number 6.

I just read this thread and wanted to comment on the machining issue.When a block is align bored the main caps are removed and the bottoms cut on a cap grinder.They are reinstalled on the block and it is then machined to factory OEm specs.This actually moves the crank up in the block slightly but that is how it is done.
Like wise when a rod is rebuilt the bolts are removed,the cap and rod shaved and bolted back together(preferably with new bolts).The hole is now smaller and obviously out of round.It is then honed to the correct diameter and checked for size and roundness.This process actually slightly shortens each rod.
Just adding my 2 cents...

thanks! you learn something new every day :D

as a small update- i've got the bottom end done (just have to make a little clearance for the oil pump and bolt on the oil pan) and i'm almost done with the long, painful process of porting the head and intake. not so much to enlarge, but more along the lines of port matching, at least on the intake. the exhaust is getting opened up a bit to take advantage of the header :)

with any luck... another 4 to 6 weeks :D just because i'm a lazy bastid

Sounds Good!My son and I are going to rebuild the '82 258 in his '89 YJ(he now wants to paint it AMC blue..LOL).It's going to be a basic rebuild with a 4.0 head on it.
Keep this thread going we want to see your finished product! :)

even if it doesn't run, at least it looks good :D

http://trailbossoffroad.com/engine005.jpg

http://trailbossoffroad.com/engine006.jpg

http://trailbossoffroad.com/engine007.jpg

going to indiana over this weekend, so I hope to work on swapping it in next weekend. maybe it'll even start :D :no:

it sure is perty :wave:

Looks fast anyways... I think that is the last 4.2L crank core in the US. Napa didn't have one when I first tried to order it (right after you did Chuck), and I have been through 3 places that say "yeah, sure we have one of those..." only to find out after they actually look on the shelf that they are out of them. I have started expanding my search...my father is looking for one in the engine scrap yards of good ole Detroit...

My son just bought a 4.2 crank for his YJ at Advance Auto.$173.00-his old crank was worth $20.00 as a core.It's been turned .020 on both rod and main journals.

Looks fast anyways... I think that is the last 4.2L crank core in the US. Napa didn't have one when I first tried to order it (right after you did Chuck), and I have been through 3 places that say "yeah, sure we have one of those..." only to find out after they actually look on the shelf that they are out of them. I have started expanding my search...my father is looking for one in the engine scrap yards of good ole Detroit...

Rick I have 4.2 long block in the Garage. It'll cost a "Howdy" from ya. If you want the crank just say " Yea Ha". :wave:

How about "Yeeee hawww"? Can I say yeee haw instead? I'll take it - heck, i'll even pull it myself.... we'll be in touch.

alrighty then... theis is getting serious :D

before:

http://trailbossoffroad.com/install01.jpg

making a little room to work:

http://trailbossoffroad.com/install02.jpg

OUT WITH YA!

http://trailbossoffroad.com/install03.jpg

seems to me that something's missing?

http://trailbossoffroad.com/install05.jpg

much better :)

http://trailbossoffroad.com/install06.jpg

finish up the wiring, new radiator & hoses, other odds & ends and (hopefully) firing it up tomorrow

WOW!

Thats purty Chuck!

Good luck with the install:)

Tam:)

what a mess!!

I mean . . . LOOKIN GOOD!! :D

She looks soooo SWEET!!!Wish I could be ther to hear her fire up for the first time!Actually I wish it was in my CJ!

Boo now we cant race fair. Better hook up the nos........


Looks good Chucky.

Looks nice, you need some help breaking in the cam? I'll hold the throttle open for you ;). That's the fun part...2,000 rpm for 30 minutes. The neighbors love that, especially if you do it at about midnight or so on a school night without the exhaust hooked up...

This is the pic I was looking for... Now I know for sure what these brackets are for on this junkyard engine I have - I thought they were XJ. I guess I need to keep scouring ebay for a wrangler a/c bracket. Damn I wish I paid more attention to what the heck I buy...

well it fired up on the first try :D :D the directions that came with the cam said to run it for 20 minutes... which I did, of course. I haven't taken it for a spin yet since I still have a few minor things to do: bolt down the airbox, connect the ground strap, top off the transmission fluid (lost 4 or 5 quarts when I disco'ed the tranny cooler lines and removed the torque convertor). It starts after turning over 2 or 3 times and runs & revs like nobody's business. Oil pressure is right at 40 PSI cold. I can't wait to take it for a spin tomorrow :D Not bad for a first-time engine builder ;)

This thread has been totally fascinating for me even though I hardly understand it :) Any good books out there about engines that can help me to at least understand what everyone is talking about?

woohoo! it's done... it runs... the distributor was one tooth off so it knocked and backfired a bit, especially under load. reindexed the dist. and all is well :D :D it's got a very slight ping in 4th gear so i might need to invest in octane booster (or 89 octane gas).

nagal, in the simplest terms, stroking an engine is a method of rebuilding using non-stock parts to increase the stroke (the distance the piston travels up & down the cylinder). in the case of the Jeep 4.0L, there are several ways to do this, depending on how much you want to spend ;) i used a crankshaft from a 4.2L Jeep engine, 4.0L connecting rods, and custom-made pistons. I also bored the block over a bit, making the diameter of the cylinder a bit larger as well. my engine is now about 4.6L displacement. tons of fun :D

woohoo! it's done... it runs... the distributor was one tooth off so it knocked and backfired a bit, especially under load. reindexed the dist. and all is well :D :D it's got a very slight ping in 4th gear so i might need to invest in octane booster (or 89 octane gas).



Nice work chuck! Maybe try some 91 octane! :D what did your compression ratio come out to be?

Nice work chuck! Maybe try some 91 octane! :D what did your compression ratio come out to be?


best i can figure is somewhere around 9.4 or 9.5:1. a bit higher than i had hoped, but the machine shop did say that the deck wasn't exactly flat :eek:

Thanks for the "teaching" cbremer :) Scarey enough I do understand what boring an engine is, the rest is just way above me now.

Sweet man! Glad you got it together and all is well. IIRC the compression ratio of the Accurate Power kit is like 9.4:1 or so? That alone will require at least midgrade to ensure no pinging under any circumstances. If it is ok under most circumstances but worse when you short shift it a bit and lug it then octane should solve the problem. Otherwise it could be lean? But I think the 24 lb/hr injectors should be plenty of fuel...