Tb'd 1.6 8v Tu Working Nicely

[Sandy 191]

I've been frustrated for a while by the shape of the DCOE/TB inlet manifolds avaiable for the 8v TU, as I often feel they mask the potential of the engine, either by the poor shape or the angle at which the Carbs/TB's are fitted limiting inlet length severely, particularly in the 106. I've previously designed a couple long runner manifolds for the 205 TU fitment (with the bigger valve late head), which improved the shape by lengthening the transition from the TB's spacing down to the ports. The 106 has been more of a challenge though, because space is much more limited. The only way to get decent length was to curve the runners gently so the overall tracts from valve to trumpet are 340-360mm long (depending on the trumpets). With the Chadil manifold for example, about 290mm is the practical maximum before the brake bar obstructs.

I've fitted this manifold onto my friends 106 Rallye, which already had an S1 inlet manifold and had been remapped with a QEP head (standard valves), devil 4-2-1 manifold and 277/280 cat cam. After i'd overcome some teething issues with running two sets of injectors, we were very pleased with the end result. It feels stronger everywhere and pulls much cleaner than it did before. We didn't have it in the rollers directly before the switch to TB's, so we don't have a direct comparison, but we were able to compare it to a friend of mines (very healthy/quick) 106 GTi, which is one of those that seems unreasonably quick for the alleged power! Here's the curves:

 

http://noboost.com/temp/sandy/Power%20grap...20vs%20Pete.JPG

 

And having driven them back to back last night, that's exactly how they feel.

 

Here's the set up:

 

http://noboost.com/temp/sandy/PR1.jpg

http://noboost.com/temp/sandy/PR2.jpg

 

It sounds fantastic too, one of the best sounding 4 cylinders i've heard, genuinely! This video doesn't really capture the full drama, but it's a bit of fun anyway:

Right click save as

 

To say i'm chuft with how it's turned out would be an understatement!

[smckeown 1]

sweet

[Rippthrough 98]

Nice work!

Luckily with the 306 I have a bit more room for a decent size/shape inlet, so hopefully my switch to tb's will be just as sucessful.

-Phillip

[Sandy 191]

Definately, the 306 has alot more space.

[Rippthrough 98]

Definately, the 306 has alot more space.

 

Through the bulkhead, leave the glovebox open...stick the bodies out the passenger window....

 

Did you have the manifold made up to your specs or did you make it yourself?

And is it me or does it taper towards the ports too?

[welshpug 1,657]

how about this kinda arrangement?

[Sandy 191]

Through the bulkhead, leave the glovebox open...stick the bodies out the passenger window....

 

Did you have the manifold made up to your specs or did you make it yourself?

And is it me or does it taper towards the ports too?

I designed it and Colin Satchell (my fabricating friend) made it. Yes it is tapered from 45mm bodies to 40mm ports at the outer end, the ports taper slightly more after. Getting the bends and angles to my satisfaction was tricky as hell. It was alot of work to get how I wanted it.

[Sandy 191]

Those above are the 106 Kit Car ones, impossible to get now sadly and very expensive when they were available, only one injector location two looking at those!

[Rippthrough 98]

I designed it and Colin Satchell (my fabricating friend) made it. Yes it is tapered from 45mm bodies to 40mm ports at the outer end, the ports taper slightly more after. Getting the bends and angles to my satisfaction was tricky as hell. It was alot of work to get how I wanted it.

 

 

Tell, me about it, did you bend first then open them up, or taper first then bend?

 

Last time I tried something similar I tapered them first then packed them and bent them, and ended up getting a bulge on the outmost curve and 1/3rd of the way down.

[Sandy 191]

Opened up one end a bit, bent, welded then hand finished.

[Rippthrough 98]

Opened up one end a bit, bent, welded then hand finished.

 

 

Hmm, might just be my welding then

 

-Phillip

[Sandy 191]

It's probably better than mine! Fortunately the guy that TIGs for Colin is incredibly good.

[Rippthrough 98]

It's probably better than mine! Fortunately the guy that TIGs for Colin is incredibly good.

 

Nah I've only just started, I can't even set the MIG up right without having 1/2 an hour before welding....

 

Oxy-acetalyne is another matter though, god I love that stuff.

 

I wouldn't mind a copy of your CAD stuff or blueprints if you don't mind making them open to the rest of us?

 

-Phillip

Edited November 4, 2006 by Rippthrough

[Sandy 191]

I wish the design process was that posh, we made a jig.

[Rippthrough 98]

I wish the design process was that posh, we made a jig.

 

 

No scribbled beer-mat calculations then?

 

I've got a PTCprodesktop if you want something that posh, pm me. *OF course this is a legitimate version of which I shall transfer ownership* ahem.

Edited November 4, 2006 by Rippthrough

[Sandy 191]

That's very kind and when I really should learn how to CAD things! Fortunately Colin usually comprehends my descriptions well and empathises with what i'm trying to achieve.

[Rippthrough 98]

Well, after running up a few design's inspired by your solution, I just realised they're all scrap, because my strut brace will be in the way - doh!

 

Look like aiming at the bulkhead after all.

[Sandy 191]

Bugger!

[Rippthrough 98]

Bugger!

 

The air was blue when it clicked!

 

Just thinking about going downwards instead....

 

-Phillip

[GazRallye 0]

What difference is the between running tbs with short/long trumpets?

[Rippthrough 98]

What difference is the between running tbs with short/long trumpets?

 

A big chunk of midrange torque + some power.

[Rippthrough 98]

If I go downwards I can do it with room to spare.

 

Now I've just got to try and bend the manifold tube without splitting it again!

Makes it fun to get to the tb balance screws though!

[Sandy 191]

It's an adventure

[Rippthrough 98]

It's an adventure

 

 

Soooo, how well is your maniifold bolted down then

Edited November 23, 2006 by Rippthrough

[TB_205GTI 1]

Talking about nice engine sounds - listen to this vw - by far the best engine sound i ever have heard from a vw..

 

http://video.google.com/videoplay?docid=23...throttle+bodies