Hello and help!!!!

[Sighman]

First let me say hello everyone! Second I'm here because like everyone else I'm doing a stroker build. Third I'm clueless with all the specs so here I am! I have the following to work with:

Block – (1999) - 53010449 NVH
Crank – (1981-1986) - 3235477
Rods – (1982-1990) - 352 casting
Head – (1999-2004) - 0331 casting


My Jeep is an 01 auto.

I make the following statements based on what I've read so far.

1.) I will need to bore the block 30 over
2.) I will need 30 over pistons
3.) The block will need shaved by 10?
4.) Crank will need ground
5.) Polish and port head
6.) New injectors (24#)?

I would like to run stock cam, throttle body, and valve train. Am I even close to understanding this correctly?

[Cheromaniac]

Go for the minimum cylinder overbore that'll make them round and true, so you might only need 0.020". Get the appropriate size pistons and rings.
The crank journals may need to be reground 0.010" undersize depending on their condition. You will of course need 0.010" undersize bearings.
It wouldn't be a bad idea to shave 0.010" from the block deck to increase compression ratio (by 0.2) and reduce deck clearance.
A head port job will yield a few HP so it's definitely worth doing.
24lb injectors would be fine but you'll need the newer pencil style units. Try http://www.fiveomotorsports.com

[Sighman]

Thanks for the reply, of coarse I now have even more questions!

1.) The cylinders are fine and only need honed, the reason I was going to bore them was to keep the compression low? (running street gas)
2.) I would be happy to run the stock injectors if it would work?

[gremlinsteve]

squish is the better route to being able to run lower octane fuel.
if you get the squish tight in the engine, it causes turbulance. less likely to detonate.
so, that being said, i would recomend having your machine shop get the piston to zero deck.
then you can run the .051 vr gasket and have a near perfect squish.

camshafts...stock camshaft is prolly going to throw you a loop....meaning the cranking compression ,might be a bit higher than what uyou would want. not saying that that is bad.....

i would like to see what stock cams are putting out as far as cranking compression in 4.5-4.7 liter motors..



steve

[Mgardiner1]

camshafts...stock camshaft is prolly going to throw you a loop....meaning the cranking compression ,might be a bit higher than what uyou would want. not saying that that is bad.....

i would like to see what stock cams are putting out as far as cranking compression in 4.5-4.7 liter motors..

steve

Interesting that you mention that. After only having my stroker running for 2 days (really only running good for one) i've noticed that it definitely feels/sounds like it builds more compression during cranking. Using a Mopar 30AB cam

[seanyb505]

Thanks for the reply, of coarse I now have even more questions!

1.) The cylinders are fine and only need honed, the reason I was going to bore them was to keep the compression low? (running street gas)
2.) I would be happy to run the stock injectors if it would work?

1.) Increasing bore increases compression
2.) Better to run rich than lean. If you look long enough you can find some 24# injectors on ebay for $50-100.

[bratcop]

I, by no means, know as much as these other guys, but you have not mentioned pistons...

going back with stock or? This should be a consideration, because if you deck the block on the '01 like I am, then the compression will go up, and can easily crawl up on a 10:1 Cr with mostly stock replacement pistons (enginetech equivalent to 677cp, but hypereutectic), which would probably be undesirable if you were to run 87 oct. pump gas...pre-ignition ping. This of course requires lowering the compression, likely from dishing the pistons, which brings us full circle, can the pistons you have/ordered be dished enough to lower the CR adequately? It becomes a sort of battle between quench and compression, one goes down and the other goes up...

I have the 24# injectors now and was worried about the speed/density system used to control fuel mixture in open loop with my new variables (ported head and intake, bigger injectors, larger displacement). Because of this concern, i bought a PSC1-003 to adjust the MAP signal across the entire rpm range. I assume it will be mostly ok in closed loop, but idle and WOT are a concern...

Of course, if you want to know your true A/F mix, and subsequently be able to truly tweak the PSC, a wideband O2 is necessary, and from what I have seen, the Zeitronix is a very functional unit which doesn't need a specific display (only a laptop, perfect for tuning only).

Just my two sense, as my current application is fully theoretical, as my block is at the Machine shop being decked and checking squish.

Just one more thought...if we are going to be playing with the engines and their subsequent ECU's, probably best to get an OBDII reader. I have found some online and local to me...would be nice to read internal codes, TPS values, O2 values, etc while tweaking...

Again, just my .02

check my build at...
http://www.jeepstrokers.com/forum/viewt ... f=15&t=438

Bratcop

[Sighman]

I was going to reused the old 4.0 pistons but once again like you say compression and quench are factors....still not sure which way to go. I have a slight rob knock in my current 4.0 but still run around 50 psi on the oil pressure. I was hoping to change it out for this stroker I'm building this winter but all the confusion I have (or lack of understanding) might make have to hold off!

[John]

Make haste slowly. Keep asking questions and we can help. You sound like you are thinking your build carefully, keep going...
John

[Sighman]

That's the plan, I want to do this once, not turn around a couple months later after it blows up!

In theory the more I read the more i understand about all this. I live in a rural setting in Texas so when I take the motor into the shop I want to be very clear about what I want done!

[Sighman]

Ok here's where I am so far. 4.0 is all torn down and block, crank, pistons, rods and head are off to the machine shop. Starting to clean up all brackets and parts, some are already cleaned and painted. We (my 16 year old son and I) decided to go with a candy apple red paint for the parts and I have to say it looks pretty nice. Long way to go but as stated we're taking our time!



Here's the Jeep it will be going into:

[bratcop]

Nice color...I love it when someone has the courage to paint boring parts (timing cover, valve cover) something that isn't boring...It looks great. I, however, will be sticking to black and silver, as I am obviously a coward... The Jeep that gets the transplant is a sweet looking ride...I love the flat front fenders, and Ican't wait to see the red under the hood when you are finished...it's going to look great...


Bratcop

[Sighman]

Thanks, I just had to do something with it! As the Jeep spends most of its time playing in the dirt and rocks it will probably only look good on the stand, as soon as its in the Jeep its probably going to get dirty fast!! I'm taking my time so this gives me something to do while I slowly build it up. It's amazing how long it takes to hand clean all the parts