The V8 Owners Forum -

Hi guys,
i know where there is an old Rovertec engine,
cc wise not sure,
but it has cossie 95mm pistons fitted, what size could it be 4.5????
engine condition unknow as such as not been run for a while, it has a pair of ported and polished Rovertec heads also on it,

does any one know any info regarding the old Rovertec units?? as want to find out it they are forged pistons (more nitrous )
Oh they have 4 cut outs in the crown also,

Is v8 developments the renamed Rovertec???
Not sure if Rob has joined the new forum as would ask him regarding the engine,

v8 is the renamed rovertec. Pistons sound like stock cosworth 2.0 which will be mahle's unless aftermarket forgings. Depending on the stroke capacity could be from 3.9 to 5.0 ish. I'd guess at it being a 4.5 though or less.

Boosted.

cheers Mike,
how can i tell if forged???

How to tell forgings, the only way is to inspect the underside of the pistons, you may be lucky and there will be a part nimber etched onto the bottom of the gudgion pin area, if not you have to inspect the underside crown for flashing forgings tend to be smooth with smooth transitions in the joins where the toolong meets, castings have possibly ground areas where the flashing should be but is rarely ground off under the gudgion pin area,

cheers,
i'm hopefully going to look at this engine next week,
if we decide on a price i may have to sell off my 4.6 heads to help pay for it so car will be off the road for a while.

Tony, that piston i gave you is a ofrged cosworth one, all cossie pistons have part numbers (i phoned them) so compare the pistons on the rovertec with the one i gave you. If they're mahle ones used on the YB then i think they mahle on them.

If in doubt pop one out and have a look see!

Like Ian said. castings tend to be cast from 3 seperate parts so you see lots of flashing underneath the crown. Forgings always look like a one piece item and are nice and smooth, everywhere. Sometimes they have machining around the crown for the bowl and pin bosses. Castings don't need machining.

I get stuck occasionally. I have 944 turbo pistons here which are really good. So good I can't tell if they're cast or forged. I suspect they're forged:) but they could be cast

Boosted.

i'll take the camera with me and take a couple of pics,

The block:


The 95mm pistons with two valve cut outs not four:






Engine Number:


Rtec stg2 heads.




The engine is,
71.12mm stroke,x 95mm bore .= 4032.91cc (246.1 ci) or 4.1????

Right now the history,
Phil (neils friend) bought this engine for his car,
BUT they had over heating issues from day one of the install, as it would dump the water out at any opertunity,
the car went well though even with this problem,
they changed the carb and inlet manifold thinking this was the prob and fitted efi, which seemed to agravate the problem further.
All 8 pistons are black not steam cleaned as if it was pressurising the bore,
could one of the heads be susspect???

Also can we make up some sort of set up to pressure the water ways to see if there is a leak on a liner or on the block and heads???

we were going to blank off the water way on the block face with a plate and gasket with a pressure gauge fitted, and fit a plate the other end of the face to block it off and then fit another plate with a valve for the air line at the block front (water pump inlet),
if this is ok what pressure do we have to test it too and over how long to see if a drop??

we will do a similar thing with the heads then,

the other block to the left of the rovertec one is another 3.9 which if the RT engine is buggered will use this as a base to rebuild the RT engine into,
I hope to have both engines here in the week when i will strip th RT one down to a bare block and test if we can or send away to be tested.

watch this space:

If the block turns out to be ok,
what cam would you guys recomend to fit this engine???

Don't know what you want to do with the engine but a 218 is a very good all rounder. Raceier cams lose bucket loads of torque for only a few hp gain.

As for pressure testing the block what you propose should work. Stand it on end and get all the air out of it. Biggest radiator cap is about 15 psi so I'd suggest that testing at that pressure would be ok but wait a while for leaks. Or, test at a higher limit and don't wait as long

Boosted.

how long would you recommend leaving the block for when pressurised mike?????

Neil delivered the block last night (tuesday),
and tonight (wednesday) started to strip it down ready for pressure testing to see if it has a liner problem,











As you can see the block is very clean inside,
and to my surprise when i removed the sump it has ARP main studs, (one less thing for me to get )
Do you think the crank etc has been balanced?? as there are a few polished marks (shiney metal) on the crank and some fresh drill holes (as in picture)

And has anyone seen these pistons before???
only markings are as in the photo's
9525 and GPM

Pistons are quite primitive, defo not Cosworth items. Look like cheapies to me but they will be up to the job, just or wouldn't have been fitted. Could be Silvolites or another brand of eutectic. They're certainly cast, not forged. Oh, here they are.

http://home.clara.net/captain.norton/cnn3sec35.html

Bit crappy for really performance use as are hepolites. Mind you, I do see pin oilers there so that's a plus


As for pressurising the block, go for a high pressure for say 5 minutes. How high can you go? If you don't get a leak then, you haven't got an issue. In some ways it's more likely the combustion chamber will pressurise the coolant, just imagine how much pressure there is in a cylinder at tdc.

cheers Mike,
all i can find are bike pistons by GPM lol.
so they are cast then, hope they can handle some nitrous,

My crank and rods looked the same as yours after it had all been balanced so i reckon yours has had the treatment too. Are those arp bolts in the rods?