New video featuring Newcomer Racing. To me, this proves the 4.0 isn't worth the money for bolts on's: either go with boost, or LS swap lol
4.0 Dyno Comparisons: Newcomer Racing
- Thread starter Alex0413
- Start date
Watched it out of geekiness. 
Agree on the conclusion. Just not mess with the 4.0 since you have nothing material to gain. Not to mention you may impact it’s best characteristic, reliability.
Agree on the conclusion. Just not mess with the 4.0 since you have nothing material to gain. Not to mention you may impact it’s best characteristic, reliability.
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Very few NA engines in history have ever responded well to bolt-ons...
FI engines are the other hand response very well. I recall one of the popular hot rod magazines at the time, perhaps even "Hot Rod" itself, did a "bolt-on challenge". They tested a handful of cars popular at the time, including one of the staff members' turbo AWD Eclipse. It held the record for "HP/$ investment" for a long, long time. I recall one of the worst (in the "follow up" article many years later) was the Honda S2000, where it took something like $900 for +4HP...
FI engines are the other hand response very well. I recall one of the popular hot rod magazines at the time, perhaps even "Hot Rod" itself, did a "bolt-on challenge". They tested a handful of cars popular at the time, including one of the staff members' turbo AWD Eclipse. It held the record for "HP/$ investment" for a long, long time. I recall one of the worst (in the "follow up" article many years later) was the Honda S2000, where it took something like $900 for +4HP...
Interesting but then I don’t get why the S2000 is a sooo common platform for upgrades…
the S2000 in stock form never responded well to bolt ons. It was very common for 95% of the aftermarket intakes on that motor to LOSE power on the dyno instead of gain.
chasing N/A power is always a more expensive exercise than boost. Especially when you're not talking big-block V8s. IMO a reasonably sized turbo on a 4.0 would be tremendous fun Like a solid 250whp, tops. Don't need any more than that. The torque figure at that range would be north of 300ft-lbs anyway.
So re the S2000 I understand that it is used a platform but with the additions of turbos. Makes sense, as especially this engine is diamond when it comes to hp/L. 
I think it was like the Miata, but with better looks, a nicer interior (even if just marginally so), and "Honda reliability"... a fun to drive roadster and just cheap enough for many to get into. The 9000 RPM rev-limit was also fun. It also had some on-screen time when it was just coming into the mainstream, which I'm sure added to it's popularity (which is also why my dreams of an original 2JZ Supra are wanning).
That said, I think most folks know that the S2000 is a "9/10ths car" (meaning it's at about 9/10 of the platforms capability right from the factory) and is generally a poor car for serious power or track days (even the Honda bois agree that power gains are minimal and that reliability should be the focus). This is in contrast to the Miata, which actually has some decent options and capability (thanks to aftermarket). I couldn't find the article I was thinking of, but this one reflects the same sentiment. At the time of this article, the cost of +1hp was more than the cost of an oz of gold and it still was a 14-second car in the 1/4 mile (not that it was ever intended as a 1/4 mile car) https://www.caranddriver.com/reviews/a15138325/mugen-s2000-road-test-review/
Of course with boost, that becomes something different
That said, even with boost, the cost quickly rises across the platform and other weak-links become evident. I haven't spent any personal time playing with an S2000 but a few friends did back in the day. After many iterations and "power levels", all of my friends dropped the platform for something else.
The bolt on do very little but the stroker hp would be nice. I live in California though and I have not researched the emission compliance aspect of a swap. I know every year it get tougher. A small LS can be picked up for almost nothing but that would require replacing everything.
My experience on engine-swapped Jeeps is limited to a 4.7 swapped TJ and a 5.7 swapped 4 JKU, where ai ran shotgun on both. So not a lot.
However, I really agree with your above statement which makes me wonder why there are more 4.7(HO) swaps in TJs.
As a recent owner of a 4.7HO WJ I guess it be a veeeery nice and not so expensive (?) swap to have a TJ with a 265hp V8.
I agree. My Golen 4.6L stroker with a 62mm TB and stock '97 intake and tune makes 24% more HP and TQ than the stock 4.0L with no other changes on the same chassis dyno. Not breathtaking but since the displacement bump is only 15%, perhaps not terrible either. By the way, don't fixate on the absolute engine dyno numbers. They are NOT comparable to the chassis dyno or even the stock Jeep numbers.
