What size are trumpet base bolts?

[dbv8]

As the title.
I need to get a new set longer as i am fitting a 12mm tufnol spacer under my trumpet base to provide clearance for my new direct port nitrous injecors from the fuel rail.

Can anyone confirm they are hex head and give me an approximate length please.
My mate has the inlet manifold and can check the thread size and get some bolts for me.

Edited by dbv8 on Monday 24th January 16:13

[clive f]

they are cap heads, allen key type bolts, can`t remember the thread though, pretty sure its an imperial size.

Edited by clive f on Monday 24th January 16:23

[spend]

3" long 5/16"UNC OTOMH?

[Alexdaredevilz]

dbv8 said:

i am fitting a 12mm tufnol spacer under my trumpet base to provide clearance for my new direct port nitrous injecors from the fuel rail.

Got any pics?

[dbv8]

Will be much nicer when all finished properly i promise....

[clive f]

that gets me all tingly in my nether regions

[dbv8]

A lot of experimentation, trial and error.
The odd step backwards.

As you can see the first set up was with a single injector in the elbow, then added another (because i had one) to help with distribution a little.

Then i fitted 2 more injectors to spray to the roof of the plenum on an independent second stage.

The 8 injectors in the trumpet base (ie direct port) is this years experiment. I will be getting a new pair of solenoids to run this so in effect could run a 3 stage set up.

I aim to use a progressively controlled 200 shot on the direct port set up for on track use only (honest).
The elbow injectors will have a 'mild' 60 shot on the push of a button.
The plenum injectors are for when i get greedy.

According to a certain expert in these matters my forged pistons etc should be able to handle a huge amount of nitrous. The weak link in the engine will be the head gaskets.

I have fitted raceproved driveshafts and an uprated JE clutch so the gearbox is the weak link in the drivetrain but ive ran out of funds!

[spend]

You didn't do much weight saving...


...the trumpets still look just like LR sold them

[Alexdaredevilz]

Looks good,

But isn't that abit over kill? I mean you already got one per port, how can more be of any use? surly if you wanted more you could upjet the port jets??

Sorry if im talking out my ass

Alex

[spend]

Thats hot air cooling is everything?

[dbv8]

spend said:

You didn't do much weight saving...


...the trumpets still look just like LR sold them

That trumpet base with the 8 injectors fitted was donated by a fellow TVR owner.
I had to force £20 into his hand.

My trumpets are the ACT bellmouth type although i am thinking of pulling the standard trumpets out and blending.

[dbv8]

Alexdaredevilz said:

Looks good,

But isn't that abit over kill? I mean you already got one per port, how can more be of any use? surly if you wanted more you could upjet the port jets??

Sorry if im talking out my ass

Alex

Yes you are right, but i also want a system for on the road and i dont want to be using a system jetted for 200 bhp or more.
I will have a seperate bottle plumbed into a 60 bhp system at the elbow for the odd overtaking procedure.

[roysum]

Like it !!

[Alexdaredevilz]

dbv8 said:

Alexdaredevilz said:

Looks good,

But isn't that abit over kill? I mean you already got one per port, how can more be of any use? surly if you wanted more you could upjet the port jets??

Sorry if im talking out my ass

Alex

Yes you are right, but i also want a system for on the road and i dont want to be using a system jetted for 200 bhp or more.
I will have a seperate bottle plumbed into a 60 bhp system at the elbow for the odd overtaking procedure.

I reckon you should sell me your road system, your being greedy
Alex

[haircutmike]

Just putting mine together, it's a bonding process!



Should be on the road this weekend !

Derek, you will need an imperial allen key when you source the bolts.

Edited by haircutmike on Tuesday 25th January 11:00

[350Matt]

dbv8 said:

spend said:

You didn't do much weight saving...


...the trumpets still look just like LR sold them

That trumpet base with the 8 injectors fitted was donated by a fellow TVR owner.
I had to force £20 into his hand.

My trumpets are the ACT bellmouth type although i am thinking of pulling the standard trumpets out and blending.

as you've added 20mm to the intake length this is probably a good idea as you get a good gain by shortening the standard trumpets by 25mm in any case plus the middle 4 are pretty close to the plenum roof which restricts them a bit

[dbv8]

My inlet manifold is at a nuclear power station! and has been shotblast clean and the mating surfaces skimmed.

It seems stupid to stick a standard bore inlet and trumpet base onto nicely ported heads.
Ive just had a word with my mate and he is going to get the inlets machined opened to 45mm. I will then open up the rest of the ports with a burr (etc) and also open them up to match my heads.

I will give him the trumpet base for similar treatment next week.

[TVRleigh_BBWR]

You could get the base milled down so it ends up the same height.

[dbv8]

TVRleigh_BBWR said:

You could get the base milled down so it ends up the same height.

This is the problem.
I have need to raise the base with a 12mm spacer so that the fitted nitrous injectors clear the fuel rail. See the pics above.
I also have a 12mm spacer for the plenum but guess i wont be able to refit this as i may have issues with the bonnet! I will try first tho

[roysum]

Why don't you get your mate to fabricate a nice reduced height sheet ally plenum, you can stick a nice big throttle body on it at the same time. I'm sure we can cope with another 1p on our energy bills FFS !!