B18 engine differences (one for the Honda geeks)

Soldato
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So then, if anyone here is able to list the differences between the B18(c4?) found in an MB6, and the one found in a DC2 Type-R I would greatly appreciate it.

From what I can gather, there's the cams, light valves, valve springs, higher comp. pistons.

Thanks :)
 
Oil pump, crank, rods, pistons, valves, valve springs, cams, LMAs, head casting, rocker cover, inlet manifold, throttle body, exhaust manifold, flywheel. That covers the majority of it, I could probably be more specific if needed?
 
Thanks, not for now but I'll bear that in mind.

Sounds like basically everything is different. Would you say it's unrealistic to try and chase Type-R power from an MB6 engine then?
 
Wasn't the gearbox one of the problems with the MB6? Crappy ratios etc?

Wheres that traitor Gaijin?:p
 
It depends really, i've had an eg9, dc2 and an mb6 and the mb6 c4 is the worst vtec engine i've used to be honest.

As standard they are pretty limp, if I was after cheap power i'd probably get a b18c4 bottom end b16a2 head, cheap 4-1 exhaust manifold and a chipped ODB1 ECU mapped to suit. That should see you fairly well as a cheap starting point.

What are you thinking of doing?
 
Wasn't the gearbox one of the problems with the MB6? Crappy ratios etc?

Wheres that traitor Gaijin?:p

Yup, they drop out of vtec between first and second, nasty boxes, i'd prefer a b16 box over one even though they have an open diff.
 
It depends really, i've had an eg9, dc2 and an mb6 and the mb6 c4 is the worst vtec engine i've used to be honest.

As standard they are pretty limp, if I was after cheap power i'd probably get a b18c4 bottom end b16a2 head, cheap 4-1 exhaust manifold and a chipped ODB1 ECU mapped to suit. That should see you fairly well as a cheap starting point.

What are you thinking of doing?

It's not for me, I'm asking on behalf of a friend. He has an EK4 and an MB6 you see. The MB6 is rotting and will be fit for scrap soon enough, he wants a hot B18 in the EK4.
The EK4 already has fancy extractor and intake manifolds along with a bunch of other go faster bits. I think his idea was to get some money back by selling the B16A2, but if using the head from that on the B18 bottom end is the best way to go then he might alter the plans. The B16 is a bit miley and smokes in VTEC though, that's just valve stem seals though right?

As for the gearbox, yes, the idea is to use a 98 spec DC2 box, but failing that it will be the B16 open diff'd box.
 
The smoking is most likely to be either stem seals or worn piston rings. If the MB6 doesn't smoke or use oil, then i'd basically take the bottom end off that and put his old head on with a new set of stem seals, that covers most bases, it would make a pretty nicely performing car though, depending on setup it could possibly be nearly 200 bhp ~130 ft/lb. I'd do it if I were him, but then I know I could do it myself quite easily.
 
200bhp you say, that sounds just the ticket. I'll tell him later on, thanks for the info!

If that was the plan, would you need anything special in the way of head gasket/studs? What ECU would you need for the OBD1?
 
200 is the top end of what's available really, that's being generous, anything over 180 should be fine though.

You'd need a standard 81mm head gasket (£38 ish from the dealer) and the head bolts (£unsure, i bought ARPs) and timing belt (£30) from a b18 engine. It should bolt together fairly easily.

For the ECU he would need to have a socketed/chipped ODB1 ecu with a conversion harness to plug into his ODB2 loom. All of that is pretty much readily available from a load of places. Have a look on xenocron.com for a good starting point. Once all of this is installed there are a few software tuning options: Crome, Uberdate, Neptune, ECTune to name but a few.

It's all been done before and is pretty well documented so I can't see it being much of a head ache.

Ohh, he may need a new exhaust manifold if his is from a b16, and the b18 block is taller and the shorter manifolds can sometimes catch the sump.
 
Nice info neil-ste!

B18 into an EK is always going to be good.

I have 2 x B18 exhaust manifolds lying around if your mate needs one Clarkey, a standard UK Integra Type R one and a Standard Integra Si one.
 
Wasn't the gearbox one of the problems with the MB6? Crappy ratios etc?

Wheres that traitor Gaijin?:p

Coooooooooooooooooooeeeeeeeeeeeeeeeeeeeeeeee
gayfight.gif
:D

Oil pump, crank, rods, pistons, valves, valve springs, cams, LMAs, head casting, rocker cover, inlet manifold, throttle body, exhaust manifold, flywheel. That covers the majority of it, I could probably be more specific if needed?

Probably covers the majority of it, also most of the earlier B18C, C6 had a hand ported and polished head. Believe it was done by machine on the later models however.

It's not a bad engine at all, less raw with a dual stage/runner inlet manifold to increase torque in the mid range. VTEC engagement is far less pronounced on the B18C4 than a type R lump.

As discussed the S9B gearbox has pony ratios but does have LSD. I had both the 4.785 FD (Post 98) S80 and the 4.4 FD (Pre 98) in my car and I'd say I preferred the 4.4. Not by much, but from memory, 4th & 5th seemed a bit shorter and a more natural progression from the earlier gear.

As with most Honda engines, tuning wise, you pay very much for very little.
 
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Thanks, not for now but I'll bear that in mind.

Sounds like basically everything is different. Would you say it's unrealistic to try and chase Type-R power from an MB6 engine then?

Jonny got 200hp out of his B18C, this had the benefit of the dual runner inlet manifold, so a much better midrange power curve. It was also quicker than the Type R.

Can't remember the exact mods, but it had the ITR manifold and a 2.5" collector, decat and ITG filter along with one of his modified ECUs.
 
The thing is though, Jonny had an Sir(g?), which are only about 10 bhp down on a standard B18c and don't come with the stupid gear ratios that the MB6 B18c4 is crippled by. I seem to remember Jonny saying he had a P28 or P30 ecu too. There is never going to be a night and day difference with regards to turn of pace between it and a Type R.

Clarkey, tell him to get it done! You've got me interested in looking for another eg9 now :(
 
info on those manifolds mr xplosion??

edit: bleh, 2.25" collectors?

The UK mani is 2.25"

The Si one is bigger, the UK manifold wouldn't fit our standard Teg exhaust.

I could measure it for you if you like but it's nothing fantastic.
 
Thanks, not for now but I'll bear that in mind.

Sounds like basically everything is different. Would you say it's unrealistic to try and chase Type-R power from an MB6 engine then?

Nah,

You just need to get a decent OBD1 P72 ECu on it.

My JDM B18C made Type R power and 20lbft more at 5k. Dual runners for the win. Would be great in an EG or something as a circuit car.

My friend ran 185bhp in his c4 engined Rover 216 but his wiring was a bit dicky so the IAT was reading really cold and it was running rich, particularly when the IAB's opened.
 
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The UK mani is 2.25"

The Si one is bigger, the UK manifold wouldn't fit our standard Teg exhaust.

I could measure it for you if you like but it's nothing fantastic.

the JDM one is 2.5", no clue about the Si though unless it's the standard 60mm
 
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