Jump to content

Welcome to NCLR - Northern California Land Rover Club
Register now to gain access to all of our features. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more. This message will be removed once you have signed in.
Login to Account Create an Account
Photo

engine performance

- - - - -

  • Please log in to reply
25 replies to this topic

#1
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

OK, it's not a popular topic for Rover drivers, but let's talk engine performance.

 

My D1 has a 4.6 in it with 4.0 intake/exhaust  to make it look stock.   It has adequate performance off-road, but on the highway is where I'd like a little more.  It's just week.  It feel like trying to run it over 3000 rpm, say a down-shift to pass or climb a hill, is almost pointless as I get a lot of wheezing noise from the exhaust but little else.

 

So what are my options to improve the highway performance on these motors?  I've heard from Dan somebody does some ECU tuning but don't know who or what.  Injectors?  Small improvement in cam?  Headers?  Port match the intake and exhaust (it looks horrible judging from some of the spares I've got)?

 

The engine itself has less than 40K on it.  I suspected the cats might be getting clogged up based on the wheezy noise at higher RPM but a back pressure test by a local shop says no, they're not a restriction (I find this somewhat hard to believe but that's the result).  The rest of the exhaust is a single Flowmaster muffler - certainly not a major restriction.  I don't have a lot to compare it to and the rest of the truck is so far from stock it's hard to compare with others but I feel like I'm leaving something on the table; that there's more to be had from an otherwise good running 4.6.


  • PaulD likes this

Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#2
PaulD

PaulD

    NCLR Club Member

  • NCLR Club Member
  • PipPipPip
  • 211 posts
  • Templeton, CA
  • 1993 RRC LWB
  • 1991 RRC -- Caught Fire
  • 1967 NADA 109 - SOLD
  • 1967 Series IIA 88 - SOLD
  • 1964 Series IIA - Stolen

Part of the highway issue might be b/c you are pushing tall rubber. The lever arm/gear ratio is working against you there.

 

--Paul


'93 LWB
2" RTE Springs, GDE w/8K winch, Disco axles, Viair, Dura-Tracs, & Asst'd grille badges

12e11964-24f6-4630-a08f-5758456bc143.jpg


#3
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

Of course, but I'm geared to accommodate that.  My RRC has 33" tires and stock gearing so that's understandably doggy.  This truck has 35" tires but is geared to run nearly 3000 rpm at 70 mph so gearing isn't the issue.

 

The larger tires certainly mean increased rolling resistance and more unsprung weight which hurt performance as does the sprung weight of the cage, bumpers, winch, armor, etc, though that's balanced against the reduction of weight from the removal of the rear of the truck and it's heavy glass and the rear interior (seats, carpets, sound deadening, etc) so though I haven't weighed it I don't think overall weight is significantly different than stock.

 

I really need a base-line to compare it to but don't have that.  I have a stock D1, but it's a parts truck.  It runs and drives but hardly something I'd call 'good'.  I had the 4.2 in a SWB RRC for a while but didn't drive it enough to really get a good feel for it.  I have a stock 3.9 in the other RRC but as mentioned above it's got stock gearing with a much larger tire so completely out of step.  None of them are a 4.6 like the D1 has, and none of them are really comparable.


Edited by DHappel, 22 October 2017 - 10:22 AM.

  • PaulD likes this

Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#4
PaulD

PaulD

    NCLR Club Member

  • NCLR Club Member
  • PipPipPip
  • 211 posts
  • Templeton, CA
  • 1993 RRC LWB
  • 1991 RRC -- Caught Fire
  • 1967 NADA 109 - SOLD
  • 1967 Series IIA 88 - SOLD
  • 1964 Series IIA - Stolen

You need a dyno. :D :D :D

 

Maybe try driving Nathan's 4.6 RRC next time you see him?

 

--Paul


'93 LWB
2" RTE Springs, GDE w/8K winch, Disco axles, Viair, Dura-Tracs, & Asst'd grille badges

12e11964-24f6-4630-a08f-5758456bc143.jpg


#5
Elherbinator

Elherbinator

    Navigator

  • NCLR Club Member
  • PipPip
  • 69 posts
  • San jose
  • Discovery 2

Of course, but I'm geared to accommodate that. My RRC has 33" tires and stock gearing so that's understandably doggy. This truck has 35" tires but is geared to run nearly 3000 rpm at 70 mph so gearing isn't the issue.

