civic 1.8 vti

Jonnycoupe said:
Sorry if that came accross a bit blunt but on Honda R this week theres been about 4 thread over this MB6 issue with the gearbox and a guy called Stuart the fish who preaches on about having to do this mod.... which is like £600. So its becoming a fashion accessory for this car rather than people actually driving the car and developing how THEY want it to drive. I must also point out this is the 98 spec one, this 96 spec has a similar 2nd gear drop.

Let me try to explain. The MB6 has a different head from the ITR and difference characteristics. BUT it has a far closer 'brother' and that is the Integra Si which is essentially the same engine other than the Si compression is 10.6.

Now this engine has 178bhp over 169 in the Civic. Right from the start we can see how the Civic really isnt optimised for output, its pretty shy from the traditional 100/bhp B-series DOHC VTEC area too. Aswell as what i can only assume to be very conservative ignition timing the VTEC and IAB (dual runner stage -Inlet Air Butterflies) are at the wrong points too. The delaying of VTEC to 5800 area would be to delay the wild profile VTEC cam for emissions and economy reasons and the off VTEC cam giving the favourable swirl from the two inlet valves opening a slightly different amount. The MB6 VTEC and IAB are set inversely to the Si settings so its not like changing the VTEC point will be detrement to the engine at all.

Now, my car has the same engine as the Si (its an SiR-G) and throwing the ratios into an excel sheet i have pretty much the same drop and infact my 5th is slightly longer. Now at no point driving my car have i ever been concerned about the 2nd gear drop (around 8100rpm to 4800) changing from 1st to 2nd. Its more than tractive from 3500 and certain very eager to climbe the tacho. Only difference would be the engine output so thats where id focuse my efforts on a Mb6. Getting hold of a ECU from a Integra Si that you can chip or even use Hondata would be less than £600 and you are future proof for future mods (ie a set of cams, exhaust etc can all be catered for)

This is why I get a bit irritated hearing this MB6 + ITR box y0 talk, it mainly described as awesome by some chap who seems to only consider his car as a drag racing machine. The Mb6 box is well suited for the road, nice sensible gears for cruising and darting about. Also whilst were getting to factual stuff the only thing the ITR and MB6 have in common is the block, oil pump and sump.

VTEC @4400 and IAB@ 5750

a) no problem with VTEC that early
b) no need to worry about gearbox drop, infact the longer first at 38mph or so will provide more tractive force than a ITR at 38mph in 2nd gear, and first gear is struggling for grip on the MB6 so no need to make it shorter and next to useless.

Case complete.
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Do you know I was thinking what a great post you had just made until you slipped in the troll section at the end. Shame you couldn't have made this post at the start of the thread instead of causing the bad vibe that you have.

I'm sorry i seem to have offended you so much for putting a integra box in my car. I will stand by my point that it improves the car drivability and makes the car much more fun to drive whilst making the acceleration better. Making the acceleration better on my car does not mean that i consider my car as a "drag racing machine", a statement which is utter speculative drivel, made purely on one given scenario i described in another thread :rolleyes:

You do seem to know your stuff, and there are questions I would like to ask you about various things. But I don't wish to derail this thread any longer if all you are going to reply at me with is condescending and rude remarks.
 
No no no, the guy i mean is this Stuartthefish guy over on HondaR, its almost to the point where hes pushing the fact you HAVE to fit an ITR box to an MB6. If you have chosen to fit one after driving one thats cool, but this guy is telling people thinking of getting a MB6 that they have to get an MB6 is what i can only describe as an intimidating manner. But when asked why you need to fit a high value rare component to a cheap car he can only come up with the drag racing scenario. My experience of the 'potential' of a mb6 'ish' engine is that the gearbox is no stumbling block at all, just focus on the engine as a whole package rather than playing with gears designed for a car that revs a almost 10% more.

