4.0 Blew, Need help on 4.6 Stroker route

[KnightSRT]

New to the boards and I'll be brief with my scenario:

Sold my 97 TJ and Got an 01 XJ ( needed the room /better daily ). Replaced the head gasket twice ( first time machine shop screwed up valve job THEY recommended). Idled great for 40 mins, then took her out for a drive and POP. Rings let go so it time to do the stroker (if I am in there I want to do something more).

So I have a few questions on what I need on the two routes I have come up with :

1) Titan Engines have a lower end kit that uses 4.0 rods/their crank/ and KB pistons for 940 shipped. Comes with Rings/Bearings/ everything needed for the lower end. This seems like the most safe route as less error for me to order wrong stuff. Anyone have any good/bad to say about this kit?

2) Second route would be the Poor man Stroker kit:
-4.2 (258 crank) - I can get that through my parts place at work for 130 comes with all the bearings
-4.2 rods/4.0 rods- Not sure which to use?
-As far as pistons go I am at a total loss. I have been browsing the boards before joining and saw that some people use the 4.0 pistons with 4.2 rods?


Last of the questions:
-Will I need the 24lb injectors?
-Keeping the stock head/cam will a MAP adjuster be needed?
-I keep seeing something about having to deck the block for a certain quench height. Is that needed on every build, or is that based on if you get a domed/flat style piston.

This is my Daily so I am not trying to go hog wild, just figured I always wanted to do a stroker in one of my jeeps, and now seems like the opportune time. Any input or advice would be appreciated! The engine builder is going to call me Monday when he has it torn apart to let me know about boring and what I need. Thank you for any help/advice you can give!

[honkysXJ]

Sounds a lot like what happened to me ,if you gotta rebuild might as well upgrade right!
I pieced my parts together for 2 reasons first one being I wanted to know exactly what I was getting, and lastly I didn't have $1000 to drop on parts all at once.
Not sure if you've seen dinos site or not but he has several recipes listed on there from mild to wild ,the "modified poormans stroker" seems to be a pretty popular one and it's the one I'm going with the only things not stock are the Keith black 944 pistons and the 258 crank .. your limited on camshafts if you want to keep stock springs, but a lot of people are running stock cams in their stroker with no complaints!
As far as quench from everything I've heard between 40-50 is a good goal to shoot for and unless you get custom pistons to reach that quench you'll have to deck the block.
By the way welcome to the site ,you came to the right place there's a lot of guys with a lot of knowledge on here

[KnightSRT]

I have read over Dino's articles, and that's how I came with the poor man stroker, but that is where the cost came into effect. 4.2 Rods are 55 a piece, and then the KB pistons are 500 for the set, which put me back to the 1k without bearings. Reason for me looking at the titan kit. I was kinda hoping he would chime in here .

I do plan on sticking stock cam for sure just on reliability/less issues to deal with. Im not going to lie I am excited to see the power difference with this, even though on my 35s and stock gear lol. (3.73's)

[honkysXJ]

I got my kb pistons for 345 shipped less than 2 months ago from titan, they don't have the best reputation for crate moters but I was very happy with there customer service and have no complaints then again all I bought was pistons ,I priced them everywhere and titan was by far the cheapest! Unless you find a deal on a used 4.2 engine on craiglist or something you might as well stick with the 4.0 rods with the kb pistons! I'd keep checking locally for 4.2 engines tho cause a lot of times guy's are doing v8 or 4.0 swaps and don't even know what they have.
I got over $1000 wrapped up in parts so if you got the money to drop on a kit and your in a rush go for it , you might be able to save a few bucks by piecing it together yourself but shipping and handling adds up as well
I'm sure dino will chime in I think he's on here everyday just like me
Another thought is maybe you can contact titan and have them help you build your own kit,you said your using the stock cam anyways maybe you can get a deal on crank/pistons& bearings if you buy em all at once
on't hurt to ask,they had my pistons listed for 450 and when I called to ask about them they happened to be on special!
Good luck with your decision!
Id take my XJ over a wrangler anyday

[KnightSRT]

Yea I called and talked to a guy named Keith. VERY knowledgeable guy after talking with him for about 15 minutes. I am on a short time span and I just like the idea of having all new parts that match with the kit. Maybe they will know if I need to deck the block to reach a certain quench number ( which I think I need?)

What compression ratio did you go with on your KB pistons? I think I remember reading dino said staying somewhere around 9.2:1 if you wanted to run 87? I think I will atleast always run 89 in it, but not sure on the 91 as my SRT-8 eats my wallet on that already lol

Kit was 900 shipped for : Crank/rods/pistons/rings/bearings.

[Cheromaniac]

Got an 01 XJ

1) Titan Engines have a lower end kit that uses 4.0 rods/their crank/ and KB pistons for 940 shipped. Comes with Rings/Bearings/ everything needed for the lower end. This seems like the most safe route as less error for me to order wrong stuff. Anyone have any good/bad to say about this kit?

