lander

Hallo
Has anybody experience with this engine? MF204, build from B20A engine?
It has restrictor 26mm and I am looking to get more hp. When I remove restrictor, what other parts I have to change? Of course retune it on dyno.

alterdcreations

I am assuming the entire engine was built around the restrictor so i am stumped. i would say induction and exhaust first and maybe different cams.

if that is what your working?
very unique

Furyof4

I don't think you're going to find many people with direct experience with that engine. I would contact user DonF on here though. He may have some info or a contact of someone who does.

Aquafina

iTrader: (3)

I wonder when those engines were originally used if the drivers knew they were just econobox Prelude engines...

FerreiraCompetitions

This is going to be like any other restricted engine. Make as much torque before the restrictor chokes the power. Its the same in the Formula Atlantics 1.6L no need for restrictor, 2.0L+ needs restrictor.

The main thing it will be the profile and timing of the cams and possibly the head ports. Intake and exhaust are also probably length tuned to the powerband that the engine operates.

It all depends on what you want to do with that engine, hill climbs, track events, etc...if you're removing the restrictor I assume you wont be running it in F3 period. The engine without the restrictor and a remap will make more than enough power already and with good reliability. But just watchout those engines need a rebuild every 20-30 hours.

lander

I am building that Dallara F394 Honda Mugen. That engine is absolutly new, but I have also another engine before repasion and that engine I want to make more powerfull.

I had F394 Fiat Novamotor, but crashed it heavy :-(((


Yeah, that formula is for hillclimbing, but not for class F3 but for E2 where is no restriction for engine, this is why I need much more power.

When I will separe the second mugen engine on parts, I will post pics. I hope that you help me to find corect cams, valve springs which will fit that engine. Retune on dyno is no problem.

Filip

92TypeR

First, what are you using for engine management? MOTEC? DTA?

As Ferreira said, assuming internal engine geometry is identical to other B20A engines, the intake, exhaust, and camshaft profiles are the three most likely modified components to achieve peak torque before restrictor choke.

From my experience on restricted engines, longer intake runners and shorter exhaust runners are used to lower the engine speed at which peak torque occurs.

I would begin with modifying the intake and exhaust package. If you have some time before your next race, remove the camshafts and have them measured. Report back to us on the lift, duration, and lobe center numbers.

Can you please take more pictures of the sensor package for the cam/crank pickup? It is located on the gearbox side of the intake cam. Also, the dry sump package is interesting, can you please take some pictures of the bracketry and feed/return setup?

If you really wanted to go wild, you can run a B-Series VTEC head on that block. That would really net you some power.

alterdcreations

i didn't think that the vtec heads bolted on to the 3 gen lude b20a

92TypeR

Oh, I thought all the B-series heads were interchangable... I thought it was the A20's that were similar geometry but no-go on the swapping.

lander

For now, it has "stock" F3 ecu, old Bosch ms 2.2. But of course for retune engine I need new ecu system. Nice will be ECU with launch control and traction control. Everything depand about price. I can have for good price Ingitech ecu which is used on race bikes and I used it on my Suzuki Swift Kit Car, but that ecu dont have launch control and traction control. Maybe DTA ecu? Motec is too expensive for me.

That rebuilded engine can be installed during next season, no problem. For testing and start of season i will use new F3 engine, no problem.

I am going to make pictures what you need. There is no way how to modify intake system, only make bigger hole to air box (sorry, missing pic of huge air box). About exhaust, no problem to make new exhaust system. I will meassure cams, when it will be possible. How about valves? Valves springs? Retainers? atc?

Thank you for help.
Filip

92TypeR

I have used DTA S-series ECU's for a while, and they are very reliable and feature-packed for the price. They are very popular in Hill-Climb. The S-60 has launch control and traction control, but only has provisions for two wheel-speed sensors for the TC, so you can only utilize % difference front to rear. The S-80 has 4-wheel speed sensor TC, with in-cabin aggression adjustment. They are reasonably priced, much less than MOTEC.

For the intake, I would think you can cut the runners shorter right next to the mountings tabs for the fuel rail.

You should only need to worry about valvesprings and retainers if you plan on running a larger cam than the current one, or exceed the current maximum engine speed by significant amounts.

