sylva_phoenix

Hi, I've just joined having read a few interesting threads, particularly on the fabrication side of things and selecting the right turbo for the 1.8 Miata engine. I have a full bodied kit car, similar in design to a Lotus 7 / Caterham or Westfied, but a little prettier. It runs a tuned ford xflow, 8v pushrod motor, which doesn't sound very impressive, but it'll take it from 0-60 in about 4.5 and shake your teeth out on the way! There are some photos in my album.

Anyway, the plan is to replace this classic motor with a 1.8 and gearbox from the Miata (MX-5 over here in UK) and then strap a sensibly sized turbo to it using a custom designed, homemade manifold and run it on a standalone ECU, such as Megasquirt or Omex. I'm looking for 200rwhp, but with minimal lag for road course driving. The car only weighs 530Kgs, so it doesn't need any more power than this.

Cheers, thanks for having me.

Laurence

94mx5red

iTrader: (14)

Car looks awesome.


Throw some pictures in this thread, most are too lazy to go to your album.

rleete

iTrader: (21)

That is a cool looking ride. Post some pics of the bare chassis if you have any.

Braineack

iTrader: (62)

Welcome, sylva_phoenix!

turbofan

iTrader: (1)

Looks awesome! I think you're definitely on the right track with your plans and it sounds like the car will be absolutely insane when you're all done. Good luck!

Saml01

iTrader: (9)

Why a 1.8 from a miata when so many better motors are out there?

sylva_phoenix

Thanks for the welcome. Reasons for choosing the mx5 engine are several; 1 its a sweet revving twincam, which was based on the bore and stroke of the original Lotus twincam, 2 its very tuneable, 3 it requires no modification to run it longitudinally, 3 there are lots and lots of them out there, 4 parts are cheap, 5 there's a lot of information about how to do the swap, 6 it comes with a free, really strong 5-speed gearbox and finally, its cheap. I considered a few other engines, Ford zetec, vauxhall redtop, rotary, even an alfa v6. This seems the most practical choice. Fitting a turbo is probably overkill, but what the hell......

Regards

rleete

iTrader: (21)

years ago, I drove a locost style car that was less than 1600 pounds with about 250 HP. It was very low, and felt insanely quick. Having 200 HP in a car weighing 500 pounds less would be crazy.

sylva_phoenix

Ha ha, correct.

It will be equivalent to a caterham r400/r500, but with about 25% more torque. At a 5th the price.

turbofan

iTrader: (1)

don't you dare leave us hanging without video when this is all said and done.

sylva_phoenix

You get "police camera action" on BBC US, right?

turbofan

iTrader: (1)

I don't have a TV service currently, I get my BBC fix off Netflix. Should I search that show out?

EO2K

iTrader: (37)

I wouldn't go calling the Miata 5 speed "really strong" but for 200hp in this ultralight, it should be just the ticket!

I like you already!

Please, please, PLEASE!!! Post some more pics!

Also: How hard is it to find parts for late 70's Triumphs over there? I need an intake plenum for a 1974 TR6 2.5L PI

sylva_phoenix

TRIUMPH TR6 PI AIR INTAKE & FILTER BOX? | eBay

sylva_phoenix

That link is nothing to do with me, just something I found on eBay.co.UK. sorry if I'm not supposed to post links to items for sale.

Cheers.

EO2K

iTrader: (37)

Nah, you're cool. There are almost no rules around here about that kind of stuff, unless you are spamming. That's an interesting interpretation of "good secondhand condition" haha! That's like $16 in USD, but I'm sure shipping would kill me. Thanks for the link!

That crossflow looks like a damn neat little motor. 1100, 1300 or 1600? We didn't get those in the US in anything, as far as I can tell. Looks like the engine in my friends Spitfire 1500, other than the obviously superior crossflow design. Also, tell me those are 38 or 40mm side draft Webers so I can hate at you

What version of the Mazda BP are you looking at?

sylva_phoenix

It's a 1660cc xflow, 8 valve all iron pushrod. This was standard issue in the ford Escort from '75 onward and pretty much formed the staple diet in terms of budget racing in the UK for about 10-20 years. It was fitted in formula Ford, rally cars, 750MC, hillclimbing, sprinting, grass-track everything really.

Mine's had a lot of work, mainly by the guy I bought it from 10 years ago.

High lift 254 CAM, flowed head, lightened and balanced bottom end, 6 spoke flywheel (2.9kg including AP sintered clutch), 1300cc machined pistons to increase CR to around 10.5:1, Unleaded, ported head, double vavle springs and light weight valve train, Bryan Hart dry sump system and, no they're not Webers. They're twin 40 Dell'ortos. It revs to about 7500rpm, but that's pushing it on standard crank and rods. Transmission is a ford Type 9 from a standard issue travelling salesman Ford Sierra running a Mk2 ecort live axle with 4.1:1 LSD. Almost all 7 type cars in the UK use the Type 9 box, hence my comment about the mx5 transmission being "strong". It's all relative.

Cheers

sylva_phoenix

I was looking at a 1.8 VVT engine from a mk2.5, but I'll take any advice you offer. VVT seems like something to go wrong that isn't really necessary.

Cheers

turbofan

iTrader: (1)

Haha indeed the Mazda transmission is at least a bit stronger than the T9 Ford box. I used to play with Merkur XR4Tis and many would swap the T9 for the Mustang T5.

I would say that for your build you don't need to spend the extra money for the newer VVT engine. I'd go with a '99 engine -- good head, crappy exhaust but you'll be scrapping that anyway.

EO2K

iTrader: (37)

I shall bring the hate Anything has to be better than the damn emissions spec Zenith Stromberg 175CDs on my 6.

I really hope you start a build thread here, or give us a link if its offsite.

Edit: VVT all depends on what you want to do to control it. You can do a super basic DIYPNP and run a BP4W (exactly like I have in my car) or you get the VVT BP6D and step up to a MS3, AEM or something like DIYAutoTune's VVTuner to control the VVT. Bonus points on the VVT motor is it runs higher compression (in the US anyway) and will make a shade more power out of the box. You don't have to control the VVT out of the box either. We have a few guys running the BP6D (01-05 US) head on a BP4W (99-00 US) bottom end on the stock BP4W ECU and it seems to do fine.

I think in EU/UK, you guys got the BPZ3 instead of the BP6D as the VVT engine, so the specs may be a little different. From what I've read, the BP4W is still the same though.

BP4W if you want simple, BP6D/Z3 if you want to make the investment to support the VVT, but you can always do this later.

Do you plan on building an engine, or just running something from a wrecker?