zedhead260
Well-Known Forum User
Nothing in terms of peak HP, it's what happens between zero & peak that counts.
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Got the Z rolling road tuned today
- Thread starter richiep
- Start date
Nothing in terms of peak HP, it's what happens between zero & peak that counts.
richiep
Club Member
Okay - you've convinced me on the cam! TBH, I wasn't planning to make any rash changes anytime soon in that department - getting to know the car and how to get the most out of the throttle response as it is will be the main goal over the coming weeks.
Rob - the 176 at the wheels was calculated out from the engine reading. I will try and post the graphs this weekend to give all the info.
Next mechanical step, probably soon after Japfest (or maybe immediately after Tatton Park at the end of May) will be to get going on the new exhaust setup. I also need to swap my R200 in. I will probably take it to Ric's again after that to see how the power and torque curves are affected. Hopefully, as mentioned above, the lower rev response will be improved and the 2250rpm dip can be smoothed somewhat.
Cosmetically, the next step is a deeper front spoiler in typical aftermarket JDM style - like this:
I have in fact got one, which I got off eBay from a source in Thailand (often has JDM fibreglass repro parts for sale), but it was an utter piece of sh*te - looked good until you offered it up to the car and discovered it was over 2 inches too short width wise! Totally useless and good money thrown away. I'll probably be ordering a replacement from ZCCJDM in the US imminently.
P.S. I love those wheels too. In an ideal world (with all other Z mods fitted and most importantly fully paid for!!!) I'd love either a set of Watanabes (16x8 preferably) or these above - Hayashi Racing Street wheels in 15x8. Yummy! Mine would be scrubbed up nicer than the ones on the photos though!
Rob - the 176 at the wheels was calculated out from the engine reading. I will try and post the graphs this weekend to give all the info.
Next mechanical step, probably soon after Japfest (or maybe immediately after Tatton Park at the end of May) will be to get going on the new exhaust setup. I also need to swap my R200 in. I will probably take it to Ric's again after that to see how the power and torque curves are affected. Hopefully, as mentioned above, the lower rev response will be improved and the 2250rpm dip can be smoothed somewhat.
Cosmetically, the next step is a deeper front spoiler in typical aftermarket JDM style - like this:
I have in fact got one, which I got off eBay from a source in Thailand (often has JDM fibreglass repro parts for sale), but it was an utter piece of sh*te - looked good until you offered it up to the car and discovered it was over 2 inches too short width wise! Totally useless and good money thrown away. I'll probably be ordering a replacement from ZCCJDM in the US imminently.
P.S. I love those wheels too. In an ideal world (with all other Z mods fitted and most importantly fully paid for!!!) I'd love either a set of Watanabes (16x8 preferably) or these above - Hayashi Racing Street wheels in 15x8. Yummy! Mine would be scrubbed up nicer than the ones on the photos though!
datsun dave
Club Member
Nice picture Richard you want some clear headlamp covers next !!!!!!
jay28
Well-Known Forum User
Speaking of manifold and exhausts, these are the best L6 manifold I have came across, they are a work of art.
http://www.kameariengineworks.co.jp/catalogue-P35.pdf
http://www.kameariengineworks.co.jp/catalogue-P35.pdf
richiep
Club Member
Okay - just got back from my first proper play on Cheshire's A roads...
Crikey. It wasn't like that before.
It clearly lacks a bit of low end response due to the cam - at low speeds, the throttle needs to be feathered a bit. However, over 2,500rpm, foot to the floor and everything gets a bit evil! The sound is great!
Feeling rather pleased at the moment!
Crikey. It wasn't like that before.
It clearly lacks a bit of low end response due to the cam - at low speeds, the throttle needs to be feathered a bit. However, over 2,500rpm, foot to the floor and everything gets a bit evil! The sound is great!
Feeling rather pleased at the moment!
Mr Ex
Inactive
Okay - just got back from my first proper play on Cheshire's A roads...
Before they get lowered to 50MPH.
richiep
Club Member
Before they get lowered to 50MPH.
Well I was being "liberal" with my interpretation of the existing NSL, so Neue Arbeit can stick their car-hating, ideologically motivated reduction to 50 up Gordo's non-driving ass!
Hopefully their plans will not come to fruition seeing as electoral extermination awaits them and I'm no longer sure Labour can defer an election for another 14 months given the developing economic calamity. The Tories have already stated that they would not pursue this policy.
Richie
The airbox will improve performance ...in some areas around 10 bhp, however this is generally more of a "filling in" type of effect in the usual torque holes that appear when running tubular manifolds.
Open trumpets will deliver 3 or 4 hp more at the top end but the AFR is all over the place due to reflected pulse issue of the interior wings plus do you really want dusty 60 degree air entering your nice clean cylinders and screwing the bores up.
I have found a set of dyno graphs that Dave Walker
and I did ..."with and "without" airbox, demonstrating the effect of close proximity bodywork and cooler air....I will post them up in a day or two
Sean
Big spec cams are a good thing (big lift, big duration etc) there is nothing like the sound of a straight 6 on full chat.
I am quiet happy with my new cam (500 thou lift and 300+ duration) still I'll wait until I get some power readings before reaching for the tissue box as it is coupled with a large bore header so the gas speed might be a bit slow....still should make max power at around 7K plus...ideal for crossing the line in 3rd.
I have a Schnieder stage 4 cam that is new in the box to try one day ....490 lift and about 295 duration.
