9psi and beyond
Discussion
I know I'm going to regret asking this but what's the next step after 9psi? I could get strengthened internals and go 12psi but it's expensive and there seems little increase in performance going by the figures of the recent dyno day.
I currently have 470rwhp and fancy another fix. Should I instead look at polished heads and Cams?
It's a genuine question so advice BASED ON EXPERIENCE would be much appreciated. I've asked Ls1Tech but nobody is answering.
I currently have 470rwhp and fancy another fix. Should I instead look at polished heads and Cams?
It's a genuine question so advice BASED ON EXPERIENCE would be much appreciated. I've asked Ls1Tech but nobody is answering.
Reportedly mine had/has 635 at the flywheel so about 560@wheels. TBO why are you thinking more power as I doubt there is much in it till you get to silly speeds (ie over 150mph). Internals are fine if your going WOT alot but a burst of WOT is unlikely to kill a big V8... IMHO anyhow.
I'm concious not to go OTT on mine and make it unusable or at least a pain for those nice sunday or continent drives as I did with my turbo bike. GO posh wheels and tidy bodywork instead maybe...?
I'm concious not to go OTT on mine and make it unusable or at least a pain for those nice sunday or continent drives as I did with my turbo bike. GO posh wheels and tidy bodywork instead maybe...?
I too have 635bhp (wortec figs) and real world it gave me +2mph and -0.4 sec over the 1/4 mile based on a 112@9psi.
S600VXR is right, you need to be really moving to notice the additional power.
S600VXR is right, you need to be really moving to notice the additional power.
Edited by crisisjez on Friday 15th February 20:57
Edited by crisisjez on Friday 15th February 21:34
Heads and cam for sure. You would want the 122 though to push the air through.
Something like afr or tfs heads with a blower cam. I recon you would get an extra 100rwhp easy with the 122 intercooled and heads and cam.
Try and look on ls1tech or ls1gto.com for "maggie heads and cam" or similar. The magnusson is the harrop equiv with same eaton parts for US stuff.
Like this http://www.ls1tech.com/forums/showthread.php?t=804...
Talk to Stevie he will tell you that heads and cam is a good idea. (I think)
Though if you are going that route, consider a stroker engine and blow that
Then you get your heads, cam as well as forged stuff. Bullet proof and silly power.
You need to figure out your power requirements first then go directly there. Sounds like you would like a stroker.. see the related recent post ..
Something like afr or tfs heads with a blower cam. I recon you would get an extra 100rwhp easy with the 122 intercooled and heads and cam.
Try and look on ls1tech or ls1gto.com for "maggie heads and cam" or similar. The magnusson is the harrop equiv with same eaton parts for US stuff.
Like this http://www.ls1tech.com/forums/showthread.php?t=804...
Talk to Stevie he will tell you that heads and cam is a good idea. (I think)
Though if you are going that route, consider a stroker engine and blow that
Then you get your heads, cam as well as forged stuff. Bullet proof and silly power.You need to figure out your power requirements first then go directly there. Sounds like you would like a stroker.. see the related recent post ..
I was put of the AFR heads for some reason and I think they make less power then the Trick Flow heads. I bought TF heads for a customer and was thoroughly impressed with the quality and the price was pleasing so they have to be worth considering so long as the compression's right for you.
I agree with Richard, Stevie is a person who's really hammered his engine (18 psi comes to mind)with a s/c so he's probably the most qualified person you could ask on this forum
I agree with Richard, Stevie is a person who's really hammered his engine (18 psi comes to mind)with a s/c so he's probably the most qualified person you could ask on this forum
yeah Im leaning to tfs, they have a better valve angle which increases piston clearance so you can run higher lift. Only problem is that you need to run roller rockets with them due to bronze guides (though most all aftermarkets are bronze). Plus new pushrods etc. Still in for a penny..
I've been thinking about the 427ci whipple monster Mark was was working on that had 700rwhp (yes, I saw the dyno sheet) and want mine to be the same. I know it's stupid but I suppose I want a similar thrill from the car as my bike. How come S600VXR has 630bhp and mine is nowhere near that?
Do you think Trick Flow heads are the way forward?
Do you think Trick Flow heads are the way forward?
