Engine mods

[smiffy 33]

Festive greetings guys n gals
The 33 is sorn no for the winter and hoping to get it garaged and wanted to spend some money on it. I've got a set of buckets and harnesses to fir but I really want to send the engine away for work.
What I would like to know off you fine lot is what's the best way to get hp and lbs/ft out of it.
It's a 1.7 16v and I'm thinking different ecu, adjustable cam sprockets (can't remember the actual name) maybe lightening the crank, different flywheel different cams etc. What's best and where do I find measurements to give to the machine shop.

Thanks in advance
Leigh

[KevJTD]

bryan's your man for info on the 16V, sure he'll comment when he can
Vernier pulleys are what you mean for the cam wheels, quite expensive a thing for them as you need 4 rather then the 2 of lesser cars

i'm at a bit of a crossroads with my 33 16V too, wondering what to do with it so i'd be interested too in what can be done for them without spending thousands....which I know bryan will say you have to to get serious oomph out of them

[Johnboy]

Morning chaps
For starters get shrew to knock up a manifold ! If your keeping your shock ecu? Get an uprated chip . Junk the air box . K&n with big cold air feed . Cams are money and as Kev said so are the pulleys .Also start loosing weight from the car . That's free

[smiffy 33]

The car is already stripped and a roll cage in it. I took the k&n off and stuck a BMC CDA on it.
It goes pretty quick at the moment but would like to make it a bit more quicker. I know the gear boxes are an issue so any help on those too. I've spoke to shrew about an exhaust system and I think that is the way to go. It's got a equal length manifold on it at the moment but keeps breaking on the welds. It will be an ongoing project lol

[PETROLHEAD]

The world is your clamshell Leigh, but how big or deep are the pockets?


A good manifold is great, and of course we're always ready for that no problem, but i'd work on getting a bit more in before worrying about getting it out.


I'm set up for carb conversion initially, (and Kev is considering the route too), which will give better tune control to me personally rather than the crude stock motronic system. It lacks any real processing power and speed, and a quality chip or reflash is very hard to find these days. Most chips, including the commonly known "squadra", have been found to be little more than a higher rev limit rather than the stock hard cut where the map simply ceased to be written!

Whilst ever you retain the stock Air Flow Meter and system, fuelling adjustments really are minimal, and not likely to create any meaningful difference other than running correctly in my opinion.

Bryan / BLS continued to use carbs for quite some time, and making max power was never the issue with them, they made very good power and torque, but revving as high as their engine now does with wild cams to make its outright power meant that carbs will compromise the drivability at lower revs, so the move to fully programmable injection was to iron out the compromises and to fuel better over a larger rev range, Mainly!


Vernier pulleys are available to buy, but i don't see much point of them until your also using some hot cams to dial them in with maximum gain. With stock cams, again the improvements will be very hard to justify against the expense, plus they're quite a faff to set up on a 16v! You could always modify your stock pulleys to be adjustable, which is what i'd likely do to start with.


I've got a pattern for lightening the 16v flywheels, and can machine them up no problem, or if you move to carbs i can also machine a none efi flywheel up to much lighter weight as they don't require the trigger wheel attached as the efi cars do, and the difference between them is really quite large!

The bottom end of 16v engines are quite improved over earlier engines, and should stand considerable tuning before protesting. The cranks and blocks are better, the oil pumps are better, and of course they are also the youngest, so actual fatigue is less of a consideration.

The heads are probably the hardest to improve on, although are potentially an area of notable gain, but with minimal scope for larger valves and porting etc without BIG expense and very specialist expertise, so i'd consider that last personally.



If it were me, today, i'd go carb conversion (40mm+), programmable ignition (Omex or Nodiz), lightened flywheel, and exhaust, and consider that a good "Tune" package. See how you feel about it, and see what you want to spend after that, if anything?



All that said, i'm still seriously considering selling all my current stock of parts needed to achieve the above, in order to fund a turbo conversion, BUT the real world considerations are how far can i go within a reasonable safety margin for the drivetrain, which as you already mentioned yourself, the gearbox is something of an achilles heel!


