108 replies to this topic

[mr5000]

take it to the track and see what it runs i rember a mate of mide had a barge ass vq statesman wiuth a 5litre only made 165kw but had mountains of torque think his best run was a 13 flat in something as small as an lc torry you might pull a good time straight up

[rexy]

No, no, no too much. If you are paying the money you should get what you pay for. Old school red heads on a Torana up to 300RWHP running 12 easy. VN heads start with 250 300RWHP and go hard. Or you may as well slap it together your self. I would be pist at this.
Dyno’s are a bit misleading maybe 10 or 20 hp but if you have 300 or 400HP it must be in the ballpark. Chassis dyno or eng dyon the air fuel ratio should be set ok still.
Some people use dyno figures to brag and other are disappointed.
Sorry for the disappointment but a little bit of home work and you can achieve this yourself. So an eng builder should do a lot batter than you or me, street manners and power.
If you are going to VN heads you want power, I think you can get better than this pretty easy, SORY.

Got to love everyones belief in giant easy dyno horsepower.
Those of you old enough might remember the early days of the summernats dyno comp where 500hp at the treads from a supercharged holden was the big stick. In the same era Chris Simpson (I think?) won the aspirated big block comp with 430 odd hp at the tyres.
Mark Hayes valiant took a couple of runs and tweaks to get to 600 hp with the big block blown mopar on methanol.
I simply do not believe a lot of the numbers thrown about, particularly when they involve cars that dont come close to running the MPH to prove their power.
Yours in scepticism.

[rexy]

Blonde moment. It was of course Mark Arblasters val WAR 440.

[ACJ]

XTREME Holden’s volume 9 page 90 VN head 383 LX Torana 10.3 @ 129 mph (look very street able) 520 HP eng dyno
XTREME Holden’s volume 11 page 68 VN head 355 LH Torana 10.9 @ 124mph (look very street able)512 HP eng dyno
XTREME Holden’s volume 25 page 28 VN head 355 LH Torana 11.6 @ 119mph (look very street able) 362 RWHP
Do the math’s, Torana 10.9 ¼ = HP ?? must be up there near 500 HP ?
I looked at all these cars parts list and more. All seem to have VN heads T/P or harrip manifold and crane 288 cam is very popular. Put my together and got 404 RWHP.
Even with a smaller cam ryan_525 should get 300/350 WRHP.
If it was mine I would take the manifold off and look at the ports in the heads to see if they have had the bump removed where the push rod go through and especial if he has a T/P manifold they have a very small outlet which must be open up to mach his heads. If the VN heads still have the bump it is the weak link in the chain not much better than red heads.

Edited by ACJ, 04 December 2011 - 11:50 AM.

[rexy]

Those numbers when put into a basic power speed calculator show:
Case 1 has 467 hp by mph, 504 hp by et
Case 2 has 415 hp by mph, 425 hp by et
Case 3 has 366 hp by mph, 353 hp by et
All figures are for approx flywheel horsepower.
I assumed these were not stripped out racecars either with approx race weight with driver of 2750lb.
With the same assumed weight you need 319 flywheel hp to run 11.99
In the slightly lighter LC/LJ (assumed 2640lb) only 307 flywheel hp are required.
So no, you dont need 500hp to run a ten in a square torana.

Lots of happy dynos out there. Makes it hard for the honest guys when their clients say "but my buddys 308 made 500 at the tyres why cant you make mine the same? You must be a spaz."
Of course the client then goes to the crook who is quite happy to take his money and give him a sheet with a bigger number on it.
We call love big numbers. Many of them sadly are not legit.

[TerrA LX]

What's a google?

[jason365]

All figures are for approx flywheel horsepower.
I assumed these were not stripped out racecars either with approx race weight with driver of 2750lb.

Sorry but I think you're a bit off on you're weights there, my stripped out hatchback hillclimb car with fibreglass doors, b/bars bonnet,lexan windows no trim , 1 lightweight seat no heaters alloy 9" centre muncie 4speed and a bunch of other weight savings tips the scales at 2760 lb with half a tank a fuel and driver ready to run.that's on very accurate longacre corner weight scales not the local weigh bridge.
Not ragging on ya but the slide rule is only as accurate as the figure you put in.a typical street strip lh lx torry with 9" th350 big wheels and tyres trans coolers, performance fuel systems and all the other crap needed to go hard will tip the scales somewhere between 2975 to 3050lb

[jason365]

hi LXSS350, i weigh around 85-87 with my race suit, boots, helmet and gloves depending on how many pies ive had, the car had 25 lt or approx 1/2 tank of fuel so around 20 kg. so that would put the car under 1150 dry.still running iron heads so when i step up to my TK prepped dash 3s ill drop another 20 or so right of the nose then i may wsh to balance it out by going a fibreglass hatch, that will definetly be it for that car, my next hatch will run all alloy engine, not sure if gen 3 or a/m rodeck early type chev, thinner lexan windows, more fibreglass panels, fuel cell ect, the weight limit for sports sedan is 1150 and i know i can get one down to around that, any extra will be a bonus meaning ill be adding weight where its needed to tune the chassis.

[myss427]

That is light, I have an all alloy big block and anything that was heavy is aluminum. fibre glass bumpers, light weight seats, alloy 9 inch and mine comes in at 1350 for a road car. You have done well to get it to that level!

Edited by myss427, 06 December 2011 - 03:17 PM.