New 4.2L mini-stroker recipes

[Cheromaniac]

I believe that is what Josh is running and it’ll up his static compression ratio calculations more in line what he’s looking for

Yup. I make it 9.50:1.

[jpradcliffe]

Not Silvolite. 677AP +.030. 15cc dish. Hadn't know those had a larger dish when I ordered them. Oh well. I'm thinking that the low 9 compression is ok considering could always play with a small amount of boost, provided I don't float a valve lol.

[jpradcliffe]

[Cheromaniac]

Not Silvolite. 677AP +.030. 15cc dish. Hadn't know those had a larger dish when I ordered them. Oh well. I'm thinking that the low 9 compression is ok considering could always play with a small amount of boost, provided I don't float a valve lol.

It'll be fine.

[jpradcliffe]

Ok so. Big thanks to Russ for the roller rockers!

Now: Lifters, gasket, head, pushrods & rockers installed.

Oil pump primed.

I go to hand crank the motor to check rockers and pushrod lengths andddddd....... Da dah. Motor will not make a full turn.

I Drain the oil. Pull the pan. And....Guess what?

Ye ol' machine shop had "neglected" to shim/washer the main girdle.

Rods would have hit the girdle and the Motor would have been destroyed on first crank.

I am sure there is wisdom on this subject and would greatly appreciate any advice.

This video https://youtu.be/wH3MkRHSyw0 says to add washers on rod stud and under main....I am not sure that is wise. Please advise.

[jpradcliffe]

Ok so. Big thanks to Russ for the roller rockers!

Now: Lifters, gasket, head, pushrods & rockers installed.

Oil pump primed.

I go to hand crank the motor to check rockers and pushrod lengths andddddd....... Da dah. Motor will not make a full turn.

I Drain the oil. Pull the pan. And....Guess what?

Ye ol' machine shop had "neglected" to shim/washer the main girdle.

Rods would have hit the girdle and the Motor would have been destroyed on first crank.

I am sure there is wisdom on this subject and I would greatly appreciate any advice.

This video https://youtu.be/wH3MkRHSyw0 says to add washers on rod stud and under main....I am not sure that is wise. Please advise.

[Cheromaniac]

Here's your answer:

The rod caps wouldn't clear the main bearing stud girdle, so two 5/16" hardened steel washers had to be inserted on each stud to raise the girdle and provide the necessary clearance.

[jpradcliffe]

Ah. Why thank you.

So I just decided to clearance the girdle at the contact point. Fits and rotates perfectly and the pan fits without the need for further modification.

So that's good.

Anywho. I have another query.

So being that my
Dynamic compression is 8.54 and my
Static compression is 9.15,

Were I to run a small turbo and intercooler setup at say 6 to 8 #'s of boost, what injector would I need? (I've read that folks are running 36#) but at what psi?

I'm currently at 39# ....provided I size the injectors properly, can I get away with running this setup with just a boost referencing fuel pressure regulator and check valve on map until I can understand/afford a mega squirt?

Please advise and thanks in advance.

[4.2stroker]

I have a 4.2 stroker engine
2000 xj block
Bored .60 over
New silvolite UEM-2229 pistons installed on the 4.0 rods
AMC 232 crank ground and polished .10/.10 and the snout shortened to use the serpentine crank pulley
0630 head resurfaced
New valves springs retainers and keepers
Mild cam from comp cams
New oil pump and pick up tube

What fuel injectors would you recommend for my 2000 xj?

What other parts would you recommend that I change?

The xj that the motor is going in is completely stock

[Cheromaniac]

The Bosch 0280155703 injectors should do the job. To help your 4.2 stroker breathe, I suggest you add a 62mm TB, header, and 2.5" exhaust.

[4.2stroker]

The Bosch 0280155703 injectors should do the job. To help your 4.2 stroker breathe, I suggest you add a 62mm TB, header, and 2.5" exhaust.

Thank you I appreciate your help

[Jed]

So I think I had a mini stroker I got out of trade. I had to replace valve cover and oil pan. Someone dropped it off a fork lift. It also sat on it side for 3 + months after being jumped through a barn. It ran great for A few years. Then I thinking it broke from camshaft thrust and would eat the gears off my distributor.

I say it’s a mini because of the Size of the lobes on the cam. I was trying to figure out what can I should buy to replace the one I had. I saw the lobe size was smaller than a stock 4.0. So I ask about it on the forum and someone pointed out that my cam was from a 4.2 due to the size.

So I replace it with a cam from cleggS stage one cam and did throttle body lifters and rods. It runs hot now but sounds good but did I make the right choice in cams? Is the cam the reason it runs hot now or what’s the deal can you help me thanks

[Russ Pottenger]

Jed,
To help advise you in selecting a Camshaft is your block a 1999 and later block utilizing thrust plate style cam and are you planning on retaining your stock valve springs?

[D'sJeepWrld]

Hey guys so my jeep is going under the knife again and i didnt plan on a "rebuild" I really just need cam bearings but i gotta pull the rest of the block out for that...
With that being said im deciding on getting a 3214722 crank 72' after year so it should work in my auto 05' Lj ?
Will the Silvolites 2229c Pistons be enough for what i like to do ? That being Rock crawling and being a daily being driven 90 ish miles a day,constant abuse,hanging on to limiter for minutes on end doing donuts/drifts BUT i also do want to run a max of 150 Shot of nitrous here and there but.... im being extra with the Nitrous...I have some of the stuff to make it work just need a place to mount it in my jeep so its nots like i need it but rather want it XD

Or Like Mr.Cheromaniac said i could run some Sealed Ppwer H802CP's since im more confident with the hyper. pistons being able to handle The nitrous a bit better and the Turbo setup i plan on doing later on ! But in that case id like to run some forged pistons rather than the hyper. pistons since they share the same comp. height so id only need to run a "thicker headgasket" maybe a .060" Cometic Gasket ?

Parts i have
Edelbrock aluminum head, Some american racing headers i got for 400 bucks new!
68-235-4 254/262 Duration at 0.477 int./0.493 exh. 111 LSA I may advance it 4 degrees,bump my DCR. a bit
JP Performance Dual roller setup,Bolt/spring setup from newcomer racing

Plans
Send block to get bores machined .030" Over, Deck the block as little as possible due to the larger stroke? what would be my quench with the 3.5 Stroke crank ?
3214722 Crank, it should work in my 05' Jeep Lj ?
DSS 2618 3.905 Bore Forged pistons +15cc And some bushed forged rods OR Just some SilvOlite 3241HC's or its equivalent i.e Sealed power H802CP's and some stock rods Weaker but alot cheaper, I need/want my jeep back in a month or 2 since it is my daily thats driven 92 miles a day

If anyone can chip in with what i need to do let me know it will be appreciated cause i really want to do the 232 crank since im already here and im in for a rebuild even if it means using affirm to buy stuff...None the less i want to get the ball rolling ASAP ! Im exited to see once shes running !

Also here's a screenshot of everything i.e DCR and stuff would it pan well with 87 octane ? Im assuming the aluminum would help to keep my ability to run but if 89 is required with a DCR of 8.23 or 8.30 let me know what my limits are ! ⤵

Screenshot (473).png

Keep in mind i was only gonna do that eddie head,ARH Headers and bigger cam setup but my cam bearings are a little beat....and for shits and giggles i have some silvolites 3241HC's and my plan was to do a quick rebuild but this is no longer my case cause of the cam bearings...

[D'sJeepWrld]

My screenshot didn't show up...

Screenshot (473).png

And for some reason my Ip is blocked on my PC but on my phone there's no problem...