Exhaust manifold question

[Smithy18]

Alright lads, i've just brought a 98spec B18C6 UK ITR engine i'm going to drop it into my EK4 VTI-S. I'm unsure on what exhaust manifold i need ( standard manifolds )

I've been looking at the 98 spec 4-1 JDM manifold which sounds like its the one to get. As my car is not a jdm import i take it i wont fit correctly ?

Any help would be nice lads, what manifold do i go for thats a direct fit for a B18c6 in the EK4 ?.

thanks

 

[donzo]

B18C6 is the UK version and uses a 2.25 collector manifold so your exhaust on your EK4 will fit. To upgrade to a 2.5 JDM manifold your cat/decat will need to be swapped over as the bolt spacing is different and another exhaust will be needed unless you get your one modified as the JDM cat is shorter.

 

[Smithy18]

thanks for the reply, So i could use my b16 manifold on the b18c6 ? is the b16 manifold more restrictive than say a uk B18 manifold ?

 

[Barryl85]

The OEM B16a2 manifold wont fit i'm afraid mate its too small (height wise)

B18C6 engine is taller

and also if it did fit it would be restricting power, you want a manifold with a 2.5" collector for optimal exhaust velocity.

 

[Smithy18]

Thanks for the reply guys, so to run the 98 jdm spec 4-1 ill need to replace my cat. any suggestions on a decent de-cat pipe ?

cheers

 

[Barryl85]

I'd personally get a custom one made up - thats what i did and it was great for alignment as i could move the two bolt section that mounts to the collector and was a great fit.

Off the shelf ones dont tend to fit properly or you get one of those adjustable legnth ones that are very leaky.

I'd decide on a cat back system aswell so you know what legnth to make your decat (unless your sticking with what you got already)




Did you ever find out what was wrong with your B16A2?

 

[Smithy18]

I'd personally get a custom one made up - thats what i did and it was great for alignment as i could move the two bolt section that mounts to the collector and was a great fit.

Off the shelf ones dont tend to fit properly or you get one of those adjustable legnth ones that are very leaky.

I'd decide on a cat back system aswell so you know what legnth to make your decat (unless your sticking with what you got already)




Did you ever find out what was wrong with your B16A2?

Thanks for your reply, I'm not sure what places around my area can do this sort of thing any suggestions ?.

At the moment i have a SRS G50 catback, i don't have much of a budget left after buying the b18c + s80 lsd, for the moment mabey i will have to buy a UK b18c exhaust manifold to bolt strait up to what i have already.

The b16a2 is being removed on sat, its pretty much out just sat on its engine mounts. I'm also intrested to know what went wrong i'll strip it down when its out and post some pictures up.

thanks again.

 

[Barryl85]

As far as getting the decat made up just use any custom exhaust maker in your area - they should be able to make one up for you in no time.

UK ITR manifold is gash mate - heavily restricts the engine, UK ITR only produces 187bhp (on paper) and thats because of a few things.

UK ITR Manifold 2.25"
UK ITR ECU (fuel/air map is toned down to produce less power than the JDM)
UK ITR Exhaust system 2.25".

The JDM ITR makes the power it should (around 200bhp) with a 2.5" manifold + exhaust system + great air/fuel map on the ECU.

If you rectify these restrictions even on the UK ITR B18C6 engine (internally its exact same as a JDM 98 spec B18C) e.g. getting a 4-1 2.5" manifold - Using a JDM P73 ECU - running a decat & decent cat back system you should see 200+ bhp easily.


Obviously if you are on a budget you may have no choice but just take all of that into consideration, which ECU are you going to run?

 

[Tegiwa Imports]

All UK oem B-series manifolds are 2.0"
Them being 2.25" is a MYTH!!!!

JDM siR manifolds are again only 2.0"

The only 2.5" manifolds are EK9, 96spec & 98spec ITR

Everything else is 2.0" and Honda NEVER made 2.25"

 

[Barryl85]

all uk oem b-series manifolds are 2.0"
them being 2.25" is a myth!!!!

