SIJA

All right, I finally had time to sit down to get some information together about my little stroker Project. I'll Try to break this all down into easy to read sections I'll update the sections as needed.

Original Goal:

Well to build a Stoker of course! Mostly I wanted to see how hard (and expensive) it was going to be to do this. I set out with the intention of reusing as many parts as I could, make it as reliable as possible, and to see how much 'oomph' I could get out of all the 'low output' Renix (1987-90) junk.

Driving Impressions:

I am 18mi away form my 500mi Break in period. So while I haven't done any real hard pulls yet (Haven't let it shift above 3500rpm), there is a very noticeable difference in power with this thing as opposed to my '92 XJ HO. I hope to get a few hard runs in soon to give some Butt dyno reports ^_^ As for now, it pulls hard even with me just babying it around for the most part. I don't hesitate to pass people anymore to be sure ^_^ It does have a slight 'lope' at idle, but I am uncertain if that’s more being caused by the 20 year old Renix system, or if the cam is just enough to make it to that. Zero Overheating Problems as of now

Renix Woes:

I've nearly finished working out all my little quirks (mostly due to the old sensors) and I've finally got it to the point where I'm 98% happy with its current Running Condition. The other 2% of its quirks don't really bother me enough to fix them at this time.-- Edit - other than an apparent over cooling problem, I'm competely happy with how its running.

My working Stroker Combo (4.7L):

4.0 Block (1987-90) Casting #8933002665
4.0 Head (1987-90) Casting #2686
4.2 Crank (1987-90) Casting #3727
4.2 Rods (1971-81) Casting #707
Fuel Injectors (1987-90) PN# 53003956 (18.6 lb/hr @ 39psi) Yup they're dirty and well used at 195k mi on them Edit: I'm now running Ford Motorsport 24.0lb/hr @ 39psi (Part no. FMS-M9593-A302) The motor is much happier whith these injectors, though it runs a tad rich. I believe this is due to a bad CTS that I need to swap out (I'll update when I know for sure 4/2/09)
Erson Cam PN# E72011
Sealed Power Pistons PN# H825CP (.060" Machined out to reduce the Compression ratio to the stock 8.8:1)
Cleveite Bearings and Felpro Gaskets
CFI 3row Radiator, Mechanical Fan (no electric) Runs at 180* at idle it sits at 210* (94* day)
Stock plugs but with .045" gap (stock gap is .035")

Estimated Numbers:

approx 230hp and 310ft/lb (these are best educated guesses, IDK if it'll ever hit a dyno)

Things I would have done Different:

Fixed all the dang problems it had! I've spent many hours tracking down bad grounds, bad sensors, and just plain bad junk! The problems the old motor had electronically were magnified when a good running motor was put in! So the moral of the story, if you have a bad O2/MAP/MAT/TPS/IAC/CPS/XYZ sensor when you pulled the old motor, they're still going to be bad when the new one goes in

The moral of the story is:

I don't know, but I'm glad I did it, I'd do it over again. And I can't wait to do it to the '92 now ^_^ Edit --- I sold the '92

SIFCO Stroker Labor Rates:

!!All Numbers are Approximate, Call Bob for more specific Numbers!!!

These Prices are not set in stone, but the numbers below should be considered a 'worse case high price' Talk to Bob for a more accurate number...

Line Bore (if needed) --------------------------------- $150
Tank/Bore/Hone/Install Freeze Plugs/Cam Bearings - $110
Grind Crank (If needed) -------------------------------- $125
Balance Rotation Assembly ---------------------------- $160
3 Angle Valve Job --------------------------------------- $125
Press Pistons --------------------------------------- $48
Recondition Rods --------------------------------------- $48
Machine Pistons to Desired Compression Ratio ------- $60
Motor Assembly ----------------------------------------- $150
CC (if Desired) ------------------------------------------ $35
Total For worse Case Labor----- = $1011
10% Discount if all services are done New total =$909.90

Now we can play with the numbers some to get them down. For example, if you have crank that doesn’t need to be ground, that'll save some money, don't need a valve job? There’s some money saved there too. So let's do it on the cheap.