Edited by anonymous-user on Friday 15th February 22:22
Now now, dont start another dyno number war 
Just go by trap speeds, or turn up at the same dyno on the same day for a better comparison.
The dyno day everyone did at vixpy's was a good mod to mod comparison. No point even starting on that topic when comparing different dyno brands.
Dyno's are for tuning not measuring accurate engine bhp.
Just go by trap speeds, or turn up at the same dyno on the same day for a better comparison.
The dyno day everyone did at vixpy's was a good mod to mod comparison. No point even starting on that topic when comparing different dyno brands.
Dyno's are for tuning not measuring accurate engine bhp.
Trickflow, Dart, AFR, Allpro, Edelbrock, ETP, hell, even the Patriots !!!!
They will all perform well, and TBH, I really doubt size for size, one is way above another in terms of performance ( well in the aftermarket castings anyway, unless going for huge runners )
But yes, heads are always worth it IMO. With perhaps an added bonus, of allowing you to go for a larger combustion chamber, to lower the CR a bit. The pistons are still weak, but a lower CR will keep you that little bit further away from the risk of detonation, which is always good.
But I do say a small drop. If you are sticking with an otherwise standard engine, I wouldnt even venture as low as 9.5:1.
Until late last year, i was using a pair of Edelbrock heads. Im now using a pair of Trickflow 225's. On paper at least, they seem to outflow everything size for size. Whether this will be reflected in terms of power...I dont know. They dont seem to be as popular in the US from what I read on LS1Tech though. ETP and AFR would be the most popular. I think AFR get a big vote, as they were the first aftermarket head out there, so are well proven..
The Darts cant be overlooked though, simply in terms of price.
As for cam....thats a different ballgame, and as Im sure Richard will tell you, will add a LOT of labour costs to fit. Heads can be a fair bit, add a am and its a massive amount of work. Ive done an in-situ swap on my own car, and Im sure your cars would be even more work..
So if it was me, Id tend to go for heads, well before a cam. If engine out...then by all means throw a cam in there.
But do bare in mind. If you do fit heads, you will likely see a fair drop in boost, unless you adjust pulley sizes to compensate for the extra air the engine will consume.
And given the boost drop you will see..it begs the question, if you cant pulley up to regain that boost....perhaps you might want to leave the CR high.
One thing a lot of you guys arent considering as a next step, and its a relatively easy one, and wont cost the earth. Methanol injection. A small squirt, can make a big difference to intake temps, ign timing available, and hence power.
The only downside is that if it was to stop working....you could run into engine problems.
Some say you can tune/map in a safety measure using intake air temp to recognise the cool temps as meaning methanol is being injected, and adjusting timing and fueling to suit. Which is do-able.
Snow, Alky Control, Devils Own, Cooling Mist, Alcohol Injection Services are all some offerings.
Aquamist is another, but UK based, but they dont quite flow as much, so are better suited to low power cars, unless you start running dual pumps etc, which really bumps the cost up..
They will all perform well, and TBH, I really doubt size for size, one is way above another in terms of performance ( well in the aftermarket castings anyway, unless going for huge runners )
But yes, heads are always worth it IMO. With perhaps an added bonus, of allowing you to go for a larger combustion chamber, to lower the CR a bit. The pistons are still weak, but a lower CR will keep you that little bit further away from the risk of detonation, which is always good.
But I do say a small drop. If you are sticking with an otherwise standard engine, I wouldnt even venture as low as 9.5:1.
Until late last year, i was using a pair of Edelbrock heads. Im now using a pair of Trickflow 225's. On paper at least, they seem to outflow everything size for size. Whether this will be reflected in terms of power...I dont know. They dont seem to be as popular in the US from what I read on LS1Tech though. ETP and AFR would be the most popular. I think AFR get a big vote, as they were the first aftermarket head out there, so are well proven..
The Darts cant be overlooked though, simply in terms of price.
As for cam....thats a different ballgame, and as Im sure Richard will tell you, will add a LOT of labour costs to fit. Heads can be a fair bit, add a am and its a massive amount of work. Ive done an in-situ swap on my own car, and Im sure your cars would be even more work..
So if it was me, Id tend to go for heads, well before a cam. If engine out...then by all means throw a cam in there.
