Where can I find another 40 bhp ?
Discussion
I know the fashion at the moment if looking for a little more power is to fit a blower, however I would prefer not to go down that route. My 500 is fairly lightly modified with a 224 cam, carbon fibre trumpets, smooth bore inlet pipe and Mr Adams had a fiddle with it. Allegedly, a couple of years ago it was producing about 300bhp. Other than going forced induction what would all you modifiers recommend if I was looking for say another 30-40 bhp but without making it even less friendly to drive in traffic ?
Wilder cam
Fully mapped ignition and fueling
JE type throttle bodies (fit under Griffith bonnet)
Make sure inlet tract is matched to trumpets through to heads
You may then have to consider bigger injectors, although all this will largely depend on the cam in the first place. I'd start with V8D and talk to them about a reliable 350 through induction work.
Not qualified enough to discuss whether solid lifters/roller rockers etc are necessary for 350, my understanding is that they are not, but depends how you'll be using the engine.
Joolz V8S is claimed to put out over 350, so worth a conversation with him in terms of mods.
If I were after those kinda numbers I would certainly be going down the multiple throttle route, especially looking at JE's set up at his workshop the other month . . . I already have a fully mapped wasted spark set up as this was the best first step down this route rather than being tied to one tuner for all the tuning work after any mod I chose to make.
Fully mapped ignition and fueling
JE type throttle bodies (fit under Griffith bonnet)
Make sure inlet tract is matched to trumpets through to heads
You may then have to consider bigger injectors, although all this will largely depend on the cam in the first place. I'd start with V8D and talk to them about a reliable 350 through induction work.
Not qualified enough to discuss whether solid lifters/roller rockers etc are necessary for 350, my understanding is that they are not, but depends how you'll be using the engine.
Joolz V8S is claimed to put out over 350, so worth a conversation with him in terms of mods.
If I were after those kinda numbers I would certainly be going down the multiple throttle route, especially looking at JE's set up at his workshop the other month . . . I already have a fully mapped wasted spark set up as this was the best first step down this route rather than being tied to one tuner for all the tuning work after any mod I chose to make.
Edited by Johno on Wednesday 24th September 16:07
Bluebottle said:
If not FI 
...then I would look at coil packs and mapped ignition to get the best out of the full rev range. I've heard that this can release 30 plus bhp
...then I would look at coil packs and mapped ignition to get the best out of the full rev range. I've heard that this can release 30 plus bhp
If you want drive-ability and power then a fully mapped system is the key.
Mine is smoother now with 330bhp than it ever was with 280bhp.
A KMS mapped ignition system from Joo at Trackcar plus a 72mm throttle body and a large radius bend got me 36hp on a 450 Chim with a 218 cam, up to 305. The KMS is adaptive, so will remap itself for any future mods provided they don't involve fundamental things like cam or capacity. Very nice and drivable (=well behaved in traffic queues). The old rule of thumb of £100 per hp is about right.
Ian.
Ian.
To could gain 25 to 30bhp by fitting Clive F's tuned manifolds. Figures backed up by before and after graphs on Joos RR at Trackcar.
V8enhancements (Click on exhaust)
V8enhancements (Click on exhaust)
Despite my initial reluctance to go FI it does seem to be the most effective route to gaining some power but also keeping a drivable car. I may be missing the point here but a wilder cam gains a bit, throttle bodes gain a bit, manifolds gain a bit, proper Ecu gains a bit more and allows taming of all those bits. Go back to a milder cam and stick a fan in the system and you seem to gain quite a lot all in one go and keep the drivability at the same time.
steve-V8s said:
Despite my initial reluctance to go FI it does seem to be the most effective route to gaining some power but also keeping a drivable car. I may be missing the point here but a wilder cam gains a bit, throttle bodes gain a bit, manifolds gain a bit, proper Ecu gains a bit more and allows taming of all those bits. Go back to a milder cam and stick a fan in the system and you seem to gain quite a lot all in one go and keep the drivability at the same time.
Yep, that's about the size of it 
I have seen people spend huge sums of money on mods that at the end of the day may have given them 330-350 max BHP, the andvantage is its incremental so you don't blow £5k plus in one hit but for similar money you get 400-450 bhp with FI instantly and without the need for a fancy ecu (granted it helps but isn't necessary) just a chip upgrade for you 14CUX (doesn't need to be Tornado chip either as there are others out there doing custom chips) after all once its installed you ain't gonna need further mapping for other mods as there isn't any more needed.
What i didnt like about going to forced induction,when i considered it,is the fact that on a std engine you have to run low boost,or sacrifice reliability.To do forced induction properly you really should rebuild the engine to a much stronger spec to enable use of a decent quantity of boost reliably,then the cost increases significantly.To run a blower on such limited boost to ensure reliability seems to be a half measure to me,just cant see the point,really.
Love it or lothe it,the LS engine is going to give you the most BHP for your money,though if you only want another 40bhp,you would get that without forced induction or engine transplants,and still be very driveable,and it would be the cheapest of the three.
Love it or lothe it,the LS engine is going to give you the most BHP for your money,though if you only want another 40bhp,you would get that without forced induction or engine transplants,and still be very driveable,and it would be the cheapest of the three.
Edited by The AJP Griff on Thursday 2nd October 19:40
trackcar said:
does a low pressure blower really give you 400-450bhp on an otherwise std engine? I'd like to see that. I reckon you'd need 15psi on a supercharger to get that. theoretically 11psi should get you to the upper end of your numbers, but in reality you'd be looking at 15psi surely?
It really can, my car produced 438lb/ft torque on its first run (un-mapped)unfortunately my compression ratio was to high and MA had to back the ignition off to 23 Deg. to stop pinking even at that it produced 390lb/ft. The Rotrex is geared to produce 6lb peak boost at about 5.5k rpmI wasn't happy at losing over 50hp, as my comp ratio was way to high and having an old 3.9 case so small journals and no cross bolting i decided to have JE build me a short engine (well actually i was told i'd snap my crank if i didn't) that will allow me to wind the ignition back up to 26/28 Deg. Internally balanced crank, forged bits and lowered compression, increased capacity, I'm expecting it to make 440-450lb/ft and pull all the way to the rev limiter as before (without pinking).
I've seen a couple of the chimp boys making 400-425 lb/ft torque also from their 450 engines not pinking so it does seem to be repeatable power.
Edited by Bluebottle on Thursday 2nd October 21:33
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