Bigger Throttle bodies
Discussion
After some advice on these. Anyone changed theirs at all? The ls1 forums etc seem to talk positively about this upgrade.
Any experience of real world difference it made. I know this could be an interesting mod and had some good feedback from one or two others.
Any advice greatfully recieved.
Any experience of real world difference it made. I know this could be an interesting mod and had some good feedback from one or two others.
Any advice greatfully recieved.
Wrc changed mine and i now have a better throttle response and would you believe better fuel consumption.this might be because of the fact that i only need to rest my foot on the accelerator and the ute takes off.I will be taking the car to Santa Pod so i,ll see how effective it is.I am certainly pleased with the results on the road.
Id say that its perception. For any given throttle position a larger diameter throttle is going to flow more air and hence be equivalent of a smaller diameter body at a more open position. It feels more responsive because its flowing more air at the same throttle position. As mentioned by the previous poster I believe the stock throttlebody can flow more than a tuned stock engine will require.
Rich
Rich
Id say so.
Bold on's in order of benefit IMO are;
- Cold Air Intake
- Cat back exhaust (+ bigger or no cats)
- Headers
- Maf pipe
- Retune (This is good as a number 1, but should be done after each set of mods, so last is best)
Check out www.chipmaster.com.au/Project%20Monaro1.htm
These guys worked their way through all the bolt ons and show the gains made at each point. Its a good graphical single point of reference for starters.
The stock throttlebody and MAF will allow you well into the 400bhp range, Ive seen comments on LS1TECH and LS1.COM.AU of numbers around the 500BHP mark.
Mafless tunes are less forgiving of the environmental conditions and are slightly harder to work out, but will give more power at the expense of engine flexibility, also likely will use more fuel. But some may wish to travel this path. It allows the newer over the radiator cold air intakes to be used, which also gives a ram air effect increasing power.
After this point its pretty much time to get a camshaft in there. Which can be worth maybe 30-50 more bhp. For daily use durations from say 210 to 226 at 0.050 valve lift are best.
Heads are a good idea, but will cost you. If done with the right cam you might be looking at 60-90 more bhp. (Another 30-50 over cam only).
Of course at this point you might need a throttlebody and if your cam is hairy enough maybe even new injectors. You will also definately need new valve springs to handle the increased lift on the cam and depending on the heads some new pushrods.
You can do some nice stuff like increasing compression ratio with new heads though and get more power and economy as UK gas will handle a high compression. The LS2 is 11:1 as it is.
From here it gets real expensive and you are looking at turbo charging, supercharging or stroker motors displacing over 7 litres. Though a 402 cube stroker will set you back $3550US which isnt too bad.. its the rest of the stuff that will cost!
Hope thats helpful, it represents my understanding on things based on years of research and some experimentation on my 5.7L Camaro.
Bold on's in order of benefit IMO are;
- Cold Air Intake
- Cat back exhaust (+ bigger or no cats)
- Headers
- Maf pipe
- Retune (This is good as a number 1, but should be done after each set of mods, so last is best)
Check out www.chipmaster.com.au/Project%20Monaro1.htm
These guys worked their way through all the bolt ons and show the gains made at each point. Its a good graphical single point of reference for starters.
The stock throttlebody and MAF will allow you well into the 400bhp range, Ive seen comments on LS1TECH and LS1.COM.AU of numbers around the 500BHP mark.
Mafless tunes are less forgiving of the environmental conditions and are slightly harder to work out, but will give more power at the expense of engine flexibility, also likely will use more fuel. But some may wish to travel this path. It allows the newer over the radiator cold air intakes to be used, which also gives a ram air effect increasing power.
After this point its pretty much time to get a camshaft in there. Which can be worth maybe 30-50 more bhp. For daily use durations from say 210 to 226 at 0.050 valve lift are best.
Heads are a good idea, but will cost you. If done with the right cam you might be looking at 60-90 more bhp. (Another 30-50 over cam only).
Of course at this point you might need a throttlebody and if your cam is hairy enough maybe even new injectors. You will also definately need new valve springs to handle the increased lift on the cam and depending on the heads some new pushrods.
You can do some nice stuff like increasing compression ratio with new heads though and get more power and economy as UK gas will handle a high compression. The LS2 is 11:1 as it is.
From here it gets real expensive and you are looking at turbo charging, supercharging or stroker motors displacing over 7 litres. Though a 402 cube stroker will set you back $3550US which isnt too bad.. its the rest of the stuff that will cost!
Hope thats helpful, it represents my understanding on things based on years of research and some experimentation on my 5.7L Camaro.
