PEAK PUTTERS

Has anyone installed one? Any after thoughts? What octane gas are you running? Anyone that has not done it have any thoughts or opinions? 4.6 or otherwise. My 4.0 is getting tired and noisy.

I'm Scumby damm it!

I've driven one and was impressed with the power but it was also a 4.88/5sp/35" rig apposed to my tired 4.0/auto/3.07.
He had an RV cam and 5.0 injectors but the biggest thing is read up on the timing. 4.0s time differently and it took about 3 people before the distributor was moved one tooth, and WOW what a difference that made.

I've been looking at them off and on in preparation for when my 4.0 explodes.

Was originally thinking about buying one from Golen, but after my recent excursions into engine tinkering I might try and build one myself to save some cash.

I think you can set them up for whatever octane you want to run, though most of the pre-built ones have enough compression that you're forced to stick with 91.

A buddy of mine in vancouver stroked his in the cherokee, he was like a kid in the candy store after he got it on the road, he was running 37's and 4.88 I think with an auto. He definately would not have just a 4.0 again.

My uncle, who drives the little red flatty, has had a stroker in his Cherokee (tow pig) for quite some time. I am not sure, but I think he has nearly 200k on the stroker now. He has been towing his service trailer around with it for several years, said the stroker really helped the fuel mileage for towing the trailer and had plenty of power.

If you stick with a large dished piston and make the squish clearance nice and tight (0.030") while keeping within the 9.5:1 ratio, you should be perfectly fine for octane tolerance. A tight squish clearance will benefit you octane tolerance, fuel mileage, and overall power output. Most of the crate engine builders dont care about this at all.

Your cam selection will also have a huge effect on overall power and octane tolerance.

One of the reasons I'm thinking of the stroker is because I have a tentrax trailer I'd like to tow without issues. I'm not an engine guy but have beenreading about octane requirements but don't really understand the squish thing. I'm running 37's and 4.56's with a 6 speed. I am also considering the Golen stroker.

Oops double post

scumby wrote:One of the reasons I'm thinking of the stroker is because I have a tentrax trailer I'd like to tow without issues. I'm not an engine guy but have beenreading about octane requirements but don't really understand the squish thing. I'm running 37's and 4.56's with a 6 speed. I am also considering the Golen stroker.

Squish clearance: distance between piston and head at TDC. A lot of guys think that shaving the head will tighten this, but are wrong. You must deck the block to move the head closer to the piston.

Why for: at TDC, this clearance creates an instantaneous turbulance in the combustion chamber, making the (already ignited) mixture burn faster and more thoroughly, which translates into more power and slightly better combustion efficiency. It will increase the octane tolerance because it causes more even heat distribution in the combustion chamber, reducing pre-ignition. Pre-ignition is where the fuel erratically ignites from compression heat instead of from the spark plug.

On the Jeep head, you really need to have it tight to make it effective, because they dont leave much of a squish area. I am running 0.025" on my 2.5. If that is too close for comfort, you should at least get it down to 0.030". Dont worry about piston to valve contact, the Jeep head has a TON of room between them.

On a race engine, you basically want to make the squish clearance as tight as possible without contact between piston and head/valves. When you pull one of these apart after many hours of use, you will see clean areas (no carbon buildup) on the piston and head where they nearly contact.

i have done 3. and for the money there worth it. my xj i did my self with a golden kit. and ported the head my self. ended up using a apex safc to controll fuel running mustang 24lb injectors.. was a tq monster but still was not enough so i picked up a eaton m90 supercharger and removed my ac unit and installed that with a 8lb pully and mustang 35lb injectors. it was a fun rig after that.. i ran prem fuel in all cases.

my first yj i bought a golden eagle bottom end and did the head my self. with 505 performance cam and roller rockers. just simple bolt ons intake/tb spacer/exhaust and there tuned ecu. ran my 60's down the road nice no issues.

the third one i bought with it. complete motor drop in with just a header and cold air. you can tell the diffrence in bottom end. and mid range.. dont like the top end so much

most of the 4.6 off the shelf are suppose to be around 350hp. ive seen turbo versions hit 500+ and yes building it your self is going to save.. and you tend to take it eayser on the motor lol.

some things i found out.
head studs are a good easy thing to do while you are there
dont use a high psi high vol oil pump. high psi low vol is the way to go. or you will have oiling issues down the road.
head work is going to help with power. port polish and a valve job.
the jeep will run with mustang 24ln injectors on its own but tuning brings out the power.
you can hand port the intake manifold and thottle body yourself
and gasket match
good cam shaft.. the stocker is pretty weak.
ive had good help and support with 505 performance
and boost is always a option. the m90 supercharger is cheap and easy to adapt. tons of room for a home brew turbo.

Toolegit86 wrote:i have done 3. and for the money there worth it. my xj i did my self with a golden kit. and ported the head my self. ended up using a apex safc to controll fuel running mustang 24lb injectors.. was a tq monster but still was not enough so i picked up a eaton m90 supercharger and removed my ac unit and installed that with a 8lb pully and mustang 35lb injectors. it was a fun rig after that.. i ran prem fuel in all cases.

my first yj i bought a golden eagle bottom end and did the head my self. with 505 performance cam and roller rockers. just simple bolt ons intake/tb spacer/exhaust and there tuned ecu. ran my 60's down the road nice no issues.

the third one i bought with it. complete motor drop in with just a header and cold air. you can tell the diffrence in bottom end. and mid range.. dont like the top end so much

most of the 4.6 off the shelf are suppose to be around 350hp. ive seen turbo versions hit 500+ and yes building it your self is going to save.. and you tend to take it eayser on the motor lol.

some things i found out.
head studs are a good easy thing to do while you are there
dont use a high psi high vol oil pump. high psi low vol is the way to go. or you will have oiling issues down the road.
head work is going to help with power. port polish and a valve job.
the jeep will run with mustang 24ln injectors on its own but tuning brings out the power.
you can hand port the intake manifold and thottle body yourself
and gasket match
good cam shaft.. the stocker is pretty weak.
ive had good help and support with 505 performance
and boost is always a option. the m90 supercharger is cheap and easy to adapt. tons of room for a home brew turbo.

have you had any trouble tuning any of them?

the stock ecu runs them pretty well.. even with the mustang injectors. the apex safc will only control fuel.. thats it. so wide band is needed. wiring it up is pretty easy just basically a piggyback for the stock ecu..

505 you send your ecu to them with you list of modds. and they reflash your ecu and send it back. works out great.

Toolegit86 wrote:the stock ecu runs them pretty well.. even with the mustang injectors. the apex safc will only control fuel.. thats it. so wide band is needed. wiring it up is pretty easy just basically a piggyback for the stock ecu..

505 you send your ecu to them with you list of modds. and they reflash your ecu and send it back. works out great.

what is apex safc?

basically a dash mounted fuel controller piggy back to the factory ecu. basically set up for the hondas and dsm's its pretty easy to wire up takes some time to get use to it..

http://www.apexi-usa.com/store/electron ... ement.html

dont freak out on that price lol.. thats a new version. there are many out there.. usually pick them up off craigslist or ebay for 100$ if that.