4.5 with 4.2 induction....

[M3John]

As the title suggests really guys and gals. I have herd stories of the 4.2 induction setup working on a 4.5, and working well but, am wondering about the pros and cons of it. Can anyone shed some light on this for me please?

Thanks in advance.

M3J.

[cerberamatt]

I have just had the very thing done to my red rose and should be picking it up from Automedon this evening.Fingers crossed its as good as i'm expecting,I shall let you know.I started a thread on this about 6 mths ago and got some interesting feedback,Some said it wasn't worth doing and one chap said he has got 450bhp as a result!

Edited by cerberamatt on Tuesday 11th May 07:55

[touching cloth]

Andy (apm) cerainly thinks it's the way to go and pretty sure uses 4.2 kit on Jonnys 4.7 racer making around 470 - certainly when speaking to him the other day about a conversion that is what he said should be used. Paul @ Austec also used it on Harry's 450, still the highest 4.5 out there I believe. Think it needs some extra work to get it flowing nicely though to get the big numbers, not quite just a bolt a stock one on.

You planning on increasing capacity then Johnboy, Id get them rear tyres widened first

Edited by touching cloth on Tuesday 11th May 10:17

[DuncanM]

John,

Isn't you car a 4.2 with 390bhp?

I thought you'd be pretty pleased with that .

Duncan

[M3John]

touching cloth said:

Andy (apm) cerainly thinks it's the way to go and pretty sure uses 4.2 kit on Jonnys 4.7 racer making around 470 - certainly when speaking to him the other day about a conversion that is what he said should be used. Paul @ Austec also used it on Harry's 450, still the highest 4.5 out there I believe. Think it needs some extra work to get it flowing nicely though to get the big numbers, not quite just a bolt a stock one on.

You planning on increasing capacity then Johnboy, Id get them rear tyres widened first

Edited by touching cloth on Tuesday 11th May 10:17

So is it worth me speaking to APM about this? Also your saying that it does fit but will require `extra work` ? Not after starship figures from it but am just weighing up some options at the minute but will have to move soon ish on this one.

DuncanM said:

John,

Isn't you car a 4.2 with 390bhp?

I thought you'd be pretty pleased with that .

Duncan

Yes it is but there is always the need for more.

[FUBAR]

M3John said:

Yes it is but there is always the need for more.

Judging by your FB profile pic the other day, I'd say 390horses is plenty for you

[Steve_T]

FUBAR said:

M3John said:

Yes it is but there is always the need for more.

Judging by your FB profile pic the other day, I'd say 390horses is plenty for you

Oh yes?

[Gazzab]

cerberamatt said:

I have just had the very thing done to my red rose and should be picking it up from Automedon this evening.Fingers crossed its as good as i'm expecting,I shall let you know.I started a thread on this about 6 mths ago and got some interesting feedback,Some said it wasn't worth doing and one chap said he has got 450bhp as a result!

Edited by cerberamatt on Tuesday 11th May 07:55

would love to see that on raceproved rollers...!? I am sure they would too. Did you also get a remap?

[Nickccc]

Harry had a considerable amount of other bits done to reach 450 bhp
it wasn't just swapping the induction over.

[Gazzab]

I struggle to see the cost benefit being a good one?
My red rose was 415 bhp. Had some headwork now so expect 420. If I was to get a remap and short induction we should see 440 plus. Would 4.2 set up really improve upon that? If so by much more than a couple of horses?

[cerberamatt]

Gazzab said:

cerberamatt said:

I have just had the very thing done to my red rose and should be picking it up from Automedon this evening.Fingers crossed its as good as i'm expecting,I shall let you know.I started a thread on this about 6 mths ago and got some interesting feedback,Some said it wasn't worth doing and one chap said he has got 450bhp as a result!

Edited by cerberamatt on Tuesday 11th May 07:55

would love to see that on raceproved rollers...!? I am sure they would too. Did you also get a remap?

Its not been on the rollers yet because i am running it in after a rebuild but as soon at thats done i intend getting it mapped.Just can't wait to get it back i'm like a 10 year old kid waiting for christmas.

[M3John]

Lads thanks for the info, just to shed a little more light on things.....

What i'm getting at is, if i had a 4.5 engine (complete) would it really be worth me sticking on my 4.2 induction set up or should i just stick with the standard 4.5 setup?

[M3John]

Steve_T said:

FUBAR said:

M3John said:

Yes it is but there is always the need for more.

Judging by your FB profile pic the other day, I'd say 390horses is plenty for you

Oh yes?

[FUBAR]

M3John said:

What i'm getting at is, if i had a 4.5 engine

That sounds like engine envy to me

[Chuggaboom]

M3John said:

Lads thanks for the info, just to shed a little more light on things.....

What i'm getting at is, if i had a 4.5 engine (complete) would it really be worth me sticking on my 4.2 induction set up or should i just stick with the standard 4.5 setup?

Without modifying the 4.2's you might get a bit more torque with them bolted straight on a 4.5 coz of the better design (longer) of the inlets...but its only a maybe, and obviously depends on how good the 4.5 you get is/was when it left the car it came out of.

Either way would probably need a remap and proof of the pudding only comes with going on the rollers.

But to answer the question that is possibly behind the thread, if you're being offered a 4.5 and the inlets are being offered as extra, then negotiate and have them too, then keep your options open and can tinker/trial/test etc make your mind up later which to stick with.

[Steve_T]

Gazzab said:

I struggle to see the cost benefit being a good one?
My red rose was 415 bhp. Had some headwork now so expect 420. If I was to get a remap and short induction we should see 440 plus. Would 4.2 set up really improve upon that? If so by much more than a couple of horses?

If it's not too much to ask, can we get the before and after torque curves pls?

[FarmyardPants]

Yea Gazza, have you had another RR run yet? 420.3 to beat (from a rose-free 4.5 with no engine work)

And what's all this about a 4.5 John, upgraditis already?

[FarmyardPants]

FarmyardPants said:

420.3 to beat

And that was before I fitted the clear indicator lenses. Christ knows what it's putting out now...

[touching cloth]

[BLUETHUNDER]

I say forget all that AJP malarky and find a nice LS7. Spend a bit of dosh and get proper power.....