Baja 5B SS - Over the years - help me choose an engine...

[horatio]

So, here's my Baja over the years. It was 15 years old in July 2024. 

 

 

So now, I have to choose a potent small block engine.

 

I'm leaning towards the SCZ 29.5, but possibly would consider the Taylor 35 Reed V2. It's near enough twice the price of the SCZ, but I'm open minded. Which should I choose?

 

The original CY 26cc Fuelie is running well on stock 17/57 gearing:

 

 

What might I expect with the reed engines?

[horatio]

 

So, engines. So much choice, so much hype!

 

My humble 26cc CY Fuelie engine is rated at a mere 2.7 HP @ 13700 rpm. 

And 0.165KG-m @ 10500 rpm.

 

The SCZ 29.5cc reed engines claim 9hp @ 20000 rpm. 

 

And the Taylor 35 Reed V2 claims a walloping 9.5 hp.

 

But what's real and what's just pure fantasy? It's not like the majority of us have a Dyno to check our real world figures.

 

I refer to videos of all these crazy engines, hauling ass - but sounding fluffy and a bit off - pulling around hugely modified rigs with lots of alloy, likely weighing twice as much as my rig. They look awesome, but they're not seemingly built for acceleration, response or top speed. They're designed to plow fields and create huge roost trails! 😝😎

 

I'm wanting to keep mine light.

 

My replacement engine ideally will weigh no more than 2kg.

 

That means that the tempting, lower cost option would be the SCZ 29.5 which I can obtain for about £300, direct from China, including shipping.

 

The Taylor 35 cc Reed Case V2 is supposed to yield more power, despite revving slightly less - but offers more torque. However, it's £669. 

 

Please - if people here have had contact with either of these engines, spare a moment and discuss the virtues of each here.

 

I'm yet to be convinced that the Taylor would be the right choice, but I'm 100% open to it - if people explain to me why the V2 is worth the extra £369. 

 

 

Edited August 20 by horatio

[Dun2504]

I put an scz in my very modified 30 Degrees North buggy , and it is great.

You need a proper tuned pipe to make it sing though , I would go with a side pipe . I have just purchased a Taylor pipe to go on my Baja , which I am fitting a chinese 32 reed case motor to , they are even cheaper than the SCZ ,but not as nicely built.

 

[horatio]

5 hours ago, Dun2504 said:

I put an scz in my very modified 30 Degrees North buggy , and it is great.

You need a proper tuned pipe to make it sing though , I would go with a side pipe . I have just purchased a Taylor pipe to go on my Baja , which I am fitting a chinese 32 reed case motor to , they are even cheaper than the SCZ ,but not as nicely built.

 

I'm hoping to use the curly SS pipe. I'm assuming it would fit?

 

I'm not a fan of giant pipes - I want my Baja to look like it does now. In fairness, my curly silver pipe performs really well - it's just extremely loud.

 

What carb are you using?

[Dun2504]

Hi.

I used a bearing mod Walbro WT 1242, But then went to a Walbro WT1191 as it has a choke lever . I would strongly urge you to get a decent pipe as the little curly one will strangle the engine at high revs and reduce the torque all the way through .

[Dun2504]

I doubt your pipe would fit unless you made a copper gasket blank for the port , as the exhaust port is quite big . I had to open up the flange on my VRC pipe and use a copper gasket to make it fit.

But it is worth the effort , as it has loads of power everywhere .

You may want to look at the standard gearing too , I am up 2 teeth on the pinion on my 30 Degrees North buggy and it is scary on full throttle.

[horatio]

2 hours ago, Dun2504 said:

Hi.

I used a bearing mod Walbro WT 1242, But then went to a Walbro WT1191 as it has a choke lever . I would strongly urge you to get a decent pipe as the little curly one will strangle the engine at high revs and reduce the torque all the way through .

 

Great advice, thank you. I know people often say that the choke is optional, but it does make starting easier.

 

1 hour ago, Dun2504 said:

I doubt your pipe would fit unless you made a copper gasket blank for the port , as the exhaust port is quite big . I had to open up the flange on my VRC pipe and use a copper gasket to make it fit.

But it is worth the effort , as it has loads of power everywhere .

You may want to look at the standard gearing too , I am up 2 teeth on the pinion on my 30 Degrees North buggy and it is scary on full throttle.

 

Thanks for the heads-up. I'm happy to do some fettling, possibly working on a brand new one to make good.