But do bare in mind. If you do fit heads, you will likely see a fair drop in boost, unless you adjust pulley sizes to compensate for the extra air the engine will consume.
And given the boost drop you will see..it begs the question, if you cant pulley up to regain that boost....perhaps you might want to leave the CR high.
One thing a lot of you guys arent considering as a next step, and its a relatively easy one, and wont cost the earth. Methanol injection. A small squirt, can make a big difference to intake temps, ign timing available, and hence power.
The only downside is that if it was to stop working....you could run into engine problems.
Some say you can tune/map in a safety measure using intake air temp to recognise the cool temps as meaning methanol is being injected, and adjusting timing and fueling to suit. Which is do-able.
Snow, Alky Control, Devils Own, Cooling Mist, Alcohol Injection Services are all some offerings.
Aquamist is another, but UK based, but they dont quite flow as much, so are better suited to low power cars, unless you start running dual pumps etc, which really bumps the cost up..
Edited by stevieturbo on Saturday 16th February 00:09
Cheers Stevie, that was the sort of response I was looking for. How much, including fitting, would I be looking at for just the heads and another remap. Would it be an option to get my current heads machined or would that be a waste of time?
Richard, you raise an interesting debate there. Mark said the exact same thing - the dyno is a device to set the car up and the figures are just an indication of how much progress you are making when doing so. I looked at several LSV dyno print outs and it was very interesting to note all the cars with the same mods produced the same power give or take 10bhp.
To be honest I'd had a couple of strong ciders when I started this thread and I'm really, really happy with its current performance; it just that tuning is addictive and I probably won't be happy until it blows up!!
ringram said:
Now now, dont start another dyno number war
Just go by trap speeds, or turn up at the same dyno on the same day for a better comparison.
The dyno day everyone did at vixpy's was a good mod to mod comparison. No point even starting on that topic when comparing different dyno brands.
Dyno's are for tuning not measuring accurate engine bhp.
Just go by trap speeds, or turn up at the same dyno on the same day for a better comparison.
The dyno day everyone did at vixpy's was a good mod to mod comparison. No point even starting on that topic when comparing different dyno brands.
Dyno's are for tuning not measuring accurate engine bhp.
Richard, you raise an interesting debate there. Mark said the exact same thing - the dyno is a device to set the car up and the figures are just an indication of how much progress you are making when doing so. I looked at several LSV dyno print outs and it was very interesting to note all the cars with the same mods produced the same power give or take 10bhp.
To be honest I'd had a couple of strong ciders when I started this thread and I'm really, really happy with its current performance; it just that tuning is addictive and I probably won't be happy until it blows up!!
Edited by anonymous-user on Saturday 16th February 12:59
S600VXR said:
Reportedly mine had/has 635 at the flywheel so about 560@wheels.
Nice pub figure! I'd bet anything you like that you haven't got anywhere near 560rwhp.
I have no idea how much some of the mainland guys would charge for fitting heads, and re-mapping. Its just labour really.
But do factor in re-mapping costs, and potential pulley swaps to regain that boost, as fitting good heads really will see boost pressure drop.
As for getting your own heads modified. TBH, given how cheap new heads can be bought, I really dont see the point in that. Paying a UK person to do it, in labour alone might cost as much as a complete pair of heads from the US.
Some of the cheaper ones are around $1200 outright sale...some of the Patriots are even less I think.
Standard GM MLS gaskets work fine, so no sense buying anything that costs more, especially when the GM ones are about $30-40 each or so !! Its all Ive ever used, and Ive never had a problem with them.
I would also say to throw in a set of ARP head studs at the same time. They may not always be necessary, but while its apart, it makes sense.
But do factor in re-mapping costs, and potential pulley swaps to regain that boost, as fitting good heads really will see boost pressure drop.
As for getting your own heads modified. TBH, given how cheap new heads can be bought, I really dont see the point in that. Paying a UK person to do it, in labour alone might cost as much as a complete pair of heads from the US.
Some of the cheaper ones are around $1200 outright sale...some of the Patriots are even less I think.
Standard GM MLS gaskets work fine, so no sense buying anything that costs more, especially when the GM ones are about $30-40 each or so !! Its all Ive ever used, and Ive never had a problem with them.