The larger tires certainly mean increased rolling resistance and more unsprung weight which hurt performance as does the sprung weight of the cage, bumpers, winch, armor, etc, though that's balanced against the reduction of weight from the removal of the rear of the truck and it's heavy glass and the rear interior (seats, carpets, sound deadening, etc) so though I haven't weighed it I don't think overall weight is significantly different than stock.

I really need a base-line to compare it to but don't have that. I have a stock D1, but it's a parts truck. It runs and drives but hardly something I'd call 'good'. I had the 4.2 in a SWB RRC for a while but didn't drive it enough to really get a good feel for it. I have a stock 3.9 in the other RRC but as mentioned above it's got stock gearing with a much larger tire so completely out of step. None of them are a 4.6 like the D1 has, and none of them are really comparable.

Just out of curiosity, what gears are you running?


Sent from my iPhone using Tapatalk

#6
Jethro

Jethro

    NCLR Club Member

  • NCLR Club Member
  • PipPipPip
  • 710 posts
  • Roseville
  • KK6ZBT
  • '11 LR4
  • '96 Discovery

OK, it's not a popular topic for Rover drivers, but let's talk engine performance.

My D1 has a 4.6 in it with 4.0 intake/exhaust to make it look stock. It has adequate performance off-road, but on the highway is where I'd like a little more. It's just week. It feel like trying to run it over 3000 rpm, say a down-shift to pass or climb a hill, is almost pointless as I get a lot of wheezing noise from the exhaust but little else.

So what are my options to improve the highway performance on these motors? I've heard from Dan somebody does some ECU tuning but don't know who or what. Injectors? Small improvement in cam? Headers? Port match the intake and exhaust (it looks horrible judging from some of the spares I've got)?

The engine itself has less than 40K on it. I suspected the cats might be getting clogged up based on the wheezy noise at higher RPM but a back pressure test by a local shop says no, they're not a restriction (I find this somewhat hard to believe but that's the result). The rest of the exhaust is a single Flowmaster muffler - certainly not a major restriction. I don't have a lot to compare it to and the rest of the truck is so far from stock it's hard to compare with others but I feel like I'm leaving something on the table; that there's more to be had from an otherwise good running 4.6.

So I know the low range TC was changed...I'm wondering if you have a changed high range gear too? It's common for people to get rid of the 1.2 in favor of the 1.4 or 1.6 out of defenders from what I read on some forums. When increasing tire size helps climb hills but kills freeway speed.

Is that a possibility?

Sent from my Nexus 9 using Tapatalk

#7
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

It's not a gearing thing. 

 

Here's the key - I'm running almost 3000 rpm on the interstate.  (If I get a chance I'll go out today and get a precise number)

 

How I get to 3000 rpm at a specific speed can be achieved by changing the gearing in the transmission, the transfer case, the axles, or the tire diameter.  Doesn't really matter, the end result is the same.  I could have a 20:1 transfer case so long as the axles were geared to match.  (in theory at least)

 

So let's not worry about gearing - I've got plenty of gearing.   

 

I'm looking for engine performance; particularly at the higher end of say 3000-4000 rpm where this engine just feels flatter than I'd expect.


Edited by DHappel, 23 October 2017 - 10:20 AM.

Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#8
JFuller

JFuller

    NCLR Guest

  • NCLR Guest
  • PipPipPipPip
  • 1,103 posts

i think you need this

 

http://www.roverware...8-1-845848-8-2/



#9
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

So just for reference, the axles are 4.10s and I just took some measurements using a GPS and the Scanguage for RPM

 

50 mph 2100 rpm

60 mph 2550 rpm

70 mph 2960 rpm

 

FWIW, the speedo is basically correct.  It reads 1 or 2 mph low which is closer than many stock vehicles I've owned.  Tires are 35" MTR/Ks, though they have some wear on them.

 

If somebody wants to check the rpm/speed ratio for a stock truck that would be fine.  I bet you'l find it works out that my over-all gearing is similar or shorter than stock, meaning gearing shouldn't be an issue.

 

I'm not trying to build a hotrod, I just feel like I'm leaving a bit on the table compared to other 4.6 trucks I've been around.


Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#10
Jethro

Jethro

    NCLR Club Member

  • NCLR Club Member
  • PipPipPip
  • 710 posts
  • Roseville
  • KK6ZBT
  • '11 LR4
  • '96 Discovery

It's not a gearing thing.

Here's the key - I'm running almost 3000 rpm on the interstate. (If I get a chance I'll go out today and get a precise number)

How I get to 3000 rpm at a specific speed can be achieved by changing the gearing in the transmission, the transfer case, the axles, or the tire diameter. Doesn't really matter, the end result is the same. I could have a 20:1 transfer case so long as the axles were geared to match. (in theory at least)

So let's not worry about gearing - I've got plenty of gearing.