 

The SS pipe made good power on the CY 26 and I've been waiting 15 years for someone to show me (in black and white) how all these mahoosive pipes gain them HP on a Dyno, or with MPH on a GPS.

 

The closest I've got to this is someone telling me that they had an ESP top end kit on their G290 and Jetpro V3 exhaust which hit close to 60mph, although I see no actual GPS numbers.

 

That all being said, I don't necessarily want to reduce the performance of an SCZ or OBR signature series V2 Reed engine, just because I like the curly SS pipe.

 

But it does have a great form factor and that matters when your rig is light and sexy! 🤣👍

[Dun2504]

Not the right shape for a true expansion chamber sadly.

I am in the process of fitting a nice cheap £250 reed case FLMF motor to my baja . Motor looks decent quality , but I stripped it and mildly smoothed the ports in cylinder and case : fitted a new piston with boost ports . but none of the above is vital. fitting a nice Taylor side pipe to go with it.

I expect loads more power then the rovan 36 it has in at the moment.

[horatio]

On 28/08/2024 at 00:12, Dun2504 said:

Not the right shape for a true expansion chamber sadly.

I am in the process of fitting a nice cheap £250 reed case FLMF motor to my baja . Motor looks decent quality , but I stripped it and mildly smoothed the ports in cylinder and case : fitted a new piston with boost ports . but none of the above is vital. fitting a nice Taylor side pipe to go with it.

I expect loads more power then the rovan 36 it has in at the moment.

Just working out my Baja 5B Gearing and rollout. Having hit 49 mph, working back from that figure - 17/57 gearing, on 170mm tyres - my rollout is 70.28mm/rev. 

 

This means my 26cc Fuelie Engine is revving at 18700rpm! That's on the silver curly pipe.

 

Will the reed case, modified engines hit higher rpms with greater torque - using the same exhaust?

 

The curly exhaust has a reasonable size expansion chamber on it - but the header is short.

 

I feel this needs to be explored. It could be that the curly SS pipe is not ideal at boosting top end power, but 18700rpms is decent considering it's 15 year age and that it's only rated for 22000rpms with no load.

 

I'm looking at OBR full mod G340RC Reed V2 motors. Zenoah G320/340 engines make good power as standard, so I'm guessing OBR modded versions have to have decent output. But how would it compare to an SCZ 29.5? 🤔

[Dun2504]

The SCZ is a copy of the BZM engine which was very good : Materials and fit of the SCZ is very good and it is half the price of the OBR .

I would buy a Taylor over an OBR anyhow.

Try with the curly pipe and experiment with a proper tuned side pipe , But I think it will mage a big difference.

 

[horatio]

2 hours ago, Dun2504 said:

The SCZ is a copy of the BZM engine which was very good : Materials and fit of the SCZ is very good and it is half the price of the OBR .

I would buy a Taylor over an OBR anyhow.

Try with the curly pipe and experiment with a proper tuned side pipe , But I think it will mage a big difference.

 

How is the Taylor over the OBR? 🤔 It seems very expensive.

 

OBR UK (the branch in Ireland) haven't been terribly helpful. I asked: what sort of RPMs would I expect with the full mod.

 

What I had back was where are you based, what gearing they recommended. But no answer to my question. Followed by 'keep what you got' - toys out of pram. 🤣🙄

 

 

Clearly some communication issues going on there. Not very business like at all.

 

Unlike OBR USA:

 

 

They gave a figure of 18-19k RPMs and were quick to offer the up sell, seeing as I had clearly indicated that I was looking for RPMs.  This aspect seemed entirely lost on OBR UK. 🤔

 

 

Anyhow, let's see what happens. I love TR stuff, so the V2 Billet Reed Case engines appeal to me, as it's in keeping with my TR clutch system and 'Quick Diff' transmission case.

 

Taylor engines look and sound interesting, but I've no real way of knowing how they stack up against more established ESP and OZR offerings.

[Dun2504]

I would go Taylor , ESP AND OBR  are just reworked Zenoah to a certain extent , where Taylor engines are designed from scratch and have a very good reputation .

Taylor are at least as well established as the other brands , and have plenty of race experience behind them .

I am finding that even with my 32cc Chinese reed case engine , it is way too much power for 2 wheel drive and is very interesting to drive.

The SCZ in my modified 30 DNB is much more stable and easy to drive.