I would also say to throw in a set of ARP head studs at the same time. They may not always be necessary, but while its apart, it makes sense.
stevieturbo said:
One thing a lot of you guys arent considering as a next step, and its a relatively easy one, and wont cost the earth. Methanol injection. A small squirt, can make a big difference to intake temps, ign timing available, and hence power.
The only downside is that if it was to stop working....you could run into engine problems.
Some say you can tune/map in a safety measure using intake air temp to recognise the cool temps as meaning methanol is being injected, and adjusting timing and fueling to suit. Which is do-able.
Snow, Alky Control, Devils Own, Cooling Mist, Alcohol Injection Services are all some offerings.
Aquamist is another, but UK based, but they dont quite flow as much, so are better suited to low power cars, unless you start running dual pumps etc, which really bumps the cost up..
Ive just brought the coolingmist kit for my car, its being supercharged (9psi) on monday by monkfish.The only downside is that if it was to stop working....you could run into engine problems.
Some say you can tune/map in a safety measure using intake air temp to recognise the cool temps as meaning methanol is being injected, and adjusting timing and fueling to suit. Which is do-able.
Snow, Alky Control, Devils Own, Cooling Mist, Alcohol Injection Services are all some offerings.
Aquamist is another, but UK based, but they dont quite flow as much, so are better suited to low power cars, unless you start running dual pumps etc, which really bumps the cost up..
Edited by stevieturbo on Saturday 16th February 00:09
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?Vi...
My question is ive had it on other turbocharged cars ive had in the past and it has been activated by a boost switch so when driving slow (off boost) its not running, on a supercharged car is the boost switch going to work or will it be running all the time? should i just put a switch on the dash so i can turn it on when im driving spirited or invest in one of there controllers?
http://cgi.ebay.com/ebaymotors/Coolingmist-varicoo...
Edited by jamiep on Saturday 16th February 15:03
Stevie, Thanks, I'll speak to Mark and see how much he'll do it for all in. I might be able to shift my standard heads through Fleabay.
In your experience, how much extra power can I expect from new heads assuming I restore boost to 9psi? I want to work out if it's really worth it?
I also found this: www.gmhightechperformance.com/tech/0601htp_gen_3_gen_4_cylinder_head_guide/index.html
In your experience, how much extra power can I expect from new heads assuming I restore boost to 9psi? I want to work out if it's really worth it?
I also found this: www.gmhightechperformance.com/tech/0601htp_gen_3_gen_4_cylinder_head_guide/index.html
Edited by anonymous-user on Saturday 16th February 15:06
Unless you do the pistons as well regardless of how much extra hp the heads will give your tuner WILL build in a safety margin to prevent the pistons from detonation damage.
Bottom line you`ll have the power, as long as you don`t use it, which is pointless.
It`s going to really cost for the next 50hp.
Bottom line you`ll have the power, as long as you don`t use it, which is pointless.
It`s going to really cost for the next 50hp.
Edited by crisisjez on Saturday 16th February 16:51
VXR_Daz said:
S600VXR said:
Reportedly mine had/has 635 at the flywheel so about 560@wheels.
Nice pub figure! I'd bet anything you like that you haven't got anywhere near 560rwhp.
crisisjez said:
Think it was 560 at the hub`s if it was the Wortec fig`s
Lads, it does what it says on the box, Jez today lent me his car to test it out at Goodwood, no, no not on the track but up Goodwood hill, and that Mother 
er sure could shift, and worse than that he took my son out in it, now all I keep getting is "dad when are you going to get a super charger" Oh thank's jez!!!No muckin about, thanks Jez.
Oh and you should have brought your helmet!
slackalice said:
crisisjez said:
Think it was 560 at the hub`s if it was the Wortec fig`s
Lads, it does what it says on the box, Jez today lent me his car to test it out at Goodwood, no, no not on the track but up Goodwood hill, and that Mother
er sure could shift, and worse than that he took my son out in it, now all I keep getting is "dad when are you going to get a super charger" Oh thank's jez!!! No muckin about, thanks Jez.
Oh and you should have brought your helmet!
Having seen the speeds you were flashing around the track count yourself lucky you had already had a go.
And as for a crash helmet
Out with you...yeah right
Gassing Station | HSV & Monaro | Top of Page | What's New | My Stuff