Myself, Bryan, and Tom were discussing the potential differences of this type of tuning before, and it begs the question, "would you rather have 150/160 bhp you can spank, or 180+bhp but have to nurse the drivetrain?"


Its a risk, but then again, a lightened 33 with 150+bhp is a real world possiblity and would be a hoot to drive!

[BS25]

Shrew has covered most of the points there!

For a fast road/trackday engine and if you want to go carbs or throttle bodies then select from the following or have them all on a carefully built engine:-

Lightened flywheel
Omex management (or similar)
Fast road cams (Catcams do a range) - relatively mild so retaining driveability and avoiding the need for deeper piston pockets
Increase compression ratio
Suitable intake (depending on whether you stay on injection or go onto carbs/bodies)
Exhaust manifold/exhaust from Shrew
Increased capacity sump with baffles (if doing trackdays)
Oil cooler (if doing trackdays)

More power will mean more revs and much more expense from increased capacity, steel rods, forged pistons, steel crank plus extensive head modifications - none of those are off the shelf parts so will be very expensive. Going this route will also entail looking at further water and oil cooling capacity, etc.

Don't forget suspension, brakes and tyres

[PETROLHEAD]

Don't forget suspension, brakes and tyres

Probably need a big budget to compete with the gains to be had from stopping and cornering better, very valid point Bryan

[smiffy 33]

Wow nice replies. I think I had a price of you for the carb setup I'll have a look. Sound nice too a set of carbs. I have recently aquired a 166 3.0 super which has the 4 pot brembos. So I have the brakes. The suspension is low and stiff and handles well if not a bit skittish on rear end. Good info guys cheers

[PETROLHEAD]

Dont forget the rear end of all the boxer engined alfas are quite light, so no need for overbraking or over stiffening at the back end anyway.

Keep it subtle and tracking the lumps and bumps of a public road rather than set up for a billiard table track surface which occurs once in a blue moon!


I had planned to use those same brakes myself at one time, they are huge but surprisingly light which is nice, but you'll need hell of a bracket making to fit them on 33 hubs, and then because of the disc size they are designed for (306mm yes?) you may need to rethink wheels.

The right 15s will do it, but it'd be a lucky man who found he already had them fitted, so you may find yourself in the market for bigger diameter wheels and more radical offset too.

Everything has a snowball effect in this game, but the right approach will give demon results overall

[Johnboy]

Yeah agree with shrew . I've always found the brakes ok on the 33 . On mine I had 16v calipers with tarox disks with omp pads . Worked well . But then I don't stamp on my brakes . But then again,I'm playing with bigger brake setup as shrew knows I've got red koni's that are set 75% hard on the front and 50% on the rear . Worked well me . But it's a personal thing with setup!

[rsfruitbat]

At Rockingham we made loads of time up on people just being able to outbrake them into corners

rsfruitbat

[smiffy 33]

Decided to go with a carb set up so I need to start a shopping/wish list.
Thanks for all the replies guys
There will be loads more questions I'm sure

[smiffy 33]

Me again can someone do me a list of what stuff I need to source for a carb conversion pretty please. What ecu to use and do I need to change the dizzy cap and things like that.
Thanks very much

[PETROLHEAD]

Carbs 40mm plus (weber idf / dellorto drla)
Carb adapter manifolds (NOT the Motorman253 greek jobbies!)
Filters/trumpets/stacks
Modern 4 cylinder ignition coil

Ecu and coil will replace the dizzy anyway, go for something good like Omex 100/200, Nodiz. Etc

Wiring harness, trigger wheel (unless sticking with stock 16v flywheel), throttle position sensor (not switch), and a few more minor knick knacks im sure!


Its costly, but worth it. The bang for bucks is pretty good, and if chosen wisely the kit will support any future work you put into the motor when/if you're ready.


Feel free to come and see what ive assembled leigh if you fancy?

