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HP/TQ gains?
Posted: August 10th, 2012, 9:28 pm
by ftpiercecracker1
Its been quite a while since i have posted on hear, but my stroker motor will be done within the month and i am desperately trying not to count my chickens before they hatch

.
What should I be expecting in Hp/Tq gains? I will be spending about 2500 when its all said and done. nothing crazy, like aluminum head or all forged interals. But it will have some decent flow work done, port, polish, 4 angle grind and be tuned on a dyno to
absolute perfection.
would 250hp and 250tq be expecting to much

? This would be to the crank
thanks guys

Re: HP/TQ gains?
Posted: August 11th, 2012, 1:27 am
by Cheromaniac
My stroker puts out near 250/310 at the crank without anything fancy in it so it's an achievable goal.
Re: HP/TQ gains?
Posted: August 11th, 2012, 3:14 am
by CobraMarty
What else is being done? What year? intake? TB? renix? injectors? headers? Cam? porting? Compression?
Stock 190HP/230TQ ->> stroker 4.6L +15%, cam+5% == 230HP/280TQ
Can't wait for the dyno. I would expect to see under 250cHP and well over 250cTQ probably closer to 275-280+. The heads flow poorly for a 4.0L and are that much more deficient on a 4.6L. The 'stroker' is a torque monster.
I see a HP/TQ 'prediction' pool coming in a month.

Re: HP/TQ gains?
Posted: August 11th, 2012, 9:12 am
by ftpiercecracker1
CobraMarty wrote:What else is being done? What year? intake? TB? renix? injectors? headers? Cam? porting? Compression?
Stock 190HP/230TQ ->> stroker 4.6L +15%, cam+5% == 230HP/280TQ
Can't wait for the dyno. I would expect to see under 250cHP and well over 250cTQ probably closer to 275-280+. The heads flow poorly for a 4.0L and are that much more deficient on a 4.6L. The 'stroker' is a torque monster.
I see a HP/TQ 'prediction' pool coming in a month.

to answer your question:
Year: 1990
Intake: port and polish like hell also 90, should i find a different one?
TB: stock 90, bore out? or find another?
Renix: yes
Injectors: not yet calabrated
Header: stock, does it matter that much?
Cam: mild, something happy medium
Porting: everything, lots of head work, but no oversized valves
Compression: probably be around 8.7-1 and 9-1
and you can bet your butt on that 'prediction' pool

Re: HP/TQ gains?
Posted: August 11th, 2012, 11:26 am
by Muad'Dib
Its hard to say without knowing your exact build. Just the stroker alone will not get you up to 250hp. This will depend on the bolts ons you may also have. Every engine is different though.
I built mine pretty good.. but i havent dynod it yet. I think i will be lucky to have around 250 at the crank.
Re: HP/TQ gains?
Posted: August 12th, 2012, 10:30 am
by Cheromaniac
Muad'Dib wrote:I think i will be lucky to have around 250 at the crank.
I managed to achieve that because I have all the bolt-on goodies and I ported the head (7120). With an unported HO head plus bolt-ons you're only going to get 225-230hp, and with an unported Renix head it'll be 215-220hp. Take away the bolt-ons and you're down to only 190 crank hp from a poor man's Renix stroker.
Re: HP/TQ gains?
Posted: August 12th, 2012, 10:57 am
by CobraMarty
Cheromaniac wrote:Take away the bolt-ons and you're down to only 190 crank hp from a poor man's Renix stroker.
What was the HP and TQ of the stock Renix?
What year and motor is he starting with? What is his stock HP and TQ?
Re: HP/TQ gains?
Posted: August 12th, 2012, 5:51 pm
by ftpiercecracker1
my motor, factory made 177 hp and 269 ft/lbs of tq, according to "dino's" web page
MY motor is a plane jane Renix block, head, intake, and tb.
block will be bored .035 over, head will have lots of work, intake will be ported and polished, and TB may be bored as well.
Re: HP/TQ gains?
Posted: August 13th, 2012, 2:31 am
by Cheromaniac
ftpiercecracker1 wrote:my motor, factory made 177 hp and 269 ft/lbs of tq, according to "dino's" web page.
The factory quoted outputs for the Renix 4.0 XJ were 177hp @ 4500rpm and 224lbft @ 2400rpm.
Re: HP/TQ gains?
Posted: August 13th, 2012, 3:46 pm
by casual
All in all you should be ditching the rnix head! Find a good 7120 cast head!
Clean & mildly port it. Run the original renix cam..87-95 single pattern cam. But run it at -4 or -2* vthe factory -8. The single pattern cam in stock form will hold power to around 6500rpm...we don't rev that high, so if you advance the cam then it will move the power band a little lower. At -4* your power band should be 2000-5800rpm. Stock is 2400-6200..Possibly run it at -2* or even straight up.
This will save you some cash while still picking up gains! Shoot stock 4.0 guys should be doing this also.
Header..yes the stock renix log manifold sucks! Pick up a APN header for around 150..deffinetly need a bored throttle body. Look at using 24lbs injectors.
Re: HP/TQ gains?
Posted: August 13th, 2012, 6:12 pm
by ftpiercecracker1
cant find much less afford the 7120 head
I dont have the log stlye manifold, i have the 2 sets of three go near straight down into a collector and then out
i will let my guy know about the cam, i do love saving money
TB bored to what mm? I guess that will depend on my needs.
I already told my guy we would probably need larger injectors, but we arent far enough into the build to worry about that.
Re: HP/TQ gains?
Posted: August 13th, 2012, 6:32 pm
by shawnxj
if you can't find a 7120 get an 0630 they're basically the same just need to add a temp sensor to the 0630. where are you located? every junk yard i go to has them by the dozens for about $50 each
Re: HP/TQ gains?
Posted: August 14th, 2012, 7:27 am
by Cheromaniac
ftpiercecracker1 wrote:cant find much less afford the 7120 head
There should be a plentiful supply of 0630 heads in the junkyards so grab one and port it. You can also find '99+ intake manifolds pretty cheap and they're a good addition if you mildly port the injector bosses. Finally, a 62mm bored HO TB will give you a snappy throttle response without being oversensitive.
As far as cams go, keep the one you already have and just replace the lifters.
Re: HP/TQ gains?
Posted: August 14th, 2012, 8:55 pm
by ftpiercecracker1
Thanks for all the pointers guys, but unfortunately and i guess unbelieveably as well NONE of the junkyards in my area, there are 4 of em, have either head

. Even more not a sinle place has even one cherokee. They've got a few ZJs and GRAND cherokees but absolutely zero XJs.
I can already hear some of you calling
as for my local, middle TN, Murfreesboro area
Re: HP/TQ gains?
Posted: August 14th, 2012, 11:24 pm
by Cheromaniac
The head from a 4.0 ZJ and the intake manifold from a 4.0 WJ would do. You can find a 62mm TB in ebay.