JP Exhausts

[elbon50]

Contacted JP Exhausts of Macclesfield recently re a performance system for my car

Dave Hughes replied today saying that manifold back system would be £300 and manifold £500 plus VAT

Seems a good value compared with Mongoose/Magnex

Peter

[Lauren]

IME much better quality than Magnex/Mongoose as well (I've had both). Also get to spec exactly how you want it.

Tis the only place I'd go to.

[pk_090]

What kind of style and exhaust size did they quote peter? Im after a jap can single big bore style unsilencer. PW said not to really go above 2.5" dia pipe so was just curious what they quoted you on.
Alex

[elbon50]

What kind of style and exhaust size did they quote peter? Im after a jap can single big bore style unsilencer. PW said not to really go above 2.5" dia pipe so was just curious what they quoted you on.
Alex

Will get back to you on that when I've had more discussions with em Alex

Peter

[Neil_turbo]

Everyone knows my thoughts on JP

[Icsunonove]

And mine

[LimeyMk1]

What kind of style and exhaust size did they quote peter? Im after a jap can single big bore style unsilencer. PW said not to really go above 2.5" dia pipe so was just curious what they quoted you on.
Alex

The final bore of my V6 exhaust is 2.5 inch so on a 4AGE I reckon 2.5 inch is going to be too big.

Allo Tom!

[elbon50]

What kind of style and exhaust size did they quote peter? Im after a jap can single big bore style unsilencer. PW said not to really go above 2.5" dia pipe so was just curious what they quoted you on.
Alex

The final bore of my V6 exhaust is 2.5 inch so on a 4AGE I reckon 2.5 inch is going to be too big.

Allo Tom!

Yes, my understanding of N/A tuning is that pipework sizes must be correctly matched to total swept volume, so that the outflowing gas column helps to draw the inflowing column through

Its a matter of gas column speed

It's different with forced induction i think, for obvious reasons

Peter

[pk_090]

With forced induction it is less critical. You want the gasses to exit as quick as possible as there is no need for the gasses once they have exited the turbo outlet. Manifold tube length should be considered so to get optimal results.
N/A Should be big enough, to not cause a restriction but no too big as to slow the flow down. Back pressure is important but not as important as on a 2 stroke where it is essential! Anybody know the standard exhaust dia?
Alex

[SuperRedMR2]

The overall length of all pipes must be the same.

When I started to draw my own manifold the pipe on the 4AGE I think the pipe dia was 36 i/d with a 3mm wall, which would make it to the nearest pipe schedule 42.4 diameter outside which is about 1 1/2" I think

[LimeyMk1]

The overall length of all pipes must be the same.

Depends how you want your torque to be delivered, there's a good argument for unequal length primary pipes to reduce the 'peakiness' of the torque curve. While you may not get the highest peak the spread will be more even and you'll get a more drivable car.

[Lauren]

With regard to manifolds there is also the option of whether to go:

4-2-1 (as on most cars). Better for torque

4-1. Better for peak power.

Interestingly my car currently has a 4-1 on it.

[AdamP]

With regard to manifolds there is also the option of whether to go:

4-2-1 (as on most cars). Better for torque

4-1. Better for peak power.

Interestingly my car currently has a 4-1 on it.

4-1 is better for peak torque. 4-2-1 will spread the torque over a larger range.

If they aren't 'designing' it (ie they are just welding pipes together) then it doesn't matter a jot. You can't do it by guesswork really.

[mihogal12]

Contacted JP Exhausts of Macclesfield recently re a performance system for my car

Dave Hughes replied today saying that manifold back system would be £300 and manifold £500 plus VAT

Seems a good value compared with Mongoose/Magnex

Peter

any pics on this?

[elbon50]

Contacted JP Exhausts of Macclesfield recently re a performance system for my car

Dave Hughes replied today saying that manifold back system would be £300 and manifold £500 plus VAT

Seems a good value compared with Mongoose/Magnex

Peter

any pics on this?

No pics yet

Intend to get back to them ASAP re more details

Peter

[elbon50]

Have emailed them again this morning asking for more info & pics

Thanks for reminding me Mihogal

Peter

[IanParkhouse]

Spent a long time talking to John at JP exhaust very helpful bloke. Once the 2zz is back on the road in the spring I'll be dynoing it then up to JP for a full system including manifold.

[Neil_turbo]

Guess you don't mean mapping then to JP?

I had to have a run in map put on mine, then take it to JP for exhaust whilst I was running in, then back for a full map, meant a lot of travelling (which actually helped run in) but had to get it in the right order!

[elbon50]

They're asking me if I will send my exhaust to them

Presumably so they can use the measurements to make a new one for me

I thought they had made systems for Mk1 with 4A-GE before

Peter

[Lauren]

You could do that, but tbh the normal way to do it, is simply to take your car down so they can make a bespoke system for you.

You drop it off in the morning and collect it early afternoon.