SR head differences - 1300/1400?

[Stanley]

ive heard about putting a 1300SR head on a 1400SR to raise compression.

is this just a straight swap?

manifolds etc the same?

what kind of gains are expected?

cheers all

[Lee-1984]

i know the 1.3 sr head has got better flow then a 1.4

[Adam]

Inlet manifold is different.

Ye, the head has much bigger ports and flows a lot better.
Should add a few bhp.

You will need an inlet off a 1300.

Everything else will fit.

This pic shows you the difference in port shape. ;)
1.4sr left, 1.3sr right
http://img.photobucket.com/albums/v86/Nova-crew/1400left-1300right.jpg

[mad-driver]

This pic shows you the difference in port shape. ;)



And size lmao! So glad i put the 1300 on mine

[matt1chelski]

The 1400 isnt much faster is it?

[Adam]

Around the same, that shows how poor and inlet and head is, the 1400 has a better cam and 100cc bigger capacity, yet only makes 2bhp more than the 1300.

[Stanley]

so ideally stick the 1400 cam in the 1300 and put it on that way?

what kinda gain would i be looking at?

what about 1200SPi head?

[Adam]

Burn the 1200spi head. lol

Yeah, fit a 1400 SR cam if you have one, probably wont gain too much, only about 0.12mm lift extra.

You should fit a 1300 head,1300 inlet,1400sr cam.
Probably be around the 80bhp mark.
And you could always fit a weber 32/34 to the 1300 inlet in the future.

[mad-driver]

spi head nooooooooo! lol

Apparently the best option is buy a 1400, and stick a 1300 head on it, as it will raise compression nicely...

Funnily enough thats what i did:D

[Stanley]

im running a 1400SR at the moment so i already have the cam.

anyone on here actually done this before?

any other ideas on this? extra advice?

[mad-driver]

What Ad said, swap the 1400 head for a 1300, or 1200 even, with an inlet to suit, and maybe a 32/34 weber, makes a good difference i had this setup before i got my twin carbs. The exhaust manifolds are the same so that doesn't matter.

Obviously a highlift cam is best, but i think the 1400 SR one has the best lift as std

[coochiSR]

i was asked to get all the dimensions (someone at work decided to tell me im stooopind and it will never make a good difference) but i disagree, what difference does it make, pulling off, top end?

[Adam]

More flow through the inlet and head, so more power out.

[coochiSR]

ok cool! thanks for all your help mate, will ahve to look into it then, probs get it ported and polished first:) so its better pulling away?