Thanks for that detailed review ringram.
To date I have had:
Headers
New exhaust
CAI
Air filter
Bigger MAF meter
New MAF pipe
Roller rockers
3.91 Diff
Ripshifter
Brakes
Several retunes as I have built up.
Results have been very good and good value. I am afraid I am now caught up a bit in getting more power/torque. This is my everyday car and will be for the foreseable future so it has to remain drivable/flexible.
I was aiming for 500BHP normally aspirated but if thsi is gpoing to cost it might be more sensible to move to forced induction - not sure. Been ina supercharged Monaro and it was ballistic - about 550hp.
As ever it will come down to money!
To date I have had:
Headers
New exhaust
CAI
Air filter
Bigger MAF meter
New MAF pipe
Roller rockers
3.91 Diff
Ripshifter
Brakes
Several retunes as I have built up.
Results have been very good and good value. I am afraid I am now caught up a bit in getting more power/torque. This is my everyday car and will be for the foreseable future so it has to remain drivable/flexible.
I was aiming for 500BHP normally aspirated but if thsi is gpoing to cost it might be more sensible to move to forced induction - not sure. Been ina supercharged Monaro and it was ballistic - about 550hp.
As ever it will come down to money!
Yep, you have done all the core stuff.
My preference would be either a Harrop twin screw supercharger at around $7K Oz for the kit or heads and cam. Which would be around £2500 for the parts if you went AFR205's or £1500 for Patriot Stg2 LS6 type heads. www.harrop.com.au/root_folder/engine_components/stealth_ls112-75.html
The heads and cam wont leave any more room to grow down the NA path whereas the supercharger will give plenty of room. But you are talking about upgrading everything with a SC as you are likely to need a new clutch as well as fuel system, intercooler, maybe even radiator etc.
You can get around 450rwhp with heads and cam no problem.
It just depends on where you want to say "when".
Good luck, no doubt you will let us know which way you go.
My preference would be either a Harrop twin screw supercharger at around $7K Oz for the kit or heads and cam. Which would be around £2500 for the parts if you went AFR205's or £1500 for Patriot Stg2 LS6 type heads. www.harrop.com.au/root_folder/engine_components/stealth_ls112-75.html
The heads and cam wont leave any more room to grow down the NA path whereas the supercharger will give plenty of room. But you are talking about upgrading everything with a SC as you are likely to need a new clutch as well as fuel system, intercooler, maybe even radiator etc.
You can get around 450rwhp with heads and cam no problem.
It just depends on where you want to say "when".
Good luck, no doubt you will let us know which way you go.
I am always dubious about the name "Ram air". It seems to imply that the air is being compressed. This is not the case it’s the temperature of air that makes a difference with these systems. If you change the air intake tract and reduce the temperature of the air, your engine will produce more power/torque. We have all experience the performance change of a cold day spring morning as against a hot summers day.
Good info Ringman!
Good info Ringman!
Thanks Island Boy, check out the G&D OTRCAI and others of similar nature, when running on the highway or down the 1/4 mile the force of air at the front of the engine will create a positive intake pressure. Oz guys recon its worth 3mph down the 1/4 take a look here
www.ls1.com.au/forum/showthread.php?t=34860
"According to tests carried out by David Vizard (How To Build Horsepower Vol 3).
Ram-air is worth 1% @ 90mph, 2% @ 130mph.
Whereas cold-air is worth over 4.5% @ 90mph and 6.5% @ 130mph
With combined gains from both being a simple addition of both percentages mentioned.
i.e. 5.5% @ 90mph and 8.5% @ 130mph."
I agree with your comments relating to standard cold air systems like the stock monaro and hsv's, but these are lined up directly into the throttle body. No bent pipes anywhere.
You can see a pic of these here (post #23)
www.ls1gto.com/forums/showthread.php?t=33164
The guys in Oz swear by them.
www.ls1.com.au/forum/showthread.php?t=34860
"According to tests carried out by David Vizard (How To Build Horsepower Vol 3).
Ram-air is worth 1% @ 90mph, 2% @ 130mph.
Whereas cold-air is worth over 4.5% @ 90mph and 6.5% @ 130mph
With combined gains from both being a simple addition of both percentages mentioned.
i.e. 5.5% @ 90mph and 8.5% @ 130mph."
I agree with your comments relating to standard cold air systems like the stock monaro and hsv's, but these are lined up directly into the throttle body. No bent pipes anywhere.
You can see a pic of these here (post #23)
www.ls1gto.com/forums/showthread.php?t=33164
The guys in Oz swear by them.
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