206 replies to this topic

[retired308]

back in 1988 i had a chev offroad engine machined up it had
stock 308 crank all crack tested and balanced
l34 rods arp bolts
plus .30 trw forged pistons 10.5 to 1 comp
high energy pan
steel balancer
hei ignition
perry extractors single 3 inch with resonator only
bert jones 37-70 solid cam
torker manifold port matched
750 dp holley, blue pump holley
brookfield hand finished heads
rrockers 1.65 screw in studs l34 valves brown springs
very heavy steel flywheel -hv oil pump, 3core radiator, penrite oil 25w50
hand made clutch
toploader and 3.50 lsd 9 inch with steel hemisphere- 26 inch mickey t slicks it ran 12.7- went 13.0 on 13 inch circuit slicks
with a 60hp nitrous kit it went 11.715 at 117mph.
after getting a thrashing at the drags and driven everyday on the street a rebuild went like this-port matched exhaust-
hand finished dave baines a9l rods with 7/16 bolts-scattershield- redone hei system- 7/16 studs and new 7/16 rrockers-stock oilpump put in,
trw hand finished trw forged pistons- 2 holley blue pumps and 1/2 lines all thru, les heintz special clutch- 288 solid cam, flowed same red heads- with 4.56 gears went 12.4 then
the first run using nitrous killed the clutch on first attempt in c1990-91 at drags. tried to fix it but gave up racing after that.
john brookfield told me stock 308 had 140-160 hp, the l34 had 240 270 and the race cars l34s he did had around 340-360 in early 70s.
chev offroad thought mine had around 360 at flywheel plus 60hp nitrous kit added on. have some videos on vhs must find them all.

[Redslur]

Yep, love the old sckool stuff. I think 350 FWHP is pretty good out of a 308 especially in a Torana....

[ozyozyozy]

im keen to improve on my numbers, i want alloy heads, and if i get them comp is going to 11 to 1, and with that,want a cam change also to get some more rpm. dont want to do this unless we can make it relatively reliable. all the holden powered targa cars here are needing engine rebuilds at about the 4000km mark, dosent sound like much, there only getting used a few times a year, and when they do the poor engines are hurt.

[Redslur]

Alloy heads are a big improvement from what I have seen and experienced. A good cam to suit them will produce good power. Be interested to see how it goes for you...

[mr5000]

i havent had my car dynoed yet but the lil 308 slap job goes alright
red 308 standard bore flat top high comp pistons crow 5603 cam i think
red pre pollution heads and manifold all matchported at home slightly tweaked quaddy shitbag extractors with twin 2 1/4 system bosch hei dizzy with summit 6al style ignition

with the old banjo and the 13s it ran a best of 14.7 @98mph with heaps of wheel spin having open centre and 205s
plannign to get back to the track as soon as i get some big wheels now its got a 9 inch 3.5gears truetrac

had it thrown on the rollers today made 148rwkw would have liked more on the way home gave it a bit of stick and noticed it was pining at wot probably should have checked the timing before i put it on haha

[Struggler]

This is the first time I have seen this thread (was overseas all of Sept.)

Back in the day we would turn out heaps of flat top, HQ headed, standard stroke, Crane 286, Performer based combos. Depending on how much money you had you could also get big valves and roller rockers. Often we would rering the short, tidy up the standard valved heads, fit LT1 springs and a timing set, tweak the Q jet and slide in a 286 and these things would go really well for the minimal $$$ spent. People still remind me of these $1500 stormers today !

One of the 308's I built for myself back then used 327 lumpy top pistons and heavily cut heads. It ended up with almost 12:1 comp. The cam was a Crow grind, the same one Alan Grice used to set the top speed record at Mt Panarama in 1984. It was in my old Group C A9X when it was still road registered, 4.44 gears and a Super T10. Stuck with the Performer and an 850 Holley ! Well it had no torque at all and was hard to get going but once it got to about 4500rpm it would start to move and at 5500rpm it was singing ! Once they pulled the lead out of petrol it pinged like a demon and I had trouble keeping head gaskets in it. A customer ended up buying it (I have never heard a better sounding engine and it was the major selling point !) once I pulled the lumpy top pistons and fitted flat tops. I don't know where it ended up from there. I did have it on a chassis dyno but this was 18 odd years ago and I can't remember what it made. I do remember it was the highest HP from a stock stroke engine they had seen at the time. I later rebuilt the genuine L34 race engine that came with the car (it had a much smaller cam and flat tops) and it was a better mannered thing all round but had nowhere near the top end of the Grice combo.

These days I can't remember the last stoke stroke HQ 308 I did for a customer that wasn't a turbo engine. The cranks are so cheap and VN heads are everywhere. I beg those with VN heads to use a stroker crank to get the air flowing quicker.

