For you 4.6 stroker folks!

[brokenujoint]

Ok so as I build my stroker(actually I've coped out and decided to buy from Golen) I am ever searching to pinch as many ponies and upgrades to the motor. One of the more hands on upgrades is my 4.7L Dodge Dakota 68mm throttle body conversion.

I have a 97 tj with the 4.0. I've read on the net that if you go with the newer 99+ intake manifold that it will afford you as much as 10 hp stock and as much as 25 hp w/a stroker.. NO BRAINER!.. so i got onto www.car-parts.com and sourced myself a intake manifold from a 03 rubi for 120.00 shipped. perfect... I striped it, ported the runners a little bit (key word: a little bit), and then painted it up with a high temp engine aluminum color paint. turned out very very nice.

Next on the list was my intake.. That was a 81.00 delivered to my door BRAND SPANKING NEW (quality) 68mm TB. SCORE!.. Now the hard part... Mating the TB to the intake..
I went down to my local Patton's metal supply yard and bought a 8"x8" 1/2" thick plate of aluminum for about 8.00. I didnt have to have them cut it down so that saved me a few frogskins.
Then I went home, made a paper template of the mounting surface of the TB, and cut it out. I then made a paper template of my intake manifold's mounting points. I then fused the two together and made one master template. I then copied that template to the aluminum and began my die grinder, air grinder, port kit (left over from an aborted ported head project). i also used a hacksaw to get it to its basic dimensions.. I then bought a holesaw and cut out the center section of the spacer. I then milled out the intake's tb entry hole to match. I then drilled, tapped, and countersunk all that needed to be done..
I then went to the local pick a part and pulled a tb linkage off of a 93 xj(they just bolt right off). cost, 2.00. I got home and hacksawed the nipple off of the linkage and welded it to my 68mm tb. As long as you have a manuel tranny its fine. auto, you'll have to weld the whole linkage to the 68mm linkage.. all of the IAC and electricals swap over.. easy breezy.

with the 99+ intake and the 68mm tb, i can expect to pinch a good 35hp out of the stroker. I'll be putting on some ford motorsport cobra injectors as well. extra fuel in, extra air in, extra exhaust out.. Thats another story(3" exhaust with a fabbed up banks header..
And heres a few pics thus far!. enjoy!



You gotta love the nice lines.. HARD WORK PAID OFF

Picture of the linkage before welding.

It doesnt much smoother than this!

[cbremer]

nice job! with that kind of airflow, long hills should be no problem. wouldn't 3" exhaust put your peak power at high revs though? i mean, the ZJ V8 only has 2 1/2" exhaust OE, of course.

Also, don't go too big on the injectors- I failed smog with 26 lb/hr injectors in my 4.6 (ran way too rich- i don't have the later intake & TB though). 24 lb/hr injectors got me passed with no problem.

[swbooking]

nice job! with that kind of airflow, long hills should be no problem. wouldn't 3" exhaust put your peak power at high revs though? i mean, the ZJ V8 only has 2 1/2" exhaust OE, of course.
Also, don't go too big on the injectors- I failed smog with 26 lb/hr injectors in my 4.6 (ran way too rich- i don't have the later intake & TB though). 24 lb/hr injectors got me passed with no problem.

Yeah really nice job. It looks super clean. 3" wouldnt make the peak power too high i dont think, but maybe a 2 1/2" would be better. Oh and anyone can pass smog (whether your car deos or not)

[brokenujoint]

a number of guys on the JU forum and the moderator on rockskulls run 24lb injectors, 68mm tb, and 3" exhaust and it does them fine. i dont even have my motor yet. i did this project while still saving. i also bought a low profile ford cobra intake elbow http://intakehoses.com/Merchant2/mer...gory_Code=CHEW

and a Reducing Insert 4" OD to 3" ID http://intakehoses.com/Merchant2/mer...egory_Code=RIS
from this cool site. i shaved it down to fit my tb and also took off 1/2 an inch so it sits lower for the hood. i'll be doing a cold intake through my fire wall and into the hood vent next to the ac air inlet on the hood.