2) Second route would be the Poor man Stroker kit:
-4.2 (258 crank) - I can get that through my parts place at work for 130 comes with all the bearings
-4.2 rods/4.0 rods- Not sure which to use?
-As far as pistons go I am at a total loss. I have been browsing the boards before joining and saw that some people use the 4.0 pistons with 4.2 rods?

You could use the Titan Engines lower end kit to build a modified poor man's stroker with the following specs:

4.6L modified "poor man's" stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Keith Black UEM-IC944-020 forged pistons
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.070" quench height
Accel 24lb/hr injectors for '96-'04 engines
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

Their kit seems like a very good deal.
You could cherry pick the 259 crank, IC944 pistons/rings, rod/main bearings separately and reuse your existing 4.0L rods but by the time you factor in the cost of regrinding/polishing the crank journals and resizing the rod big ends, you'll end up spending more than you would to buy Titan's kit.

[honkysXJ]

I went .30 over on my pistons ,my block needed .20 minimum to be cleaned up and the machinist recommended .30 and I decided to deck the block to tighten the quench to leave the pistons .5 in the whole for a 48 quench with a 43 head gasket which bumped the compression up to 9.6ish but I've been running premium lately anyways and my Xj is a DD so I don't mind the extra $5 per fill up

[KnightSRT]

Got an 01 XJ

1) Titan Engines have a lower end kit that uses 4.0 rods/their crank/ and KB pistons for 940 shipped. Comes with Rings/Bearings/ everything needed for the lower end. This seems like the most safe route as less error for me to order wrong stuff. Anyone have any good/bad to say about this kit?

2) Second route would be the Poor man Stroker kit:
-4.2 (258 crank) - I can get that through my parts place at work for 130 comes with all the bearings
-4.2 rods/4.0 rods- Not sure which to use?
-As far as pistons go I am at a total loss. I have been browsing the boards before joining and saw that some people use the 4.0 pistons with 4.2 rods?

You could use the Titan Engines lower end kit to build a modified poor man's stroker with the following specs:

4.6L modified "poor man's" stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Keith Black UEM-IC944-020 forged pistons
9.25:1 CR
Stock 4.0 camshaft
Ported HO 1.91"/1.50" cylinder head
Mopar/Victor 0.043" head gasket
0.070" quench height
Accel 24lb/hr injectors for '96-'04 engines
245hp @ 4800rpm, 315lbft @ 3000rpm ('96-'04 camshaft)

Their kit seems like a very good deal.
You could cherry pick the 259 crank, IC944 pistons/rings, rod/main bearings separately and reuse your existing 4.0L rods but by the time you factor in the cost of regrinding/polishing the crank journals and resizing the rod big ends, you'll end up spending more than you would to buy Titan's kit.

Thank you. Would the head not being ported be a huge deal? I have enough coin to get the stroker done, not the porting (never happens when I have cash lol) .

Also Stock Map with the 24 lbs should be fine?

[KnightSRT]

I went .30 over on my pistons ,my block needed .20 minimum to be cleaned up and the machinist recommended .30 and I decided to deck the block to tighten the quench to leave the pistons .5 in the whole for a 48 quench with a 43 head gasket which bumped the compression up to 9.6ish but I've been running premium lately anyways and my Xj is a DD so I don't mind the extra $5 per fill up

Agreed on that. As far as figuring out quench. Should I assume to take off the block as much as the poor mans stroker? Not sure if the builder will know what I am talking about as all I have ever done was milled heads to lower comp on cars.

[Cheromaniac]

Thank you. Would the head not being ported be a huge deal? I have enough coin to get the stroker done, not the porting (never happens when I have cash lol) .

Also Stock Map with the 24 lbs should be fine?

Should I assume to take off the block as much as the poor mans stroker?

Not having the head ported isn't a huge deal but it'll cost you ~20hp. Stock MAP with Accel 24lb'ers will do fine.
The modified poor man's stroker doesn't require you to mill the block/head at all except the minimum needed to make the surfaces perfectly flat. The quench comes in at ~0.070. If you want to reduce the quench to 0.050", you'll need to take 0.020" off the block and that'll raise the CR to ~9.6. You could bring it down again by polishing the combustion chambers smooth to regain some volume and that'll help prevent detonation.

[KnightSRT]

Any place on where to get the best deal on the accels? I found a company on ebay that has 24lbs for the EV6 for 169.99 shipped. They were not accels though

[Cheromaniac]

I found a company on ebay that has 24lbs for the EV6 for 169.99 shipped. They were not accels though

Those should be OK but check at what fuel pressure those 24lb injectors were rated at. Your Jeep's fuel pressure will be 49psi.