I am contemplating purchasing these...

 

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-25-bolt-stainless-steel-downpipes-p-2958.html

 

Can I ask for people's opinions please?

 

Not sure if they are a bit limited with regards to power enhancements in the future.

As things stand, I intend to stick with stock turbos and just enhance their performance further down the line.

ie raising boost and improving induction etc.

Just do not want to end up with them being a limiting factor that's all.

 

Would appreciate it if you would share your thoughts guys, even if it means an alternative downpipe design/manufacture.

 

Thanks in advance...

Are the IC's pipework dimensioned in the same way as the downpipes Andrew? IE as the outside diameter.

 

Yes, at least normally. I've posted pics of the SZ 2.5" supersplits here:

 

https://www.300zx.co.uk/forums/showthread.php?187498-Help-Part-measurements-anyone&p=1952767&viewfull=1#post1952767

Hi Dougal200, when you do come to put these up for sale, please let me know.

 

Sure thing, ideally I would like to sell them complete with the test pipes though. I'll send you a message nearer the time, I should be able to bring the along to protuner

ideally I would like to sell them complete with the test pipes though.

 

I can understand that, makes sense really.

If I was totally honest with you, the more I look at the Z1 2.5" down pipes complete with wide band access, the more tempted I am.

If it wasn't for the price, I would probably opt for the full split that Andrew has.

 

So in the interest of not messing you around mate, I'll withdraw my interest, apologies.

Just trying to compile a final list. (To be added to as I go.)

So far I have decided upon the following...

 

1. Z1 2.5" "4 Bolt" Stainless Steel Downpipes.

2. Modify my existing throttle bodies. (Budget over preference, may reconsider.)

3. 2.5" intake pipework. (Manufacturer undecided as yet, not sure which ones will fit recirc valves without modification, if any.)

4. Larger SMIC's, considering Z1. (need to understand how they will fit.)

5. Retain my existing exhaust system for now.

Wasting money on the Z1 downpipes IMO. Megan ones from CZP are almost $100 cheaper, just had them fitted to mine. Jimmer advised me not to bother with Z1's in the past and get Japspeed, and thinks the Megan ones he's just fitted are a good alternative to Japspeed's

 

https://conceptzperformance.com/megan-racing-v2-4-bolt-downpipes-nissan-300zx-90-96-twin-turbo-tt-z32-mr-ssdp-n300-v2-dp_p_28564.php

Wasting money on the Z1 downpipes IMO. Megan ones from CZP are almost $100 cheaper, just had them fitted to mine. Jimmer advised me not to bother with Z1's in the past and get Japspeed, and thinks the Megan ones he's just fitted are a good alternative to Japspeed's

 

https://conceptzperformance.com/megan-racing-v2-4-bolt-downpipes-nissan-300zx-90-96-twin-turbo-tt-z32-mr-ssdp-n300-v2-dp_p_28564.php

 

Valid point Chris.

Do they have the wideband fitting at the exhaust flange?

What was Jimmers main criticism?

Yep mine did. I don't want to put words in his mouth but I think he thought Japspeed ones were just as good basically. If it makes you feel better even Funkysi said Megan products are normally alright when he looked at mine :biggrin:

 

Struggling to decide on which intake pipework and inter coolers to go for.

I think the Z1 SMIC's are out as they appear to involve too much installation work.

Loss of carbon canister, modify the chassis, indicators and mess with the recirculation valve set up.

(I think they are just free as opposed to being bolted down!)

As for the pipework, I can't seem to determine how any of them are fixed in situ. Are they just free standing?

eg.

http://specialtyz.com/shop/300zx/intercooler/ash-2-5-smic-piping.html

https://www.z1motorsports.com/z1-products/z1-motorsports/z1-25-piping-and-intercooler-combo-p-6555.html

http://specialtyz.com/shop/300zx/intercooler/ash-2-5-smic-piping.html

Dave you changed out your radiator cross member, compared to that installing 2.5" pipework and ICs is straighforward if fiddly!

 

Any of the 2.5" piping kits are a tight fit (particularily if you have an aftermarket larger radiator). This post gives some tips:

 

http://www.twinturbo.net/nissan/300zx/forums/technical/view/1115348/VTF-25-Intercooler-Piping-Install-Tips-Trick-amp-Hints.html

 

AshSpec piping has mounting tabs to stock fixing locations. I'm not sure about Z1. It is so tight that there is little room for

anything to move about.

 

Larger intercoolers are also a tight fit. You can lose the CC or replace with a smaller one ( Skyline GTST) moved to a new

location. The modifications to the recircs are straightforward:

 

http://twinturbo.net/nissan/300zx/forums/general/view/2483641/Pics.html

 

with Ashspec planar inlet piping:

 

http://www.twinturbo.net/nissan/300zx/forums/general/view/2491225/Recirc-plumbing-with-ashspec-planar-mounts.html

 

Frame rails typically need cutting back to make clearance for IC pipework and/or couplings. Modifications to lights are required to clear

front of ICs, but the process is well documented (in the Z1 installation instructions for example).

Thanks Andrew for the very informative links.

 

I agree wholeheartedly about the difference between the cross member repair and the intercoolers with associated pipework etc'.

This upgrade will be a walk in the park in comparison.

 

I guess I am just a little reluctant to alter things such as indicators, ducts and chassis in such a physical way.

I guess if it is done in such a way that it does not look too much of a crude work around I will be able to live with it.

 

As you say, it's good to know that there are fixing points for the AshSpec piping. (I would prefer everything to be securely bolted up.)

With regards to the recirc's, I guess I might have to live with them being unsecured, maybe use a more rigid type piping as suggested in one of the write ups.

 

I know this is not worth considering, but I would like to ask..

Would it be much of a compromise if I chose the smaller direct fit Z1 intercoolers and adapted the 2.5" pipework to fit?

 

Also, what is the difference with regards to the planar pipework?