Cheap Labor Stoker:

Line Bore Inspection --------------------------------- $25
Tank/Bore/Hone/Install Freeze Plugs/Cam Bearings - $110
New Crank Grind not needed--------------------------- $0
Balance Rotation Assembly ---------------------------- $160
Skipped Valve job ----------------------------------------- $0
Press Pistons --------------------------------------- $48
Recondition Rods --------------------------------------- $48
Machine Pistons to Desired Compression Ratio ------- $60
Assemble motor yourself ------------------------------- $0
Skip CC'ing ------------------------------------------ $0
New Cheap total -----------------------------= $451

Parts:

Complete Kit from SIFCO Includes but not limited to:
Cleveite Bearings
Melling Oil Pump
Felpro Gaskets
Sealed Power Pistons
Erson Cam
ARP Rod Bolts
---------Sub = $503.63
Rods = $60
Crank = $250 (Includes a $40 core for 4.2 Crank)
Total = $813.63

So for the complete SIFCO Stoker Package(with you providing a usable core 4.0 block and head) the Grand total will be in the neighbor hood of $1824.63 - $1264.63.

Again, THESE NUMBERS ARE NOT FIRM! For a complete quote Call Bob

Need to Call Bob?

You can Reach either Bob or I at
SIFCO Machine
#101 Jerome Lane
Cahokia IL 62206
618-337-9939

We are a full service Machine shop Specializing in Aerospace and Automotive Machining!

All right Benno Tired now ^_^ I have GOBS of information on this stroker stuff, everything from casting numbers to injector sizing. If you'd like to see some more information, just post up, and I'll amend this top post.

Thanks for Reading

-Benno!

EDIT: MPG's with 3:55's and 225's (with the 4.0 I would average 19.5-19.9)
Tank 1 - 17 mpg ( First tank while breaking in the motor, Heavier foot than normal for me )
Tank 2 - 17.6 mpg (motor broken in, some hard pulls in there)
Tank 3- 18.78 mpg (90% highway running 65-75 from O'Falon IL to St. James Mo).

800 Mile Update

Well the motor is throughly broken in at this point (even had its first oil change) and all seems to be well. I am noticing a few things though:

1 - I'm noticing a distinct difference in power between running WOT and say 85% ish throttle on the hard runs. I know when running WOT, the computer goes into a 'closed loop' so it ignores what the sensors are telling it and runs on its own chart. The fix for this is either (a) don't run WOT (b) Look into building or buying an Adjustable MAP sensor. Personally, I think it still pulls hard enough at WOT to not make me worry about trying to fix it. (Fixed - See Below)

2 - Random Miss at 3200 RPM - While I know My Tach is off by a good 500 RPM, I can safely say I've got a miss while running 75mph ^_^ I'm going to go out on a limb and say its probably due to old, semi clogged fuel injectors. So I guess I'm going to go look for some less used ones or getting my spare set cleaned (which ever winds up being cheaper) --(Fixed - See Below)

Edit 12/29/07 - Fuel Injectors

My 24#/hr injectors are now installed --Ford Motorsport 24.0lb/hr @ 39psi (Part no. FMS-M9593-A302) .

Can we say "Holy Crap"?

I never would have guessed that the injectors would have made as much of a difference as they did. I still have some idle lope (which I like), but it idles much smoother, pulls hella harder, and my knock sensor isn't pulling timing anymore. I've got my little Hot Rod back again ^_^

So with the new(ish) injectors, the WOT problem is gone, as well as my random miss.

Edit 9/14/08 - The Near One Year Mile Maker 10k mark

A few things have happend over the course of this year...
-I've changed jobs, so I'm no longer working with SIFCO, however he still does do the stroker work and I recomend checking him out if you're considering doing a build for one.
-I've gone back to school as well, so I haven't been able to play with the XJ as much as I would like to (only made three trips this year since the New Years day run).

For the motor: The thing just keeps on impressing me, its still reliable as a stock 4.0, runs cool, and seems to be getting great milage with the 32's and 3:55's (looks like 18/19 mpg's If I keep it under 65 ish). Running 70-75 on the Highway it's getting 16-17 mpgs.