[FRMNJJ]

any word on passing smog w/ a stroker ?

[cbremer]

any word on passing smog w/ a stroker ?

no problem here! i have the mopar performance header (CARB legal, with EO sticker) and that's the only thing visible that doesn't appear stock. passed visual no problem, and emissions were slightly above average, but still below the maximum limits.

[brokenujoint]

from what i've read over and over again, the stroker actually puts out the same or LESS emissions than when the vehicle was new. understand you now have a very clean engine. all the tolerances are tight. the visuals are the same to the common smog man. the intake will pass if its a fipk type of set up. i had a k&n cone on mine last november and i got selected to go to a stupid test only shop and i passed no prob.

ive read a few smog results on the yahoo.stroker forum and they are actually better than my tired 97 4.0 and its not running all that bad at all.

emissions isnt an issue. i thought about painting my engine the same color as my rig(red) but i then thought that that would be a red(no pun) flag to the tech to look at it closer. they couldnt see what crank i have or cam, or whatever and they dont know a 7120 head(early 90's) from a late model head and they cant tell what yr the block is because from 90-98 they are the same... its all internals my man.. nothing they can do to you on the visual. and as mentioned it will run clean at the pipe as long as its properly done!

[brokenujoint]

Well, im sick and tired of saving for the Golen motor so ive decided to take the plunge and build it up locally. I went to scottys4x4 and bought a 96xj rebuildable shortblock for 250.00 and a 94yj #7120 head for 150.00. i got it home and stripped the block bare and the head actually looks VERY nice.
I had previously bought a head and decided to port/polish it, put 2.02/1.60 valves in it and mirror finish the bowls. heres a pic of that.
I then found out that it would cost me an insane amount of money to do all that and then have to bench the head and everything else. in the end it could even kill my torque. SO i simply sold the head and with the NEW(my new) head, it will only have a very mild exh outlet port and polish, the bowls i wont touch and the valves will stay stock minus a 3 angle valve job. 200 for the total head work vs 750 for the custom done head.

i just ordered all of the parts for the 4.6 stroker and it came up to 1300.00 dollars for a block, head and ALL internal parts. machine work will be about 600.00 .. thats 1900.00 for a well build stroker vs the 3300 plus 450.00 shipping golen. wish me luck! heres the new head and block that im working on... email me for a parts list/source if interested.

[rick]

What rods are you using? I'm assuming the stock 4.2L rod and a 4.0L piston considering the cost you quote. Where did you source the crankshaft? What compression ratio are you shooting for? Are you decking the block to improve the quench height? What manifold/header are you going to run?

[brokenujoint]

Rick, the rods that i am using are - AMC 258 rods # 3180444 71-81 707 casting)

the crank was sourced locally in upland, ca and wasnt easy to source. i looked all over the net and at scottys4x4, tri-county gear. they had em but in a short block and they wouldnt part it out (of course). i found it at Superior Crankshaft. they reground it and it is in MINT condition. i paid 105.00 outright. its a 1971-1980 12 counterweight crank casting number 3214723.

the compression ratio that i'll be shooting for is 9.25:1.

I will deck the block 0.010" and shoot for a Deck Height of: 9.453"

It will be bored 0.020" over.

manifolds are: exhaust: banks header Intake: 03 4.0 intake manifold ported to 68mm to accept a 68mm dakota TB and 1/2" spacer.

hope this answers your questions

[rick]

Great info, thanks. Just trying to point out some of the other considerations that must be made when doing this, particularly when going with the 4.2L rods. My engine might be done one of these years... I'm building an aluminum head version, 9.75:1 CR, 4.0L rods, custom pistons. It's still in the machine shop. I haven't decided on the exhaust manifold vs header yet. I'm leaning toward the MOPAR header. I like the 68 mm TB, looks great!

[brokenujoint]

thats some high compression. forged pistons i hope. i want to stay away from the 91 at the pump thats why im fine with the lower compression.