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Posted: Wed Jul 02, 2008 7:34 pm
by chodjinn
Hmm can't seem to find any suitable pushrods anywhere. I need the cup and ball type, not ball & ball like standard. Any suggestions?
Posted: Thu Jul 03, 2008 12:07 pm
by chodjinn
Well after speaking to a bunch of people, the only place I can find that will make me some pushrods is JE Developments, and they want £16 per pushrod, which is about £260!!! Way outta my budget. Looks like I've wasted yet more money on useless RV8 parts!
Posted: Thu Jul 03, 2008 1:50 pm
by kiwicar
http://www.compcams.com/Technical/CurrentCatalog/
Might be worth a hunt on here, buick 215 to them (under GM stuff)... they will take orders by E-mail, they don't understand english very well (I am not joaking!!). otherwise find the part on the catalog then use summit's online shop then you don't actually have to talk to anyone.
Mike
Posted: Thu Jul 03, 2008 2:22 pm
by Wotland
Posted: Thu Jul 03, 2008 2:24 pm
by chodjinn
cheers, but I'm struggling to find info regarding the length of pushrods, and the size of the ends. I'm scanning the search function as I write this . . .
. . . and not come up with anything useful or consistent. can anyone help me out here I'm at my wits end

Posted: Thu Jul 03, 2008 5:54 pm
by CastleMGBV8
Ollie,
It's not the case of just ordering up a set of pushrods, if you are changing components within an engine and having any machining done then the rocker geometry will need to be adjusted especially if using a cam with a fair amount of lift.
You effectively have to build the engine, and then test assemble the valve gear and then calculate what length of pushrod is required even if using adjustable rockers, you may have to machine the rocker pillars to obtain the correct relationship between the rocker tips and valve stem.
Sods law of engine building, change one component and you will have to change at least three others. I know I have just done this and am still setting up the valve gear
If you are going to use a fairly soft cam as it's a turbo application and don't need to rev above 6000RPM then virtually standard rocker/valve gear will be fine and will save you a lot of hassle and money.
Do you have Des Hamills book, if you intend to build engines it's extremely informative.
Kevin.
Posted: Thu Jul 03, 2008 6:08 pm
by chodjinn
Bah! I knew it! It's never easy lol
Well, I know that I don't really need fancy valve gear for my current set up, but I plan on building a high power twin turbo motor, and although it prob wont rev much past 6k, I am hoping for a fair what of bhp, plus a bit of nitrous. 500bhp would be nice. And before nayone goes off about RV8s and high power, I know, hence why I'm going down the forged pistons, rods, sump girdle route . . .
but so far I've fallen down at virtually every step of the way!
Posted: Thu Jul 03, 2008 6:36 pm
by CastleMGBV8
Ollie,
If I was you I'd just concentrate on the 3.9 engine you have at the moment. If put together properly it will make an easy and reliable relatively low boost 300+BHP motor with loads of torque, then you can get out and enjoy it, and perhaps give Perry a run for his money.
Any more power than that and I think you will need a better piston and something to hold the bottom end together.
Can't see the point of building a smaller engine even if you put loads of fancy bits in it.
Kevin.
Posted: Thu Jul 03, 2008 7:20 pm
by chodjinn
Well that's the thing really, I can't afford pistons etc for a 3.9 or larger. I was going to get a 4.6 block top-hat linered with standard internals, but I'd rather have forged pistons, even if it is a bit smaller capacity. There's not much difference between the 3.5 and 3.9, esp with the turbos. The new engine is more of a long term plan - buying parts for it as and when they come up because I can't afford a large payout at once. Plus there's a few 3.5 turbos I've seen running massive power with a lower spec that the one I'm planning hehe. My engine is pretty much done now, as is the rest of the car for the time being, but I will be changing the suspension etc. before building the next motor.
And besides, if I wait long enough a stroker crank might come up!
