258 Upgrade

[deadred]

Hello all,

I have a few questions I would like to run by everyone.
Background info 90 YJ with 170K on motor Liftes on pistion 2 & 5 are blown over the weekend I removed/pulled the engine/tran/transfercase

1. I have a stock 258 with 170k on engine should I bore it out to .60 over will this make the walls of the pistions to thin

2. what cam should I put in it

3. I have bought a 4.0l head and going to be installing it after the reworking of the head (3 angle valve job /ported and polished)

4. any ideas on the the compression I would have if the above was done?

5. I'm looking at the pacesetter dual outlet Exhast system whit there cat-bax system (any coments on use)

6. Am I missing any thing

Thanks in adavance
Deadred

[laneiac]

1. Do a .30 bore
2. Get either the Mopar performance cam or a Crane or similar
3. 4.0l head is a very good idea. I would do that as soon as possible.
4. I do believe your compression will be around 9.5:1, but dont quote me on that
5. I have heard good things about pacesetter, and you cant beat the price.
6. Nitrous.

[deadred]

Thanks for the info you think .60 is too much

[pushead]

.60 is not to much. Its a thick motor. My friend did his .60 over because it had some deep scratches. My short block went to the machine shop today. I will now tommorow what I am going to bore it to. I asked if it would be worth it to go .60 over. He said I would not gain a whole lot from it and did not feel I should spend the money unless I felt compelled. After all it is a I6 not a racing motor. For a good cam check for one of my recent postings. I got a good recomendation from a forum member on one. I havent decided on it yet though. I want to contact reed cams and see what they got to offer. Just waiting until tommorow to see what my motor will be bored too.

Also going w/a 4.0 head already have the pacesetter cat back sytem and just ordered a Luk Clutch kit for 170 including shipping, as well a pacesetter header. Pacesetter was the best price for a header. I am going to have a friend finish welding up the tubes at the top where they conect to the head. My friend has one and thought about it didnt do it now he has a crack. Just like in the Banks header adds. It should be welded up.

[currupt4130]

convert it to propane!

[deadred]

Thanks for the info

David

BTW I dont think I'm going with Propane With gas prices it might help though

[pushead]

I just got off the phone with my machine shop. My first cylinder on the block( I think the no 1 piston) was wider than the rest. He said that is very common for the 258. They are going to bore it to .40 over. The total for the shortblock rebuild will be $800. That will include all my gaskets, line boring, new timing chain and assembly. I ended up ordering the Comp X4254H cam and a melling oil pump. My total cost after completion will be $2000.00

parts:Comp X4254H, melling oil pump, Luk Clutch, Clutch master cylinder, Ford Taurus fan upgrade, 4.0 head conversion from Clearwater Heads, Por 15 thunder bird red engine kit, Por 15 Manifold grey kit, Pace Setter header, New head bolts

Bonus items I just picked up before I started this. New edlebrock shock's just came in I ordered 4 months ago. Used Bestop 6" extended flares but in great shape for $125.00

[yjdave]

For 2k i can install an 03 or 04 4.0l and still have more hp..........

[pushead]

Originally Posted by yjdave

For 2k i can install an 03 or 04 4.0l and still have more hp..........

go for it. I was not after horsepower. I wanted low end torque. If you read the parts list it was not all motor. I will still have more torque than your 4.0 will ever have unless you pay more cash.

[Junkpile]

Hell, even a short stroke V6 looks good if you only pay attention to the peak numbers.....and I would argue that a 4.0 wouldn't even have peak HP numbers as high as his engine. His 258 is going to be strong. If the rest of his Jeep is set up accordingly.......he'll be smoking 4.0s like they had "Marlboro" printed across them.

[hoobness]

I have the pacesetter header and the catback. -258- Theyre great. I have the smaller weber feeding them, and all the emissions ports plugged and or removed. It screams! I can cruise at 80 on the highway, and still have more than half the pedal to punch if I need to get it to 90 or 100 to pass. Had the needle pinned sunday and it got a little scary, but i had to see if it would do it!

I installed the exaust 2 weeks ago, and its a HUGE difference, any gear is quick and torquey. Not being able to ride in the fast lane was always my biggest beef about my jeep, now I can perform on and off the road!

hope this helps your decision.

[Junkpile]

You haven't really seen the difference a bunch of smog equipment makes until you've stripped a 258 down and experienced the difference. A 258 with a little more compression, a little more cam, and a good intake and exhaust is a totally different monster than came from the factory.

[hoobness]

Thats what clifford performance says. If you read the hp and torque gains they claim is possible with some mods, I see no reason to get a V8.
I love my 258.

[deadred]

An update:

I just conformed that the short block I ordered is bored-out .60 over
I have attached a spreadsheet of the other mods in doing in building the new block

Part description Part Number
4.0 Head + Shiping
Head Job/Valve Job
Short Block 204100
Oil Pan 53010340
FlowKooler High Flow Water Pump 1743
MSD Por-Billet Breakerless Distributor 8516
MSD 6 Off-road Ignition Control 6470
One Piece Oil Pan Gasket 53007568
4.0L Aluminum Valve Cover 563020323R
BombProof Engine Mounts 25842
2' Body Lift Kit 4WD821
Pacesetter Dual Oultlet Exhaust Header 701128
Pacesetter TFX Kat-Back Exhaust System 862872
Carburetor, Performer, 600 CFM, 4-Barrel, EDL-1406
Carne PowerMax Camshaft CRN-753941
Crane Anti-Pump Up Hydraulic Lifters CRN-99278-12
Accel Super Coils ACC-140001
Offehauser 360 Degree Dual Port Intake Manifold QFY-5999DP
Offehauser Universal Cable Linakage Accessory Kit OFY-6230


I hope to have it all installed by the end of next month

Just thought I would fill everyone in on the progress.

Does anyone know the factory block color



David

[hoobness]

wow, im jealous! You can drag race it too!

[Junkpile]

deadred--- niiiiiiice

Who came up with the combo? What's your estimate on how much power it's gonna make? Not knowing the compression (I'll assume 9.2:1)......I'll still make a guess, just for sh*ts and giggles: 240hp+ and 280lbs/ft. The beauty isn't in the peak numbers though, it's going to be a beast ALL the way through the operating range.

That 600cfm is kind of fat for that engine, but you should still be able to get it to run right with some playing around.

[deadred]

I’m working on the specs right now I'm using Dyno2003 to come up with the numbers. Once I have some I will post what I found out. To answer the question “who” came with the set up that would be me just from a lot of research online and through the different Mags I get. A little back ground I was about to buy a new Harley and then the jeep had a two lifters collapse. Once I got the head off I thought what the hell this motor has 170K on it time for a rebuild. I have been toying with the idea of a V8 swap out; I looked at the benefits and possible problems involved. Then I just decided to dive in once I got there I guess I went all out. Do it right or don’t bother. Needless to say I am spending most of my Harley funds on the jeep, but that will come in a few years.

[pushead]

Deadread, need to warn you about the pacesetter header. I just got mine yesterday for my 4.0 swap. It is set up to run torwards the front of the jeep and under the oil pan. I am not sure what I am going to do to correct this yet. But thought I would give you a heads up.

[hoobness]

whats wrong with that? Mine works great!

[pushead]

How did you pipe it? I have been trying to find some one who ran it this way. Did you just go under the frame on the pass side?