I don't know........ I had 250 pounders in my coupe first and it felt like a car with no suspension! I think the only damping or compression came from the tires! Most of the 510 Vintage race guys run 200-250 up front and the 1600 is a few hundred pounds heavier. I replaced mine with 175 pounders and it's still really firm, but at least it's got some compliance.

^^ Really???? I've got 250's in the front of my truck now and they definately don't feel noticably stiff when driving, in fact I thought about going stiffer :S

I don't know how people can run 225's etc in 1200's with ca18's and the likes, would be way to soft for my liking.

i tried 250's in the front of my b210, has a mazda piston engine in it, much heavier than the a12. way to stiff for me, mind i do have 280zx struts and inserts. went back to the 180 pounders, thou i would like to swap in a much stiffer roll bar

I run 8" free length 250lb front springs in mine with a 1" swaybar. The front end is really responsive but is way too stiff on the road to and from the track! This is with CA too.

Matching the rear end to suit is proving more difficult

OK everyone - I've just tried fitting kdfl-57s - and didn't - they are actually about 10-12mm shy of being 'captive' in a std 1200 coupe strut, meaning they are unroadworthy as is. I've contacted king, the option I asked about was the kdfl-17 which is basically the same rate as the 57 but longer extended length, and a similarly higher ride height. They informed me of another option - KHRL-115 - which should be even better, they are slightly lower than std ride height, but a long enough free length to be captive/safe, but beter still have a higher spring rate (the 57s or 17s are apparently 100 over 150, and the khrl-115s are 80 over 180. Very basically they are a progressive rate spring, that start out similar to stock (90lb/in) but once they compress about 1inch a coil or two come close to bottoming out, taking them out of the equation, and the rate goes up to 180.

SO they are still considerably soft compared to what people are running on competition cars, but close to double the rate of stock springs. I've had a lot of dramas with a local distributor (they took a good couple of months to get the springs delivered) so I'll let you know how I go as far as getting the khrl-115s as a changeover (the guy on king springs tech line was fantastic by the way, had all the info at hand, and indicated they had them in stock ready to ship if need be) and how quick they get them in. I'll let you guys know how they end up sitting/riding/handling when i get them on the darn car.

That sounds like the best of both worlds. Let us know how it works out, and what the ride height is with them installed.

i have 6 kgs hks springs with tokico pedigree S13 inserts, with a CA, worked well, wasn't a daily though

By the look of things, 200lbs will be a good start, I'm lucky in the sense that we have a shop that runs a exchange program on springs, for a marginal fee he will swop springs if it isn't what you need.

Mazda engine in a Datsun proves how deprived of good engines they are in the UK !!!!.

I hear they have plenty of good Mazda engines in the UK.