350 hp naturally aspirated Inline 6

That's impressive- mid 350's-
12:1, 100 octane, 6400rpm, '99+intake, bigger TB, Banks headers, etc.

What ecu are you using to tune this?
Are you using a '99+ block with the cam thrust plate or the earlier block with the spring/pin or bolt setup?
 
To the OP. I once had your desire to hit 300+ with my 4.0. I've built numerous Jeep engines and I've ran them on dynos too. 300 is a hard to reach number for cheap. I hit 280 on the last one. 250hp is a good and RELIABLE point. I've seen Cals jeep and engine in person. Russ knows what he is doing. If you want a reliable stroker. I'll give you a baseline. 4.7, 99 intake, roller rockers with a cam of your choice. Use a 0331 head and deshroud the valves. Clean up the intake ports. Look up the numerous porting threads on the web. Clean up the bowls. Match each chamber's Cc's. Balance each part of the rotating assembly by weight. Be very precise. If you can find a good used 12 counter weight crank use that versus the newer 4cw cranks. Renix blocks are stronger. Higher Nickle content if I recall correctly. You HAVE to have a wide band o2 sensor. Adjust you afr properly. After all that, you will be very happy with your choice. You jeep will put a smile on your face every time.
 
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Here's an engine I designed which did very well. Should help you quite a bit. Read the thread for more info.
http://naxja.org/forum/showthread.php?p=245042991#post245042991

NorCalChris said:
Basically a 4.6 low buck stroker option 1

  • 96+ 4.0 block (casting # 53020569)
  • 91-95 4.0 ported head (casting # 7120)
  • 72-80 4.2l Crankshaft (casting #3214723) machining 1cm off the nose
  • 4.2l rods shot peened and balanced (707 casting?)
  • mopar performance head gasket (0.043)
  • Clevite bearings (cam, main, rod)
  • balanced Speed Pro h825cp pistons + 0.030"
  • Hastings piston rings
  • camshaft has yet to be determined. I still need to plug the numbers in on the computer (what are you running?)
  • valve springs TBD after cam
  • Yella Terra 1.6 roller rockers
  • any pushrod recommendations?
  • Mopar Performance High volume oil pump #P4529241
  • Pioneer freeze plugs
  • I haven't decided on hi flow water pump or not.
  • 99+ intake ill grind some of the casting marks away.
  • bored throttle body (any comments on Leigh Performance Machine? recently Ive heard good things about them.)
  • cold air intake (thinking about moving filter into the cowl) and keeping the stock set up for smog, unless I can find a CARB legal intake of my liking)
  • Ford injectors with a hesco regulator (anyone ever use Leighs machine's FPR?)
  • Cloyes dual roller timing set
  • Borla header? ( i prefer an equal length design. any recommendations on headers? keep in mind CARB legal)
  • 2.5inch down tube w/ 2.5 cat and spin tech muffler.
  • MSD 6AL ignition box w/ rev limiter, blaster coil, wires.
Click to expand...
FYI, there's a lot more piston options out now then there was then.
 
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CobraMarty said:
That's impressive- mid 350's-
12:1, 100 octane, 6400rpm, '99+intake, bigger TB, Banks headers, etc.

What ecu are you using to tune this?
Are you using a '99+ block with the cam thrust plate or the earlier block with the spring/pin or bolt setup?
Click to expand...


Jet renix ECU. Renix block. 7120 head with a lot of work in it (small chevy valves, beehive springs), port matched 99 intake, jeepers & creepers throttle body, 1.6:1 roller rockers. running 50 psi fp at idle, 55 at wot.

Russ Pottenger wanted to see how far we could push it and keep the thing reliable. We did have to change the motor once, due to a cracked block, but it looks like a manufacturing flaw along a casting line.. the motor still ran *great* when we pulled it out, just didn't want to hold water. ;)

We've gotta spin it up around 6K to really get the power out of it, but it starts to pull pretty good around 3700. We're running a modified TCU to bring our shift points up where we're always in the power.

I think one of the tricks to keeping these things together is run them a little rich. Most of the ones I've seen come apart looked like they leaned out and burned up a piston or two. There's no apples to apples comparison, but we seem to get around 4 mpg.
 
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What's the deal with the Jet Renix ECU? Is it programmable?
I only deal with the OBD2 HO ECUs.

'Modified TCU to bring our shift points up'. Can you share how you do this?
 
I had a Golen built 4.6L equipped with the aluminium cylinder head and a 68mm TB. It produced 325Hp at sea level on Golen's Dyno... Normally Aspirated.