Jdm sir manifolds are again only 2.0"

the only 2.5" manifolds are ek9, 96spec & 98spec itr

everything else is 2.0" and honda never made 2.25"

Sorry if i was a 1/4 inch out and anyway.....

SIMMER DOWN !!!!!

 

[Smithy18]

As far as getting the decat made up just use any custom exhaust maker in your area - they should be able to make one up for you in no time.

UK ITR manifold is gash mate - heavily restricts the engine, UK ITR only produces 187bhp (on paper) and thats because of a few things.

UK ITR Manifold 2.25"
UK ITR ECU (fuel/air map is toned down to produce less power than the JDM)
UK ITR Exhaust system 2.25".

The JDM ITR makes the power it should (around 200bhp) with a 2.5" manifold + exhaust system + great air/fuel map on the ECU.

If you rectify these restrictions even on the UK ITR B18C6 engine (internally its exact same as a JDM 98 spec B18C) e.g. getting a 4-1 2.5" manifold - Using a JDM P73 ECU - running a decat & decent cat back system you should see 200+ bhp easily.


Obviously if you are on a budget you may have no choice but just take all of that into consideration, which ECU are you going to run?

Well in that case it may be worth spending the extra money, The plan then as follows -

JDM P73 ECU
4-1 98 JDM spec
Custom De-Cat to fit.

Whats a fair price for a 4-1 JDM mani and a jdm p73 ecu ?

thanks for the advice.

 

[oldmanitr]

USDM ITR = B16b type r cast iron manifold, they are the same 4 to 2 manifold, the downpip is 2.25" in the USDM for 1998 to 2000 on the ITR and 2.5" for JDM ITR, got no clue on Civic ITR but assume it is 2.5" OD. Id is much smaller. Sure it is made by "Acura" so maybe Honda never did make a 2.25" exhaust. LOL, Acura sure did.

BTW I'm looking for a 1996 -JDM ITR exhaust manifold, the actual cast iron piece. All USDM ITR, and B16 CTR run a smaller? manifold in terms of runner diameter. The 1996-97 JDM manifold has: bottom shield bolt in line with exhaust stud, black outside shield, and the 4 to 2 cast iron pipes are seperated till the reach the bottom flange (all others are cast into a single external lump with support ridges).

Oh and the US ITR puts out 195 SAE HP vs 197 DIN HP, the US ITR has smaller downpipe, .5 lower CR, smaller cat, maybe smaller B pipe, maybe smaller muffler (the Futuba 1028 is only 2.0" just as the pipe goes in the muffler and all Type Rs I've seen have the same Futaba 1028 stamped on the end plate. I have run both the JDM 1997 4 to 2 to 1 header vs 4 to 1 JDM OEM replical header. There is not a whole lot of top power there. 4k to 7k torque is way up... and the USDM ITR may have a 2.25 OD down pipe but ID is something short of 2"...

http://wiki.clubcivicquebec.com/index.php?title=Integra_Type_R

If you scroll down you will see a 1996 -97 JDM exhaust manifold, the 1998 ITR USDM and CTR are the same manifold and differ from the JDM by having the tubes all in one big hunk of iron.

 

[KieranEG6]

Arnt the US ITR's 187hp. I always seem to see them clamed as the same 195hp as the JDM. How can an engine with lower CR, smaller exhaust and mapped to account for lower octane fuel be the same base figure at the JDM ITR???

I think a few american salesmen are fibbing along the lines here lol.

