projectcar
Anyone got any swap recommendations for a mgb, im looking for a similar size i4 thats a bit more modern with a power output of 150-200hp
Discussion
Mazda miata will fit right in.
K swap
This. Basic k20a2 will be plenty of high revving fun. Way better than any of the other 4cyl options, with an immense aftermarket.
The zetec is meh. Miata's 1.6/1.8 is also meh. The b series are becoming increasingly more difficult to find, and as mentioned above, spin the wrong way.
Backend the K20 with a s2k trans and you got basically a s2k without the f20/f22 pricetag
Thats makes a load of sense, thanks, should be perfect around the hp mark too with room to expand if wanted later
Just budget $10k if you do it yourself. Hardest part is all the little things you need. Fittings, hoses, adapters... Ie. Having a NPT fitting when you need a BSPT one, which prevents you from dropping the drivetrain back in place, can be endlessly frustrating.
And an awesome character. Loves to rev, but not overly peaky. Honda K20 really is a fantastic engine
I have seen people slap eBay turbos on junkyard k20/k24 motors and make insane power. Or you can modify it N/A with a lopey cam for that classic sound and still make respectable power. So yeah I agree the k-series is definitely the way to go.
I feel like a 250hp NA would be mint. Any more and you may tear the chassis apart
That would be ideal before needing chassis reinforcement. Which I would look at options as soon as possible or at least while you are in there. I’d hate to make that power at the chassis’s threshold and then have to rip it all back out to reinforce.
Just for my curiosity as a project car enjoyer more than a project car participant (lol).. when I see these comments I'm always curious, that are you looking for in the chassis, and what would typically be modified to support more power?
Some cars are unibodies or have subframes. If you can beef up the existing structure then do that. Companies make stiffening kits for this exact thing. You can take ideas from that and make your own without chopping off a limb to buy a few pieces of sheetmetal. Otherwise, there are ways to create a frame under the body to completely stiffen the chassis. Or you can cage it, but I don’t recommend that as a casual daily.
Ahhh ok. So like, welding in material to "thicken" areas, and maybe adding tube steel as bracing from side to side, etc?
Appreciate the response!
That’s right. Most cases I’ve seen were welding in extra sheetmetal like with gussets or beefing up frame rails on the floor pan. Sometimes it can be a simple bolt on piece. Like this one in a Miata (https://www.roadster.blog/2015/08/mx-5-roadster-nd-chassis-bracing.html?m=1)
It just depends on the application. There is likely information somewhere on specifically OPs car on suggested ways. I’m just speaking in a general sense.
The dangerous “well im in there”
Haha. I mean more to be forward thinking about it. But yeah you can go down a deep dark rabbit hole when it is your car.
K series are really tall though due to their valve train, so keep that in mind, might need a modified frame/subframe to fit under the hood.
Or a dry sump kit…..
Yea depends on the budget and goal I suppose.
I did a deep dive on this not long ago, there is a company in the UK that makes K series swap kits. If you dig deep in some of the MG forums you can find some K swap build pages. It all looks straigh forward buy if I remember correctly there is a difference in overall height for different K series motors that needs to be taken into consideration.
K20 or k24 is abundant in the yards, mated to a CDO9 adapters are out there .
You just need the motor and trans to get the suspension geometry of an s2k? TIL
pedantic - Wiktionary, the free dictionary https://share.google/HcO7LN9U6uzmzYpEp
Was originally thinking b16 because they are cheap as hell, not sure what box to pair with it though. Heard mk1 supra fits well but they are super expensive nowadays
Apparently B series spin counter clockwise so that would be the trick. Lots of K swap options if it physically fits, that would be my choice.
Yeah the B series would be much more of a pain for that reason. My vote is for the K.
I was given a B20 for mine but as others said it spins the wrong way
Ended up getting a 2.3l eco boost I’m going to drop in Making a ladder frame reinforcement and using a 9” rear
Toyota 3SGE if you want 8000rpm and that classic rally rasp in the higher rpm's. They are reliable, anywhere from 140 to 200hp depending on what generation of 3SGE you pick.
You can also do some headwork and get 9000rpm.
I'm beginning this swap into an RX8. Do you have any experience with this engine swap?
Not specifically swapping 3SGE's, but I've owned a whole heap of Celica's and Rav4's with Gen 1 3SGE, GEN 1 3SGTE, Type G and Redtop 3SGE Beams.