I'm looking for engine performance; particularly at the higher end of say 3000-4000 rpm where this engine just feels flatter than I'd expect.

Gotcha, so definitely be interesting to ride in a D2 with the 4.6 gems engine and see how it handles.

But wondering about the trick with swapping to Ford injectors.

Sent from my Nexus 5X using Tapatalk

#11
SLOHybrid

SLOHybrid

    Driver

  • NCLR Club Member
  • PipPipPip
  • 949 posts
  • SLO
  • 95 RRC 25th 4.6
  • 04 L322
  • 87 RRC
  • 94 4.6 RRC LWB CRAWLER

Don,, I have a 4.6 that I built in my 95 25th.. it has stock compression and uses a Crower 50230 cam High end RPM..  it also has a RPIV8 ECU upgrade from "Jolly old" it has the 5.0 mustang/t-bird injectors too (not sure it made a difference) it has stock exhaust manifolds and cats merging into a full Borla exhaust.  Spark is stock @ the moment. My car is pretty quick for a 6000 pound truck on 33's... I am going to upgrade to 4:14 R&P when I can afford ARB's.  

 

I have built a 95 3.9 in the past and installed a 50229 (low end torque)cam in it and it too was impressive.

 

I would suggest you change the cam myself and get the end plate machined to fit the cam so you won't have "end play" like I have in mine.  This will really help!  Also I know ECU upgrades are useless on a normally aspirated car but I think it helps with the fuel requirements :D oh! on that subject it get's approx. 12mpg.

 

Happy to help if you need more ;) 


  • DHappel, alpaca and Jethro like this

NCLR 093

Traversing Defense Mine Waterfall
http://www.youtube.c...h?v=JqczzhsWOh8


#12
alpaca

alpaca

    NCLR Club Member

  • NCLR Club Member
  • PipPipPip
  • 208 posts

My 4.4 RR Sport is not that quick either  (6000lbs and 300BHP is not enough) - best fix for that problem is to get the supercharged engine :) 


  • RedRover likes this

[SIGPIC][/SIGPIC]
2006 RRS
2002 911

2003 E46
2008 C300

2015 Cherokee


#13
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

Don,, I have a 4.6 that I built in my 95 25th.. it has stock compression and uses a Crower 50230 cam High end RPM..  it also has a RPIV8 ECU upgrade from "Jolly old" it has the 5.0 mustang/t-bird injectors too (not sure it made a difference) it has stock exhaust manifolds and cats merging into a full Borla exhaust.  Spark is stock @ the moment. My car is pretty quick for a 6000 pound truck on 33's... I am going to upgrade to 4:14 R&P when I can afford ARB's.  

 

I have built a 95 3.9 in the past and installed a 50229 (low end torque)cam in it and it too was impressive.

 

I would suggest you change the cam myself and get the end plate machined to fit the cam so you won't have "end play" like I have in mine.  This will really help!  Also I know ECU upgrades are useless on a normally aspirated car but I think it helps with the fuel requirements :D oh! on that subject it get's approx. 12mpg.

 

Happy to help if you need more ;)

Well.....now we're onto something.  I looked up the cam spec and it's a Crower 50229 with Crane hyd lifters.  

 

I really need to drive a stock 4.6 truck (maybe one with some mods) to get a feel for it as a reference point but my gut is telling me two things:

1-even with the 'low rpm/high torque' cam, I would expect it to pull a little better on top.  I feel like it's lazier than a stocker should be

2-it really sounds like (and this would fit my issue) the exhaust is restricted however a local shop measured no significant backpressure.  It may be that I shouldn't trust them, but I walked in willing to spend money and they talked me out of it so...? 

 

I have no idea how to go about making any tweeks to the ignition with the 4.6.  It's not like I can drop in a new coil or bump the timing a few degrees by getting out the timing gun and twisting the disty.

 

Injectors are stock so far as I know; as is the ECU.  Tell me more about these options.... 


Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#14
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

I have found a bookmarked RPI Engineering's site (v8engines.com).  Now I have some reading to do!

 

I really know very little about these engines and of course they are trying to sell a product, but I can see there may be some money spent with these guys.

 

<edit>

In digging around a bit I see their site is rather old and hasn't been updated in years.  Not sure if they are even still in business at this point.


