Escort Sigma 1600 Race Car

[Roadsport]

Re: Escort Sigma 1600 Race Car

as you still have your old manifold something worth trying would be to make it some secondaries, so it can be used as a 4,2,1 i've heard good reports on k series engines that had 421s with very long primaries and shortish secondaries.

Now thats a great idea!!! I´ll give both of these a go on the rollers and the weaker manifold could easily be modified to 4-2-1.
Thanks again.

[RWD fords rule]

Re: Escort Sigma 1600 Race Car

I wouldn't worry about the reversion as the 1.625" primary you are using is just about perfect for the bhp levels you are aiming for, you would need to use a 3 or 4" straight length of 1.875" pipe with a 1" anti reversion stub and taper the end of the pipe down to match the 1.625" pipe, but that's never going to fit in an escort engine bay without some seriously strange looking bends and running the collector out at the front of the engine.

Have you thought about tuning the main pipe length? It is said to be more important (having more effect on the power curve) than the primary pipe length.
Making up a main pipe to run down the side of your car for rolling road testing using a simple slider system to adjust the main pipe length would be time very well spent in my opinion, I more than likely will be doing this at some point, then you can see the direct power difference, get the best length for your engine and then make up your exhaust system to match

[Roadsport]

Re: Escort Sigma 1600 Race Car

Main pipe? Not sure what you mean by that? My system is 3" straight pipe to the rear muffler. But I have given a lot of thought to what we talked earlier.

[RWD fords rule]

Re: Escort Sigma 1600 Race Car

Yes I mean the 3" pipe

[Roadsport]

Re: Escort Sigma 1600 Race Car

Really? The lenght of the exhaust pipe has that big effect on the power? I had no idea. Oh man when it comes to exhaust systems there's a whole world out there.

[Tristan]

Re: Escort Sigma 1600 Race Car

as you still have your old manifold something worth trying would be to make it some secondaries, so it can be used as a 4,2,1 i've heard good reports on k series engines that had 421s with very long primaries and shortish secondaries.

Thats the way the Miltek Evo 2 mani's for these engines are done , they claim 10bhp... they must have changed for some good reason.

Really? The lenght of the exhaust pipe has that big effect on the power? I had no idea. Oh man when it comes to exhaust systems there's a whole world out there.

ab-so-freaking-lutely! Aerodynamics , sound waves , thermodynamics , pulsing , scavenging , engineering compromises... it's a minefield!

[Roadsport]

Re: Escort Sigma 1600 Race Car

Could they really have 800mm long primaries like my first manifold has? any idea on the secondaries?

[Tristan]

Re: Escort Sigma 1600 Race Car

I'll measure up in the next couple of days for you. The secondaries are really , really short . IIRC Jason33 got his extended , to broaden the torque band.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Ok. Thanks Tristan. By the looks of them I'd guess they are quite a bit shorter than 800mm.

[jason33]

Re: Escort Sigma 1600 Race Car

I'll measure up in the next couple of days for you. The secondaries are really , really short . IIRC Jason33 got his extended , to broaden the torque band.

The secondaries were extended by about 10 inches on my 1400 Tristian.

[Tristan]

Re: Escort Sigma 1600 Race Car

did it feel much nicer to drive Jason , after doing that? After what you tol me , I was considering it for the Ka.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Got the bottom end back today from the machine shop. Now re ballanced for the new flywheel.
Hopefully I can take the time this weekend to build it up.

Also got the new LSD today
It has some bits for the regular C clip axle but since mine is modified for the 9 inch housing ends I will leave them out. I see no use for them.




And while I had the mock up engine in place I fitted the brackets and covers to see how they fit. Funny enough no issues there...knock on wood.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Can anyone recommend a good quality SAE 90 mineral based gear oil with no LSD friction addittives?

Was thinkiong of getting some from Fords but I belive the Ford hypoid oil has friction additives in it since its used in the Transit and Ranger rear ends .

[Roadsport]

Re: Escort Sigma 1600 Race Car

Some bling. The water pump pulley is finished and fresh from the lathe.
Mui bien.
And its even lighter than the original item

[Roger Miller]

Re: Escort Sigma 1600 Race Car

Got the bottom end back today from the machine shop. Now re ballanced for the new flywheel.
Hopefully I can take the time this weekend to build it up.

Also got the new LSD today
It has some bits for the regular C clip axle but since mine is modified for the 9 inch housing ends I will leave them out. I see no use for them.

This is the diff to have, currently.

http://www.turbosport.co.uk/showthread.php?161075-titan-and-tran-x-lsd-bulk-buy&p=1750040#post1750040