P.s I know its only a few hp but just irritates me when claims dont add up

 

[oldmanitr]

Most US pump fuel can support a good bit of CR, so I don't know what the actual JDM timing would be at. I do know most tuners in the US don't advance timing on the ITR. .5 CR is not a whole lot, the .25" exhaust is a lot, but you would be surprised how small all ITR / CTR exhaust ID is at the flanged like the B pipe to rear muffler. Something like 1.9" ID. Since backpressure is related to the smallest point... you get the idea. I have the Stock USDM ITR exhaust after the cat and a small portion of the B pipe (which is also sub 2" ID). One day I'll upgrade to a 60mm Apexi system.

stock GS-R do a 1/4 mile in 15.2 to 15.6, a ITR can do the same in 14.6 to 15.2, so the ITR has to be putting out the 25+ HP. Rolling road GSR 150 to 155 and the ITR USDM 170 maybe even as high as 175 SAE.

I"m always surprised how much HP that NA cars from the factory can put out from stock exhaust systems. My LS1 Camaro with headwork, mild cam, lid, tune put out about 375 engine HP thru the stock 2.75" exhaust and the muffler has an internal baffle of 2.5"

AFAIK the UK ITR has a tube header and all 4 to 2 to 1 Honda headers that I know of all twin wall, so the internal tube size has to be REALLY small on the 4to2 part of it. Anybody know the ID?

 

[KieranEG6]

What is the octain rating of pumps in the US?? Thought it was somewhere between 85-90.?

I know about the factory JDM Integra R and CTR cat back exhausts are ALL 2.25 (57.5mm) external diameter, FACT as i ordered a center section for a JDM 98spec ITR and measured it. Also they even go down to 2" at the small silencer into the rear back box. The whole JDM are 2.5" is a myth. The only thing sized to 2.5" is the collector flange size i.e the size of the donut gasket used on the manifold. The main difference is in the actual piping shape and bends, the JDM section are bent alot more smoothly.

The UK ITR 4-2 part doesnt have a twin wall i dont think just a mass produced crapy pipe thing.

I dont realy see where 1/4 mile times can have rellavance, my Standard EG6 Sir2 ran 14.2-14.5 with just an exhaust.

I just think its really weird and annoying when people always claim US ITRs to be 195hp jus like the JDM when they are fitted with an inferior engine tuned to run on lower octain fuel. UK ITRs are 187hp and the only difference is the exhaust and ECU tuned to a little bit lower octain. Jap is supposed to be like 99 and our base is 95, super is 98.

 

[oldmanitr]

What is the octain rating of pumps in the US?? Thought it was somewhere between 85-90.?

Pump 93-94 AKI is at every fill station in most of the USofA, this is identical to "Superplus" 98 RON

I know about the factory JDM Integra R and CTR cat back exhausts are ALL 2.25 (57.5mm) external diameter, FACT as i ordered a center section for a JDM 98spec ITR and measured it. Also they even go down to 2" at the small silencer into the rear back box.

OK, I'm not confused, right ALL of them go to 2" OD just as the pipe goes into the Futuba 1028 muffler. ALL JDM, UKDM, USDM, etc. The USDM pipe back there is 54.7 mm OD. I 'm not sure if the JDM is 54.7 or 57mm, but I would think all do go down to 2" OD.

BTW, this even makes more to the point, the USDM has a 2.25 at the end of down pipe, cat and the front of the B pipe, is this bad dunno, all go down to 2" ath the entrance to the rear muffler....

The whole JDM are 2.5" is a myth. The only thing sized to 2.5" is the collector flange size i.e the size of the donut gasket used on the manifold.

Amen

The main difference is in the actual piping shape and bends, the JDM section are bent alot more smoothly.

Look to same to me ITR vs ITR, the non-VTEC exhaust seem a whole lot more crush bent. Anyway compared to an Apexi WS stock is weak. I say the restrictions on a Honda are at the B pipe flange..

The UK ITR 4-2 part doesnt have a twin wall i dont think just a mass produced crapy pipe thing.

My experience is that all Honda stuff is twin wall with the internal tube crushed when the external tube is bent. ID of most Honda tube headers is far smaller than external size. It would be nice to provide that. I can provide USDM data, and 1997 JDM ITR size.

