Would anyone be so kind to offer some advice ?

[Mr400]

I really have no idea what cr to go for and what can be managed by aftermarket computer on pump fuel. I have looked at some cams and not sure what rev range is a good balance. I don't expect to drive it alot though that said once driving it I expect I will wish to drive it all the time. I would like to see it peak 8500-9000rpm, though this narrows the power band to around the 4000-4500rpm up. That's a decent stalley and then not sure if the box will handle this very well, the thought of a manual has been in my head though a lot of cost for what. I am also not sure how strong the stock diffs are. I have no problem changing the centre out to a higher ratio with lsd, killing a little off the top end won't matter to much. I could really do with some advice on the cr and revs using pump fuel.

 

[rx7 s1 1uz]

what will help with estimating a good safe rev limit and cr, you may wont to list a few more things that contribute to it e.g.

you are going 2 be using ross pistons from the group buy on now

are you using standard valves, springs and retainers or what:

are you getting head work/porting:

what conrods will you be using:

 

[Mr400]

Sorry rx7, you are correct.
I had actually posted this same question before with more details though ignored (in the piston group buy, trying to determin the cr). Yes am looking to buy the Ross pistons hence the question on compression ratio. I also intend on using Argo rods, 8 ITB's, extractors, some mild head work and likely larger valves. Aftermarket computer to control it all though not sure which as yet which brand. Not sure about the strength of the box or diff, most likely will change the diff out for a higher ratio lsd. If the box can handle it will choose to leave it and add cooler and stalley, maybe manual valve body ?

 

[rms]

I think you should lower your sights a little, 8500/9000 will blow your budget big time.
For an engine with a 3500-8000 rpm range you will not get any change from $18,000 and most of that is parts and outside machining.

Pistons - unless you have special one off pistons made you are stuck with Ross 10.5-1.

Argo rods are OK but a little on the heavy side for 9000 rpm

ITB's - you will need the A1turbos NZ manifold and Toyota ITB's, you are wasting your time if you use the Lexus lower half manifold.

Camshafts/valve springs - many cams available with upgraded springs. You will have to convert to shim under cam buckets. The aluminium standard bucket collapses under the shim with higher spring pressure.
With higher than std lift the valve guides need to be shortened as well as the stem seals.

Heads - with oversize valves the valve relief in the Ross piston needs to be enlarged.

 

[rx7 s1 1uz]

i think u will need to up grade your valve springs and retainers to something like this http://cgi.ebay.com/ebaymotors/Toyo...ryZ33621QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
i will be asking them if they can sell a set of 32, they are very good value also
and also lower your rpm range maybe more like 8000 rpm

Sorry rx7, you are correct.
I had actually posted this same question before with more details though ignored (in the piston group buy, trying to determin the cr). Yes am looking to buy the Ross pistons hence the question on compression ratio. I also intend on using Argo rods, 8 ITB's, extractors, some mild head work and likely larger valves. Aftermarket computer to control it all though not sure which as yet which brand. Not sure about the strength of the box or diff, most likely will change the diff out for a higher ratio lsd. If the box can handle it will choose to leave it and add cooler and stalley, maybe manual valve body ?

 

[nissan-lover]

I really have no idea what cr to go for and what can be managed by aftermarket computer on pump fuel. I have looked at some cams and not sure what rev range is a good balance. I don't expect to drive it alot though that said once driving it I expect I will wish to drive it all the time. I would like to see it peak 8500-9000rpm, though this narrows the power band to around the 4000-4500rpm up. That's a decent stalley and then not sure if the box will handle this very well, the thought of a manual has been in my head though a lot of cost for what. I am also not sure how strong the stock diffs are. I have no problem changing the centre out to a higher ratio with lsd, killing a little off the top end won't matter to much. I could really do with some advice on the cr and revs using pump fuel.

Every engine responds a little bit differently to tuning, but 11.5:1 with custom pistons and a careful tune is normally doable, 12:1 needs a lot of attention to detail on the tuning and will knock on stale tanks of fuel, but has been made to work, some of the honda guys are at 12.5:1 and pump gas, but that takes a lot of dyno time to keep it together.

Mike