RS Motorsport :: Classic Speed Restored

Hi,

Looking at the RX7 box for my YB headed pinto block(Going for 240HP). Sent an email today but being the holidays and all not expecting an answer for a bit.
Would one of these suit the pinto behind an alloy bell housing? Input shaft OD and splines the same?
What about weight. How much heavier would this box be compared to a 4spd Rocket box with alloy bell housing/maincase.
My engine is mid mounted so total length is important. Whats the length of the box to the shift housing?

Any help appreciated

Steve

Hi Paul, thanks for the reply.

Roger got back to me via email the next day. He's confirmed the input spline is the same and offered me an alloy bellhousing to suit a pinto block.
However after a careful look at the ratios in the mazda box i may have to go 4spd straight cut gearset. At Collingrove I'm pretty much using 2nd gear @1.99:1 to get off the line.(1st only being useful for warm-up tires).
Mazda box has a 2.02:1 ratio 2nd and 1st is 3.48:1. Unless I can get a better 1st gear ratio its probably better to choose a gearset with the right ratios.

Whats the chances of being able to swap cogs between boxes. A 13B non turbo box has a 2.22 ratio 2nd gear....mix and match?

Other issue is total length. I can see how you can move the shifter on the Mazda box forward but my tailshaft length would be almost uni to uni with the extra length of the mazda unit. I'll be checking Roger's measurements out against my current box today so then we'll see.

Regards

Hi all,

Yes,I'm still doing Duratec into Escort conversion bits, and my e mail address has changed to:
jrprmc1@bigpond.com. or contact me on 0408 804 795.

Regards,
Roger.

Hi all,
Just an up-date: I have added a new horizontal filter/oil cooler adaptor (for engines with internal oil pump) to fit both Escorts and Clubmans alike, plus competition (Std) main and big-end bearing shells to my full list of conversion parts.
I also have a new email address: durescort@gmail.com or phone 0408804795.
Cheers,
Roger.

Hi Again all,
Another up-date:
There used to be a problem sourcing a 2 stage scavenge only dry-sump pump for my dry-sump, but no more.
Peterson in US do them in their new all alloy light-weight R4 range. They are a highly efficient Rootes 'twisted lobe' style originally designed for the modern Corvettes (I believe) so have tons of capacity and are far cheaper than any other dry-sump pumps around.
I can supply them along with the necessary mounting brackets and special hoses to clear the steering and engine mounts for LH and RH mounting.
Pls. contact me on durescort@gmail.com for pics. and more details.
Regards,
Roger.

Roger how come you don't run their 3 stage and run the pressure through the Peterson as well

Hi Danny,
A number of reasons to separate the scavenge from the pressure systems:
1) You can change the amount of scavenge you want by changing pulley ratios without upsetting your pressure circuit volume (which is usually matched perfectly to the engine demand and doesn't need to be messed around with)
2) Any increase in pressure pump volume caused by changing pump speed is wasted power, which translates to relief valve working overtime and increased oil temp.
3) Plumbing is simpler and no high pressure hoses to leak or burst.
4) Scavenge-only belt loads are about a quarter of loads for a scavenge + pressure type pump.
5) Scavenge-only pump is much cheaper/more compact than the same with a pressure stage added on; why scrap a perfectly good OE internal pressure pump with its relief valve, to then pay extra to put it on the outside with the additional reliability risks and complications that introduces!
In the case of the Duratec motor, it's OE pump has surplus capacity and is enough to cover the additional demands of racing. I have never even marked a bearing let alone failed one, and not seen any sign of lack of lubrication in the 5 years I raced mine (until I wrote it off) so I follow the Kiss principle and "if it ain't broke, don't f*** with it" ! LOL
Regards,
Roger.

Just for other's info, I contacted Roger Carroll this week on durescort@gmail.com to see if he is still doing Duratec parts. He replied and certainly is.

Due to regulation changes I think I am having to build up a 2.4L Duratec so his parts will be useful.

If anybody has any information on a Duratec build (using 2.5 block, 2.0/2.3 head and 2.3 crank) feel free to share. At this stage I am leaning towards +2mm inlets valves, +1mm exhaust valves. Not sure on what porting the head requires (no published info can be found yet). Not sure on what rods, pistons or cams.