How far can an NA engine be taken?

[hudson701]

OK I'm at the stage now where all the standard breathing mods have been done and am wondering what to do next. The car is really lumpy and could do with a remap aswell. Ideally I'd like to get up into the 160 - 180bhp region.

If I stay NA what sort of power gains could be had and what is recommended? Cams & remap or throttle bodies - what are the advantages/disadvantages?

The idea of supercharging appeals to me - is it really as simple as bolting on a supercharger kit from GMC?

What I really want to do is build on the mods already done - not remove the 4-2-1 and replace with a turbo manifold, for example. Build upon whats already there rather than completely change direction.

I'd be interested to hear what other people have done when they reached the same crossroads I am at now.

Discuss!

[gouldy87]

if its running lumpy, is it already cammed? ive got all breathing mods and newmans ph3 cams and im very happy with how mine performs, needs a remap though really to gain the most from the cams etc... i wont be taking mine any further tbh im very happy with it

[hudson701]

Its quite lumpy - but only on idle. It sometimes cuts out on idling. I wonder that adding all the breathing mods without a remap will always cause the engine to sound lumpy.

[gouldy87]

no mate it will idle fine with breathing mods. me thinks its either got cams in already or your idle speed control valve, MAP sensor or manifold pressure sensor or your lamdas sensors may need replacing. recommend a diagnostics check and if it comes back all clear i would take it there matey. i had the same problem with mine after having the manifold fitted my car would not idle properly, turned out it was both lambda sensors that were shot hope this helps mate

[Ryan]

an NA 16vcan be taken to 200 if you have deep pockets

see my threads of a bodied and high spec car in the E garage and on track at brands

[Xsi16v_Jk]

Saxo s1600 rally car,
220bhp - YummmY

[Toad]

Weren't they nearer the 230 - 235bhp mark?

[AXracing]

The super 1600 cars were even heavily restricted including rpm caps and inlet chokes so plenty more is possible without these.

The biggest problem is the gearbox. Without a suitable gearbox you just end up throwing cash away with engine tuning. If you cant keep your engine in its power band what is the point. You are far better spending the cash on the box rather then the engine.

The one thing to remember is that the more you tune a engine the stresses are involved. You will have to service the car a lot more regularly and it will have a much shorter life. Race cars will have oil changes every race and constant engine rebuilds. Your talking engines that last not in there hundreds of thousands or even tends of thousands of miles but rather hundreds of miles.

[williamsvts]

your wanting to keep NA? but your talking about supercharging and turboing it?

[Toad]

Did you sell that box were talking about a while back Ax?

[AXracing]

Did you sell that box were talking about a while back Ax?

sorry to say Toad I have sold them all now. I'm totally sold up on all my Saxo and Pug parts. Though if your after any bike bits I have them coming out my ears :wacko:

[Toad]

Ha! No, no bike bits required. :) Really want a proper gearbox...

[landanimal]

isnt the gearbox out of the xsara picasso a good gearbox? could someone give me info on that box as im interested in getting a new box and i heard that one is quite good.

[Ryan]

BE4R box in the picasso iirc.

BE with TU bell housing, BE boxes have alot more ratios to play with than the MA range.

toad iirc one of the boxes ax racing sold was the one that rossie had and now lewis has.

I can vouch for oil changes, my NA engine needs them often, the oil is fecking bleeeeeck after short periods of time.

[Toad]

I still want one... :)

[saxova]

best gearbox for a vtr?

[hudson701]

your wanting to keep NA? but your talking about supercharging and turboing it?

No, just throwing ideas around at the moment.

What sort of gains can be expected from throttle bodies? Would a remap be needed?

[Ryan]

a whole new ecu is wanted with bodies, not just a remap.

the whole point of bodies is to allow you to maintain equal airflow to each cylinder with mad cams

[Sparco_Tom]

and what a difference a good set up of cams and bodies make :) thats your best bet mate

[landanimal]

so what would be the best BE box to go for? i dont know alot about this? i was thinking about just geting the box out of a picasso and fit it and be on my way?

[Ryan]

there is no best ratios, as depends on the spec of engine and what you want from it.

[Shak]

is the picasso box a straight swap?

[Ryan]

nope as it used BE shafts so need new hubs etc..

[vtr-tec]

the BE box requires either psf mounts or custom made ones as it mounts in a different way.
also the hubs have to be shortened and the hubs adapted. easily a lot of money there 1k plus tbh when you have found one with good ratios and decide on a diff plus labour your up to 2k :D

I intend to work on the transmission this year ready to have a strong engine next year. Prior planning ;)

[Ryan]

dean who has one on his 106 recons its not as expensive as people talk about.

he keeps trying to get me to go BE on mine

[hudson701]

and what a difference a good set up of cams and bodies make :) thats your best bet mate


Talking mega bucks then is it?

Would it be cheaper, or the same sort of price to go the supercharger route?

The kits on gmc seem very attractive in comparison