I dont realy see where 1/4 mile times can have rellavance,

stock engine, independent test shows the USDM ITR about .5 seconds quicker in the 1/4 mile, that takes HP. Simple physics.

my Standard EG6 Sir2 ran 14.2-14.5 with just an exhaust.

And my non-stadard Challenger does is the low 12s, What's the point?

I just think its really weird and annoying when people always claim US ITRs to be 195hp jus like the JDM when they are fitted with an inferior engine tuned to run on lower octain fuel. UK ITRs are 187hp and the only difference is the exhaust and ECU tuned to a little bit lower octain. Jap is supposed to be like 99 and our base is 95, super is 98.

See here for octane:
http://en.wikipedia.org/wiki/Octane_rating

I make no claim, Honda and the SAE make the claim. I do claim stock ITR USDM put down about 170 wheel HP SAE and can do the 1/4 mile in the high 14s, which using any online 1/4 to HP calculator will show that the engine is at 185 to 190 HP. I would agree that the true HP for across the board comparison for the ITR USDM is more like 187 HP. As the Honda drivetrain really only has about 10% drivetrain loss. So one should see rolling road just at 170 of slightly below.

Also note any 1/4 mile calculator is going to base the run as average HP under the curve, so this will have a tendency to over rate peak HP of supercharged engines and large displacemnet engines with flat torque curve. A peaky engine and none are more peaky than a ITR will be under rated, so that would be say a few more peak would be closer to true peak HP. We all know it ain't peak HP that moves a car right.

I will say that the USoA over the last few years has gone to Ethanol and engine HP is down 3.3% just because there is less energy in Ethanol. That is 7 HP right there. Yet the 12 year old ITR spanked the new SI in a performance test, assuming the SI can use the new fuel better. We can all thank Al Gore and UK prof Phil Jones for burning our food and producing less HP, but that is a whole other can of worms eh?

http://www.insideline.com/features/1998-acura-integra-type-r-vs-2010-honda-civic-si.html


OK Lets say your Civic with exhaust runs the 1/4 in 14.4 I show the curb weight of a EG6 to be 2200 US pounds so 2400 race weight. You don't list MPH or tyre, so I'll guess drag radials and MPH would be something like 96 MPH. Crank the numbers and we get:176 HP

http://www.dragtimes.com/horsepower...ubmitButtonName=Calculate+Horsepower+Estimate


USDM ITR
http://www.dragtimes.com/horsepower...ubmitButtonName=Calculate+Horsepower+Estimate

I have a chip tune waiting and with the ITR JDM 4 to 1 and an Apexi WS 60mm exhaust, I'm expecting 180 to 185 rolling road HP. About 198 to 204 engine HP. funny we are talking round error HP, while American V8 we talk about ball park ranges of 25 HP...

 

[KieranEG6]

It means all.

So does the US ITR and JDM have the exact same exhaust systems?

As for the quarter mile times my point was they cannot be used to compare anything really. There are way to many variables, like tyres, pressures, air temp, and launch surface ect.
According to your calculator My 14.22s, 102mph run on street tyres. weighing in at 2425lb (1100kg) That would make my standard B16a 183hp??? with just an exhaust bolted on??

I wasnt really having a go at you, just the whole myth in general as eveywhere you look there are different answers, "supposed" facts. Sorry i just like to rant about this kind of stuff. lol
In general terms and aproximate base figures
JDM ITR 200ps
UK/US ITR 190ps
regardles of quarter mile times and brocher numbers

Oh and Sorry for the thread jack.

Well in that case it may be worth spending the extra money, The plan then as follows -

JDM P73 ECU
4-1 98 JDM spec
Custom De-Cat to fit.

Whats a fair price for a 4-1 JDM mani and a jdm p73 ecu ?

thanks for the advice.

