DOHC 16V B6 or B5 Head with B1 Block?

[forpinks]

I'm from the Philippines, I don't have a Festy but do have a Kia Pride which is basically the same without the Ford badge. The B1, It's like the B3 with 1.1L and a tiny carburetor... First off, I'm keeping my stock engine for the hell of it. I'm sick of people telling to quit on my B1 and get a Mazda B5, B6, B6T, B8, BP, BP.

My question is if it would be possible to modify the B1 engine to have DOHC by using other B-Series heads? Because I've heard and read the the B6 is a bored up B3 and also that the B3 and B1 is almost the same with different strokes from the crank. I just want to do something differently. I want to try and keep the 1.1L displacement and try to get the revs up to 9K from that cast-iron block.

If anyone here has an idea on what to do to modify a B1 engine, please do give me advice...


Thanks!

[htchbck]

I believe the B1 actually has a smaller stroke AND bore. Not but much, but some. It might be possible to get a B6 DOHC head onto a B3 block, but even that is a stretch because of the difference in the bore size, and with the B1 being smaller still, it would be that much harder. Not saying it can't be done, but with the amount of time/engineering/fabrication/money that it would take, the end results might not be worth the effort.

[FestYboy]

get a B3/B6 block and a BJ crank if you're looking to have it rev that high. that'll give you a 71/78mm bore and a 67.5mm stroke. custom pistons shouldn;t be an issue and you can play witht he rod ratio more easly. if I were to do it, i'd use the B6/BJ combo and capri B6d head with Ti valves on intake and SS on exhaust and Ti retainers and beehive springs.

[forpinks]

I have access to really cheap fabrication in machine shops and could find an awful lot of pistons and rods to fit the engine. I guess I should try and ask around if they could make some sort of adapter for the B6 head to fit the B1 block. But I bet that would kill the comp-ratio...

So, if I get a B3 or B6 block running 72mm pistons and 67.5stroke rods topped with a B5 or B6 DOHC head that's PnP'd and a BJ crank that's lightened or even knife edged, how hard do you think it could rev with proper engine management and ignition? Maybe I could even do individual liter bike carbs and MSD ignition. : D

BTW, are the B1, B3, B5/B6 engine blocks pretty much the same? Just thinking since I would change internals anyway, maybe it would be a great idea to just bore out that cast iron block if it turns out to be the same?

Also, about comp-ratios could the engines take about 10:1 or higher compression?

Thanks for the info guys, they already helped me into opening up my mind on doing a hybrid B-Engine project.

[FestYboy]

you could essentially see 11k+ rpm if you use quality parts. the blocks are essentially the same save for oil squirters on some models. the compression should be better than 10.5:1 for what you're trying to do, figure more like 12:1 or more (like building a bike engine) using a hemi head piston.

[forpinks]

I guess I could just keep the B1 block and bore it out to about 72mm. Would installing hemispheric heads interfere with the non-interference design of the "B"? Also, what company makes those hemi head pistons in 72mm bore?

[forpinks]

Is it possible to just rebore the old block? My engine has less than 30K km on it. I guess it could work.

[FestYboy]

no, you can't take a B1/3 block to B6 bore sizes (but you should be able to take it to 72mm). there are several motorcycles that use a 72mm bore and larger. the hemi aspect MAY cause the engine to go from non interferance to interferance depending on the valve clearances in the piston.

[forpinks]

So, how do I get the B1 to have a 70-72mm bore and 67.5mm stroke? Do I still need the BJ crank, or would doing custom pistons and con-rods be sufficient enough?

I guess I also have to make sure I have lots of clearance on the head. Lots of shaving is probably required...

Anyone know a company that makes decently priced built-to-spec custom internals?

I just want to try and hone the B1 enough and make it like a bike-engine.

Thanks for the usable info!

[NicholasJackson]

There are no decently priced custom parts.

[FestYboy]

must have the BJ crank to attain the stroke you're flooking for.

[Rocketman]

you could essentially see 11k+ rpm if you use quality parts. the blocks are essentially the same save for oil squirters on some models. the compression should be better than 10.5:1 for what you're trying to do, figure more like 12:1 or more (like building a bike engine) using a hemi head piston.

Theoretically that might work but what about stuff like the oil pump? Those prove problematic on high power / high RPM B6/BP

[DriverOne]

Theoretically that might work but what about stuff like the oil pump? Those prove problematic on high power / high RPM B6/BP

Would it be possible to add a second oil pump on a clutch?

[Rocketman]

Would it be possible to add a second oil pump on a clutch?

lol, what?? how is that going to keep the stock pump from grenading? why a clutch?

It's possible to go to a dry sump system with an external pump but now you're looking at muchos $$$

[festyfreak39]

i dont know much about the B1 actually this is the first time ive heard about it, but either way its a mazda and can probably be boosted reliably...

what is the head like? what if you add a thicker metal h/g.. run fuel injection and boost the thing?