Basic B20 build questions

Hey guys. Im considering upgrading to a basic B20 setup for my DC2 VTIR and want to ask a few (actually alot) of questions in regards to my build.

I am considering the following setup:

Stock B20 Bottom End
P72 B18c Head
Rod Bolts (ARP??)
Head Studs (ARP??)
Cams (ITR??)

Spoon Header
Intake Manifold (Skunk 2, edelbrock Victor X or Performer X??)
Intake (comptech ice box)
Throttle Body (68mm??)
Mugen twinloop axelback
Hi flow metal cat

ECU (Hondata S200/300??)

I already have the Intake, Header and Exhaust which im intending to use to save money.

1. Firstly, anybody have any opinions/critisms on the selection of parts i have chosen for the build. Any feedback would be great! I need as much info as possible :)

2. Will my Comptech intake be compatible with an aftermarket IM and TB setup as suggested above?

3. In regards to cams, are there any cams which are slightly more aggresive than the ITRs which do not require the valve springs etc to be changed?

4. Would a 68mm TB be suitable for a basic setup like this?

5. Any thoughts on breather kits for B20's and if they would be necessary? (as i have read B20's do not have breather boxes?)

Thanks guys :thumbsup:

ek9 cams and camshaft are more aggresive... i dont think ud need to change valve springs and retainers to change those ... but you might as well since your gonna be doing it....

and the list of parts you got there seem fine to me are u going to be using standard itr injectors?

id guess that the intake would not fit if u were to go for a bigger TB but , im not 100% sure with that .. im running a bigger skunk2 TB and iv just got a custom cai... does the job fine :)

oh.. and i heard tri-y header setup was one of the best ... but everyone has diff opinions .. and you've missed the golden eagle vtec conversion kit about 300-350$

Oh i didn't know the EK9 cams were more agressive then ITR. Thanks for the info!
As for injectors, i'm not sure what size injectors would be suitable. Would standard DC2 vtir injectors be enough or do i have to upgrade?
And yes, ive accounted for the GE VTEC conversion kit. standard item for this setup so i thought i wont list it.

Im pretty sure the late model ITR and CTR cams are exactly the same. Since the motor is apart i would change piston rings, check rod bearing, mains, notch the pistons, ARP rod bolts. Standrad injectors will be fine.

Look for some b20 builds on here, power ranges from 110-130kw atw.

Thanks Fatboyz39. I will be looking into freshening up the motor once its apart.

My 5 cents worth is as follows:

Keep the standard VtiR intake manifold (Just clean it up inside a little)
Don’t go bigger than 65mm in the throttle
Sort out the piston fly cuts when they’re out
If the budget permits, do the rings, bearings & gaskets too...

Put the money from the manifold into bigger cams & suitable springsRe breather: We use this one… http://www.theoldone.com/components/breather/
Or you can make the same from Morosso parts and a few other bits for a bit less...

Stock B20 Bottom End :thumbsup:
P72 B18c Head :thumbsup:
Rod Bolts (ARP) :thumbsup:
Head Studs (ARP??) No need for stock build
Cams (ITR) :thumbsup:

Spoon Header :thumbdwn: Use Tri - Y design headers
Intake Manifold (Skunk 2, edelbrock Victor X or Performer X??) Stock is fine
Intake (comptech ice box) :thumbdwn: Get a custom Long Ram Intake 70mm, make sure you get a good filter
Throttle Body (68mm) :thumbsup:
Mugen twinloop axelback Get a custom 2.5icnh from Headers back
Hi flow metal cat :thumbsup:

ECU (Hondata S200/300) Crome is cheaper




3. In regards to cams, are there any cams which are slightly more aggresive than the ITRs which do not require the valve springs etc to be changed? Use stock Vtir Vavle train with the cams is ok


4. Would a 68mm TB be suitable for a basic setup like this? Yes 68mm is ok


5. Any thoughts on breather kits for B20's and if they would be necessary? (as i have read B20's do not have breather boxes?)

Buy the fittings from Honda for the block and get a cheap catch can setup

what about a b16a head?? is there any difference

im looking at doing one for a ed civic

what do u mean by the piston fly cuts???

if it was me im however goin turbo aswell... but if i was id use the 4-1 headers it has a better scavenging affect..

Thanks guys!

Could someone explain what piston fly cuts mean?

Also TODA, when you say save the money from the IM purchase for larger cams, do you mean larger cams than ITR? If so, what cams do you recommend?

The pistons flycuts or valve releifs in the B20B or B20Z standard piston,
Are too small for the B16/B18 Vtec head.
That said, with standard cams, there is no problem...
The problem exists / occurs when cams of greater lift & duration are used.
In this instance, the valve, which is larger than the valve releif in the piston,
Can / will contact the piston.
Addressing the valve relief or flycut solves this potential failure point.
NB: The main focus of this is the intake side.
This addressingf of the flycuts means to either enlarge them by hand with a mop or similar or drop them off at your local machine shop to be done properly.
The radius of the cut needs to be inceased, not the depth so to speak.

As for cams,
You won't go wrong with a set of TODA Spec B's

Very interesting. Another thing i will have to look into.

For my intended budget i was aiming to keep my standard valves, springs etc, Therefore looking at the most agressive cams that would suit. Would TODA Spec A's be applicable?

However, If i do save the money from not purchasing an aftermarket IM, what would it roughly cost to up grade cams, springs etc?? PM if you wish.

Piston's will definately need the valve relief cut. Do it right the first time around.

For stock valve train, ill stick to ITR cams at most. I wont go any bigger than ITR cams