Page 9 of 19

Re: 1965 Seven S2

PostPosted: Tue May 26, 2020 1:20 pm
by SENC
I'll grab some measurements for you after work, Kyle. Unfortunately I don't have any pictures on my phone from quite the right angle to help you, but the one below gives a few potential reference points for you. I would agree the angle on yours does look high.

IMG_20200526_091443.jpg and


Thanks Alan. I sent a note to the folks at Scorcher and they very promptly sent a note with part numbers for the points.

Re: 1965 Seven S2

PostPosted: Tue May 26, 2020 3:39 pm
by disquek
I just spoke to Xtra Special Sevens (wonderful folks) and they have a copy of a stock manifold. They tell me that the angle on theirs is 12-15 deg. Mine is closer to 15.

I'm very curious what yours is.

-Kyle

Link: http://www.xtraspecialsevens.co.uk/odds.html

Re: 1965 Seven S2

PostPosted: Tue May 26, 2020 7:13 pm
by jk952
Late to the party, but below is a picture that may be useful from a Cortina book.
Has two marks on the pulley; and shows timing relative to positions on the alum casting that looks similar to yours. Not sure if same.

2A659939-4481-421E-8F62-31C1D68970CE.jpeg and


Maybe a better pict. this time..

Re: 1965 Seven S2

PostPosted: Tue May 26, 2020 9:13 pm
by SENC
disquek wrote:I just spoke to Xtra Special Sevens (wonderful folks) and they have a copy of a stock manifold. They tell me that the angle on theirs is 12-15 deg. Mine is closer to 15.

I'm very curious what yours is.

-Kyle

Link: http://www.xtraspecialsevens.co.uk/odds.html


Not a lot of great places to place levels and take measurements, but I came up with 4-6 degrees every way I tried. Used a small bubble level on the heat shield below the carbs and also above the carbs with a spacer on the back of the carb top to replicate the choke cable on the front. Also took some measurements from a big level and calculated the tangent of the rise/run. Here are a few pictures that may be useful.

IMG_20200526_171136.jpg and


20200526_165703.jpg and


IMG_20200526_155754.jpg and


IMG_20200526_160013.jpg and

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 7:08 am
by vstibbard
thanks for the pictures and measurements Henry, the original setup on yours look scarily like mine, rising straight up from caliper to for my safety a little close to the rim before it turns

V

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 8:09 am
by vstibbard
Mine has stock inlet manifold and new engine mounts fitted sits at essentially same height from chassis as Henry's.

Cheers

Vaughan

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 10:45 am
by SENC
I looked for it last night unsuccessfully, but have read somewhere recently that max incline for a DCOE should be 5 degrees - that any more causes issues with fuel leaking from the bowl and down the throat.

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 3:04 pm
by disquek
Thank you for the pictures and measurements! That's a big help!!

I agree and I've also read that 5 deg is the maximum recommended incline for a DCOE. It seems that Colin didn't read the same thing we did! lol I think with 4" wheels and bias tires, it wasn't an issue. This car has 7" wheels and 10.5" wide slick tires.

The car is dry sumped and I wonder if when that was done, that the motor was lowered also. This might require a manifold that gets the air horns above the upper frame rail. Like the 15 deg inclined ones. I'd like to see if there is a more S shaped manifold out there that will raise the carbs up, but also keep them close to level.

A friend recommended the Burton's manifolds. I will look into them. They publish dimensions of length and rise for their manifolds. Very nice!

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 3:09 pm
by SENC
jk952 wrote:Late to the party, but below is a picture that may be useful from a Cortina book.
Has two marks on the pulley; and shows timing relative to positions on the alum casting that looks similar to yours. Not sure if same.

2A659939-4481-421E-8F62-31C1D68970CE.jpeg


Maybe a better pict. this time..


Thanks, that is useful - at a minimum it gives us the increments at the markings.

Re: 1965 Seven S2

PostPosted: Wed May 27, 2020 10:03 pm
by SENC
disquek wrote:Thank you for the pictures and measurements! That's a big help!!

I agree and I've also read that 5 deg is the maximum recommended incline for a DCOE. It seems that Colin didn't read the same thing we did! lol I think with 4" wheels and bias tires, it wasn't an issue. This car has 7" wheels and 10.5" wide slick tires.

The car is dry sumped and I wonder if when that was done, that the motor was lowered also. This might require a manifold that gets the air horns above the upper frame rail. Like the 15 deg inclined ones. I'd like to see if there is a more S shaped manifold out there that will raise the carbs up, but also keep them close to level.

A friend recommended the Burton's manifolds. I will look into them. They publish dimensions of length and rise for their manifolds. Very nice!


Are your motor mounts standard?

I looked at the mounts on xtraspecialsevens (agree, good folks and very knowledgeable). They look identical to mine, and I can't see how they'd put the carbs on a slope greater than a few degrees. I can see the slope of the throats being 10-15 degrees, but the two faces don't look far from parallel, like mine.

Re: 1965 Seven S2

PostPosted: Fri May 29, 2020 11:35 pm
by vstibbard
You mentioned that it has a dry sump, in period some dry sump engines were tilted to lower the engine and allow the nose/bonnet and scuttle to be lowered to reduce frontal area, this may explain the higher inlet manifold angle when mounted upright.

What block are you using is it a 711M which is higher overall than a standard 116/120E block?

Re: 1965 Seven S2

PostPosted: Mon Jun 01, 2020 1:33 am
by SENC
Made some good progress today, thanks to some help from Keith Franck and others.

Surprisingly found a primary contributor to my afterfire/popping were the replacement idle mix adjustment screws that came with my rebuild kit. The newer ones are more narrowly tapered than the older, blunter screws - and it seems they were letting in a good bit of air. Going back to the old ones almost completely eliminated the afterfire.

Also tried Keith's non-frothing emulsion tube replacements - they had a huge impact on lowering the transition point at which the main jets kick in and went a long way towards eliminating the sub-3k rpm flat spot. I still have some tweaking to do but quite happy.

Re: 1965 Seven S2

PostPosted: Wed Jun 03, 2020 5:52 am
by vstibbard
Great news, which e tubes did you fit?

V

Re: 1965 Seven S2

PostPosted: Wed Jun 03, 2020 11:27 am
by SENC
His newest NF (non-frothing) tubes, with which he seems well pleased and my initial experience is certainly very positive. I started out with the 115 main jets standard on our webers and dropped the air jets down from 180 to 120 based on his initial guidance, and I'd say that is pretty close if not right. I plan to test jets to either side of those as well as idle jets to see what tweaking makes it better, and need to go back to ignition and timing again, too, now.

Re: 1965 Seven S2

PostPosted: Wed Jun 03, 2020 11:05 pm
by SENC
alanr wrote:The original engine breather fitment on the non-crossflow engine was the metal breather that you have in the block with a 'u' rubber tube over it attached to a metal outlet tube fixed to one of the bell housing bolts and pointing free to air.
This is the only photo I can find on the web of the tube and 'u' rubber piece:-
The attachment breather tube.jpg is no longer available


Alan.


IMG_20200603_190231.jpg and