what are the engine differences between the rs16i and the 3i. thinking about building a n/a cvh track car and wondering how well the 3i engine responds to tuning compared to the rs. im aware the rs is worth a small fortune so buying one as a track slag is unreal;istic but can a cvh be built to a similar spec without a btcc budget?

 

Different shaped valve throats in the head

Solid lifters

Different profile cam shaft

3i has dizzy, 16i has a mapped spark signalled via the sensor lead and flywheel sensor

Better exhaust manifold

 

if starting from scratch you might as well take a normal 1.6 cvh and mod that

Headwork will have to be done and that will remove the intrinsic value of the 16i head anyway

Check this out

http://www.gomog.com/allmorgan/cvh.html

 

Much better off installing a 1.8/2.0 zetec ( or a 2.0 duratec ) in a mk3/4 and tuning that, much easier and better\cheaper rewards

 

There's nothing better about a RS1600i head to any 1600 cvh head of that period.

In all fairness, there's nothing trick or worthwhile about the RS1600i engine whatsoever that should encourage you to start with that engine. It is for all intents and purposes a std 1600cvh with a solid lifter cam fitted. (Yes I know it has unique anciliaries but they're only special if you're keeping the RS1600i car as an original car)

My recommendation is get yourself a late XR3i hemi engine (i.e. 86 - 89) and modify that. Usual route would be big valve ported head, solid lifter cam, set of throttle bodies, decent 4/1 exhaust manifold, H section con-rods, set of forged pistons and around 12:1 C.R. Good for 160bhp. Happy days!

 

so the round fluted exhaust ports are of no benefit to the standard more 'tunnel shaped' xr3i ones?

(obviously if having head worked then not an issue but as standard the 16i head IS better)

Off topic, can we have some pics and an update on your gorgeous 3 door?

 

No there is no benefit whatsoever to the slight machine work done on the exhaust port exit. Firstly it is only the very exit that has had a circular taper on it to essentially diverge the D shaped port into a circular exit, the throat and seat area are std cvh in profile. This machining op was done to all CVH engines in that period that used a round exhaust manifold port, not just the RS1600i. It is however of no benefit to power whatsoever.

 

i had a feeling internally they'd be little in it, been that the cvh is somewhat generic. just thought been an rs it would have some clever porting/hot cam and larger valves ect since its qouted hp is reasonable for an n/a cvh. the brooklyn car footage on pootube got me thinking, they sound kin ace.