Small port getting busy... Problem sorted :))

[jondee86]

I've noticed that the small port gets very busy over 6000 rpm !! By this
I mean top end noise... cam on buckets I would guess. The engine is bog
stock, and runs fine. Winding it up, its just exhaust growl up to 6000 and
them a big rush of noise... like hail on a tin roof

Could some of you small port pilots tell me if this is normal for a small
port ?? I can't say I ever noticed the same thing happening on my big
port engines until I was pretty much red lined, and even then it wasn't
anywhere near as loud.

Cheers.... jondee86

[jondee86]

Kind of hard to believe that no-one ever redlined a small port

Cheers... jondee86

[gepsk8]

nah, don't think mine does but if ur picked up on a sound ur always gona hear it, as ur tuned into the sound.
can take for a drive in mine if u wanted?

[blackie]

dont recall my brothers/mates smallport 4ages making such noises ...

[RS13]

Mine doesn't make that noise, just a constant "scream" to redline.

[AE85coupe]

mine has huge amounts of intake noise from about 5000 or so onwards, but not a hail on tin roof noise haha

[gordon77]

yeah mine just screamed all the way to red line too no funni noises, just smallport goodness

[pc]

detonating?

[Cahuna]

The smallport in my Corolla is fine, no strange noises when reving (a couple of unidentified ones when idling though).

Could it be a loose bolt somewhere? The Sentra had a strange rattle at high revs that sounded like it was about to drop its guts, turned out that the bolt holding the alternator on had worked its way out and was causing a vibration at those specific revs. Tightened the bolt and it was all good again.

[solitaire]

Mine screams to the point where you cant hear yourself think... so i wouldnt know...

Having said that mine makes a tapping noise untill the oil has covered everything when cold... and i can only hear that when in front of it...

[jondee86]

Thanks for the comments. I think I'll just live with it for the time being.
Possibly the valve clearances have opened up a bit, and I might have to
do the shims when I drop my new cams in

Cheers.... jondee86

[jondee86]

Well I finally discovered what was causing this noise. The hydraulic
line (steel tube) from the clutch master to the clutch slave has no
clips or brackets... it just runs clear of the bodywork and is held at
the ends. It twangs like a guitar string when you tap it, and it clears
the bulkhead by at least a fingers width.

However, the tube has a resonant frequency at 6000 engine rpm, and
gets the major vibration going... enough to cause it to thrash itself
against the firewall like a beserk vibrator !!! This gave rise to the "hail
on a tin roof" sound you could hear inside the car.

Weirdest thing I ever came across, but a couple of bits of rubber fuel
line slit and slipped over the hydraulic line solved the problem. I got
my redline back, and it sounds sweet

Cheers... jondee86

Oh, it would have been nice to have discovered this before I invested
in a new clutch, pressure plate and throwout bearing But hey...
now I know that everything is in top condition

[frost]

good to hear your engine is all sweet.

on a side note those AGX look really good. are they for your 86? can u give tell me any specs on those shocks?

[jondee86]

Yup... will be going in once I get a set of front strut casings chopped
40 mm and some spacers made up They are the classic SW20
front inserts (4-way adjustable) and Camaro rears (8-way) combination
recommended by Gabe Tyler from T3.

I have the part numbers and dimensions if you want them.

Cheers... jondee86

[frost]

oic. i was going to get the ae92 fronts and camaro rear's. was there a reason gage said the sw20's instead of the ae92?
im thinking of using ae92's because i don't know the full extended length of the sw20 shocks. the ae92's are like this.(thanks GD)
Body length: 336mm
Extended length: 500mm
Extended minus Body: 164mm.

thats the closest i could find to tokiko hts s/s at half the price.
if you can do the same measurements on the sw20's for me that would be great. and the part numbers please

[jondee86]

Oops.... oh well, might as well use this box since I can't delete it

AE92 inserts have about the same cartridge length, but the extended
length and stroke are shorter than the SW20.

HTS102 inserts have :

Lmax = 476 mm
Lmin = 350 mm
Cartridge Length = 332 mm
Stroke = 126 mm

Nice shocks for a track car, but getting kind of short in travel for a
road car that has to deal with typical suburban NZ streets.

Cheers... jondee86

[jondee86]

For measuring and comparing inserts, you need these dimensions :



I chose the SW20 front inserts (KYB Part# 765 015), and I have
measured these myself as follows :

Lmax = 517 mm
Lmin = 354 mm
Cartridge Length = 338 mm
Stroke = 163 mm

The threaded end of the rod is inside the top hat and plays no part in
suspension travel calculations. Also remember that the rod does not
retract fully into the body.

With the springs I have at the moment, I have about 32 mm of travel
on the compression stroke before the OEM bumpstop bottoms out.
With the new inserts I will have around 68 mm of compression travel,
and maybe 60 mm of extension travel. Thats around the minimum
required for a road/Targa car.

Race cars... the stiffer the better, as the actress said to the Bishop

Cheers... jondee86

[frost]

thanks for the info. i'll get the same set up as you got next week.