At the time, you could get the cylinder head from Patriot Performance (Alabama Cylinder Heads) in two versions. Small and large valve. I went with the large valve version. It was interesting to drive...

Today, only the small valve version is available and only from Hesco. To bad really as I only paid about half of what Hesco wants these days...

If memory serves, it was 2.20 and 1.91 valves. Could be mis-remembering. Built it a long time ago.
 
CobraMarty said:
'Modified TCU to bring our shift points up'. Can you share how you do this?
Click to expand...

Are you looking for some information to steal and post as your own? Maybe your boy "flyin ryan" knows how to do that... oh wait, all he has access to is what is already laid out for him in the SCT tuning suite.
 
sidewaysstarion said:
Are you looking for some information to steal and post as your own? Maybe your boy "flyin ryan" knows how to do that... oh wait, all he has access to is what is already laid out for him in the SCT tuning suite.
Click to expand...
Not my 'boy', I don't use SCT. What an elf, merry christmas.
 
I love these threads that go all over the place. That aluminium hesco head is his entire budget, so unless you can bolt it on a stock 4.0 and hit 300 hp it's out. The only way I see hitting 300hp for $2k is a 250 shot of nitrous, and you'd probably only do that once before the pistons went through the hood.
 
zachandandy said:
The only way I see hitting 300hp for $2k is a 250 shot of nitrous, and you'd probably only do that once before the pistons went through the hood.
Click to expand...

That is the reason this thread is all over the place.
 
cherokeeproject said:
I want to stick with the 4.0 for financial reasons, I knew it was only a matter of time before someone mentioned a V8 swap, & that's just waay out of my budget. That's why I didn't bother to mention it.

Torque IS a concern with this being used for off road, but this jeep will see almost an equal amount of road time (if not more). The intention here is to generate enough power to run 4.56 or 4.10/11's with 33-35's (haven't decided yet). I know that the focus should be more on torque but that will increase respectively with the modifications.
Click to expand...

JFYI, I run 33s, 3.55s, mantrans, and a 250+k mile tired 4.0 that's been overheated badly multiple times and hydrolocked 4 times (3 that self cleared and 1 that I had to pull the plugs for.) And the previous owner probably did worse to it.

It will do 103 (gps measured) given a long enough flat road. Takes quite a while to get there, and probably would have gone faster, I ran out of balls before I ran out of throttle and road.

You don't need a stroker for this, but it does make it more fun.

Gear it right, build the stroker however you want, and run it.
 
kastein said:
JFYI, I run 33s, 3.55s, mantrans, and a 250+k mile tired 4.0 that's been overheated badly multiple times and hydrolocked 4 times (3 that self cleared and 1 that I had to pull the plugs for.) And the previous owner probably did worse to it.

It will do 103 (gps measured) given a long enough flat road. Takes quite a while to get there, and probably would have gone faster, I ran out of balls before I ran out of throttle and road.

You don't need a stroker for this, but it does make it more fun.

Gear it right, build the stroker however you want, and run it.
Click to expand...

So, I've toned it down a bit on my build (thanks to this thread) The 300+ hp isn't as much of a big deal to me anymore, before it was just a number and it still is... but I was looking for the WOW factor. Pushing the motor on 33's isn't a big problem, but if I go with 35's its a different story, and maybe in the long run the jeep might end up on 37's and I don't want to be in a situation where I need to go back and rebuild the motor to get the power that I want. I just want to build it once and build it right. I want to only change the gearing when I go up in tire size.

Ive mentioned this before and I never got a response but I know that someone out there built a 4.7L stroker with the .030" overbore. I know im making a big deal over a .1L increase but I just remember reading his write up and really liking the build so I'de like to read over it again. But for now the plan is to do a .030" overbore and shoot for a 10:1 CR and do some major head work to help it breathe. Im thinking that should put me in the upper 200's ball park.

I've already got a donor 4.0 motor out of a 98 that I plan to use. I'll slowly pick up parts here and there once I nail down exactly how I want this build done. Im thinking my budget will be in the $1500 range, which im ok with since it'll be spread out over a year or so. Once I get the build going im def. going to do a write up / build thread.
 
zachandandy said:
I love these threads that go all over the place. That aluminium hesco head is his entire budget, so unless you can bolt it on a stock 4.0 and hit 300 hp it's out. The only way I see hitting 300hp for $2k is a 250 shot of nitrous, and you'd probably only do that once before the pistons went through the hood.
Click to expand...

Nitrous is def out of the question, and I wouldn't say that its the ONLY way to hit the 300hp mark.
 
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