Type R and VTEC owners

Muffin` said:
96 is cast iron!
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You're not going to gain much if anything with the 98 spec mani. It might even be worse in some areas being a 4-1 vs a 4-2-1.

You'll save weights but that's all you can be sure of.

You just spent loads on the car, don't waste it on a mani for the sake of it :p

saitrix said:
It's a manifold, I don't care how desirable it is, just how well it flows. :p
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Exactly!

More JDM names and products does not equal cool or better in any way.
 
-Ad- said:
You're not going to gain much if anything with the 98 spec mani. It might even be worse in some areas being a 4-1 vs a 4-2-1.

You'll save weights but that's all you can be sure of.

You just spent loads on the car, don't waste it on a mani for the sake of it :p
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The 98 is 4-1 and will give increase mid-range torque over the 96, and the same peak bhp. Honda increased the mid-range on the 98 because of the larger wheels and difference in ratios to allow it to be as fast as the 96. It's also lighter, he will see an improvement with the 96 but he will see a bigger improvement with the 98 with the UK's similarities to the 98 in wheel size and gearbox ratios.


-Ad- said:
More JDM names and products does not equal cool or better in any way.
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JDM names go on a better product, could always stick with TEGIWA or DC :eek: :D
 
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Always makes me laugh when people all go on about weight saving on their car but never weight saving on themselves. :p

4-2-1 will give you a better spread of improvement but with lesser affect than a 4-1, which are more focused on a certain rev range. You can work it all out easy enough what revs they target by measuring the length from exhaust valve to join in the manifold. You can work out the speed of the pulses in the exhaust flow, and thus the timings of the pulses for all parts of the exhaust. I would imagine at joins you would want one to be low pressure when the high pressure pulse comes from the other pipe joining, so to give a scavenging effect. From memory (going back 3 years here since working with this type of thing) the exit velocity of the gasses change with rpm, so you want different length sections so it times all of this correctly, so a 4-1 only having a single length its tuned for will only give improvements due to this at certain revs whereas a 4-2-1 would give it (to a lesser effect) at different revs.

Also on a side note, the 4-2-1 is meant to have better clearance and I do ~25 speed bumps a day.
 
Well it's pretty well known rule that 4-1 = peak bhp and 4-2-1 = mid range torque or 'drive ability'. The 98 is a 4-1 and offers more mid-range torque than the 96, it's simply a better unit.

96 134lb ft @ 7200rpm
98 137lb ft @ 6200rpm

Is your car lowered? I'm on a 25mm drop and my splitter will hit anything first.
 
The changes on 98 Spec isnt soley due to the exhaust system. Did the 98 spec also pick up slightly more compression?

IIRC there is also a subtley different cam profile. I had a cast 4-2-1 with JDM 2.5" collector (2.25" ID ;))on my B16 Rover. Nice £60 buy from an EK9 owner.
 
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Muffin` said:
Well it's pretty well known rule that 4-1 = peak bhp and 4-2-1 = mid range torque or 'drive ability'. The 98 is a 4-1 and offers more mid-range torque than the 96, it's simply a better unit.

96 134lb ft @ 7200rpm
98 137lb ft @ 6200rpm

Is your car lowered? I'm on a 25mm drop and my splitter will hit anything first.
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Well when you say these two thats fine but just remember that not all 4-2-1's act like that.

And yes but I have seen they go for £200 vs sub £100 for the '96. 3lb/ft worth it for £100? :p

MilanoChris, Going good thanks, had the cambelt all sorted etc, needs an oil change any week now, going to have to force myself outside with the cold. :( Still enjoying it though, and with a tiny bit more power it should be really good. Only thing now is to improve the brakes as I have had brake fade with those pads on it.
 
Which pads are on it? Still them Ferodo street ones? Remember the lines are 13 years old, so it might be worth investing in some braided lines and also getting the fluid changed unless you've done the fluid yourself.

I had a look on Pistonheads the other day, decent condition UKDM DC2's are still going for way over 4 grand, they're holding their value really well.
 
Yeah still those Ferodo's. On my list was some braided lines and when the weather improves I was going to give the brake fluid a flush. I've only done it a few times on country road but still a little nerving when it happens. :p


Muffin`, Car is stock height, just its those square shape humps so rather not take the risk.
 
saitrix said:
And yes but I have seen they go for £200 vs sub £100 for the '96. 3lb/ft worth it for £100? :p
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£200 for a 98 :eek:

Seen aftermarket 4-2-1's go for £150...



funny you should day that I've just got back from my new flat and the underside caught when leaving the carpark and then I hit my front splitter on the road outside :mad:

Good thing my twinloops not on yet :rolleyes:
 
Muffin` said:
The 98 is 4-1 and will give increase mid-range torque over the 96, and the same peak bhp. Honda increased the mid-range on the 98 because of the larger wheels and difference in ratios to allow it to be as fast as the 96. It's also lighter, he will see an improvement with the 96 but he will see a bigger improvement with the 98 with the UK's similarities to the 98 in wheel size and gearbox ratios.


