what performance can i expect?

[Wee_Watsi]

Dudes i know this has been talked about a million times before, but if i put a 1.3 sr head on the bottom end of a 1.2 carb engine, what performance can you expect from such a setup, and is it really worth it?

also for anyone who has done it before is there anything special i should no before i go out on this venture (anything special to b done or is it just a straight swap?) also what are common problems encountered with this setup?

this is my nova btw, wat do you think of it?

http://www.geocities.com/wee_watsi/40600031.JPG

[Adam]

Fitting a 1.3SR head would loose you power, 1.2 carb head is very good flowing.

You could fit a SR exhaust system(including manifold and downpipe), and a 1.3SR inlet manifold and twin choke carb.

Nova looks tidy btw, think the wheels would look better in white.

[Nova_Houch7]

Yeh nova is lookin good mate, like LLTN sed tho, wheels wud look better in white, altho gold is different i suppose..

If ur happy with it like that, then dnt worrk, jus dnt go chav style like u'll find in Muppet Corner thread names "Chav Nova?" lol

L

[Nova_Houch7]

Oh and clear side reeaters wud look beter IMO, orange ones look bit Shoddy

L

[Stuart]

*cough* less text typing houchy ;) *cough*


as said fitting a 1.3 head is a waste of time. might not lose pwoer but it wont gain you anything.

[rm7745]

1.2 head is the best designed head in the 8v 2JC engine series, and the 1300 head would lose you compression, but the 1300 cam will give you a few more BHP, as has a higher inlet lift as opposed to the 1200.

[Nova_Houch7]

*cough* less text typing houchy ;) *cough*

I am improving over time, cause im so used to using MSN all the time, but im getting there i think, ;) .

L

[Matt2107]

I have a set of tinted side repeaters and rear lenses ;)

I reckon the gold alloys look ok.. would look nice black as well though.
White shows up the dirt too much

[Nova_Houch7]

keep it clean then

L

[mikey14sr]

1.2 head is the best designed head in the 8v 2JC engine series, and the 1300 head would lose you compression, but the 1300 cam will give you a few more BHP, as has a higher inlet lift as opposed to the 1200.

I thought the sri head was best?????????

[Adam]

Sri head is best.

[rm7745]

haha, nope! look carefully at the inlet and outlet ports on the 1200 head and then the sri head, and if you have a keen eye and mechanical understanding, you will see what i mean! ;) ;) not including the 1300s mk1 astra head of course:D

[mikey14sr]

must be some big secret that none of the major head builders like blyndenstien have heard of? 1.2 and 1.3 heads have cathedral shape inlets, the sri 1.4 has big round ones, as an example, some of the guys on here have found up to 10bhp just from swapping from a b+ 1200 based head to a STANDARD 1400mpi head

[Adam]

Yep, the SRi is the best flowing, large round inlet ports, big valves(to make up for power losses because of the CAT on SRi engine)

Outlet ports are identical on all OHC engines.

[Stuart]

ive been over the heads with precision and has to be said that yes the 1200 head is fantastic but its not quite as good as the 1400 MPI head.

[rm7745]

Well what can i say?
whatever you wish to believe, just dont get next to me on the road thenm because you will be left behind!

i might just stick to migweb, seems like they know more!! hehe;) :D

[Stuart]

lol they dont nessecarably know more about the small block 8v's as those get thrown away by that lot ;)


i assume youve never had the heads on flow benches either? lol MEH you belive what you want and ill stick with what i see from real figures.

[rm7745]

do i hear a slight spark of intelligence???? hehe

[Stuart]

and how "modded" is your 1.2 ... and i dont care about neonz init :p

[rm7745]

shell looks pretty standard, but engine different!
its a 12st, twin 40 webers on imrscher manifold, 4 branch custom exhaust, block decked, 60 thou overbore, head skimmed (1200 hehe, sore point right now), a 284 deg ket cam kit, as prefer these to piper, have good gearbox, but it tto much for my engine really, it a f13, with wide ratio gears, and a 3.7 final drive on it, the diff is a gripper limited slip diff, works on a system similar to clutch pads, etc. all necesary stuff done to it

[rm7745]

fooking chavs give nova a bad name

[rm7745]

just got to wait until i got time to do my 20let front engine rear wheel drive conversion, with a dry sump, twin 50's, twin cams etc.

[Mike]

just got to wait until i got time to do my 20let front engine rear wheel drive conversion, with a dry sump, twin 50's, twin cams etc.

Why would you want to run a LET, with carbs???? Stick to injection!!! That way you can get an infamous "super duper chip" lmao

But no, id rather run a LET with injection tbh!! :thumb:

[rm7745]

for the pure reason that i have tried that type of thing before, and i dont trust electronic engine, i prefer old with raw power, no offence

[Stuart]

nice spec on the 1200... and i know full well how a gripper works thanks ;)
what kind of power is the 1200 chucking out? should give me atleast a number to hit as a minimum ;)

"dont trust electronics" lol it gives FAR better control over the engine than carbs ever can, especially on a FI engine.

[rm7745]

i know where you are all coming from with electronics, and i dont want to spark up an argument, ive seen them on here!! lol, its just what i prefer, just listening to the carbs, the air intake, and the everlasting adjustment on them! hehe, just me really
ive also had alot of trouble with the ecu breaking down under pressure

[Stuart]

im fairly sure you wont really hear much from the carbs when you have an IC and turbine in the way of the intake ;)