Edited by DHappel, 23 October 2017 - 03:23 PM.

Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#15
SLOHybrid

SLOHybrid

    Driver

  • NCLR Club Member
  • PipPipPip
  • 949 posts
  • SLO
  • 95 RRC 25th 4.6
  • 04 L322
  • 87 RRC
  • 94 4.6 RRC LWB CRAWLER

go to RPIV8.com... I have spare 14cux's if you need to send it

 

 

I think it is them that has the hot spark ICM too

 

 

 

the injectors are EV1 gen 5.0 19lb 

 

https://www.ebay.com...s=Model:Mustang


Edited by SLOHybrid, 23 October 2017 - 03:19 PM.

NCLR 093

Traversing Defense Mine Waterfall
http://www.youtube.c...h?v=JqczzhsWOh8


#16
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

Injectors are cheap - order placed.

 

I've sent an email asking about ECU work.  We shall see what comes back.  I was wondering to myself if there wouldn't be an issue with the stock 4.0 ECU running the 4.6.  It sounds like they can deal with that and still get it past smog.  The ignition upgrade may be more difficult to sneak past if it's 'visible'.


Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#17
lithium1330

lithium1330

    NCLR BOD Member

  • NCLR BOD Member
  • PipPipPip
  • 511 posts
  • San Jose
  • KM6FDG
  • Defender 90 NAS #0032

The 4.0 GEM ecu can manage the 4.6. I think East Coast Rovers does do some tuning when they upgrade Defensers to 4.6. But there are plenty of 4.6 swaps running unchanged. i can’t remember if your D1!is automatic or manual. The transmission is actually a weak point for most 4.0 to 4.6 swap. The ZF4HP22 that came with the 4.0 runs at the upper end of the transmission capability, and a 4.6 pushes over the published transmission torque limit by about 30ft-lbs, IIRC. Ashcroft sells a beefed up 4PH22 with ZF4PH24 parts. 

 

Anyways, if you’re interested in learning more about the GEM V8’s engine management ...this may be of interest. 

http://www.gomog.com...GEMSbyPoole.pdf


Chris

#18
psykokid

psykokid

    SCLR Club Member

  • SCLR Club Member
  • PipPipPip
  • 490 posts

I think that on the GEMS ecu there is a byte you can re-write with something like a test book, rovacom or similar that changes the map from the standard 4.0 to the 4.6 map.

 

I found a program that someone wrote on discoweb that you can use with a couple of certain OBD bluetooth adapters that will allow you to reset the adaptive values in the ECU. Prior to that program coming around the only way you could reset the adaptives in the ECU was with a test book or similar. It's good if you have done a tune up or replaced several sensors on the engine. Engine will usually run a bit rough at first as it goes through the re learning process, but smooths out pretty quickly. The guy wrote binaries that will run on Mac and PC. Oddly enough, I wasnt able to get the PC version to work so I tried with my wifes macbook and I was able to rewrite all the adaptives.



#19
DHappel

DHappel

    NCLR Trip Ambassador

  • NCLR BOD Member
  • PipPipPipPipPipPip
  • 6,091 posts
  • Walnut Grove, CA
  • KK6TBH
  • '07 LR3 with stuff
  • '96 D1 Roadster
  • '94 RRC
  • '96 D1

So here's what I got back from v8engines-

 

Hi Don,
Assuming you are still using the standard ECU tune then yes for sure you will be lacking the full potential of the 4.6 engine that you have. So the first place to start id with our unlocked and mapped ECU along with magnecor plug leads. I have placed below the prices for these and recommend you use NGK BP6ES spark plugs.
 
Gems 4.6 Mapped and Unlocked ECU £540.00
Magnecor plug leads £90.00
Delivery to California £50.00
 
Please let me know if you have any further questions.
 
 
 
This is an 'unlocked' ECU, meaning plug and play; I don't need to send them mine.  
I think I'll order it, though I'm going to take a pass on the Magnacore wires.  Their price isn't bad but I don't think I actually need plug wires and I'm not sold that Magnacore is worth $130 when this isn't a high performance aftermarket ignition system. 

Don
'07 LR3 HSE/HD - slightly non-stock

'96 D1 - even more non-stock


#20
JFuller

JFuller

    NCLR Guest

  • NCLR Guest
  • PipPipPipPip
  • 1,103 posts

Our P38 is stock 4.6 if you think it will help you get a feel.  Its noticeably more powerful than my D1 off the line and on the highway, it's nothing I'm going around bragging about but it is better than the 4.0.  For what it's worth.






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users