J32Vic

Thanks for the welcome fair enough, it's understandable sticking with what you know and already have to hand. The architecture of the engine may lend itself to tuning, but breathing is the primary issue and given that the only other J engine in the UK is the aforementioned Legend J35, options for improving air intake is pretty limited. I've been on the lookout for a J35A8 intake for some time from the UK, in that time I've seen one engine available and the seller didn't want to split it. I'm also unsure about just how well the A8 intake lines up with your J30 (it lines up with my J32, so it may be possible). If you go for boost, of course you'll be looking at more power, but given how much you could invest in the plumbing and mapping necessary (you mention being hands on, not sure if that includes ECU work) you may as well go for a US engine.

For reference, my J32A2 is considered a strong and high revving unit by J series standards (7k redline), but it needs uprated valve train components to go much beyond that as the springs just aren't up to much more than that.

Something else to consider - the alignment of the intake. The larger engines allow for the intake to be spin 180 degrees, making it much more suitable for a RWD platform, not sure if this is possible with your J30.

If you're after more information and a better knowledge base than I can supply, take a look at j32a.com (I hope linking to other forums isn't against forum rules, I've not seen it be an issue here or on other forums). It's essentially a complete and comprehensive information source for J swaps. Granted, it's primarily for FWD cars but it can't hurt to have a mosey over and look around!

Edit; the J30 is actually shorter than the F20 so if anything the balance should either stay the same, perhaps even lead to a 49:51 weight distribution.

Nick Graves

Virtually all US Honduras use the J35 - or J37! The one to go for. Cheap over there and pretty bullet-proof.

You'd be better boosting the F20C in reality; the J was designed (like the VR6) for compactness (it's tiny!) and the problem with a V-layout is that the tight cylinder bore spacing limits the main bearing area; it's nowhere near as strong as an F20C. In the US, it's reckoned ~400BHP is the max.

See here:

Pilot or Odyssey J35A

Is the RHD clutch master cylinder location a problem?

CynicG

This should be a good thread - keen to see it pan out.

Here's some motivation from Haltech

Nick Graves

As is evident from the photos, the C32 (well, C35) is problematical.

Being a 90° V6 with early fat DOHC VTEC heads, it's very wide compared to a J-series. I believe a brake servo & clutch M/C in RHD form might be problematical.

You will also need TBs, because the air feed is from the rear and cannot be reversed easily, as it can with some J-series.

A C32B will cost you a fortune, too. Actually, probably not if you can find a C35B from a KA9 Legend...

surfer_crx

J32Vic - cheers for the link, I'll have a better look at it when I've got time but it can't hurt to have too much info. You are right about the intake not being able to be rotated, however depending on how much room I have under the bonnet I will either make my own or stick some ITBs on there. The original manifold has very long and narrow runners (I assume this is to get the torque) I can assume this is what makes it hard to get power up top with it. As for being hands on that is pretty much everything except I don't have my own rolling road yet so I still have to hire the dyno but do the tuning myself, but first I need to build the ECU (Megasquirt 3).

Nick - I understand what you are saying about the F20, however this is a low budget project done with the intent of just having something to do in the garage on a weekend rather than doing it for the sake of trying to get more power or better driveability than the F20, I've had a boosted F20 and it was fun but I enjoyed building the kit and tuning it more than I did driving the car. I would really like to see if I could get the J30 up to 240 BHP NA which should be fun as it will still have 30% more torque than an F20.

Nick Graves

Yes, I understand you're nuts!

I was more making the point that if you get too deep, it won't be a cheap project any more. I like the idea of building it out of other people's rubbish.

If you're sticking with a J30, its advantage is its 86 x 86 bore/stroke (same as a K20) so it will rev sweeter and easier. 240BHP is easy from stock.

One problem - the J30s usually had a dizzy on the back of the right cylinder bank, whereas the bigger ones had coil packs. That really will be a hassle for inline...

surfer_crx

86mm pistons are cheap and plentiful and if I select the right ones I will be able to get a healthy bump in compression too (in theory) I will probably end up swapping the dizzy for coil on plug ignition as they are cheap enough now and the Megasquirt will allow for it with relative ease.

My biggest concern after obviously getting it fitted and running is the NA tuning aspect and yeah it can be quite costly as you've said, it's something I will look at when I get to it. It might be more cost effective to go for a bigger unit from the states, time will tell.

noodels

What about the gear ratio if the j tops out at 7k leave as is ?

har-vey

love the idea of this. don't get me wrong I love how the s2000 is a screamer but it would be cool to have a nicer soundtrack

surfer_crx

Yeah I think the standard gear ratio is perfect for a car that tops out at 7k


I love the sound of a standard F20, but yeah I do think the V engines sound a lot nicer with an exhaust than the 4 pot does.