Solid v Hydraulic lifters
Discussion
I know someone out there will be able to tell me the pros and cons of each, and why some people have changed their setup to solid with (presumambly) new cam profiles.
I know the basic differences (i.e. oil pressure v rods) but can someone give me a rough break down of the differences / benefits.
Cheers
Dave
I know the basic differences (i.e. oil pressure v rods) but can someone give me a rough break down of the differences / benefits.
Cheers
Dave
Cheers Pete,
I know solids give higher RPM but how feasible or beneficial is this in a Rover V8, it's pretty much all over by 5k revs for my standard set up.
If solids & a new cam give you a higher limit do you see any noticeable increase in power? Or do you add solid lifters in conjunction with other upgrades?
Ta
Dave
I know solids give higher RPM but how feasible or beneficial is this in a Rover V8, it's pretty much all over by 5k revs for my standard set up.
If solids & a new cam give you a higher limit do you see any noticeable increase in power? Or do you add solid lifters in conjunction with other upgrades?
Ta
Dave
Solid lifters are only an advantage if used with a cam profile that delivers torque and power at high revs. The engines can be made to rev but this usually requires a stronger bottom end, upgraded oli pumps etc etc etc and you sacrifice low end tractibility usually. It is a pig before the cam comes on line. The solid lifter need adjusting/chceking regularly as failure to do so can result in cam shaft and rocker wear.
Most people steer clear from these and use the hydraulic lifters which are maintainance free and good enough for most cases. However there a few out there that have gone down this route. The 520 engine has them and is producing at 6500 about 200 bhp more than a standard GRiff 500. The 500 starts to run out of puff and the 520 is just starting to stretch its legs... However, below 3000 rpm and it is rough and the gears have to be used to keep it going.
Most people steer clear from these and use the hydraulic lifters which are maintainance free and good enough for most cases. However there a few out there that have gone down this route. The 520 engine has them and is producing at 6500 about 200 bhp more than a standard GRiff 500. The 500 starts to run out of puff and the 520 is just starting to stretch its legs... However, below 3000 rpm and it is rough and the gears have to be used to keep it going.
Marlon said:
Apache,
I've had similar mods to you and max power is delivered at around 5,400 RPM... what could be the limiting factor? If you're seeing power at 6,800 RPM that's a big difference.
Maybe the breathing. What plenum/airflowmeter are you using? I think Pete has an ACT twin plenum with 4.6 airflow like me. Or the mapping (this must be changed I'm told).
gerjo said:
Apache,
I've had similar mods to you and max power is delivered at around 5,400 RPM... what could be the limiting factor? If you're seeing power at 6,800 RPM that's a big difference.
Maybe the breathing. What plenum/airflowmeter are you using? I think Pete has an ACT twin plenum with 4.6 airflow like me. Or the mapping (this must be changed I'm told).
I'm using the twin ACT plenum and V8D trumpets. Standard air flow meter and filter. Mapping has been done on a RR by Mark Adams (twice) - second time with bigger injectors added as Mark said it was dangerously running out of injector duration at the top end... Very smooth delivery (idles cleanly at 1k RPM, pulls from any speed in any gear), loadsd of torque from low-down, but runs out of power way before 6,000 RPM. Cylinder heads are standard 500.
shpub said:
Most people steer clear from these and use the hydraulic lifters which are maintainance free and good enough for most cases. However there a few out there that have gone down this route. The 520 engine has them and is producing at 6500 about 200 bhp more than a standard GRiff 500.
Sorry Steve, didn't understand that bit, is the 520 running on hydraulics?
Apache said:
Sorry Steve, didn't understand that bit, is the 520 running on hydraulics?
Hydraulic lifters are standard on the V8 and TVR. The 520 is running solids along with some very nice rockers. Will rev to 7500+ if necessary but I limit it to a bit lower. No distributor either as this is fully mapped as well which is another weak point with high revs.
Interestingly the original 390 engine also had solid lifters in it as well.... It also screamed its nuts off in a lesser sort of way.
>> Edited by shpub on Tuesday 9th December 15:18
mickypee said:
shpub said,
The 520 engine has them and is producing at 6500 about 200 bhp more than a standard GRiff 500.
Really??
Yep. Look at a standard 500 curve and it is losing power rapidly at 6000 rpm. Many of them including the GRiffs I have had are around the 200 bhp level which is why it is worth changing a bit earlier. The 520 engine doesn't hit peak power until 6400 ish. That's where the difference is. The 520 is at peak while the 500 is rapidly running out of breath. If you take the two peaks the difference is a lot less. And I'm talking real bhp here and not pretend stuff and also unmodified cars which will often help bridge the gap.
The reason is that I have a reasonably wild cam. At lower revs, the Griff 500 would have more power and torque upto 3000 RPM where the 520 would leave it. So I have been a bit selective in picking my reference points.
Not a real comparison in effect because it is comparing a road car with a competion one. This is why I do find driving the Griff a bit like a diesel...
Apache said:
I'm intrigued, how do rockers help then
edited to add, 'I know the valves wont move without em'
>> Edited by Apache on Tuesday 9th December 15:27
1. They look really nice so they have got to be better.
You have blingy wheels, I have bling rockers
I'm not sure that they make things any better but talking to John Eales who built the engine, running reliably at the power and revs that I wanted meant building the thing as strong as possible and then detuning it so that all the components were well within their tolerances. That meant getting the best of everything that was available. John said we need to use these rockers/timing chains etc to get the reliability, then that was what was done. At high revs, the rockers can become a weak link. So they got the Eales treatment.
The engine has been stripped and rebuilt three times now over the last four years and John has seen no wear. It gets done just to make sure and usually so he can add another upgrade to it. The lifters have not needed any adjustment either and the engine has spent a lot of its time at full throttle and very high revs.
Having seen the alloy rockers crack and disintegrate (the ones in the bible came from my Griff 500) the thought of using this type of component and it breaking and wrecking the engine seemed to be a waste so I do go fully along with John's view. If you want reliable, make it as strong as you can and operate well within its limits. It might be overkill but I can floor the throttle without worries.
. Just wondering as these were fitted to mine as part of the rebuild. Shame you can't see them if they are bling bling 
shpub said:
The solid lifter need adjusting/chceking regularly as failure to do so can result in cam shaft and rocker wear.
How often is "regularly" Steve? V8 Developments recommend 6,000 miles, but other people have said that 15,000 is more standard for a fairly mild solid lifter cam... Had the P404 for over 4,000 miles and there's no audible sign that the tappets need adjusting...
Does it vary that much from one cam to the next?
Gassing Station | Griffith | Top of Page | What's New | My Stuff