The engine I did for my own VH SL/E is super low budget..... its a standard bore, dish top VP 304 short, honed, new rings and bearings. I used a pair of HQ heads that had the bowls throated by the machine shop and I blended them in by hand. Waggott 239 @ 050 single pattern solid, Performer and Q jet. The only new parts were the cam, lifters, gaskets, rings and bearings. Everything else was second hand. Exhaust is 1 5/8" tri Y and a single 2 1/2". Its a lot of fun with the T5 and sounds great but I haven't got it onto the dyno yet.

[Redslur]

Bout itme you posted up mate :-). Your experiences are always worthy of hearing!

Your first combo is similar to what I had before my current combo bar the flat top pistons and it produced 240RWHP. It really went well considering it was a totally stock bottom end. The new combo is just getting better and better as I get k's up on it. Can't wait to run it down the quarter. I now swear by the Crane 304 hydraulic, fantastic cam. The 286 was great too but no where near as much mid range power as the 304.

Hopefully others will continue to share their combos..

[ozyozyozy]

well, an update with my 308.
recently been having some oil pressure issue`s. started with oil surge, my light blinked at me during an event, then during cold starts pressure would go up and down, for about 30 secs to a minute, never done this before.
tried mucking around with everything i can externally to no succes, bugger.
pulled engine apart, main bearings have been hurt. we think, difficuilt to be 100% sure, oil pickup gasket is at fault.
also found oil pump drive gear, after 700kays is stuffed.
we`v tried both type of oil pump drive gears, coated steel and bronze, both crap. yes i no bronze you have to replace periodically, but to be half to 2/3rds worn after 700km`s, some of our events you travel 1000km`s in a weekend.
so after lots of talks alot of research im biting the bullet, dry sump it is.

[Redslur]

An update for those interested.

Took the hatch in for a dyno run today after upgrading my carby from a 670 to a 770 Holley to see what was happening. I gained 8 RWHP but the fuel mixtures were hugely too rich. Running around 10-11:1 air fuel ratio. Will have to get it properly jetted and should pick up another 10 or so RWHP. Ended up with 273.4 RWHP. Anyway it is nearly at its potential which is good news. The standard fuel system seems to be keeping up too.

Cheers, Gerry

[Struggler]

Hey Gerry, what dyno do you use ?

[Redslur]

^{It was done on a dyno dynamics one. Jake Sanderson owns it.
Dave at Gastune is re-jetting my hatch on his dyno tomorrow. His is an old school one. Will let you know what figurs I get off his too.}

Edited by Redslur, 24 January 2012 - 11:15 AM.

[Redslur]

Yep would have to agree with you V6 UC. From what I have heard several people that placed their car on the Summernats dyno this year said their figures were down a fair bit from the previous years Summernats. Just goes to show that they all seem to differ.

Unfortunately I didn't get dyno figures yesterday. I asked him for them too but he said most of the tunning needed was in the low to mid range and he only ran it to 4800rpm on his dyno. The car goes really well now and seems to rev a lot more freely. I will take it back to the place I got the figures checked orignally to see if it made any diference to overall figures. At the end of the day it is now runing at its potential and that was the aim and the stock fuel system seems to be keeping up.

[Redslur]

<sub>Sounds like 12's are quite possible with your set up.. Let us know how you go when you do run it down the quarter and also if you do get it dynoed.

I am taking my hatch back to be rechecked on the dyno this afternoon after having the carby proffesionally rejetted. Be interesting to see if it makes a difference to overall HP figures. I will be hopefully running mine down the quarter in the next 2 months.

Cheers, Gerry</sub>

[Redslur]

Took my car back for a dyno run and check this afternoon after having the carby rejetted. I ran it in both shootout and non shootout mode just to get a comaprison on figures. In non shootout mode it ran 272 RWHP and in shootout mode ran 281 RWHP, which is up 8 RWHP after jetting the carby. Pretty respectable figures form a fairly tame to drive non stroked 308.

The air fuel ratios are now spot on across the range running around 12.5:1 so the tuner did a top job. Anyone in Canberra after a good carby tuner I am happy to provide his details.

The car definitely goes harder now and since my fuel log upgrade and 3/8 fuel line mod from the fuel pump to the carby have seemed to sort out all fuel starvation proplems in the top end. I am a very happy camper.

Cheers, Gerry

[Redslur]

A mate of mine did film it and will send it to me. Knowing him he will chuck it up on Youtube anyway.

He ran his RT E49 replica at the same time. Managed 223 RWHP which is rerally good for a 6 pac...

[Redslur]

Nice set up. Any horse power figures? Should probably be similar to mine. I think the thing that will rob my car of a good quarter mile time is that the diff ratio is only 3:36.1.

[Struggler]

hi struggler just a quick question how do you avoid the valves hitting the lumpys ,im thinking about doing a similar combo

Valve to piston clearance wasn't a problem. I think I laid the lump back a bit to match the 308 valve angle but it wasn't too much.

Build it !