Alfa Romeo Alfetta GTV TBi - Dyno run

Short movie from different dyno runs during tuning day. Close to 270whp @ 1 bar boost 7200rpm.

[gardell]

tip about twinspark.. stay low on ignition timing if you are using both plugs.. i normaly use single plug on twinspark engines.. so i can manage ignition timing better.. be aware of cylinder pressures too.. as tend to heat up pistons. my 8v with only gaskit and pistons was 365bhp with 20psi. but always used water methanol injection and race fuel. never had problems with that for 4 years. i broke liners with 25psi.. now have steel ones.if you do this upgrade check for piston ring material

[wergilius]

@buzzedo1 Some engine facts:

TS (75) crank and modified piston TS (155), treated standard 155 rods. 8.5:1
Standard valve (3 angles), ported head. Camshaft special made Kent cams,
Duration (0 lift) ~302 degrees and lift 10.7 if I remeber correct.
Block filled up to waterchannels, liners modifed with steel o-rings.
Dry sump, electrical waterpump, fully sequential COP and injectors.
Turbo TD04H-19T, ported exhaust house.

[wergilius]

regarding gearbox, it has standard modified diff (48%), the week spot for me is the gears, current setup is a custom bacci/old 116 gear setup, i have fixed stiff clutch and c-joint transaxel (from audi) and 245 race tires so that probably put some stress on the gear.

[wergilius]

i have cop twin spark setup and use 99 octane fuel, but thanx for the heads up, i look into this a bit further

[gardell]

the engine is all as standard.. just high pressure oil pump.. head gaskit grovved in liners.. and arias pistons 8.5.1 compression. and was 365bhp with 20psi

[wergilius]

@buzzedo1
155 piston is cast and a bit sensitive in ring lands, have broke two pistons.

I run boost control in open loop, works great in this application, rods is shot pean and actually
lighter that both Nord and TS rods, piston is lighter as well.

I drop boost to save mtrl only, but so far gearbox is weakest point so far...

But also since this is race only, load is muck more heavy than street machine.

[gardell]

i have 2 twinspark 16v engines.. one fully modified and one not.
my 155 has wossner pistons and racing gaskit. and holds 25psi with 400bhp. never had any problems.. stock head. stock rods. 470 torque. revs 7000rpm.

the other was has everything changed.. its 712bhp. 680 toruqe. and revs 9000rpm

[wergilius]

hi bruce, sounds promising, my engine is eating pistons (broken ring land) so a set of wossner is finally on its way down :) At least one problem less since its eating gearboxes to...

[buzzedo]

intersting, I have about the same Hp on my single spark at 22psi...320Nm of torque at wheels in fourth gear from 4000rpm to redline using supercahrger and garret gt3540 with 1.06 rear. Love to know more about your setup, very nice.

[buzzedo]

thanks for the info, interesting setup. It should be good for more boost I would think (although I am not familiar with what the 155 piston is..forged?). Did you expect the cams to push peak power high? I would liike to push peak power to 7500rpm. Usually overboost is used for the last few hundred rpm, since the heat load drops off between gear change, I hold 25psi to redline, but the head struggles to flow since it is stock. I use o-rings also and standard liners. What grout do you use?

[buzzedo]

Fair enough. I understand. Maybe your propshaft is very hard on your gearbox with shock loading. I also take my car to the track, but run gtv6 propshaft and donuts. I will move to bmw donuts soon as they are much stronger. Gearbox still ok for me. I run 22psi on the track. It is a short track so not much more than 160km/hr. Your car looks like a lot of fun to drive. What exhaust gas temp sensors do you run, I see you tune on exhaust temperature. I do not, but would like to.

[buzzedo]

oh, and mine is at 5600rpm for peak power, just stock cams, would be interested in your cam setup, I'd like to push peak power up the rpm some more.

[gardell]

almost all alfas break the diff. AHMotorsports can provide you.. its the best and its not that expensive. Paul spruell motorsports can help you out too.
about pistons.. the standard ones only been safe with 14psi on my 8v engine.. and break cylinder wall too.. another thing about pistons.. do not use 2618 forge.. cause they tend to get bigger by heat and you will scrach skirts. i have 84.4mm pistons used on the shelf if you like. ARIAS pistons.

[wergilius]

@buzzedo1
No, the 155 piston is cast, i have had some breakdown cause to bad overboost settings
With stock rods i will not go over 7200 rpm i think to save the mtrl

What do you mean with grout?

[gardell]

if you manage to do a full throttle shifting setup will save you a lot of hassle. a spark cut beetween gears..

[maxidutra]

hellow I have te same engine for a proyect is safe put a turbo on this engine if is complete stock ??

[wergilius]

interesting about the ignition, a fellow alfista in our racing series got ignition related damage on his NA TS engine two weeks ago. what do you mean with low in this case, i have 17 degree timing at 17psi boost.

the liners have steel rings and is fixed in the block so it is a bit of hazzle to change, my set of wossner pistons is already ordered but thanks anyway.

[buzzedo]

Overboost is due to poor boost control, not a properly tuned boost level. If you run lets say 15psi at 6500, then you cna run 15psi at 7200...No reason to back off is all i am saying. I revved sock alfa rods to 9000rpm with shot peaning, no problem

[gardell]

beware dont skip 20psi boost.. standard liners will crack.. or deform and damage yr pistons. Are you using single plug per cylinder or two ?. if you have 2 plugs.. 17 is too much. with single plug at 17 psi boost i have 14deg at 4000rpm and raise up to 16 at 7000rpm. with water injection and race fuel.

[wergilius]

what cr do have on that setup, I have 8.3:1 since I using another cranshaft and slightly modified pistons