How do you like the 4.6 ? I have been kicking that around just haven’t done to much research on it. Right now I am concentrating on making my Jeep lighter.
I do like it. Its stronger than stock, for sure but feels the same (like a jeep straight six). Not a transformation like a totally diff engine. And I really enjoyed the swap. It was my first. Its a very straight forward, bolt in affair. If you need a new 4.0L or just want to get your feet wet with a simple swap, go for it. If you want huge power, then do the V-8 thing. I have dyno results and lots of details on the swap in my build thread(https://wranglertjforum.com/threads/woodrow’s-97-green-tj-moderate-build.51602/page-5)
OP
Dude, that just hurts….
Hemi swaps ain't cheap, but they sure are sweet! Hope you've been well Jeff!!
OP
Yeah the baseline numbers he's putting down with the 4.6L stroker are pretty awesome! I wish they were able to show the torque curve at a lower RPM. If the area under the TQ curve is up 24% in lower RPM, that's HUGE !
The cost of bolt-on's for the 4.0 and the gains we're seeing just don't seem worth the cost. Especially considering most of the gains are at high RPM's , where they engine is seldomly utilized.
I boosted my 4.0, and the gains are night and day difference, and only have about $2k in it. Turbo kits can easily be fabricated for these engines too, you see it done a lot more with the XJ crowd for cheap.
Brianj5600
TJ Expert
https://wranglertjforum.com/threads/woodrows-97-green-tj-moderate-build.51602/page-5#post-973066
I looked at the dyno sheets in your build thread and there is a lot of room for improvement. Timing and A/F is off by good bit. That is probably why you are not getting the results you expected. Timing is low and .94 lamda is more than a little lean at WOT. .94 lamda is 13.9 A/F ratio and it should be closer to 12.5 A/F. The timing is the stock timing tables. The 1st point at 2428 rpm has 18.5 advance and my tune has 23 adv, 2nd point at 3831 has 21.5 adv mine has 31adv and the 3rd point at 4674 has 26.5 adv and mine is 31 adv. Golen built you a good motor, but it is held back by a factory tune. Do you have tuning software? Wideband O2?
PS, with those cranking pressures I would not be surprised if that motor would run fine on 87 octane.
Thanks for looking it over. Tuning is one of many topics on which I am uneducated. I‘ve talked to Chad Golen pre and post purchase. He neither encouraged nor discouraged tuning it but said repeatedly it’s designed to run well with a stock tune. He also said on their superflo engine dyno they use a stand alone Holley EFI and 36 degrees of advance. A tuner I know in my area and Ryan Hogan of Flyin Ryan were both willing to work on the tune. But while they both agreed there were likely some gains to be had under the curve, they also thought improvement would probably be less at WOT. They also both said that 36 degrees of advance, while workable on an engine dyno, was not realistic on the street. Ryan further said 26 to 27 degrees was more the mark and he hadn’t a stroker go over 28. I may still ask one of them to tune it at some point, but I really do enjoy the improvement in drivability as it is and so tuning has fallen down my list of priorities for now.
Flying Ryan’s stock tune “cleaned up” how my stock engine performs if that makes sense. I’d absolutely pay him for a tune if I had a stroker.
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Brianj5600
TJ Expert
This is a stock timing table.
Timing is very, very conservative under medium to high load. When you need more power the stock table is reducing advance as low as 16.5 degrees with modifiers. At highway speeds the stock timing table on my Jeep would start pulling timing as load increased and it seemed to not make any more power past half throttle. The additional advance helped considerably above 60 MPH. The changes I made to timing is all in the lower right. I added more than 10 degrees in the last column above 2240 RPM and blended the cells back to the left to the highest advance of the stock tune.
Timing is very, very conservative under medium to high load. When you need more power the stock table is reducing advance as low as 16.5 degrees with modifiers. At highway speeds the stock timing table on my Jeep would start pulling timing as load increased and it seemed to not make any more power past half throttle. The additional advance helped considerably above 60 MPH. The changes I made to timing is all in the lower right. I added more than 10 degrees in the last column above 2240 RPM and blended the cells back to the left to the highest advance of the stock tune.