Tried searching the archives but found nothing. Basically is it worth doing "half a job" doing just the pistons? I'm running 1bar at the moment on the standard turbo.
If I get a hybrid, what boost can I run with standard pistons?
And with forged pistons and standard rods and crank?
Its not just about what boost, its also about how much torque you are making and what revs you are using it at.
As a rule of thumb though the standard are good from 350bhp at least if used with ARP rod bolts and new bearings, in fact TFS was running 400BHP plus on his with worn bearings and standard rod bolts and it still took over 18 months to die (but that was running nitrous, you cannot get the same power from the same bottom end as safely without nitrous, as nitrous power is gentler on the engine)
Compression ratio will also make a difference, the actual pressure the pistons are subject to for a given level of boost is lower and over a longer time period on a lower CR motor, so a thicker head gasket or lower CR pistons will allow the rods to take more bhp than standard as well.
Personally iwouldnt bother changing the rods on a LET unless you are going for more than the 400bhp ballpark if you are building the rest of it sensibley.
The load's are not the problem its the cycling. A rod fails after so many cycles.
It could probbaly take a compression load of a few tons for a million years, same if it had a few tons clinging on to it.
But when your doing both thats when the trouble arises, thus aftermarket rods etc usually come with a cycle life, like 10million cycles at an equiv of 7krpm.
Some rods will go and go, others will fail sooner.
A little bit, im just waiting for one of the non-nitrous users on here with a cally turbo to do tens of thousands of miles with 400bhp+ though, and then ill have some examples of cars that dont use nitrous.
As it is though, as far as im aware no one else on here at the moment can match TFS's time so his car is a good exmaple of what works and what doesnt.
If he had just done the rod bolts and bearings like i told him to his original engine would still be fine, so it shows the rods are good for 400 easy.
12.9 seconds up the pod in a non stripped out car (including stereo and that bottle you keep going on about being so heavy) very clearly puts it in the 400bhp ball park, timing slips are a far better judge of power (given a consistant driver) than imaginary figures from rolling roads which vary so wildly.
hey, didn't your standard engine (bar Phase 3) cally do a almost dead 13 sec quarter quite regularly, without nitrous or any other means of artificial support ?
hey, didn't your standard engine (bar Phase 3) cally do a almost dead 13 sec quarter quite regularly, without nitrous or any other means of artificial support ?
hey, didn't your standard engine (bar Phase 3) cally do a almost dead 13 sec quarter quite regularly, without nitrous or any other means of artificial support ?
yea last yr at pv2002 russ did v low 13's i think he got a 13.1...so a 12.9 with 400 bhp is not that great...he should have been into the mid 12's or low atleast
As several have said, (thanks, until now I thought people didn't like me ) 13.1's are achievable in a fully loaded cally turbo with only a paltry 300bhp.
Now, any one wanna talk about good 60ft times?! lmao lmao
Sorry should have put more detail in my post there for the pedants who wont bother looking at the rest of the facts themselves
i should have said something like
"making a 12.9 still despite blowing up the intercooler before the line and coasting accross in a standard weight calibra after getting a pretty average 60ft time due to crap tyres clearly puts it in the 400bhp ballpark"
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Vauxhall Owners Forum
4.7M posts
72.7K members
Since 2000
A forum community dedicated to Vauxhall owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, reliability, maintenance, and more!