Escort Sigma 1600 Race Car

[Roadsport]

Re: Escort Sigma 1600 Race Car

+ / - one inch in lenght of each other? Really!?

I've desparetly aimed for 5mm difference. I've measured them all to be in 1mm of each other but since theres no sure way of measuring the pipes I guess theyr all within 5mm of each other.
I allready had the no 1 pipe put together but it was 15mm shorter than the others so back to the draving board
But this time I allowed my self to leave gaps in the seams to be filled later with tig. The welder said no problem that he could fill 2mm gaps with no problem but I left him one 5mm one just to make him earn his fee

[Tristan]

Re: Escort Sigma 1600 Race Car

hahaha good stuff!

[RWD fords rule]

Re: Escort Sigma 1600 Race Car

[QUOTE=Roadsport;1762740]+ / - one inch in lenght of each other? Really!?

Absolutely, personally I would aim for + or - 1/2" between all of the pipes as a bunch (1" being the largest possible difference between a short and long pipe)
I would be extremely surprised if there was a noticeable difference in performance on track or on a dyno compared to a manifold with equal length primaries.

Ideally you want a straight section of pipe about 2 or 3" long coming out of the head and then weld the pipes to them, but that is not really practical in an escort engine bay.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Yes I noticed. My no 1 and 2 pipes start curving right at the flange not ideal but it was the only way to make them fit. I intended to put in the straights as I did on the 3 and 4 pipes but the bends I ended up with prevented it. To get the 2" straight would mean a whole new desing to the manifold and for now I've had it up to here with manifolds .
I got it finished today though
Even did a cool lighter test on the scavange effect. It was there.
I even had time to remove the rear axle for the True Trac installation.

Pics wil follow.

[Roadsport]

Re: Escort Sigma 1600 Race Car

Hope you don't mind a few (too many) pics. It's just that I'm quite chuffed I got this done. I keep waiting for something to turn up and bite me in the ass but so far it all seems good.







The collector sits neatly between the chassis rail and the engine block. Tha clutch cable will propably need some heat sleeve.



Evo I and II. Dyno will tell if the evolution has done any good other than raising the collector.

[Roadsport]

Re: Escort Sigma 1600 Race Car

The video of the lighter test.

[TepiTheFinn]

Re: Escort Sigma 1600 Race Car

I'll guess only thing you proof with this test is buy yourself a Zippo

[Roadsport]

Re: Escort Sigma 1600 Race Car

Really? Well that if not anything else. That Colt did have serious misfire.

[Tristan]

Re: Escort Sigma 1600 Race Car

just a question... I thought that manifolds usually had the pipes increase in diameter/section after the flange , to prevent gas reversion?

[Roger Miller]

Re: Escort Sigma 1600 Race Car

just a question... I thought that manifolds usually had the pipes increase in diameter/section after the flange , to prevent gas reversion?

It has, have a look at the piddly little holes with the lighter.



And yeah that collector is certainly gonna create some scavenge.....................but how much restriction to top end.

A 421 style would have made more top end and have a fatter mid-range.

[Graham]

Re: Escort Sigma 1600 Race Car

It has, have a look at the piddly little holes with the lighter.



And yeah that collector is certainly gonna create some scavenge.....................but how much restriction to top end.

A 421 style would have made more top end and have a fatter mid-range.

you've built and tested manifolds on this engine then??????????????????

[Roadsport]

Re: Escort Sigma 1600 Race Car

just a question... I thought that manifolds usually had the pipes increase in diameter/section after the flange , to prevent gas reversion?

Hi Tristan. I really haven't even thought about the reversion.
This one has the same diameter pipe from tha flange to the collector. The hole in the flange however is smaller than the inner dia of the pipe. Though the hole in the flange may need to be grind to mach the port in the evo head 'cause it has larger ports. Even then the flange has propably as wide hole as the pipe but not as high since flange is oval and and hole is round. Or if the ports come back huge I may need to flatten the pipes oval too.

I had small stubs of smaller pipe inside a bigger ones in the previous manifold and they just didn't stop not bothering me. So I wanted to leave them out of this one. And 'cause of the bigger ports I propably could not fit them anyway.

As for the gas reversion, tbh I really don't know
This beeing a shorter system I hope it'll just blow the gasses right past the collector and never see them reversing

[Roadsport]

Re: Escort Sigma 1600 Race Car

It has, have a look at the piddly little holes with the lighter.



And yeah that collector is certainly gonna create some scavenge.....................but how much restriction to top end.

A 421 style would have made more top end and have a fatter mid-range.

I don't really know what to say to that Roger. But I've heard something like that before. Other than 421 making more top end power?
I thought it is 4-1 ultimately making more power but causin a dimp in the torque somewhere between 3500 to 4500 rpms. Which is no problem since this engine will not bee seeing those revs after the start. And they can be flatten by a different lenghts of ram pipes.
But this manifold is thought out to meet my plans and it really should not restrict at the top end. That's tested on other engines.
But when this one is tested, there will be a 421 in the future. Just to see if its all worth the hype. And after all, one can't be sure untill it is tested.
Why would you say it could restrict the top end?

[Roadsport]

Re: Escort Sigma 1600 Race Car

you've built and tested manifolds on this engine then??????????????????

There's the problem. No one has. There are these aftermarket of the shelf items available for the FWD Fiesta and some kits for the Caterhams but nothing for the Escort obviously.

[Graham]

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.