The FWD style motors can still be used in RWD applications, you just have to account for the throttle body position. Or use a blacktop beams from an Altezza. I prefer the 1st gen 3SGE motors, they are simpler than all other gens once TVIS is removed and quite reliable. They are the easiest to make rev high. Yes... They are the lowest on power at 130hp stock (about 150-160 wheel with cams, headwork for 9000rpm and a haltec each).
Red Top beams are the best of the lot if you can find one.
Also... Just for shits and gigs, I've been seriously considering swapping a 1.9TDI diesel into a RX-8. Useing a PD150 tuned upto 200 wheel, 50+MPG's, ultimate reliability, low rev limit, low down torque. Exact opposite of what an RX-8 is expected to go.
In europe judging by the background?
I'd go with something that already comes with a transmission or has stock transmissions for your setup available. M111 Benz, BMW M44, Volvo red block, Mazda B16, Ford DOHC or Zetec, maybe Opel Z20LET.
200hp is a lot for an na i4. I think it's either 120-150hp or forced induction.
Yea im in England, i dont mind sitting at 150 tbh as i really mostly care about it being light weight
What about a four speed from a 1.3l manta and some higher output Opel small block engine from a 90s Corsa GSI?
I'm not very knowledgeable about Fords sadly.
I think 200 is doable with Opels C20XE (non turbo previous gen(?) Z20LET) or at least I have seen claims around that number with itbs. You could also get close to 300 with the even older CIH 2.4, but youd need a 16v head for that, which is crazy expensive.
C20XE is a good call. I forgot that OP doesn't have to use these ultra rare Manta 1.8S Getrag 240 boxes. I'd stick with a stock engine though. Most performance oriented, na i4s are already more peaky than you really need in a street car.
Agree on the stock engine. Is there a difference between the 240 for the 1.8 and the one for the 2.0? Because I thought 240s werent really that rare (at least not in Germany)
The 240s are rare and super expensive. You need them to swap pretty every GM family II engine in older rws Opel models. The later five speeds out of the Omega are not.
I see, ty
'Busa motor
I’ve always wanted to put a 13b in one 🤷🏻♂️
I kinda want to run a 12a, if only for the vintage vibes. (And increased durability)
12a's are actually pretty hard to kill if you beat the hell out of them properly.
Mine had chunks of chrome the size of my fist missing from both rotor housings, and she still never skipped a beat. Hell, I bet it would still run if you didn't put any seals in it, they just find compression somewhere
SR20. My buddy swapped one into an MGBGT years ago and that thing is a hoot!
Came here to say this. SR20DEs are cheap and plentiful. Easy to maintain and service with tonnes of aftermarket support. Great NA ripper and sounds perfect on a peashooter exhaust so will fit the car.
4AGE.
Top answer right here. 4AGE would be dope, but unfortunately, not the cheapest. Thank the JDM fan boys for that.
Chevy 2.8l inline 4? 175hp 185ft-lbs
Toyota beams swap
This
Toyota 2ZZ-GE? Hits the power mark, and it should be readily available. It was even used in the Lotus Elise, so it kinda-sorta already has a connection with British cars .
2zz’s are pretty hard to come by that aren’t molested. Maybe 10 years ago
Sounds interesting, hight revving too so could be fun
If not a Honda K.... I really like the Mazda/Ford MZR stuff ---Later Miatas, Rangers, mazda 3, Focus, and...bang for the buck for without a turbo FUSION 2.5. Fusion sourced 2.5 is really cheap and a good start, they sell many of those there? Miata or Ranger gearbox and go....
Just for the noises.... I really like the VW 07k 5 cyl and you can buy 5 of them at $350 each in the yards here---because they sold a bunch of them and they really don't fail.... Lots are being stuffed into 944's and other longitudinal RWD cars so it's all been pretty well scienced out.
I do like the idea of a 5 cyl but i reckon the 2.5 would be a bit long for the bay? Same as the 2.5l fusion?
They put an I6 in the MGC, which was just a B with a bulge in the hood
2.5 fusion is still pretty short front to back, same cylinder head interchange as Miata 2.0 if that puts it into perspective.
I can get 07k dimensions but it's surprisingly short as well. Some of the 944 swappers should have good reference of it.
Forget practicality. Find a rotted out 1980's Fiat spider 2000 turbo donor car. I put a 73 Fiat twin cam in my Midget and I couldn't be happier. I'll even send you the fab files for the guibo to british driveshaft adapter. The Fiat 5 speed is lovely.
I reckon that might be a little bit too expensive for me but appreciate the offer 😭😭
Expensive? The twin cam motor/trans I bought was like $150 all in, probably another $300 in parts to make it run well.
Oh interesting sounds fun then lmao
Get real, the 3.5 liter Rover V8 is literally a bolt in for any B 73 or later, roadster or GT.