The airbox will improve performance ...in some areas around 10 bhp, however this is generally more of a "filling in" type of effect in the usual torque holes that appear when running tubular manifolds.
Open trumpets will deliver 3 or 4 hp more at the top end but the AFR is all over the place due to reflected pulse issue of the interior wings plus do you really want dusty 60 degree air entering your nice clean cylinders and screwing the bores up.
I have found a set of dyno graphs that Dave Walker
and I did ..."with and "without" airbox, demonstrating the effect of close proximity bodywork and cooler air....I will post them up in a day or twoSean
Big spec cams are a good thing (big lift, big duration etc) there is nothing like the sound of a straight 6 on full chat.
I am quiet happy with my new cam (500 thou lift and 300+ duration) still I'll wait until I get some power readings before reaching for the tissue box as it is coupled with a large bore header so the gas speed might be a bit slow....still should make max power at around 7K plus...ideal for crossing the line in 3rd.
I have a Schnieder stage 4 cam that is new in the box to try one day ....490 lift and about 295 duration.
jay28
Well-Known Forum User
Thats the exact cam I have, You can reallt notice the difference in power at about 4200 rpm and the sound is awsome
It's still pulling hard at 6500 when I change gear, I'm too nervous to rev anymore incase something goes pop
It's still pulling hard at 6500 when I change gear, I'm too nervous to rev anymore incase something goes pop
you have to see how far it will go
you should be safe aslong as it is still pulling .
Richie
You mention that your cam is a little rough and lumpy down the bottom end, I would tend to look at areas such as spark timing/plug gap/plug temp, carb jetting (accelerator pumps etc) choke sizes and the exhaust header design as well as the cam as the stage 3 isnt that aggressive....when you were at the rolling road did they time the cam in (presuming that you have an adjustable sprocket) if not then this may help.
Looking forward to those graphs
You mention that your cam is a little rough and lumpy down the bottom end, I would tend to look at areas such as spark timing/plug gap/plug temp, carb jetting (accelerator pumps etc) choke sizes and the exhaust header design as well as the cam as the stage 3 isnt that aggressive....when you were at the rolling road did they time the cam in (presuming that you have an adjustable sprocket) if not then this may help.
Looking forward to those graphs
Don't do secrets mate, life is way tooooo short, if you look in my gallery there are a couple of old ones (around 250HP and a couple of generations of map/cams/headers ago), there is also a 3D model of the ignition map I think
if not I can post one up or send you the text file.
richiep
Club Member
Hi Steve,
The cam sprocket is not an adjustable one. The session focused on carburettor setup and timing (I'm not sure if plug gaps were addressed, seeing as I was at work during the session). The positive change has been marked in terms of responsiveness and power. Ric was confident that the carb setup was now optimal for what I have on the car. The only thing I think needs revisiting is the timing, as although Ric added a couple of degrees advance based on the dyno readings, it is running on when warm quite a bit now, making me inclined to back it off again (stopping the engine isn't exactly "elegant" at the moment!)
I suspect, based on the many discussions here, that the 2250rpm torque hole may be smoothed somewhat when I address the manifold/exhaust situation in a few weeks. Ditto when I install the airbox (I'll let you know when I'm ready to go for that Steve). The MSA 6-1 header's weaknesses have been discussed before compared to the NISMO item - going with that manifold and the matching off-the-shelf exhaust was a bit of a compromise, partially for cost, but also so I could get back on the road last summer. This summer, I will implement what I really want in that department.
I will try and post the graph in the next couple of days - I don't have a scanner but have a camera with very good macro capability, so I'll take a close-up snap.
Frustratingly, I won't be able to drive it again until next weekend though - its currently sitting on a manky set of original steel wheels (with complementary flat tyre) courtesy of Datsun Dave while the real ones are being refinished.
The cam sprocket is not an adjustable one. The session focused on carburettor setup and timing (I'm not sure if plug gaps were addressed, seeing as I was at work during the session). The positive change has been marked in terms of responsiveness and power. Ric was confident that the carb setup was now optimal for what I have on the car. The only thing I think needs revisiting is the timing, as although Ric added a couple of degrees advance based on the dyno readings, it is running on when warm quite a bit now, making me inclined to back it off again (stopping the engine isn't exactly "elegant" at the moment!)
I suspect, based on the many discussions here, that the 2250rpm torque hole may be smoothed somewhat when I address the manifold/exhaust situation in a few weeks. Ditto when I install the airbox (I'll let you know when I'm ready to go for that Steve). The MSA 6-1 header's weaknesses have been discussed before compared to the NISMO item - going with that manifold and the matching off-the-shelf exhaust was a bit of a compromise, partially for cost, but also so I could get back on the road last summer. This summer, I will implement what I really want in that department.
I will try and post the graph in the next couple of days - I don't have a scanner but have a camera with very good macro capability, so I'll take a close-up snap.
Frustratingly, I won't be able to drive it again until next weekend though - its currently sitting on a manky set of original steel wheels (with complementary flat tyre) courtesy of Datsun Dave while the real ones are being refinished.
tel240z
Club Member
Interesting that about running on, after my engine rebuild i have that problem as well, now i was led to believe that it was hot spots in the combustion chambers or a coked up engine hence it was called pre-ignition, can anyone explain why it would make any difference by retarding the timing a couple of degrees, i know ford used a fuel shut off valve in the carb to overcome pre-ignition