Page 1 of 1

My 2.5 TD performance upgrades

Posted: Wed Apr 18, 2018 7:05 pm
by Merlot man
Hello all
I've been looking at upping the performance of the bongo for a while now and started by looking at these topics on the site if your interested they are really worth a good read
https://igmaynard.co.uk/bongo/forum/vie ... 12&t=71556

https://igmaynard.co.uk/bongo/forum/vie ... er#p559446
The steps I've taken myself are
1 . I completely removed the EGR system from the exhaust manifold to the intake manifold and blanked off both ends using a plate on the inlet and a plumbing blank on the exhaust this helps keep the inlet temps down
2. Then I got both manifolds port matched and smoothed on the inside to improve the flow of air going in and the gases going out and to the turbo , this helped a lot with smoother pick up and the bus to be more " eager" to go , I got this done by a member on here who really knows his bongos , rustyp , he did it on an exchange basis and did a great job I must say . I'm hoping that he will come on and explanation better what he can do !
3 . I replaced the inter cooler with a larger one and positioned it on the front just behind the bumper and as low as possible to avoid the cooling rad . I'll post a link to the supplier if I can find it again but basically I got one that was not very tall but as long as the bumper space would allow , this required some inter cooler plumbing which you can easily source for the same supplier . As I was at it I replaced al the inter cooler sealing clips with mikador type items .
4 . I get a thermal gasket and a thermal plate made up for both manifolds to help reduce heat in the inlet charge and to Keflavik heat out of the chamber , I got these fron ferriday thermal products link below

http://www.ferriday.co.uk/thermal-products/
5. I insulated the piping going into the inlet manifold using thermal tape you can source this from Amazon or similar , I'll try and find a link .

Overall I really feel that the bus is running smoother quieter and is faster ( at least fast for a 24 year old bongo ) it now doesn't die nearly as much as it did going up hill =D>
Russ ( rustyp) was a fantactic help both with his work on the manifolds and for all his advice
One thing I tried to do but failed was to tighten up the turbo waste gate actuator by shimming out the mounting bracket as I could not get the bolts to come off ........Any ideas ? [-o<
I have some photos of this but of course can't post them but if your interested I can email them go you
I hope this is of some use to all you "power hungry " TD pilots !
Any other tips would be greatly appreciated
Brian

Re: My 2.5 TD performance upgrades

Posted: Thu Apr 26, 2018 11:05 pm
by rustyp
Thanks Brian :D with the inlet manifold I smoothed out the lumps and bumps from the elbow that goes round the camcover into the manifold. For the inlet manifold itself I opened out the entry, cleaned up any castings inside and then opened out all 8 manifold runners to match the head as they are much smaller than the ports in the head.

The main performance gain I think is reworking the exhaust manifold as there are a lot of ridges that are disruptive to exhaust flow which I remove and I open out where the exhaust gases exit into the turbo as it is very narrow as standard.

I then coat the inside of the exhaust manifold with a heat reflective coating and also I make expansion slots on the flange where it bolts to the head, both of which help stop the manifold from warping.

On my present and previous Bongos I have ported the heads to good effect as well :D

Re: My 2.5 TD performance upgrades

Posted: Fri Apr 27, 2018 10:15 am
by Merlot man
Thanks for getting posting Russ and making explaining it all to us !
I may very well get the head reworked at some stage as I really feel the benefits of all your other work , I really think thsat this work is well worth doing to make the old bus more drivable
thanks =D>
Brian

Re: My 2.5 TD performance upgrades

Posted: Sat Apr 28, 2018 2:07 pm
by Billybongo123
Next thing, up the boost pressure