3 replies to this topic

[Pavel]

Hi, I would like some advice from the turbo experts on the specs of an engine build i plan to do.

Due to change of plans, the 1275GT will be scrapped. However, I want to remove its engine, and rebuild it to high spec.

1293/1310/1380? Arguements for and against each please if possible. As far as I'm aware the difference in cost between them is neglibible.

What cam should I use? If power gains from higher-revving cams are great, then it'll do but ideally i want something more or less driveable..

Does an A series block suffice for such applications, or is the stronger A+ version more recommended?

Where and how much can i get some solid turbo pistons? I don't want forged omega jobbies, as this rebuild still has to have a sane cost, but i don't want AE Low comp pistons for 70 quid that will probably blow up after 2 miles.

I'll be trying to source a turbo manifold/carb/t3/plenum setup from UK as its getting extremely hard to find them around here.

The engine will probably have nitrous on it as well so keep that in mind.

Aiming for around 120 horses at the crank without nitrous.

I'll be running a metro radiator up front most probably. Bonnet can easily be vented for extra ventilation.

A gearbox will be rebuilt with a x-pin diff, central oil pick up.

Sorry if this is a bit vague, just want to do some research on this stuff before beginning the engine work and ordering parts etc.

[Turbo Phil]

Right .....
Basically most people avoid large overbore sizes where Turbos are concerned.
Increasing the capacity reduces the amount of metal between each cylinder & increases the chance of head gasket failure. Besides dispalcement is far less important for good power when a Turbo is employed. 1293 is all that's needed really, you can produce over 200hp with the right engine ......
Saying that i do know of somebody's who's run a 1380 Turbo for years with no probs, but i would stick to +.20

Omega do a good cast Turbo piston, as do Minispares.

You don't really need a very "racey" cam to produce good power figures, Piper phase 2 will be good for 160+hp & is road drivable, as is Kent 266 etc

120hp is not hard to achieve, and providing the engine is well built, will last for a long time. Basic cam, head mods and a small increase in boost will give you this.
Also worth adding is an intercooler.

Rebuild the standard gearbox "properly" fitting all new bearings twin pin diff and centre oil pickup and you'll have no bother.

What kind of hp are you looking for ?

Phil.

[Pavel]

Thanks a lot phil. Like I said, I'm hoping for over 120hp + nitrous.

I think I'll stick with the 1293. What head should I use therefore?

http://www.minispare...0/InvDetail.cfm Are those pistons okay?

[Pavel]

Avonbar have Hepolite Metro Turbo oversize pistons but only in 040, 020 are out of stock. They're quite well priced at 204 pounds too.

+040 = 1310cc, right?