A JDM p73 ECU are a little pricy second hand. Around £100. A p30 or p28 chipped and mapped with a Std Jdm base map or with a custom map would be alot more suited but could range in price. Chipped with base map only cost me £40 on my P30 ecu. custom would most likely cost in the range of £200-400 depending on who does it.

Think the 98spec 4-1's can be found for round £200-300. Or you could jus buy the Tegiwal toda replica for a bit more at £410 and apparenly give even better gains allround.

As for the decat a custom one with a baffle 2.5" collector size and piping would defo be you best bet. Plus cheaper than buying one to suit, as ant decent exhaust place should be able to make you one up for around £50-70

 

[Smithy18]

It means all.

So does the US ITR and JDM have the exact same exhaust systems?

As for the quarter mile times my point was they cannot be used to compare anything really. There are way to many variables, like tyres, pressures, air temp, and launch surface ect.
According to your calculator My 14.22s, 102mph run on street tyres. weighing in at 2425lb (1100kg) That would make my standard B16a 183hp??? with just an exhaust bolted on??

I wasnt really having a go at you, just the whole myth in general as eveywhere you look there are different answers, "supposed" facts. Sorry i just like to rant about this kind of stuff. lol
In general terms and aproximate base figures
JDM ITR 200ps
UK/US ITR 190ps
regardles of quarter mile times and brocher numbers

Oh and Sorry for the thread jack.



A JDM p73 ECU are a little pricy second hand. Around £100. A p30 or p28 chipped and mapped with a Std Jdm base map or with a custom map would be alot more suited but could range in price. Chipped with base map only cost me £40 on my P30 ecu. custom would most likely cost in the range of £200-400 depending on who does it.

Think the 98spec 4-1's can be found for round £200-300. Or you could jus buy the Tegiwal toda replica for a bit more at £410 and apparenly give even better gains allround.

As for the decat a custom one with a baffle 2.5" collector size and piping would defo be you best bet. Plus cheaper than buying one to suit, as ant decent exhaust place should be able to make you one up for around £50-70

I've brought myself a JDM 98Spec ITR 4-1 manifold with a adjustable 2.5" De-cat pipe. Still undecided on the ECU i've got a £200 budget for the ECU at the moment. I'm unsure if i should save a little more money and find myself a Spoon ECU From what i can gather the Spoon ECU is the best BOLT ON mod i could do on a budget.

Anyone had any experiances with the Spoon ECU for the B18CR/6 ?

cheers

 

[oldmanitr]

It means all.

So does the US ITR and JDM have the exact same exhaust systems?

Different from 02 in downpipe to just after the B pipe flange the USDM ITR is about 54mm external. JDM pipe I believe is 57 MM.

USDM and UK look to be the same from the cat back.

Does anybody know if the UK ITR header is twin walled and what is the internal pipe size?

USDM, 97 JDM, CTR all have the same iron manifold and it is 1.2 x 1.3 interanl on the 4 ports, the 2 ports measure at 1.65 ID.

As for the quarter mile times my point was they cannot be used to compare anything really. There are way to many variables, like tyres, pressures, air temp, and launch surface ect.

Maybe I should say these are weight and MPH to HP calculators.

According to your calculator My 14.22s, 102mph run on street tyres. weighing in at 2425lb (1100kg) That would make my standard B16a 183hp??? with just an exhaust bolted on??

Make sure you use race weight (curb + driver + fuel). 102 MPH is good BTW.

 

[KieranEG6]

I've brought myself a JDM 98Spec ITR 4-1 manifold with a adjustable 2.5" De-cat pipe. Still undecided on the ECU i've got a £200 budget for the ECU at the moment. I'm unsure if i should save a little more money and find myself a Spoon ECU From what i can gather the Spoon ECU is the best BOLT ON mod i could do on a budget.

Anyone had any experiances with the Spoon ECU for the B18CR/6 ?

cheers

Yes the spoon ecu is a good bolt on, BUT for the price of one you could get an even better custom map, there are plenty of People who chip and map p30 ECU's in the uk.