New Zealand Datsun Club

Hey guys need some advice, i just dynoed my car on friday, it made about 65 kw at the wheels and about 100 nm torque now its a factory 1600 block rebuilt and the head is a w53 with 2 mm oversized valves, 40 thou taken off to raise comp ratio to about 9.2 to 1, stage 3 franklin cam (287 degree duration) and uprated double valve springs, cam timing set to 110 degrees (106 recommended) headers and full 2 inch exhaust system, twin 40mm dellortos tuned by myself ( 13.5 to 14 to 1 afr) with k and n filters and lastly running an msd splitfire cdi unit (uses points to trigger but no current through them) now personally i am a little disappointed with the numbers of kw i ran and want more so whats your opinions on whether to do more headwork or to do a 60 thou bored over l18 block with my head? Any ideas or inputs welcome.

Been down this road before.
Ferrol Errol from RatDats in Melbourne always told me that measuring dyno figures between dynos is fraught with danger. There are just so many variables even down to which gear the car is dynoed at and then there are rolling roads, dyno packs etc.Ambient temperature as well as engine temperature has a huge amount of influence.
Let me ask you this- seat of the pants, how does it feel/go? Because if you are happy then unless you are racing it don't worry about it.Also did you check out mixtures or play with the timing? Good gains to be had in the fine tuning rather than worrying about an overall figure that really is so 'wishy washy' it doesn't mean an aweful lot.
Cheers
Dave

b110sss wrote:Been down this road before.
Ferrol Errol from RatDats in Melbourne always told me that measuring dyno figures between dynos is fraught with danger. There are just so many variables even down to which gear the car is dynoed at and then there are rolling roads, dyno packs etc.Ambient temperature as well as engine temperature has a huge amount of influence.
Let me ask you this- seat of the pants, how does it feel/go? Because if you are happy then unless you are racing it don't worry about it.Also did you check out mixtures or play with the timing? Good gains to be had in the fine tuning rather than worrying about an overall figure that really is so 'wishy washy' it doesn't mean an aweful lot.
Cheers
Dave

Well firstly i reckon it goes amazingly like really good but always want more power haha, as for playing we didht really mixtures cz i had Wideband attached to it and all were going good in good range as for ignition timing we never played but now maybe i wonder? So you think leave as is? Cz id love a bit more power so hehce why i thought the 1800 block

If you think it goes really hard then chances are it does, but if you want more power cause your not happy with a dyno reading then id advise you to observe daves post, I personally see a dyno as a tuning tool, any gain made on the dyno will benefit you on the road for sure ,

I'd just take it to Ruapuna drags and see what time and speed you do. The weight-shifted time/speed will tell you how much power is reaching the rear wheels, assuming you also know its weight (a weighbridge will tell you).

65RWKW suggests around 125hp at the engine. That is quite good for a 1600 I'd say.

I had an L20B in a 1600 that ran 16.3 secs on the 1600 SSS SU carbs, proving that the SU's could flow enough air for a 16sec quarter.

denpal wrote:I'd just take it to Ruapuna drags and see what time and speed you do. The weight-shifted time/speed will tell you how much power is reaching the rear wheels, assuming you also know its weight (a weighbridge will tell you).

65RWKW suggests around 125hp at the engine. That is quite good for a 1600 I'd say.

I had an L20B in a 1600 that ran 16.3 secs on the 1600 SSS SU carbs, proving that the SU's could flow enough air for a 16sec quarter.

How do you get 125 hp at engine just curious? And spose i shud run her at a drags and seecwhat time it does.

65 divided by 0.78 for 22% driveline losses (ie 100% less 22% = 78%), divided by 0.67 factor for KW to HP. The numbers aren't exact but it's close enough.

denpal wrote:65 divided by 0.78 for 22% driveline losses (ie 100% less 22% = 78%), divided by 0.67 factor for KW to HP. The numbers aren't exact but it's close enough.

This is a cool way to look at it makes me feel a little better i dont know why but i just feel like i want more as stupidcas that sounds, realistic gains do you think an l18 block swap would be beneficial?

More cubic capacity of course is a good thing. The torque and hp gain L16>L18 would be roughly proportional to the increase in capacity all other things being equal and assuming it wouldn't be then under-carburetted etc.

The L20B block is 19.6mm taller (think bonnet clearance) but otherwise a simple upgrade and this can be expanded to 2300cc, see this from Troy Ermish:


L-Series 2300cc

$3,800.00 for engine+ $300.00 Core fee. L-series 2300cc - 89mm bore, 92mm stroke. Engine comes with: new pistons, reconditioned rods, ARP rod bolts, new rings and bearings, new timing set, new oil pump, open chamber u60/7 cylinder head, 44mm intake valves, after market valve springs, reconditioned rocker arms, 520 lift cam, all new gaskets and freeze plugs. Port work and race dampner is extra please call for more details. 510.252.1001 Engine pictured is not the one for sale. Dyno @ approx 200hp & 200 ft torque! Dyno sheets available. This is a long block price, all accessories need to be providing by customer ie: dist, oil pan, V-cover, carbs, header etc. CA Pays Sales tax, Shipping and handling not included 510-252-1001

I almost bought this Ermish engine but then decided to stay with the original L16 in my 1600, given how original the car is. The freight cost was $250 from California to NZ. This build will give you 200hp FWHP, or about 105RWKW. Troy is a highly respected US West Coast Datsun race-car builder.

I have 2 spare engines at home but want to stay close to the l16 for originalities sake, whats your guys thoughts on an L17? I have a spare 1600 block that is running an 1800 crank and 1600 pistons and rods making a 1688cc which not too much bigger than my engine should not be undercarbed and should give me a reasonable increase in power and torque? I will put my head on from my engine.