DonF might know more about the MF204 and what cylinder head geometry they use. I am assuming the motor turns clockwise?

lander

Pictures:
oil pump
http://lander.tuning.cz/images/2009/mugenF3engine/1.jpg

intake cam sensor
http://lander.tuning.cz/images/2009/mugenF3engine/2.jpg

crank sensor (removed but you can see it where it has to be, this is spare F3 engine for rebuilding)
http://lander.tuning.cz/images/2009/mugenF3engine/3.jpg

Valve springs, cams (i removed cams cover, as you can see it has double valve springs, meassured cams lift and it is 12 mm (on both cams), on valves of course it is more when I see the mechanismus)
http://lander.tuning.cz/images/2009/mugenF3engine/4.jpg

lander

Yeah, S80 will be very nice.
You are right, there is really way how to make intake shorter, but how much to cut it?

It has double vavle springs, of course I am able to meassure it how much resistance (or how to call it have them), but that engine has rpm limit at 6800, so if I will have to change valve springs, where and which to buy? and also I think that retainers need to be replaced.

Yeah, clockwise.

pr0honda

i remember seeing the b16a engine at donf's that turned clockwise.. he had one of the atlantic race cars in his shop when i first went there like 9 years ago.. its nice seeing real race cars.. don may know more about your engine.. give him a call in the afternoon time.. 904-378-4480

gotta run dry sump system since the oil pump would not work very well going the other way lol..

the DTA S60 is pretty nice.. i have a S60 and the older E48.. right now i am running the E48 since it was already in the car i bought.. i purchased the S60 awhile back for another swap and didnt finish it.. i will be selling the s60 with a wiring harness for a b-motor..

lander

I am now studying software for S60 and traction control is not good for formula, because you have to specify ratios to ECU and I have to change very often ratios. :-( S80 is what will be better way.

night

don't call don. make him come here. i wanna follow this conversation :D

and a VTEC head can be put on a B20A, ludespeed did it long ago, but it was a lot of extra work. and with an engine and racing level like this i don't see the point.

lander

I am looking for easyst way to get more hp from that engine without spending lots of money.

Filip

92TypeR

New cam profile, revised exhaust manifold, shortened intake runners, retune.

Traction Control, Launch Control, etc - will take seconds off your times, but I would focus on the essentials first, then revisit your engine management.

lander

But if I will have to retune engine, I have to change ECU system! Because as I writed, on engine is prehistorical "stock F3" ecu system BOSCH MS 2.2 , which is not possible to tune in this days.

OK, If I will need new cams, is it hard to get them for that head? How can I be sure that the cams will fit? Sorry, I am experienced with building Suzuki Swift G13B engine but Honda engines are for me absolutly new thing.
Filip

92TypeR

Okay, sorry for the misunderstanding. I was under the impression the Bosch unit was tunable.

In that case, it may make sense to address the ECU side first. Get the tune down, setup the traction control, and then tackle the engine side.

The cam profiles can be determined based on the driving you want to do. Are you looking for a higher RPM motor or are you just looking to boost the current powerband? If you are in the U.K., there are a few good camshaft manufacturers that can make custom grinds for your application. I know Kent Cams has experience with Hondas. Cat is another good European option.

blueBB4lude

ill have to find the links and the name of the books, but you can modify the intake runner lengths to improve performance at different rpm bands. I built an intake for a Fomula SAE car during my undergrad in mechanical engineering. There is a series of equations to determine runner length and diameter, could maybe look into this

there is also a concept of using the reverberated air from the intake much like sound waves, to bounce it off a closed throttle and then rebound back into the chamber once the throttle is opened again. These calculations are rather complicated though (differential equations and some equations from vibrations) The idea is centered on the Helmholtz equations. (http://www.phys.unsw.edu.au/jw/Helmholtz.html)

This may be too technical, but when we tuned are Formula SAE cars we looked at exhaust, intake manifold, and fuel.

92TypeR

Pretty much all FSAE'ers use Winterbone/Pearson Theory of Engine Manifold Design: Wave Action Methods for Ic Engines as the gospel of manifold tuning.

We used the Winterbone/Pearson models as a base, and still ended up with 300+ dyno runs tuning intake and exhaust before finding the right combination.

FerreiraCompetitions

Filip,

If you dont want to use a Motec because of price, then you'll find that modifing the engine will also be out of your budget. That engine without the restrictor will already make an easy 270-280 hp, so the R&D of getting it to 300+hp will be prohibitive.

Other good Pro level engine managements, are Pectel, Autronics, Gems, Magneti Marelli.

lander

Why use Motec for 4000USD when you can use another ecu system for 1000 USD and you will get the same results? Only because Motec is Motec? That is not for me.

How to make easy 270-280 hp? That is what i am looking for :-)))))

lander

Yeah, bosh ecu is tunable, but you need prehistorical Dos software for it. I think that I have cable, but another ecu system will be better.
For now engine has top torque at 5000 rpm, and top power at 6000 rpm.

I am not in U.K. , I am from Czech Republic, EU.