JDM names go on a better product, could always stick with TEGIWA or DC :eek: :D
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Unfortunately it isn't that simple, wish it was.

For example, how come the Comptech manifold (smaller ID" ~2") performed as well or better than all other manifolds in the Great Header Test? Better mid-range than all the Branded 4-1 with large collectors (bar the Toda) and peak power around the same as well.

It's not down to the ID" at the collector or even the OD" as a lot of people seem to think: 'OMG 2.5" OD Collector means moar powers innit!' Remember a manifold or exhaust cannot give you power, the exhaust from the manifold does nothing but lose power. All we try and do with exhausts is try to minimise these losses and tune the engine for what we require, mainly with the manifold design.

People can harp on about 4-1 and 4-2-1 and collector girth, but well designed primaries are where it's at. If the primary design and flow is bad then nothing you do further down the system will suddenly bring those losses back.

Jonnycoupe said:
The changes on 98 Spec isnt soley due to the exhaust system. Did the 98 spec also pick up slightly more compression?

IIRC there is also a subtley different cam profile. I had a cast 4-2-1 with JDM 2.5" collector (2.25" ID ;))on my B16 Rover. Nice £60 buy from an EK9 owner.
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Speaketh the truth.

It's never as simple as bolt on X, get Toot or bolt on Y and get Tootastic!
 
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-Ad- said:
Remember a manifold or exhaust cannot give you power, the exhaust from the manifold does nothing but lose power. All we try and do with exhausts is try to minimise these losses and tune the engine for what we require, mainly with the manifold design.
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You are wrong there actually. Scavenging it is called, it is where you time the low pressure pulses going from the exhaust tip up to the exhaust valves correctly. You want the low pressure to be at the exhaust valve at the exact time of opening the valve, this then effectively sucks the waste gasses out of the cylinder quicker. Look it up in a vehicle thermodynamics textbook if you want more info.
 
Don't worry , I know a little about scavenging and pulse tuning (not much though:p). There is a an awful lot to think about with the exhaust system, be it optimising exhaust gas flow rates, backpressure, scavenging and the gas pulses exhausted into the system.

But I doubt some of these aftermarket manufacturers have put much thought into it to be honest and just take a standard design, play around a little to get some good dyno figures, then stick their name on it and flog it for £££.

And unfortunately many people buying such so called 'upgrades' for their exhaust just think: 'Larger OD" = Less Restriction = Better Flow = More HP' and you cannot explain the complexities to them as they know best ;)

Looking at getting a nice new system on my Teg in the coming months and to get the Comptech mani on to replace my UKDM POS! Still a bit buy and bolt on, but I'll be doing some calcs and speaking with the man building the system as part of the group buy so we can get a good system at a reasonable price for the forum users. It's never going to be perfect for everyone, but my car is being used as the pilot/jig so it's all gravy :D

Pop along into the 'repacable carbon silencer thread' on itr-dc2 if you're interested.
 
I have to be careful with exhaust choice for myself as I do a lot of motorway driving. I do want to make my car sound better when in vtec though, currently it's totally stock except for resonator removal (got flexible piping to feed cold air still).
 
I've been offered a CTR for 2 grand from a guy from work. Silver 53 plate, 108k, service history up to 80k then self serviced after that (putting me off slightly) not had a chance to drive it yet. As long as it doesn't have any major work looming I might be tempted to use it as a run about for the next wee while. Been thinking about selling the 350z so this could be an ideal stop gap until I get something else.
 
They are hovering between £2.5 and £3.5 for that sort of mileage. Depending on the condition it could be a good buy.

Just make sure the steering rack isn't noisy, the clutch has been changed and the tensioner checked along with the usual.
 
I may belooking at a CTR soon - re clutch - how long do they normally last (concerned about MilanoChris's comment above) ?

I'd have expected themto be pretty durable ? my 1.8 VTI is driven in a very spirited manner (often to the 8,400 redline) and its still on original clutch (with no untoward signs currently either) - at 157k - ok its a warm vs hot hatch - but I'd have expected the CTR clutch to be similarly bullet proof ?
 
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