hey fellas i'm currently finishing off my 25/30 silvia i will post in members rides the specs on the car once completed.i am having trouble deciding wether to cut the bonnet and put an xr8 bulge over the top or something along those lines or is there a bonnet that i could buy that will fit my engine underneath has anyone done this and knows wat will fit any help will be appreciated cheers..

What crossmember did u use?

Could buy one of the uras style vents and cut it to cover up the top of the cam cover! I think that would be the easiest/cheapest option!

do you need it to be street legal?

Ive seen a few RB powered silvias and none of them have had bonnet issues, i didint actually think the engine has a higher total height than an SR... Its not exactly an uncommon conversion.

i would go the hole in the bonnet to let people no wwats goin on under the hood
unless you want it to be a bit of a sleepa

Bulge looks a bit horrible IMO.

All depends on which crossmember they use as to how low it will sit. Mounted height IS higher than sr20.

i would like to keep it a bit sleeper..........until i stand on it haha. but i also would like to keep it legal. i used a c33 laurel crossmember on it, before wen i had the rb25 in it, it just rubbed on the bonnet heatshielding but because of the extra deck height of 38mm on the rb30 block it now hits the bonnet. i will have a look at the uras vents cheers for the comments and ideas keep them coming!!

What touches the bonnet? the front of the cam covers or the cross pipe?

talk to this guy?
http://www.boostcruising.com/forums/index....howtopic=457065

Yer because that guy hasn't modified his bonnet at all.

like i said - most of them dont have to modify the bonnet, ive never seen anyone have to do that.
Id look at using a different crossmember or modifying the engine mounts to get it sitting lower. Will save you chopping bonnets, and also give you a lower centre of gravity. Big iron block at the front of an S13? id be getting it as low as possible.

Lil Bobby: Are you talking about RB's in general? As far as I know the rb30 cross breads are a much taller motor.

Not sure you know what your talking about mate.

exactly
find out what he has done
then do the exact opposite?

Just stfu, lol.

i dunno, OP is asking about cutting the bonnet and adding a bulge, not making it fit without any mods

Still trying to get over the 'Research proven workable solutions then do the complete opposite"

you guys fail.
lol..


30/25 will sit an inch taller than a 25. end of story. it's a bigger motor.

you want to fix your issue. lower the motor, dunce. get a smaller engine mount. not hard.

to add, you can also use a R33 xmember which will sit it a little bit lower again.
but smaller engine mounts are the go. VERY simple.

ive decided i am going to cut the bonnet after all after seeing another person with a similiar problem,and no i cannot use a different cross member or different engine mounts because i have a greddy plenum which hits the clutch slave cylinder so thanks for the help but i am goin 2 chop and fibre glass a bulge i will put a members rides post up once i have finished car.cheers fellas!

I know exactly what im talking about. You can fit RB30DE's in them without modifying bonnets. thats all im saying, its been done before, and ive seen it with my own eyes, which is a bit of a stronger statement than you saying 'as far as i know'.

I dont know what im talking about? WHAT IS A CROSS BREAD, MATE?

Just cos my opinion is different to yours, doesnt mean i dont know what im talking about.

OT - if its not going to be registered, nothing beats the look of piping and cam covers through ur bonnet to show youve obviously got something far from standard under there. If its gotta be on the street, id go for the XR8 bonnet bulge as it will be by far the cheapest and smoothest option.

EDIT - aftermarket plenum and such causing clearance issues eh? well there you go.

I think he got the oppinion about you not knowing what your talking about by all the 'advice' you give out about nearly everything in the drifting section with very little 'drift' car setup/seat time drifting....

Many people do fit them in without modifying bonnets, but as he has said, pretty much use any (offshelf) aftermarket inlet and you cant just lower it down without hitting, hence 95% of 30 bottom ended skylines/s13s run some form of vent to cover it as its much easier to change bonnets than it is to relocate the clutch slave..

^^^

Also who excatly wants their engine sitting lower to the ground? Aftermarket sumps aren't cheap and will generally hang lower than the stock sump anyway. Not really keen on having my sump as the lowest point of my car...

that's one way of seeing it although a lower centre of gravity especially when putting a bigger heavier motor in the car is handy although not required

Yeah fair call but thats when bash plates come into play!! Cheap and simple to make!! or buy!

+1.... I've got a 33 crossmember with landrover engine mounts, my 25 clears the bonnet by inches,
Gay xr8 bulge = Fail

yer i wasnt keen on ruining the stock cosmetic lines of my silvia but i found an alternative option east coast customs make a buldged bonet thats adr aproved so thats wat i have decided on doing cheers for your inputs...........skids4kids

Use an A32 Nissan Maxima clutch master cylinder and the plenum will fit.
As buckna said, R33 cross member and smaller engine mounts.