Or do one of those other swaps if you want to make a project out of it. If you want to drive the car and have everything work really well do the Rover.
She always will be a project car i take out on the weekends, and i do plan to get everything else sorted with the car and drive it for a bit on the stock plant, however after ive saved up a bit and done enough research it'll be time for the swap. I ideally am very avoidant of v8s as i really dont want to add more weight.
Honestly genius to stick with a carbureted setup, seriously cuts down on cost vs having to deal with ECUs and EFI. Do you have a build diary anywhere for this?
4 cylinder Ecoboost from a later model Mustang.
This is what I was going to suggest. 2.3L Ecoboost. Plenty of aftermarket support, get the transmission from the mustang while you are at it.
Mazda 12A rotary. I've seen it done. Rev to 8000 rpm. Only about 115 HP though. Way fun.
With a better intake, carb, header, and exhaust a stock port 12a can make 140 flywheel hp. With a large street port they can make around 200 and drive like normal
A friend of mine has a volvo b230ft in one, fun car. Very tight enginebay
Take a look at my post history. Im doing up a nice little 2.5 duratec in my 74 midget. Im adding a turbo to the mix, though.
Miata 1.8 solid engine and the best shifting 5 speed out there.
1.8t from an A4
Was trying to avoid turbocharging ideally because i want a more linear power delivery
But turbo go whoooosh
Not more modern but very reliable would be a BMW M10. With a bit tuning 200hp are no problem. But I don't know if it fits.
No way you're making 200hp out of an m10 with "a bit of tuning". Is it possible to make that power? Yeah, but it's gonna cost a bazillion dollars in parts and labor to build an NA race engine or a still pretty involved turbo set up.
Unless high compression, overbore, cam, manifold/carbs, race gas and an almost open exhaust is a bit of tuning, I would agree
Maybe junkyard merc/volvo motor?
Idk how much power they make, but feel the Mercs could be close
91-93 Volvo B230 can take a ton of power without touching the bottom end
I was just trying to think of rwd cars that I've seen in the junkyard recently. OP did mention wanting to keep it NA, so idk if the Volvo is there... A junkyard supercharger though....
If OP is in NL, like it seems, diesels are painfully expensive to have on the road. Technically this should be old enough to be excluded, but idk how that works for inspections
You can N/A a b20 with decent results, 100hp/liter is always an aggressive goal
Put in a Chevy 3.4 (or another 60° v6) is the best one overall and there's tons of documentation to help you. The engine is stuoud cheap and parts are super easy to get and work on. It requires nothing special at all about it and it will get you 160 and a fuck ton of torque. The motor makes you good power sounds really good and is stupid reliable. Plus it's mated to a t5 so you can gear it however you want.
If you want more power later it's easy to swap the heads and cam it you can get to around 300 wheel if you really want to. Or you can jump straight for the 3800 but that's a a bit more of a pain imo.
Just finished swapping one into a spitfire and with a mild cam + heads it netted me 200 whp in a 1600lb car.
I've never done it but if I were going to, I would do a Ford Duratec or Honda K24. I don't know what a RWD drivetrain looks like for either of those though, they're often in FWD cars but they're exceedingly common and good engines.
You can use the Sierra transmission with the Ford duratec. The duratec is an excellent engine. You can buy camshaft, computer, wiring kits and take them up to 270 horsepower plus in a 2 L. Ford made those engines 2 L, 2.3, 2.5, 2.6. The real runners are the 2.6 with the 2.3 crank.... The 2.5 and 2.6 cylinder heads are the better ones. They have bigger valves and a raised exhaust port....
Ford made that particular cylinder head with variable valve timing on the intake, variable valve lift on the intake, variable timing on the exhaust, and variable valve lift on the exhaust. But, they never put it on one cylinder head together. However, for about $1,200 in parts it's fairly easy to do(You need a computer and a harness and camshafts to do it).
I have seen the Nissan SR20DET in a few. Good aftermarket, sweet turbo noises... good combo.
A friend had a VR6 swapped MGB. Very cool but there’s some oddities with that engine like coolant hose routing.
Honda d series. All over the place and cheap to build
I've thought of this as well, but you'd have to run the diff upside down or something.
There's probably someone that can make a bastard plate to mate it to something. Not sure tho
Oh I'm sure, but d,h,f and b series Hondas run "backwards" so you'd have to do something funky unless you want 5 reverse gears.
You want something with unlimited engine upgrade potential- go Subaru BRX But if British is your vibe you should just jump to a jag convertible that fits your budget
I believe those even came with the aluminum Buick/Rover V8 for a short time. That would be my go-to.