So the end story, I'm still happy and would recomend it to someone who's thinking about doing one ^_^

But the lightening bolts on the sides of them must bring it up to 240 hp

I need to go over rev my Junk.. how do you disable a rev limiter?????

Some of the power chips do that. Or allow you to raise it.

just pull a plug wire and tell her its blown somewhere...lol


Kage thanks for the info...my bro and i were talking about doing this to the MJ in the future. I've heard that the Renix 4.0L are stronger blocks due to a higher nickel content(i think) only bad thing i gonna have to add a ton of weight to the rear because it'll brake torque the 35's rear easy and in rain it very hard to keep traction...lol

You running a 5spd or AW4? I know in my XJ (AW4) with bald tires its mostly manageable The 87-90 4.0 block is more desireable as it does have a higher nickel content, and it is suppose to be a heavier block as well ( I don't have a HO bock ATM, so I can't verifiy the second claim).

If so desired, I can throw up some specs for a few other stroker combinations.





Well, I wouldn't try to throw a rod out of the side, as we need that block to make your stroker ^_^ So just tell her that all you're overheating problems have caused your pistons to gall up, and that the only solution is to rebuild the motor...... And you'll have to sell that silly YJ to do it

Edited top post a hair for MPG

-Benno!

Pfffft!

I'm runnin' 0.065"

Edit top post for MPG and 800mi Update

$2000 for 50hp over stock?? Dont know if i'd go that route.

Not sure where you're coming up with the $2k price tag, as I put up there the High end would be $1824.63

I was afraid of putting any price numbers up there because of a post like this, but I wanted to give everyone a worse case number to go by. If you look at the price break down, you can save yourself some decent money if you were to find a good 4.2 crank/Rods. This would also save you money on some of the machine services (since if you have a good crank, then we won't have to polish/grind it).

But if you'd like a little comparison. This is one of the most popular Stroker provider out there now. And this is their pricing on machine work.

The end game is that it really isn't that much more expensive to do a stroker over a standard rebuild, but if you have a really messed up core block/Crank, then you should be ready for the price to increase.

Bottom Line is that if you're seriously considering doing this, then give us a call, and we'll nail down a firm price.

And finally, you advertise HP and Drive Torque. That's especially true in our sport, as most of the time, we're not usually running full throttle in the upper rev's (well some of us anyway).

I hope I helped clarify this, feel free to post any more questions if you have them.

-Benno!

50 HP is better than a 20% increase. You get a drop in place new engine on top of it? No brainer.

Power cost money.

I've dropped close to a grand on my DD for a 30 hp increase... and to get any more means supercharger which is big bucks.

For me this is what hits the nail on the head. Will I go out and upgrade a good running 4.0 to a stroker? No would be the answer to that question for me. I would consider this for an engine that needs to be rebuilt. If you are overhauling anyway, why not consider the stroker option for a few more dollars.

This stroker is an ANIMAL. If you even remotely thought about it... performance differences is incrediable... Renixs and low flow head aside... it's a mid 15 second XJ right now... Bottom end torque is deep... nice cam / engine lope... close your eyes and invision built small block sound...

My Vic runs a consistent 15.4 all day long.. By the time we hit 65mph I was only a 1/2 car ahead....

Now I gotta think of excuses... "Ummm... BossLady.... I think my overheating problem is more serious now..."

thats the plan for when the MJ needs a rebuild in a few years..

You got it Eric! Essentially you're talking about $310 for crank and rods (unless you find your own) and $60 for Machine work to the pistons.

So for $370 worth of parts and labor over a standard rebuild (or if you have a good crank/rods, $60), why not? You'll wind up with more power, equal to or better mpg, and a fresh motor.

Sure, you can swap in a SBC or Ford for more power, but then you have to take care of all the headaches that go along with that.

Or I guess you could throw a bottle on it, but if your rig is already on its last legs, then that's not really a long term solution (but it is cheaper )

So, would I tear down a good running 4.0? In a heartbeat But considering that most of us are starting to run high mileage stuff, the rebuild becomes inevitable.

If someone would like to go for a ride, feel free to call me (Phone# is in the members section).

Thanks for the reply's, and of course, any questions, feel free to post up or pm me.

-Benno!

well the wifes xj hit 100k