Hi every body what`s up? , ,have a felicia 96 with 1.6 MPI AEE engine i was thinking of tuning it up so i found some one say that you can change the upper part of the engine from the regular 8 valves to the vw polo 1.6 16v gti AJV engine the 16v one it is the same base but diffrient ins upper part from 8 valve to 16v and i checked the etka 7 about this it is really the same from bottom non diffrent but i was wondering if some one had really tried this and really saw both engines from inside i need help please.

waitting for your replies

erm, yeah the engine block crankshaft and conrods are the same, but the pistons are different, on the 16v engine they have small reliefs cut into the crown for the valves so you would need to change the pistons too or get some cut-outs machined into them, as far as mounting it is concerned, the 16v engine has an extra timing belt idler which uses one of the bolt holes that the engine mounting uses on the 8v engine so you would need to fabricate or bodge together a left hand engine mounting too. you WILL also run into difficulties with the ignition timing/distributor, the ajv and all other late 16v lumps dont have a distributor because they use either wasted spark or indepenant coils (engine code dependant), that said, it is possible to retro-fit a distributor to these engines but it requires a little bit of fiddling

as for the ajv engine.... good luck finding one!!! they were never available in the uk, however it is esentially the same as the lupo/polo gti lump except it doesn't have variable valve timing... but as far as cylinder heads go most of the late 16v engines use the same (or indeed very similar) cylinder heads... in my opinion it would be easier to use the earlier 1.4 16v head from an AFH engine, but you would still have the same mounting and piston issues to overcome

wow so u think that i to go away from the idea of changing the 8v head with the 1.6 16v one , ok what do u think it will help me to really boost my aee engine, i have changed the the exaust system with an HKS it helped alittel but i need something else to make it fly

oh and thanx man about this info it really helped

How practical does the car have to be, and are there any competition regs it needs to comply with?

If not very and no, try stripping most of the trim out.

that is cool what i see you have changed the ecu and the whole intake of the engine and the fuel injectors too u r really good man, so what its horse power now?

erm, roughly zero at the moment

erm, roughly zero at the moment

I know that feeling, projects eh...lol.

erm, roughly zero at the moment

y? did you blow up the engine?

no i'm having problems getting the right amount of fuel in coming off idle, it's because the throttles are so big there is very little air speed in the intake so you need massive amounts of fuel to keep it going, but as soon as the air speed comes up it works fine, i've got a horrible misfire at about 2500 revs too which i cant seem to get rid of irresepective of where i set the ignition advance, but then i am temporarily using the old dizzy cap and rotor, maybe swapping these for new ones might solve it, also i'm going to change the ignition timing reference point fromm 66 BTDC to 50 BTDC, when it's set to 66 i have to retard the dizzy almost to it's limit to get the right base advance setting, so hopefully changing the reference point will get the dizzy somewhere near it'ss centre setting

no i'm having problems getting the right amount of fuel in coming off idle, it's because the throttles are so big there is very little air speed in the intake so you need massive amounts of fuel to keep it going, but as soon as the air speed comes up it works fine, i've got a horrible misfire at about 2500 revs too which i cant seem to get rid of irresepective of where i set the ignition advance, but then i am temporarily using the old dizzy cap and rotor, maybe swapping these for new ones might solve it, also i'm going to change the ignition timing reference point fromm 66 BTDC to 50 BTDC, when it's set to 66 i have to retard the dizzy almost to it's limit to get the right base advance setting, so hopefully changing the reference point will get the dizzy somewhere near it'ss centre setting

Without even trying to claim I know anything like as much as you do about these things, do you think it's going to be something you can fettle your way out of? Only what little air gets into the engine bay won't really circulate around the area your carbs are, I think. Thinking about how old carb cars sometimes had an inlet pipe sucking in from the grille, would some sort of bonnet vent / scoop help?

Tom, if you're getting air stall on low throttle, I think you're pretty stuck. If it's a race/track day engine, you can drive around it, but if it's a road engine you'll probably have to use smaller bodies, or relocate the injectors to fire the fuel more or less directly at the backs ot the inlet valves.

As for the ignition timing, I've a vague notion that that sort of misfire indicates a cracked dissie cap, tracking rotor arm, or bad plug. And yes get the base trigger away from the end stop of the swing.

Ap0gee; you're confusing CAI with port velocity.

Ap0gee; you're confusing CAI with port velocity.

Maybe, but my reasoning was that the position of the carbs would mean that they'd be sat in a nice zone of low pressure as the Venturi effect sucked the air out of the bottom of the engine bay. With direct access to atmosphere, inlet air pressure/density, and thus flowrate could be improved?

Maybe, but my reasoning was that the position of the carbs would mean that they'd be sat in a nice zone of low pressure as the Venturi effect sucked the air out of the bottom of the engine bay. With direct access to atmosphere, inlet air pressure/density, and thus flowrate could be improved?

I thought as much, but ram effect would be worth maybe 2bhp at 150mph, and wouldn't help with low speed running problems at all.

I thought as much, but ram effect would be worth maybe 2bhp at 150mph, and wouldn't help with low speed running problems at all.

Fair enough; I bow to your better knowledge (again! )

it's not the flow rate that is causing the issue,

think of it like this.... you can pump as much fuel into the manifold as you like, but if the air is static (or not moving) then the fuel doesn't go anywhere... there are other factors which affect this too such as flow reversion caused by massive overlap camming

the injectors are already located in-board and firing straight into the back of the intake valve, got new plugs in...

it's looking quite hopeful, there is a massive amount of vacuum at idle, it's literally just the first few degrees of throttle opening that it's faltering at the moment... i'll fire up the emerald software and add more fuel just above the idle site to see what happens

it's not the flow rate that is causing the issue,

think of it like this.... you can pump as much fuel into the manifold as you like, but if the air is static (or not moving) then the fuel doesn't go anywhere... there are other factors which affect this too such as flow reversion caused by massive overlap camming

the injectors are already located in-board and firing straight into the back of the intake valve, got new plugs in...

it's looking quite hopeful, there is a massive amount of vacuum at idle, it's literally just the first few degrees of throttle opening that it's faltering at the moment... i'll fire up the emerald software and add more fuel just above the idle site to see what happens

Yeah, that's what I thought. I'm pretty sure you're running too big bodies for the engine now.