Looking for more power!

[Zac]

I’ve been searching for some time now for way of increasing the power output from my V6 3.0lit. It seems that the main problem according to articles I’ve read on the net is that although the 3.0lit engine potentially has lots of power to offer, you will never unleash all of it all the time it being choked off by the existing restrictive exhaust manifolds. It seems that the ultimate and most effective modification is to exchange the manifolds for a pair if headers and the Downey ceramic ones seem to be the best. I’ve recently read an article on Yotatech written by a guy who has done the conversion and it seems that it’s a real pig of a job to do and not one that should be attempted by the faint hearted.

Has anyone out there fitted headers and if so was it as bad a job as it seems to be?

I’ve also been told that more power can be got from re-mapping the ECU. Has anybody had this done and did it add any power?

PS I’ve already done the K&N drop in replacement filter thing and that did make a noticeable difference, although not as much as I would have liked.

[TonyN]

After market headers are a big plus, BUT, you need 2" body lift to clear the pipes, plus anything built in the US won't clear a right hand drive set up, as the headers need to be a different shape to avoid the steering column.

The trouble is, the left hand bank of cylinders exhaust just goes around the back of the block, and then joins the right side and then down to the exhaust system, with a restrictive cat in it.

I found things got really hot under the bonnet on my pickup with headers, way more than with manifolds plus the twin pipes under the floor heated up the cab a lot.

You won't get huge gains without intake mods like a straight intake pipe and cone filter to match the exhaust, then fueling issues (injectors and ecu) to match the free flowing intake and exhaust.

Better off just fitting a Nos kit!

[Guest]

After market headers are a big plus, BUT, you need 2" body lift to clear the pipes, plus anything built in the US won't clear a right hand drive set up, as the headers need to be a different shape to avoid the steering column.

The trouble is, the left hand bank of cylinders exhaust just goes around the back of the block, and then joins the right side and then down to the exhaust system, with a restrictive cat in it.

I found things got really hot under the bonnet on my pickup with headers, way more than with manifolds plus the twin pipes under the floor heated up the cab a lot.

You won't get huge gains without intake mods like a straight intake pipe and cone filter to match the exhaust, then fueling issues (injectors and ecu) to match the free flowing intake and exhaust.

Better off just fitting a Nos kit!

How about the deckplate mod on the airfilter housing - seems to be a favorite way to release a bit more power.

You may be able to get some headers custom built by someone like John Woolfe Racing.

Cheers

[TonyN]

How about the deckplate mod on the airfilter housing - seems to be a favorite way to release a bit more power.

You may be able to get some headers custom built by someone like John Woolfe Racing.

Cheers

Yeah, forgot about that.

You'd still need a body lift I reckon, the offside manifolds go behind the block because there simply isn't room for them down that side of the block due to the steering column. Custom made is the best option, but they'll be a bugger to get in.

I'd leave the headers till last, you don't want high under bonnet temps on a petrol motor, especially with a cone filter that gets alot of air from inside the engine bay or the deck plate mod, get a decent cat back system, ditch the cat, and play with the intake.

[Guest]

Yeah, forgot about that.

You'd still need a body lift I reckon, the offside manifolds go behind the block because there simply isn't room for them down that side of the block due to the steering column. Custom made is the best option, but they'll be a bugger to get in.

I'd leave the headers till last, you don't want high under bonnet temps on a petrol motor, especially with a cone filter that gets alot of air from inside the engine bay or the deck plate mod, get a decent cat back system, ditch the cat, and play with the intake.

Could also get the shape relieved on the existing manifolds and polish the throats. OK you won't get the advantage of equal length that you get on headers however it may help them to work a bit better.

Also a downside of headers is that they sometimes give you more top end power at the expense of flexibility.

I agree with Tony that a good quoality exhaust system, cat back, deck plate mod and even some work on the cylinder heads (porting and smoothing) may well add as much power as a set of headers anyhow at a fraction of the pain.

Cheers

[rusty]

Yeah, forgot about that.

You'd still need a body lift I reckon, the offside manifolds go behind the block because there simply isn't room for them down that side of the block due to the steering column. Custom made is the best option, but they'll be a bugger to get in.

I'd leave the headers till last, you don't want high under bonnet temps on a petrol motor, especially with a cone filter that gets alot of air from inside the engine bay or the deck plate mod, get a decent cat back system, ditch the cat, and play with the intake.

HA, been there, still playing with it. I have changed the plugs to Iridium types have changed the air filter (standard one though - I don't like the increase in induction noise of the K&N's etc) I have had a stainless exhaust system fitted and de-catted it. It's better than it was before (less MPG though : ) but there is a definate improvement in the mid range. I have done the air pipe mod but am waiting to fit it. If you really want to improve performance you could look at resituating the Air Flow Meter to right against the Inlet manifold then pipe your K&N from that. You would get an improvement in throttle response (hopefully)

[Zac]

Thanks Tony. The issue of US manufactured headers not fitting a R/H drive is obvious when you think about it but something I’d completely missed. Also the issue of raising the temperature under the bonnet is a good point. Even with the possibly of being able to get a pair custom made, given the difficulty of fitting them plus the heat issue and the likelihood that other mod’s may have to be done, it sounds as though this is a road I’d rather not start down.

The deck plate suggestion made by lucky is interesting. I’ve read about this being done befeor and it sounds as though this is less destructive than peppering the bottom of the air box with holes. Does anyone know if there’s someone who produces a kit or is it a DIY job.

Cat Back???? Can anyone explain what a cat back system is as the term is a new one on me.

What about ECU mapping, is this an option?

[dirtydog]

A 'CAT BACK' system just means the exhaust system from the Cat (catalytic converter), Back (i.e. till it exits the car). Usually is just middle pipe/rear silencer but sometime people take the Cat out but not sure if this is advisable on a Surf as I dont have one.
Tim

[Oji]

More power?

An auto electronics place in Barking (E London) once told me they could probably get at least a 10% power increase simply by fiddling with the ECU. I can't remember the name of the place but they were in River Road just off the A13.

Also, I once saw a supercharger kit for V6 engines in the Longo Toyota website - www.longotoyota.com. Longo are part of the Penske empire, situated in El Monte just east of LA and are the biggest Toyota dealer in the world - 3000 cars always in stock! Their website is very useful for getting an idea of parts prices and when I have been there, they have had even quite obscure parts in stock - the sort of thing that would probably take you 6 weeks to get hold of in the UK.