Jackson Racing Supercharger Owners Thread

[Jrdad]

Originally Posted by tomm.brz

i found a bit funny you have such a powerfull config and no idea/don t care of the boost you are running with honestly

a c38 with high boost pulley will have 10 psi at 6000rpm, 12.5psi at 7000rpm and 14psi at 7400rpm
The problem with this kind of boost is that over time rods will bend...

boost alone isnt what blows your motor. its the amount of power, specifically torque, that does that. you could run two turbos or superchargers of different sizes and they will flow vastly different amounts of air at the same amount of boost. you could also put something in your intake path, which would raise the amount of boost but lower the airflow and thus power that you make and your engine wouldnt care.

[tomm.brz]

if you put something in the intake path, boost and airflow both drop. I.e. the hks supercharger restrictor of 39mm which limits boost to around 0.6, or 43 which then arrives easy to 0.75bar

i agree that too much torque at low rpm will kill rods to the point of snapping (been there) but also 1bar at high rpm can surely contribute to slowly bend rods
I saw csg mike claiking up to 360/380WHP with c38 and high boost pulley, with stock internals and e85.. don t you think the ignition timing used to produce the necessary torque to reach those Whp can't create very high internal pressure inside the combustion chamber? it surely does
what helps is the e85, because with normal pump petrol there will always some moment where a knock can occur at high rpm high boost and in that moment the pressure inside the cylinder is extreme

but also without knocking using only e85, how many people blew the engine anyway even with good reputable tuner? many

[Jrdad]

My apologies, I meant between the compressor and the engine regarding having something in the intake path. The HKS restrictor is pre compressor.

[Breadman]

Originally Posted by tomm.brz

i found a bit funny you have such a powerfull config and no idea/don t care of the boost you are running with honestly

a c38 with high boost pulley will have 10 psi at 6000rpm, 12.5psi at 7000rpm and 14psi at 7400rpm
The problem with this kind of boost is that over time rods will bend, specially if you have no idea what s going on in your engine, or put less octane in tank than required by the tune, every knock with that high boost at rpm can help deteriorating

then suddenly one you get a rich afr, misfires and knock all the time and car doesn t run a shit and you ll notice the compression in cilinders is gone


luckily you use e85 only and that helped, probably you avoided often going to redline too

Sorry to jump back but even at 8k the most i saw in my logs were 1.95bar absolute. Do I have a boost leak?

[tomm.brz]

you also reach 8000 rpm with stock internal stock valve springs?
anyway i dont know if you have a leak, boost depends a lot to intake temperature and are you at altitude or sea level?

Do you have a log of a pull of your car?

[tomm.brz]

Originally Posted by Jrdad

boost alone isnt what blows your motor. its the amount of power, specifically torque, that does that. you could run two turbos or superchargers of different sizes and they will flow vastly different amounts of air at the same amount of boost. you could also put something in your intake path, which would raise the amount of boost but lower the airflow and thus power that you make and your engine wouldnt care.

and 350whp or more with a c38 unit with high boost pulley (that on most car would give about 1bar of boost at high rpm) is not a concerning level of power and torque to worry about the engine?

If i m not wrong Cosworth did engine dyno test and they stated that anything over 0.65bar of boost and 280-300hp to the crank (250Whp or less) is unsafe.. that 's conservative for sure but here in Europe you don t get e85 in many countries

[Breadman]

Originally Posted by tomm.brz

you also reach 8000 rpm with stock internal stock valve springs?
anyway i dont know if you have a leak, boost depends a lot to intake temperature and are you at altitude or sea level?

Do you have a log of a pull of your car?

I'm fully built. I'm sure I have logs somewhere from when I got Zach to tune it. Honestly even being built I'm not a huge fan of going that deep into the rpms but it is nice to have if needed. I'm not a good enough of a driver for it to matter I just found it interesting.

[tomm.brz]

Originally Posted by Breadman

I'm fully built. I'm sure I have logs somewhere from when I got Zach to tune it. Honestly even being built I'm not a huge fan of going that deep into the rpms but it is nice to have if needed. I'm not a good enough of a driver for it to matter I just found it interesting.

oh yes sorry i confused you with the guy Brz866 i responded too

[tomm.brz]

Originally Posted by Breadman

Sorry to jump back but even at 8k the most i saw in my logs were 1.95bar absolute. Do I have a boost leak?

Ok so , the boost i was talking actually is a bit higher than a regulat high boost pulley C38 because the logs i was looking at are with a custom bigger intercooler which adds about 1psi of boost as a result of more restriction, but also cools a lot and logs were taken in Canada with 5 Celsius or less

https://datazap.me/u/tommbrz/v6-0?lo...-34-38&solo=38 Here the boost a high boost pulley C38 can reach when it s pretty cold outside
Mind it's not the RS pulley

[Breadman]

Originally Posted by tomm.brz

Ok so , the boost i was talking actually is a bit higher than a regulat high boost pulley C38 because the logs i was looking at are with a custom bigger intercooler which adds about 1psi of boost as a result of more restriction, but also cools a lot and logs were taken in Canada with 5 Celsius or less

https://datazap.me/u/tommbrz/v6-0?lo...-34-38&solo=38 Here the boost a high boost pulley C38 can reach when it s pretty cold outside
Mind it's not the RS pulley

I have since put vents on my hood due to iat but i checked my last log and it starts the pull at 31c and ends at 44.8c. Pretty sure that would do it

[tomm.brz]

yep, in that log i provided iat is much much lower, therefore the higher boost
big intercooler apparently works good

[Teppka]

Originally Posted by Jrdad

boost alone isnt what blows your motor. its the amount of power, specifically torque, that does that. you could run two turbos or superchargers of different sizes and they will flow vastly different amounts of air at the same amount of boost. you could also put something in your intake path, which would raise the amount of boost but lower the airflow and thus power that you make and your engine wouldnt care.

Does it mean that if I will run it on lower octane gas like RON 95 in Europe I can safely run higher pressure to achieve similar torque value estimated by Jackson Racing or other turbo kit/supercharger kit manufacturers as safe threshold? My understanding is that I will need to increase boost with lower RON gas to achieve similar torque compared to higher RON gas.

[tomm.brz]

that doesnt make sense
the more boost you have, the less the fuel resists
95 ron is so bad that over 0.8 bar the ecu corrects for knock by default all the time basically, ignition timing are so low that the car is just slow and the boost would keep overheating the charge and then it knocks even more

there is a point of deminishing return with boost and shitty fuel...in the same car, less boost and more ignition timing can give more power if the fuel can't stand the pressure and heat

[86Hakone]

Originally Posted by Ignore Your Doctor

damn thats what im getting with the HBP lol. my 93 tune with the c38 was max 9.5psi making around 300whp and I daily drove that for the last 3 years (20k miles) with no issues. now with the HBP im at like 12psi and 360whp so we will see how long she lasts. My car only has 61k miles on it so keeping my fingers crossed

Is the 360 wheel a guess of from a dyno? I'm running c38 HBP, ID1050x injectors, UEL header, With Flex Fuel Kit/Tune from CSG. It would be nice to know i'm creeping up on 400 on a cold day with good fuel. The car feels fast so I haven't bother taking it to a dyno.