Section : General

General GT6 messages

MK II gt6 bonnet with a 2.5 ltr engine

Posted By : Alistair Mathie, 03-Oct-2004, 07:00pm

Hi,

i'm building a spit6; convertible gt6 (or whatever you want to call it!!) using a mk III spitfire body and a 2.5 Pi engine (still to decide if i'm using Pi or carbs). My question is :

does anybody know if a mk II gt6 bonnet fit over the top of a 2.5 engine without having to make any additional nasty buldges in the bonnet. I'd mcuh rather use this bonnet than a mk III gt6 as it will keep the same lines as the original mk III spit. I know that i'll need to make sure that i have the right chassis hinges for the bonnet i choose.

Any help appreciated.

Al

Followups :

MK II gt6 bonnet with a 2.5 ltr engine

Posted By : Michael Charlton, 04-Oct-2004, 00:27am

Should fit. Same block as the 1998cc just bored out i think.
- MK II gt6 bonnet with a 2.5 ltr engine
  
  Posted By : Nathan Gabbott, 04-Oct-2004, 09:17am
  
  I've got a Mk3 with 2.5 running PI.
  
  The sump is easily modified. The block and head are indeed the same but I think you know this. I guess you are interested as to wether the PI/carbs will fit.
  
  On the Mk 3 PI does fit however it is very close and I had to make a few mods to the airbox(I trimmed off the idle air feed and gave it its own minifilter(see photo). With this arrangment it still rubs on my bonnet liner at the front of the plenum. I think with the MkII bonnet this would probably be worse. You would probably need to find a way of dropping the plenum. Cutting and shutting the pipes could work or you could fab a new plenum up with minimal difficulty(I'm thinking of doing this myself to improve clearance and airflow over the log)
  
  Hope this helps
  
  Nathan
  
  MK II gt6 bonnet with a 2.5 ltr engine
  - MK II gt6 bonnet with a 2.5 ltr engine
    
    Posted By : Jonathan Binnington, 04-Oct-2004, 07:29pm
    
    it does go, just! see:
    http://www.supersix.50megs.com/ that's how I did it, with a little bulge in the bonnet to clear nos 1&2 injectors
    
    oh, and lots of other sqeezes to fit
    
    the PI system is a whole new ball game, imagine learning carburettors all over again...
    
    adds a whole new dimesion to Spit fire...
    
    binman
    - MK II gt6 bonnet with a 2.5 ltr engine
      
      Posted By : Alistair Mathie, 04-Oct-2004, 07:40pm
      
      Thanks guys, i'll keep you all posted as to how it goes.....i'm off to put in some new floors this weekend..............
      
      Al
MK II gt6 bonnet with a 2.5 ltr engine

Posted By : Adrian Lee, 04-Oct-2004, 03:25am

Not sure on GT6's,but on the Vitesse,the sump clearing the steering rack and still fitting under the bonnet is an issue.You may need too enlarge a 2 litre sump, with the "cut out" for the steering rack, for the longer stroke.Or modify the 2.5 sump to accept the rack ,check it out though ,things are tight enough under there as it is.

I'm sure one of the existing gitfire owners will know!
MK II gt6 bonnet with a 2.5 ltr engine

Posted By : David Rumens, 04-Oct-2004, 09:38pm

Yes it will. But you need the following.

GT6/Vitesse 2 Litre sump on which you need to dress indents in the steering rack step to enable the longer throw 2.5 crank to clear.

GT6/Vitesse back plate.

Front plate - Either saw off the front engine mounting brackets of fit a GT6/Vitesse front plate.

Fit the GT6/Vitesse front pulley and fan spacer.

Use the GT6/Vitesse flywheel.

Used the GT6/Vitesse engine mounting brackets and ensure the holes in the block have been tapped out to take the brackets bolts

Use the GT6 generator mounting brackets.

Use the GT6 thermostat housing top. The top hose inlet.

Use the GT6 exhaust manifold.
- MK II gt6 bonnet with a 2.5 ltr engine
  
  Posted By : Jonathan Binnington, 05-Oct-2004, 08:47pm
  
  Dave's preference is to use the GT6 'box
  
  my preference is to use one of the big TR boxes, either non-od or o/d with altered gearbox bracket.
  
  you will need to shorten the propshaft and alter the gearbox cover but after changing the gearbox 4 times on my 2litre mk1 i ceased to see the funny side of weak vitesse gearbox bearings...
  
  in which case keep the saloon/TR backplate
  
  binman
  - MK II gt6 bonnet with a 2.5 ltr engine
    
    Posted By : Alistair Mathie, 05-Oct-2004, 10:04pm
    
    Binman,
    
    thanks for this, i was originally looking to use the dolly 1850 box with a j type overdrive, but having done a bit of research i've decided to go for a 2500 saloon box with j type so that it will last. I've got a contact that will be able to build me a new prop.
    
    thanks for all your help so far, i've only just started the build and am focusing my time of getting the mk III body sorted.....it's amazing the botch jobs you find under years of underseal so its new floors, sills and rear wings all round......nitromors(?) and my angle grinder are my new best friends.
    
    Al
    - MK II gt6 bonnet with a 2.5 ltr engine
      
      Posted By : Adrian Lee, 05-Oct-2004, 10:18pm
      
      My best mate, A.Grinder, is absolutely loathed by me neighbours,yours will be soon.
      
      Try softening the underseal with white spirit first and see how much will scrape off before using nitromors.
      
      Good luck and enjoy
    - MK II gt6 bonnet with a 2.5 ltr engine
      
      Posted By : Jason Chinn, 06-Oct-2004, 08:06am
      
      I have a "custom" prop for TR type box to Vitesse diff sitting in the garage doing nothing - yours if you want it. I haven't paid much attention to it but it's been dry stored for years - expect it to need new UJs and a balance I'm staying with the sweet changing 3 rail and a J type so have replacement box and prop "in stock". The TR box is long gone. I live in Reading, contact me off list if you want it
      - propshafts for tr boxes
        
        Posted By : Jonathan Binnington, 06-Oct-2004, 06:04pm
        
        all, be advised the vitesse chassis is longer that the spit/gt6, the vit propshaft will still need shortening
        
        bin
        
        Propshafts For Tr Boxes
        
        Posted By : David Gable, 22-Apr-2006, 09:41pm
        
        My GT6 mk2 ran a 2Litre PI and the bonnet fitted ok, but a small dent appeared where pot number 1 injector was and the fitting had a small flat worn on the square edge.
        Also the distibuter centre lead from the coil sat against the bonnet. I also had the engine as low as I could get it. I remove the idle valve from the manifold and fitted a rubber tube between the valve and injector body. Removing it altogether, blocking off the hole and using the butterflies works but idle was not as precise. The 2 litre was much more revy. I was inspired at the time with the Gareth Thomas 2 litre vitesse with a limited slip diff and PI which was shod with 205x60x13 pirelli P6 or P7 Tyres.
        That touched 135mph in the vitesse brick through air.
        
        Propshafts For Tr Boxes
        
        Posted By : Jason Chinn, 22-Apr-2006, 10:36pm
        
        Dave - you been sleeping, that last reply too 2 years to post I've still gott hat prop!
        
        Propshafts For Tr Boxes
        
        Posted By : David Gable, 23-Apr-2006, 05:14pm
        
        Whoops, these late hours on the computer things become a blur, Anyway its good for reference for future members to attempt mods.