19 replies to this topic

[TerrA LX]

going ahead with a V8 UC and wondering what heads to start with.
will be used daily and once every two weeks at the drags.

[TerrA LX]

I will be going through the same exercise very soon now.

UC Dragster with a Turbo pattern 308, 40th over - running a TH 350. Why? I hear you ask.. because it's what I have sitting around in the shed. Actually to be honest I have these items stored at a friends place lol.

Mine will be a dedicated drag car so it will be interesting to see what recommendations are made here engine wise.
It will be a lower end of the budget build up and hopefully giving somewhere around a 12 second pass, I figure any faster will cost me dollars I don't have nor could probably get without a major engine sponsor.

I will be keenly watching this thread.

Cheers
Herne

so you went with the 308 block because it was there or did you put it aside for this project.
i will be looking at 13 seconds.

Edited by ALX76, 10 June 2006 - 12:57 PM.

[Struggler]

If you only have a target of 13's then use a 308 with HQ heads. Heads, manifolds, extractors etc are all cheaper and easier to find. They will also make more torque at low speeds and be more fuel efficient.

JMHO

[TerrA LX]

13 sec is not the target, 11 sec would be gr8t but this car must have kids etc in it, also driving to work, picking up mum, going to the shop etc etc. its a second car not a third.
so the faster the better but must have impecable manners.
anyway i was more concitering starting with the heads and going from there.
block selection is unimportant at this stage.

Edited by ALX76, 10 June 2006 - 02:55 PM.

[makka]

go with HQ heads

[gtrboyy]

I would be going for a set of vn heads with a dual plane manifold to start with for a carby set up but I reckon an injection set up would be even better as it would make more power than a b cast head & have nice street manners as well.I love the vs s3 5l injection on my lc as it has a reasonable amount of power & just about anyone with common sense can drive it to.If you really want the car to be streetable,run 12s then I would be looking at a stroker,then vn heads but in the end it all comes down to budget which is why most just go to a vn injection set up.

[TerrA LX]

go with HQ heads

chev or holden.
any suggestions on valve sizes or spring instaled height/pressure.

[TerrA LX]

I would be going for a set of vn heads with a dual plane manifold to start with for a carby set up but I reckon an injection set up would be even better as it would make more power than a b cast head & have nice street manners as well.I love the vs s3 5l injection on my lc as it has a reasonable amount of power & just about anyone with common sense can drive it to.If you really want the car to be streetable,run 12s then I would be looking at a stroker,then vn heads but in the end it all comes down to budget which is why most just go to a vn injection set up.

VN heads sound good but most peep seem to dump the injection.
what difference will a stroker make to choosing heads.

[makka]

well you cant fit chev heads on a holden engine, so assuming you are planning on fitting a holden V8 in it the chev heads would be useless.

maybe you should try Cleveland heads on it.......

[gtrboyy]

With a stroker you will have more torque which means that you can use a smaller torque converter & taller gears making the car more streetable especially if you want it to be dual purpose whereas if you want to make the same kind of power with a 308 you will need a bigger cam,bigger stall,shorter gears & rev it harder than if you had a stroker engine.If you plan to drive it daily & race occasionally a stroker would be more suitable than trying to do it with a 5l,especially if you want to do 12s & keep it streetable.

[TerrA LX]

well you cant fit chev heads on a holden engine, so assuming you are planning on fitting a holden V8 in it the chev heads would be useless.

maybe you should try Cleveland heads on it.......

sorry, you assumed i was starting with a block. no motor yet.
i was told the best place to start a build was with a set of heads.

[TerrA LX]

With a stroker you will have more torque which means that you can use a smaller torque converter & taller gears making the car more streetable especially if you want it to be dual purpose whereas if you want to make the same kind of power with a 308 you will need a bigger cam,bigger stall,shorter gears & rev it harder than if you had a stroker engine.If you plan to drive it daily & race occasionally a stroker would be more suitable than trying to do it with a 5l,especially if you want to do 12s & keep it streetable.

to save money then should i run a chev.

[TerrA LX]

I think you are perhaps going about this the wrong way.  It would be best to set out some sort of paramiters that will determine type of motor etc you will need rather than picking heads out of thin air.

So we have a 12 second aim in a very streetable package, which is a good start. 

What sort of budget are we talking about here, because that will have a big influence in what you should choose.

How much work are you also willing to carry out, because that will determine chev or holden.  Is there any more work to installing a chev in a UC than installing a 308?  If the work required is pretty similar then a chev could be a better bet because of its larger capacity.

All this sort of information will help people to offer better, more specific advice.

Peace,

budget will be around $5500. instalation and labour (besides machine work) are not to be included.
would i be better off choosing a block or complete motor first, then a cam shaft and heads to suit.

Edited by ALX76, 10 June 2006 - 07:08 PM.

[Struggler]

OK lets back up a bit...... what do you have now, beside a UC body ? Changing to a Chev means different radiator, exhaust, starter etc.

Don't be offended but 5.5K will not go too far toward a streetable 12 sec combo. It would be easy to spend that on a diff, gearbox and convertor capable of reliable 12's. I am not trying to put you off, just letting you know how it is. I have run 12's in a daily driver but I was willing to put up with welded banjo diffs and slippery convertors. Would you be prepared to carry spare axles and change them on the side of the road with your wife and kids ? I didn't think so. It isn't all about the engine, its the whole combo, and if you want it as a daily driver it has to hang together as well, particularly if you are carting the family around.

[TerrA LX]

forget about the car for a minute, $5500. is for motor only.
i am trying to select the best heads and build my combination from that.
i dont have a motor, i dont have a gear box and i dont have a diff.
this is a project, i havent rushed out to buy anything yet.
just looking for advise on were to start, with the most suitable heads or the most suitable bottom end that will give me enough torque in a 1250kg car to compete at the drags, change the tyres and the next day drop the kids off at school then off to work.
there is no set quarter time, i just mentioned 12's be nice, wouldnt be ashamed if ill be pullen 13's.

[TerrA LX]

,Jun 10 2006, 09:39 PM] Not sure on the legislation where you are regarding small block Chev's into Torries, but if its allowed then a 350 will be under less stress than a 308 would be to make the same power...

late crate motor no probs for pollution but engineers for cubes at 350 as only allowed 40% cube increase 202 at 40% equalls 282.8 so same goes for 308.