Yea they did however i dont wanna mess with the weight distribution by putting a big v8 in it
Dimwit, it's a small all aluminum engine that weighs less than the 1.8 liter iron block "B" engine. Or anything with an iron block. And about the same as the aluminum block 4 cylinders.
But suit yourself. At the stock displacement of 3.5 liters (215 cubic in) 200+ HP is readily available, and the later 4.6 liter (281cu in) Rover versions come with a low profile EFI and 230 HP stock with 270-300 as realistic inexpehsive goals.
Or have fun a 4:cup swap and all the fabrication and adaptation required. If you like engineering stuff go the DOHC 4 valve 4 cylinder. If you want an inexpensive bulletproof rocket, go with the Rover.
The Rover V8 is a well-known MGB swap. There are a half-dozen forums for MGB's and they all have an engine-swaps section.
Buick Fireball V8
K series, but I'm biased with one in my B.
Have you got any more details about your swap by any chance?
Since you're in the UK, the 1.4l TJET from a wrecked 500 Abarth could do
I know you said i4, but its fairly common for people to swap in a GM 3.4L V6. Idk why, but thats just how it is
Have you thought about a rover 3.5 v8?
K swap Honda.
Not a single person has said Ecotec, so I vote a Solstice/Sky powertrain. LNF and AR5 would be plenty
MGExperience has a whole forum dedicated to MGB engine swaps.
Mazda FE3, complete mitsi evo wiring harness and turbo, courier gearbox
2.0T LTG/6 speed manual combo from a Camaro or ATS. 259 hp factory but you can always dial back the boost until you want more.
13b, K20, 2ZZ
A Fiat 500 Abarth engine. Makes fun noises and lots of aftermarket support for it. Grab a trans from the Fiat Spider or Abarth Spider drivetrain and go for it!
Can't tell if you are in Europe or the UK, but the Zetec has a HUGE amount of performance parts available to you because of their wide use in kit cars and escort engine swaps over there. Easy enough to chuck in a RWD car and a great lot of fun (ignore anyone saying its not a "fun" motor, yeah its no rev to 12000 but its a great engine).
Other option to be a bit insane would be something like a volvo 5 cylinder, but it may be slightly too big, and will for sure be more difficult to RWD.
Rotary. Lol I have a friend from college that did that swap
Vauxhall red top C20XE. Plenty of them out there for cheap, only a bit more modern, huge aftermarket support, and decades of tuning knowledge. 150hp stock and you'll be well into 200hp by the time you're spending much money. Plus it's a UK boy racer's dream
Dude fiat abarth 124 spyder engine and trans would be interesting
Toyota 3sge beams best bang for buck
Ford ecobeast crate motor.
Something Honda with side draft Dellorto carbs.
3SGE Beams
Stuff a B48 in there and have way too much fun
Sr20ve vvl with s13 transmission
Kawasaki zrx1200r engine, turbo it
Never see it mentioned... So Suzuki M15A. Might be lower power than you wanted, but there are ways to fix that!
1000cc motorcycle engine would be my pick if I could find a MGB near me for a reasonable price
VW 1.8T is 225Hp out of the box and is easy to tune to 400Hp. You could also look at a nicely ported rotary as they are very low weight and high hp options that could run sans ECU and are carb'd.
I'd think about your appetite for sorting the electronics and fueling. A lower power but more commonly done swap at a lower hp might be the easy button depending on your degree of expertise.
I'd be going with a Miata 1.8L or a K24.
I like seeing people put inline merccruiser motors in these i was looking at doing it next but sold the car. Boat motors seem to be able to run full open better.
Are you in the UK? I'm not sure how well it would fit but the MG Kseries with VVC makes 160, or up to 175 with a couple of basic mods and a tune. Its what MG would have put in it if they restomodded a classic, and I think it would suit it
I think your biggest issues with any swap will be the driveshaft, but you can get them custom made if needs be
I wouldn’t build a Frankenstein car. Do a built up MG engine and trans
Ford Zetec is pretty popular with the caterham guys
Is that the 1.6?
They were 2.0's too I believe.
Ah okay, would you have any idea what box would be best to pair with?
There's a guy on FB that sells converter plates so the Zetec can be married up to an RX8 gearbox
The ford type 9 bolts straight up to it. Plenty of swaps done with that combo into cortina’s and escorts in the uk, so I’d start with forums for those
You'd have to do some research on that
Sierra gearbox for zetecs
This or one of the various Toyota inline-4 mills. Lotus used a lot of Toyota mills.