I just bought an 01’ Exige RHD that was imported here to the US a year or two ago. The previous owner had just had some major top end work done to the car along with a tuning on a rolling road.
Here are my questions,
-Is it safe to spin the engine to 8000-8300 rpm with the stock bottom end? It has 1444 cams/solid lifters and was fitted with larger valves and an Emerald ECU. It has a stage II exhaust and aftermarket airbox (not sure yet about the throttle bodies)
-This combo only yielded 150bhp at the wheels on the rolling road, does this sound right?
Sounds like a King-K special! (Search the archives!)
K-series sages reckon that the bottom end should really be properly balanced for a lot of use at those revs. Occaisonal excursions up there shouldn’t be a major drama though.
150bhp does sound very low - to the point of something being wrong… (+25/30 bhp for transmission losses = 175, 180?)
If it has an Emerald ECU, it may well have been mapped for 98RON fuel. If using standard (91?) US pump gas it is probably really struggling.
Other than that, I guess you’re into looking for blocked filters, poor fuel pressure, blocked Cat / exhaust leaks, dodgy cam timing etc…
Welcome along though. You’ve still got a great car and ultra rare in the US as RHD.
If it was a KingK engine it would be safe to rev that high constantly, but then it would have made a bit more power
I would guess that combo at the wheels should be putting out 190-200 BHP (or more if American horses)
Maybe the cams are times wrong? or like mentioned: air filter, fuel pressure, wrong map, etc.
You’ll have to read a lot here this site and get intimate with that engine.
Then you’ll see what’s wrong.
Can I also suggest at least checking (but probably replacing) the spark plugs. Mine was down on power recently and the one plug was found to be the main problem. Other suggestions pretty much as others have already posted, check the cam timing, the fuel pressure, clean the fuel regulator, flush the injectors, clean/replace the air filter.
None of this should be costing you silly money and it may just make the world of difference.
Thank’s for the responses,
The car was tuned on race fuel not pump gas (100 octane unleaded).
The tuning was done by a reputable Porsche tuner Deman Motorsport (not to many Rover guy’s this side of the pond)
When they started tuning, the base run shown a A/F ratio that varied greatly and was showing a lean condition. They were able to retune it to a stable 13:1 A/F ratio from 50% throttle and higher through the rev range so I don’t think fuel is the problem. I do agree that the cams may not be timed properly and that will be the first thing I check.
My main concern is that the bottom end being untouched can handle the revs. This is a dedicated track car (not road legal here in the states) and will spend a fair bit of time in the upper rev range.
I am going to have it dyno’d (American term for rolling road) at my buddies shop to get a baseline before making any changes since results differ between dyno’s.
As far as a RHD Exige being rare in the US, there are only like 13 Exige’s total and as far as I know this is the only RHD.
I’ll post when I find where my lost ponies have been hiding.
Are you at altitude or at sea level, if at altitude you can add 17% to the figure to get a more representative number.
I have had the same problems with my engine, pretty much the same top end spec, your torque figures should be very good with the 1444’s, meaning that it might be futile to continuously rev it to 8300rpm, I found some of my best times were shifting at 8000rpm dropping the engine back onto max torque, as opposed to running up to 8500rpm in every gear.
As far as 8000rpm on a standard exige bottem end - my guess is OK
8300rpm on the track, touch and go, if you want to keep it above 8K on the track at the very very least install steel rods.
I installed all the trick bits in mine with the intention of having an engine capable of sustained 8.5k use and ended up with a torque curve at the moment which means I could have left it all with the 7800rpm limit so look at the curves before moving rev limit to far up.
Jason,
Your point is well taken. I’m not sure what the exact torque figure is, the PO showed me one of the rolling road graphs while going through all of the cars paper work and I did note that it was a nice and flat curve. Although I guess that map was from before the Emerald ECU was properly tuned. I’m in the process of getting the latest maps from the tuner that did the work.
I don’t necessarily need a 200+ HP K to make me happy, espesially with the wieght of the car (right now with 150 at the wheels it has the same power to wieght ratio as my Esprit which has 285 at the wheel and that thing halls) I am just tring to determine if the work that has been done to engine has been performed properly. Since the cams and head work have been completed the car has basically only had a few miles of rolling road time and limited road miles (no track time). I don’t want to take this thing out to my first track event this year and have the motor go BANG!!
I also would just like to wrap my head around what I have just purchased, I’m not the type that just puts gas in the tank and drives, bringing it down to the local shop when it brakes. I don’t trust anyone to work on my equiptment but myself. So keep the info coming
One more quick question; Would the standard engine in the Exige be considered the VHPD K series?
Mike
I believe I know a little about the history of this engine, a lot of parts were sourced from the UK (not from me) but the head work and assembly work was done in the USA. Late in the day when the engine builders needed some extra information/ tappet shims etc. they contacted me and I gave them some advice on cam timing, and general engine/mapping information.
The owner had assumed since I was advising FOC that I had supplied the parts/specified the parts and I received a robust if not rude email from him giving me a bollocking because the engine didnt make the expected output. It tokk an email or two from me to explain that I had done nothing except provide free remedial advice.
There may be issues with the headwork and cam timing, there may also be some issues with the mapping, since I havent seen the engine or the head I can’t be sure, on paper the spec. should be capable of producing over 220BHP and 150-160lb/ft…
Dave,
That sound like the way it went down. From what the previous owner told me, the shop that was doing the work was struggling to bring it to completion and in the end the car was brought to another tuner to be completed (be it only as far as fuel and spark mapping), any mistakes or oversights in cam timing or porting surley still exist.
I don’t really fancy tearing the head off the car and going over the job with spring so close and considering that I haven’t even had the chance to drive the car yet. I guess it depends on how easy it is to pull the head. I haven’t had the chance to go over the manual, is it possible to remove the head with the engine insitu? Is there a consern with the long head bolts and other components that they hold together?
Removal of the head is exacting but straightforward, there are a few little caveats such as the correct crank position prior to removal and the fitment of liner clamps once the head is off, but overall it’s not a problem.
I am aware of course that you are 000’s of miles away and the normal, ‘I’ll drop round and give you a hand’ rules dont apply, so only attempt the removal if you are happy that you can see it through.
Mike, the first thing you should do is check the timeing, and for this you don’t really need to remove the head, just the cam cover ad the plastic cambelt cover on the side.
Then with a dial depth gauge on the lifter you should be able to check the timing.
To do an effective check on the cam timing requires a bit more expertise than Uldis explains.
I have a comprehensive document explaining how the cam timing is tested and set which I can send to you, you will need at least two dial gauges, preferably one anlaogue and one digital and some carefully crafted bracketry to attach them.
all this information was given to the engine builder(s) while your engine was being put together, whether it was heeded is hard to say.
If you would like a copy of the document, let me know and will mail it.
Well I’ve got two dial indicators in the tool box and one magnetic mount, I guess fabing up a second mount shouldn’t be too hard. Do you have to install a liner clamp if you don’t disturb the crank position after removing the head?
This motor architecture is sounding alot like the 2.2L in my Esprit.
It would be great if you could email me that proceedure Dave.
A magnetic mount isn’t too useful on an aluminium engine…
Documents on their way.
You don’t need liner clamps if you don’t turn the crank with the head off, however the last two persons who did this (one in the USA) turned the crank in error and had to remove their rods, pisons and liners and re-seat them. TBH it’s simple to make liner clamps out of old bolts and it gives a good safety margin.
Stop press…
Your ISP just bounced my mail with documents attached…