Jump to content

Question about MegaJolt - TPS or MAPS ?

Little Toe

Recommended Posts

Hi folk's,

I've recently acquired a V8, 3.5L that's on SU carbs at the moment. It originally came out of a RoverSD1 and I'm about to get it transplanted into my truck.

I'm thinking of going down the MegaJolt route so that the engine can run when wading.

Now for the question... I'm not sure where to go for the TPS or MAP options - can anyone advise on the pros and cons of each option?



Link to comment
Share on other sites

  • 2 weeks later...
I didnt drill anything - i just used the standard take off on the inlet manifold that the vacuum advance was previously connected to.



I tried mine like this and got it running ok. Then attached it like fridge has shown. The vac advance/retard take off gives a different map reading than direct to the plenum, I think it is not the right place to get map.

I am sure fridge will be able to comment with more knowledge than me.

Link to comment
Share on other sites

I've heard it said that the vac advance takeoff is a bit near the throttle butterfly and gets affected by turbulence or such like. On the RR (MS & Dizzy) I teed the dizzy feed into the same takeoff as my picture using a T connector in place of the elbow one.

Link to comment
Share on other sites

You need a take the MAP vacuum direct from the manifold not from the base of one of the carbs.

Some ignition systems take the vac for the dizzy from the carb base but the hole is either partially covered by the butterfly at tickover or is even the other side of the butterfly.

If there is a takeoff for the brake servo a tee into that would be fine.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy