4.3 to 4.6 upgrade ?
Discussion
griffdude said:
I did something similar about 18 months ago.Very effective.Also didn't get ripped off on the insurance.
I'd already done brakes/suspension.
Hint....Get the gearbox reconned whilst the engine is out....Diff ok tho(TOUCH WOOD)
>> Edited by griffdude on Sunday 13th November 18:04
What sort of power does it give?
I must admit its a conversion I would love to do.
We could start a whole new genre, 4.6 precats...........
A
Excellent. I note that JE do a 4.6 long engine complete. I already have upgraded brakes at the front and the shocks have been replaced with Avo's, would that suffice and is there any modifcations that were necessary (noting diff). Presuambly the 4.6 block needed no chassis mods. Could I ask where you got the 4.6 from ?
v8 racing said:
A 4.6 with a h404 st3 heads and the uprated induction system will around 280 bhp in a tiv basically the same as a standard 500 but a little bit down on torque, either way a good increase will be had!
That sounds a little pessimistic to me.. not that I have much experience to base my statement on.. apart from I saw a nice but standard 4.5 chimp make 276bhp on Surry's rollers a couple of months back. A 4.6 with stg3 heads, cam, and induction kit would make a bit more than that, surely it would be nearer 290-300???
Would you stick with the cux ECU or swap it for something else? what about ignition seeing as the 4.6 block has crank sensor casting (I think?) you could quite easily run wasted spark to get rid of the sometimes dubious dizzy. Which is also not required to drive the oil pump if you have the serp/gems timing covers??
Anyone put me straight if I'm talking RRRs.. I'd like to learn more about this so lets not let the thread die yet
I haven't had it on the rollers since it has been run in. Initially it was +35hp +40torque, its now got another 10k miles so could be a couple more?I had expected greater gains to be honest. However at a trackday in the summer it out dragged std 5ltr cars down the main straight, out braked most things & had a riot thru the twisty stuff. Although my car doesn't produce a stratospheric output, it's still bloody quick & yet remains good mannered & tractable.
griffsmith said:
A 4.6 with a h404 st3 heads and the uprated induction system will around 280 bhp in a tiv basically the same as a standard 500 but a little bit down on torque, either way a good increase will be had!
That sounds a little pessimistic to me..
I would say that 280 bhp is a little optimistic based on my own experience with a similar engine with a 218 cam, but I suspect the man who built the engine knows a little bit more about these things than I do.
Unless your 4.3 is knackered, you could always do what I did: BV heads, raised CR, 72mm throttle disc (standard plenum / manifold) and Motec. Gives 300 on my usual RR and 294 at SRR at few months back.
Of course the downside is only 2 bolt main caps, and still using the dizzy driven oil pump (although you can use the intermediate cover to get the crank drive but it means removing the crank to machine the keyway).
7.
Of course the downside is only 2 bolt main caps, and still using the dizzy driven oil pump (although you can use the intermediate cover to get the crank drive but it means removing the crank to machine the keyway).
7.
after building these engines for twenty years and putting together well over 1000 engines in various specs a 4.6 as described fitted in a griff makes the figures i mentioned, personaly a rolling road is a peice of equipment to aid setting an engine up to run correctly it is not there to show how much bhp your car is making, it is almost impossible to get a 100% accurate reading from a rolling road unless it is in a wind tunnel with a controlled air temp, times i see rolling road tuners do a power run with the bonnet of????? how can this be accurate when the engine will be running much cooler and more air to the air filter if situated under the bonnet, put the bonnet back on and you are likely to get the engine to pink!!! sorry for this little strop but it is getting out of hand with people saying mine makes this and yours only makes that!!!!! from an engine builders point of view and an HONEST one at that i cant b******* my figures its just not me, however when a guy or gal now come to me saying that they have a 4.6 that makes a lot more power than i know it actually does just come some rolling road says so and wants an upgrade what can i offer the figures i will say will make less than he supposedly has!!!!! not perticually good value for money hey!!
v8 racing said:
Pete the h404 is worth around 20 bhp over the 218, the 218 does idle nicer admitedly, if you grind the weights in the dizzy so the advance doesnt come in quite as early a 404 does drive very nicely with no bad manners at all, ps did you eventually get yours running properly?
Interesting Rob, so my 3D ignition should allow me to get the best out of the H404, should I get it fitted . Harry
v8 racing said:
i will book you in next week!!
still considering my options, do spend yet another £1K on the V8S or get the Cerb I've been promising myself for the last year or so . Seriously though currently I'm putting around the 230 out at the wheels (275ish fly) so I would be very surprised if the H404 made another 20hp over the 218 I have, not that I wouldn't mind, the old 4ltr will be knockling on the door of 300 then
. Do you have any curves that show what happens to the Torque as I'm a little concerned that I might drop some of that
. Harry
Rob just noticed your post about RR figures before . Just to back them up a bit the engine left you with 255 at the fly with standard exhaust, generic MA map (ie unmapped ) and no 3D ignition, so am quiet confident it makes the numbers as it has progressed nicely since then to this point.
Harry
. Just to back them up a bit the engine left you with 255 at the fly with standard exhaust, generic MA map (ie unmapped ) and no 3D ignition, so am quiet confident it makes the numbers as it has progressed nicely since then to this point. Harry
.Must admit i'm so impressed by this cam.It was reading guillotines' recomendation that made me choose it,and i haven't regretted it one bit-fabulous camHi Harry i have never back to backed the 218 against a 404 on a 4 litre only on a 4.6 which i have done 3 times only swapping the cam and all 3 times it made a minimum of 20 bhp, i would have thought on a 4 litre you should still see a good 15 bhp, i will dig the dyno graphs out and mail them to you
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