FWIW that power curve is mine :)
 
Jonnycoupe said:
No no no, the guy i mean is this Stuartthefish guy over on HondaR, its almost to the point where hes pushing the fact you HAVE to fit an ITR box to an MB6. If you have chosen to fit one after driving one thats cool, but this guy is telling people thinking of getting a MB6 that they have to get an MB6 is what i can only describe as an intimidating manner. But when asked why you need to fit a high value rare component to a cheap car he can only come up with the drag racing scenario. My experience of the 'potential' of a mb6 'ish' engine is that the gearbox is no stumbling block at all, just focus on the engine as a whole package rather than playing with gears designed for a car that revs a almost 10% more.

FWIW that power curve is mine :)
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Ok mate, sorry for the undeserved bashing in that case, thought you were digging at me :) - i've done a bit more reading on Honda revs and i'm impressed with your input over there :) Perhaps you should have a chat with Stuart The Fish? :p

I particularly noticed your comments about the P72 vs Unichip arguement. The P72 does make sense but I don't think I'll have access to the facilities to fit/tune it. I know the IAB's/dual runner and the high VTEC point is a botch up, but will a unichip with a lowered VTEC point make any good out of it?
 
I seriously wouldn't spend more than £3.5k on one, get a 99 one if you can, preferably above 65k miles or so, so it has had the belts done and won't hit you with that for quite a while because that is an expensive job.

I'd definitely recommend a decent exhaust system, my system has made the car a lot more responsive and the sound is gorgeous under acceleration :cool:

Edit: Joined Honda Revolutions myself and I noticed that guy StuartTheFish pimping the DC2 ITR box transplant. I'm not up on the technical side of things but he seemed to make out like the car was crippled unless you put one of those boxes in :confused:
 
thebrasso said:
Edit: Joined Honda Revolutions myself and I noticed that guy StuartTheFish pimping the DC2 ITR box transplant. I'm not up on the technical side of things but he seemed to make out like the car was crippled unless you put one of those boxes in :confused:
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:D Thats indeed the very point, i think you need to drive one before deciding to go that route.

Unichip can control VTEC and i guess you could get a simple rpm switch for the IAB's, or get an aftermarket intake manifold such as a Skunk2 or Blox for the 'Integra GSR' and as there single stage intakes you can go for the unichip much like any other VTEC install. I think i have the longest 5th gear of the VTEC B's and i find it too short, i think its the longest cos VTEC is the lowest rpm point 90mph+ = VTEC.
 
If I was going to do anything I would just lower the VTEC trigger point to say 4500 rpm. With the standard ratios on the VTI at legal speeds you wouldn't be sat in VTEC, just. But the car would be a bit more responsive. IIRC 70mph in 5th on mine is just under 4400rpm I'd have to check.
 
thebrasso said:
If I was going to do anything I would just lower the VTEC trigger point to say 4500 rpm. With the standard ratios on the VTI at legal speeds you wouldn't be sat in VTEC, just. But the car would be a bit more responsive. IIRC 70mph in 5th on mine is just under 4400rpm I'd have to check.
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Yeah, I think it's similar with mine at 70mph. So what is the optimum point to have the VTEC and IAB's at? Is it both at 4500rpm or similar or is it better to have the IAB's opening later?

I don't think i'll go down the skunk manifold road as I want to keep the car as standard (or as easy to return to standard) as possible as i'm only intending to have it another year tops.

Cheers
 
If you pull the vacuum pipe of the actuator (and plug the pipe) then the IAB throttles remain open all the time. I tried it today, just to see if it made a significant difference but my (doubtless poorly calibrated) butt dyno couldn't make out too much difference to be honest, though I didn't do a back to back comparison.
 
Gaijin said:
Ok mate, sorry for the undeserved bashing in that case, thought you were digging at me :) - i've done a bit more reading on Honda revs and i'm impressed with your input over there :) Perhaps you should have a chat with Stuart The Fish?
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Gaijin, the whole Stuart The Fish issue, shall we say has been going on for ages, and across a couple of forums, and if I remember correctly, is long and varied. Suffice to say STF does come out with some ludicrous tosh.

Jonny doesnt need me to vouch for him, as you've found out, his technical posts are superb. ;)
 
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