Hello all

Looking through some books, I've noticed some books list the 308/5litre V8 being 5047cc, from HT-HX era, after that listed as 5044cc.
I'm lead to believe its 5044cc up till the VK 304 came out.

Whats right and wrong?

.. interesting topic Damo.

VK 304 engine is specc'd at 4987cc (per various GMH tech, service and engineering bulletins I have from the time of release)
and that engine has FIA homologation at 4987cc
but
the same engine in VL (carby and PFI version) is 4983cc according to the Holden service and engineering info I have
and VN EFI engine info also states 4983cc

what happened to the 4cc??

Yes, you see these small errors all the time, as Byron said "rounding errors".

AFAIK they reduced the stroke by 0.040" (from 3.0625" to 3.0225").

Dr Terry

haha... maybe, figures can lie and liars can go figure!

GMH hedged their bets... from the Improved Performance engine manual, engine details -
stroke is
3.057" to 3.067" .. or 3.062" being halfway or 77.648mm to 77.901 (or 77.775mm average)
but
VK Grp A SS manual for that A9L engine is 40thou or 1.01mm less at 3.020 to 3.028" but is 40thou less 3.0225"?

the VL Grp A SS (both carby and PFI) states stroke is 76.708 to 76.962mm (76.835 average).. note no imperial measures now.
and
with that info, 77.775 to 76.835 is not 1mm says my calculator!

but in final confusion, GMH signed the FIA homologation forms for the later (smaller ) V8 with its capacity stated on the 1st page as
... 4980.8cc

Edited by user Monday, 17 April 2023 6:06:01 PM(UTC)  | Reason: Not specified

I remember back in the old days with the 308's people would put Chev 327 pistons in the 308's. reason why was because the Stock 308 piston was not as strong and when one had hotted up with bigger camshaft they would use this piston as nothing other was around but to go down this track, but the 327 piston sat to low down in the bore, i think 0.040 ? lower than the Stock Holden piston.

So reading this about what they did to make it the 4.9L crank ? could they do the same the other way and make a stock bore 308 become a 312ci and + 0.060 = 320ci. and use the 327 pistons as they will be at a good height in the bore then ? as 327 pistons sit way to low for good performance.

I can not remember the compression ratio of a stock 327 in a 308 comes to, as it's a flat top piston.
Not to mention if a 327 was sitting 0.040 higher maybe around 10.5:1 ? not bad with a big cam !

But then again one could stroke the std crank to what you wanted within it's limits ?

I don't recall ppl putting in Chev pistons in 308s because they were stronger than the Holden version...

they went in because you could get FORGED Chev versions with DIFFERENT PIN heights that you did not have to sell a kidney or your children for
.. you would have trouble getting something like that for a 308 40 years ago. Nowadays is much better... I stipulate what piston I want in my race engines
always forged (after I broke an original hyper set) and I can get them in what ever height I want, for whatever ring set and whether with reliefs or flatops


latest set .... SRP these are

Totally agree, the engine badge numbers are often not even close to the actual precise number of cubic inches.

There are several that are "off" by more than just being rounded. The 400ci Ford V8 seen in the early 70s LTDs etc. are actually 402ci. The Ford marketting guys probably thought that 400 was a nicer looking number than 402.

A Holden 202 is actually 201.25, but again 202 probably looks nicer & sounds better than 201.

The 308/5044/5047 thing is even worse with the 253 V8. The badge is 253 which converts to 4146cc (closer to 4.1 litres) is actually 252.85 ci which is 4143.7cc. Even closer to 4.1 litres.

Dr Terry

Edited by user Tuesday, 5 March 2024 2:13:14 PM(UTC)  | Reason: Not specified

next...?

lets talk about factory hp ratings

Holden's 173 is 2.850L on the badge !

When a engine comes close to something like 2850cc then they called it a 2.850L. if it was on the lower range under 2850cc it was called a 2.8L and if it was on the higher range of 2850cc they called it a 2.9L.

Look at Holden 202 and fords 200 6 cyl, why, marketing comes into it ? because many people are dumb ? and would think that the engine is the same engine ? and then comes the 3.3L both are 3.3L but just as the Chev Gen 3 is called a 5.7L many people claimed this was a 350 chev engine but it's not 350ci at all.
So this dude i know claimed that they used the old 350 pistons from the Iron cast 350 blocks and that is why they used oil ? I said not at all, because you can not fit a 350 piston into a Gen 3 bore in fact regardless ! because the Gen 3 has a smaller bore !

Another pain was the Ford Windsor 302 and the Windsor 351 ? because the 351 Cleveland is a 351 as well and people can mistake such off the bat ! and then Australia made the 302 Cleveland to make more mistakes possible when talking or looking up figures regarding such things.

I had some people think my HG 253 Premier was a 327 Chev engine, why because i dragged them off ! and they mistaken the oil filler breather as a Chev thing, but they were on all Holden V8's from HT-G in fact. even to this day some think i am having them on, that it was only a 253, because it was from take off neck and neck with a XC 5.8L with stock dual exhaust to 112MPH my HG only had a single 2 1/4 in exhaust with free flowing muffler and that picks up the performance well on a stock 253.

Then again when talking about engines in cars, one can talk about what is a reasonable price to fork out just to get the engine performing better ? Like option a new VB-C-H-K-L Commodore V8 to get the dual exhaust, the DIN Figures do not lie !

The we could talk about head work and Camshaft spec that are with in the range of a stock engine but liven it up well ! nothing to do with becoming a hot rod rocket ship at all, just truly sensible mods that a 90yo could drive even and no lose of torque down low ! and not many people talk about such a thing. because such talk in the main goes off with the pixies on high performance rubbish with some one using 6000 RPM to 7000 RPM with good power at that rev range ! no one wants that unless you are being a rat bag on the road ? and yes i do like such a rat bag engine and to fang such a thing but i am not on about such now ! only within the limits of a good stock range with no lumpy cam, that no one can pick that you have a full on done your home work and came up with a stock type of engine that will blow the doors of what was original spec engine setup ! I would let people drive my 308 P Van and they were totally blown away, saying f she goes ! what the f ! that's a freak motor, etc.

I had a dude come up to me who had bought my HQ 202 98.000 miles up on it never been touched ! and only a 2 in exhaust and a good reasonable quiet muffler, that's what did the trick ! but i seen people fut on a smaller exhaust than standard, why, because such was a cheaper option, they had no idea or could not care less.

no...
GMH stopped painting them blue one day and started painting them black*... there was a breakpoint and bingo all were black from then on.

didn't really matter as a VH 5.0 was the same engine black in VK (until some of the hipo specials appeared... A9L, V7X etc)

If the engine number if not there, being decked... yeah a bit of a problem
unless you are expert, you cannot tell the difference between a normal VT, VA, VB, VG or VJ numbered engine,
VC coded is easy as they are RED being the A9L 'Grp A' engine but the others???

The VT numbered engine won't have the better inlet manifold (used on VA, VB VG engines) and even having an EGR
valve is no help. ALL VJ engines (auto and manual) had them but they are not on VB and VG coded 'manual' engines.

WB exhaust manifolds differed from Commodore .. but who has the original exhaust on it these days?

Ignition distributors did help when blue V8s were introduced as auto manual and 253/308s all got differing
coloured paint dots (the GMH manual tells you which belongs on what engine) but now... do you have the original dizzy?



*I have ignored those painted silver for the various series of Bedfords that were fitted with Holden V8s
(low comp with 2BBL carbs they were)

Edited by user Thursday, 21 March 2024 8:32:20 AM(UTC)  | Reason: Not specified