Head Reworking?

corsaZ22se

wheres the best place to go for cylinder head flowing, larger valves? tried CHD in the past but not happy with his work at all. used Ashford motor sports and very good only very slow turn around times, 8 weeks plus.

MikeS

really

what happened at chd ?

he refurbed a coscast xe head a few yrs back

vocky

it's only the exhaust ports which are restrictive, they need opening up to the same size as the gasket

corsaZ22se

CHD charged for new guides and didnt fit them, skiming looked like it had been done with an anglegrinder didnt match ports anywhere near the size of the gaskets. that was on my coscast x20xev head. allready taken exhaust ports out to the size of the gasket and matched ports on dbilas exhaust manifold. just taken rough castings out of the inlet ports. would like to have larger valves and more flowing done to get some more gains but keep it n/a.

vocky

you will not get much more out of that head by fitting larger valves, what you need to do is remove the balancer shafts and skim the head by 1mm - this will raise the compression to 11:1.
Those two mods will allow your engine to reach 200bhp - if the ecu can be mapped.

If you replace the cams and fit stage 2 with a standalone ecu you should see well over 200bhp, with stage 3 cams over 215bhp.

For a guide the vx220 with webcon throttle bodies have been mapped and stage 1 cams (schrick) gave about 205bhp, stage 2 cams gave about 220bhp and stage 3 over 230bhp

corsaZ22se

i have been looking into throttle bodies but not sure if i want them on this project and if the emissions would be low enough to pass an mot with out fiddling the map each time and taking it some where that likes moddified cars. the mot tester around here are realy hard on moddified cars, i have to make a 90mile round trip to get my throttle bodied b mot'd. seems a very big gain for very little work?

vocky

they all have 11:1 CR, ported heads, balancer delete, 4-1 manifold and full 2.5" exhaust (plus lightened flywheels which don't alter the bhp)

So the cams and mapping are altering the maximum bhp 🙂

wazzavx220

vocky said:
you will not get much more out of that head by fitting larger valves, what you need to do is remove the balancer shafts and skim the head by 1mm - this will raise the compression to 11:1.
Those two mods will allow your engine to reach 200bhp - if the ecu can be mapped.

If you replace the cams and fit stage 2 with a standalone ecu you should see well over 200bhp, with stage 3 cams over 215bhp.

Dear Vocky,

Are the above power estimates with a standard single throttle body? Thanks.

vocky

you would also need a 4-1 exhaust manifold and a decent flowing exhaust system, plus a 2.4 manifold and ported throttle body with a 70mm intake system.

fone

Heres one for you vocky. Just had my ported head back from a skim,and he said ive got the inlets too smooth? rough them up a little!

evocarlos

i was under the impression the inlet side did not need touching just zorst side
more turbulent is better ?

corsaZ22se

on my xev its smoothed and ported but not as smooth/polished as the exhaust side. to much turbulence will restrict air flow, to little will reduce air/fuel mixing.
this head was port matched by me and flowed by cosworth.

evocarlos

corsaZ22se said:
this head was port matched by me and flowed by cosworth.

show off 🙂

corsaZ22se

evocarlos said:
show off 🙂

its a coscast head too! their price for flowing wasn't anymore than CHD only they take much longer to do it. still you cant rush top quality work, as you know carl! (y)

fone

I took casting lines out and then polished to a high shine. Sand paper it is then, hours of work down the pan! 🙁

vocky

won't make any difference on a z22se engine, the injectors spray directly onto the valve heads, so the swirl is created there rather than in the inlet port 🙂

Mine were highly polished on my engine 😃

fone

Cheers vocky,put my mind at rest there. what would i do without you lot on here ay?! 🙂

fone

Talking injectors right! these standard 1s have 2 holes,1 for each valve,but myquestion is, i have some z20let injectors spare with 4 holes! any point in servicing them and using them?

evocarlos

fone said:
Talking injectors right! these standard 1s have 2 holes,1 for each valve,but myquestion is, i have some z20let injectors spare with 4 holes! any point in servicing them and using them?

have read the standard z22se injectors are good for 200hp
only issue with LET injectors are there ev1 plugs and not the same as the z22se ev6 ones so you need to cut the old ones off and fit new plugs £13 ebay 🙂
LET are good for 270hp

might be worth considering adj fuel pressure reg to lower the duty cycle on the standard ones

edit

fone

I see. or more like I diddnt see the plug difference before :whistle: Not going much over 170 on this engine i rekon? balance delete,porting and 200 cell only.
Have bigger plans for another if i can pull this off? :LOL: