Neither GR's RE7" (Weber) nor RE5" (Weber) manifolds will fit WITH a filter without hacking a box into the firewall. (but they are great manifolds for HP).
Ditto fitting anything longer.
However if it's an automatic, you can just coax a Ramflo or conical K&N onto the SU with the RE7 manifold as the motor is mounted further forward.

Redline 3005 Weber manifold fits OK with a Ramflo filter, when ported well GR says these flow fine up to ~125HP.
Minispares 1-3/4" manifold + Ramflo fits fine, I also put a 20mm spacer on the manifold to add a bit of induction length. I then port the manifold & spacer a bit. With a K&N filter you may need a shorter spacer here.

Minispares 3-1/2" cast alloy Weber manifold has a height problem, the Weber carb hits on the firewall cutout. As sam_1100 found out.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

he was quite specific - GR manifold for a 1.75 SU can flow better than one of the redlines for a weber. Certain manifolds will fit without firewall modifications, some won't. The longer redline version for a weber needs a weber box or a big dent in the firewall. The shorter 3005 should fit OK but may not flow as well as the longer two manifolds he is talking about. He mentioned nothing about twins. It was all about single carb applications.

There is some good information available here, if you READ the posts.

EDIT - must have spent too much time re-reading my post. the Doc beat me by three minutes

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Unfortunately if you want to have a 45mm sidedraft without hacking firewall you haven't got much choice. A 3.5mm Redline/Warneford manifold with an offset Lynx Ramflo filter will just fit. You'll need to machine the manifold so that kicks up it is a few degrees however. You may need a very small amount of hammering to make the filter clear the corner of the speedo hole in a round nose. I think clubbies fit better.

The problem is to make Redline manifolds work they need to be ported properly and then the other end also needs some sort of ram tube or stub stack. Generally there is a lot of work involved to get it to produce lots of power.

With HIF44 I have seen the GR manifold fit on a small bore in a clubby without a filter... No idea if it will fit with a filter but I am sure some sort of offset Ramflo will fit? as 1310/71 says the SU manifold flows better than the redlines unless there is MUCH work done to the Redline.

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Lillee - 1969 Morris Mini K

If you are interested in the specifics, on my build I tried the following setups: (working from memory here so bare with me)


Dellorto 45 on a very well ported (walls were so thin!!!) redline manifold, Dr.Mini special tuning stub stacks no filter: approx 114bhp

Dellorto 45 on same redline with Ramflo filter: not very good, about 107bhp before the ramflo caught fire and nearly destroyed the workshop (no exaggeration)

Dellorto 45 on RE7 manifold with proper 1.5inch ram tube trumpets, no filter: 119bhp, 100ft/lbs

Weber 45 on RE7 manifold, DIY ram tubes, no filter: 117bhp But I felt this also had the wrong jets in it, also smaller chokes than the Dellorto

HIF44 on GR's SU manifold no filter, stock factory stub stack: 118bhp But i feel this had the wrong needle and I am more than sure it can do more. Also had very good torque curve from memory, full torque much earlier than sidedrafts. Actually it worked so well that about a year later I organised to have a setup replace my Dellorto but in the end, I stuck with Dellorto (glad I did!)




So as you can see there isn't much in it at all between the Dellorto/Weber or SU. In fact I am sure they can achieve all the same HP if all set up correctly.

Now in terms of filters: Firstly I have a weber box welded into my car so much more room than most people. Once engine was in the car I played around with several setups. Ramflo with Unifilter foam and with or without oil, the car ran very rich. There was definitely restriction there, but for many there is no choice. It can be made to work...

I then tried a K&N very short side entry oval filter, and this was worst than the Ramflo. The backplate basically extremely restrictive and since the filter was only 2.5 inches tall there wasn't much flow. I feel the 3 or 4 inch tall K&N's will be best but then the setup will be so long that the filter would be inside the cabin above your gearstick!

Unifilter ramtube socks, which just go over the ramtube and held on with zip ties. Works well, gets dirty fast (good thing!) and very low restriction. BUT very very hard to clean and maintain. Cut zip ties, wash socks, put them back on, took ages and ages.

Finally I settled on PiperCross filter. Looks like the one in the second picture http://www.pipercross.net/competition/p ... _socks.asp They slip onto both trumpets and stay on, weigh nothing, and best of all very very low restriction. This may actually work for many people even without a firewall mods, the foam just deforms and sits on the firewall?


Hope that helps!

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Lillee - 1969 Morris Mini K

A few pics of the RE9 manifold with both an HS6 and an HIF44 carby.
Not much room for a filter, but the space varies a bit from car to car.

HS6 carby-





HIF44 carby (note carby is sitting against the firewall and the manifold, it's about 1/2" too high to bolt on. Angling the manifold up a bit at the head flange helps this, but go too much and the bonnet won't shut.
Really you need to take to the firewall with a VBFH...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Air cleraner? who cares. Have a gander at the jet position on the HS6? Almost touching the firewall. Engine movement and guess what will happen? Not to mention you can't use a choke.
I run a GR su manifold on my ex-matic. Despite being kinked upwards away from the bulkhead the jet would hit. Bulkhead has been slightly modified luckily for me as it gave a (slight) cure but I can't use the choke.
My HS6 uses the MED/ITG filter/stub stack kit. It fits but not well enough for my liking. Having said that my mini goes like a cut snake.