[smiffy 33]

Might just do that

[SteffenJ3316V]

Why not just go with a different ecu like Omex, MS etc and put trumpets directly on top of the TB? You will gain the same amount of power and you won't have any flat spots. A lot cheaper too

[junior]

I have a set of half race cams if they would help you. Not going to be used in mine. PM me if interested.

[rsfruitbat]

Hi Junior

if smiffy isnt interested then I may be.

please can you pm me some details of the cams etc and how much you want?

rsfuitbat

[junior]

John boy just politely pointed out the problem with my cams and your car. They are for an 8v. Hey ho !

[rsfruitbat]

Oops

rsfruitbat

[PETROLHEAD]

Why not just go with a different ecu like Omex, MS etc and put trumpets directly on top of the TB? You will gain the same amount of power and you won't have any flat spots. A lot cheaper too

I'd considered this route too, and came up with the "Trumpets of Valhalla! "

But as for being cheaper, I'm not sure about that, not at our prices over here anyway.

A decent omex, loom, switches and sensor's, install and rolling road tune will set us back circa 1500 quid before anything else

[Johnboy]

Think I'll be on the look for an omex and keep the injection. Junk the air follow meter and plenum .
Dear Santa

[niaugi]

Hello boxers

i neeed these trumpets! i am testing Megasquirt now in 1.6 boxer and later planing to wire MS onto 146 1.7 16v engine, so was thinking droping whole air intake system and fit trumpets would be a perfect tune!

any links or places i can get them?

can they be done height adjustable (for tuning purposes)?
my dream for example..: automatic height adjusting depending on rpm.. higher the rpms, shorter the trumpets..
ok ok i know, they will be static

please post dimensions if anyone knows - how long and wide is best for low/medium/high torque.

if prices are at the sky, i think they can be made at grinding shop, just need some info about specs

I'd considered this route too, and came up with the "Trumpets of Valhalla! "

[PETROLHEAD]

The "Trumpets of Valhalla" were something i came up with and have an engineer turn out to my spec (he's actually the guy that makes half the Webcon catalogue!)

I settled on a long design to put some torque back into the rev range of the 16v motor which is quite peaky, but the have around 20mm of adjustment for fine tuning.

They are also a tapered design starting at approx 45mm down to the throttle bodies which are 40mm, in an attempt to recreate some of the venturi effect that carb chokes have and benefit from, and finally i left the open end as a half radius to discourage hot air entering from the engine heat below.


That was all my plan, but so far i haven't had the chance to fit and run them, but if anyone can pick any holes in the theory i'm all ears and promise not to sulk! lol!



ooh, one more thing

the intention is also to taper the throttle body entrance to smoothly blend the trumpet in, NOT to have the step you can see at the joint on the the photo from above.

[SteffenJ3316V]

£1500

[PETROLHEAD]

£1500

Afraid so mate, and to be honest, it could be more!

An Omex 600 (£650), assembled wiring loom (£180), and a couple of switches and sensors (£200), Trumpets (£100), etc etc, will soon be £1000 plus in new parts alone, maybe a little more, and a typical rolling road session to fully tuned could quite easily be £350, so £1500 total is a very realistic expectation, in fact it might be a little shy!

At least with carbs a lot of the install, parts, and tuning can be diy, and maintaining the tune, or tweaking for other mods doesn't necessarily mean another £300 every time!


but they're are pros and cons for both approaches, and a lot of personal choice and thoughts too

[niaugi]

The "Trumpets of Valhalla" were something i came up with and have an engineer turn out to my spec (he's actually the guy that makes half the Webcon catalogue!)

thanks! collecting all info about them and will try to go this route
maybe you know how long are they?
how about air filters? difficult to get?

[PETROLHEAD]

Off the top of my head, i can't remember what length i made them too, but i will measure them for you in a day or so.

as for fliters, well for road use i would just go with a foam filter sock, either singles or oval twins, but for track days i'd probably leave them open!

[niaugi]

Roger that

[Johnboy]

Trumpet length . What about measuring the length of the plenum legs ? As I believe the later design was a bit higher to add torque. That could be a starting point ?