Race Car, engine spluttering

Race Car, engine spluttering

Author
Discussion

TobyLaRohne

Original Poster:

5,713 posts

205 months

Sunday 21st September 2014
quotequote all
Hi guys, I've had this problem since I bought my car and I cant fingure out what is causeing this problem, if you click on the video and skip to 30 seconds in through to 1 minute you'll see the issue.

At first we thought it was fuel starvation but I'm not so sure, we replaced the fuel pump, the fuel cell is an ATL race tank with foam baffling and the pump sits in an anti-surge box.

In addition to this I've replaced the coil packs and plugs and injectors.

It only occurs when you're really pushing and generally only happen on a corner at high speed..or immediatly after a high speed corner, (note it never happens on the back straight)...

Any and all advice appreciated, I'm thinking about getting an fuel swirl pot and upgrading the pumps too but its very expensive so I'd like to check all other avenues first.

http://youtu.be/BrYo0o49koY

Edited by TobyLaRohne on Sunday 21st September 11:19

stevieturbo

17,229 posts

246 months

Sunday 21st September 2014
quotequote all
video doesnt work, and give details of the car.

And with a full tank of fuel and a good fuel cell, surge should never happen.

TobyLaRohne

Original Poster:

5,713 posts

205 months

Sunday 21st September 2014
quotequote all
stevieturbo said:
video doesnt work, and give details of the car.

And with a full tank of fuel and a good fuel cell, surge should never happen.
Ok so this was with a Honda Civic Type-R with a K20a NA engine in, stock internals, with a cold air intake and an exhaust manifold and race exhaust with a baffled oil sump.

The problem manifests itself even with the ATL 40l tank half full.

Note I run on semi-slicks.

PS. Link should be fixed now.

226bhp

10,203 posts

127 months

Sunday 21st September 2014
quotequote all
TobyLaRohne said:
Ok so this was with a Honda Civic Type-R with a K20a NA engine in, stock internals, with a cold air intake and an exhaust manifold and race exhaust with a baffled oil sump.

The problem manifests itself even with the ATL 40l tank half full.

Note I run on semi-slicks.

PS. Link should be fixed now.
What about with it full?
Check your pump is getting it's full voltage, if it is then doing a volume test is easy enough:
Remove fuel line from injector rail and put into a container, ign on and time how long it takes to put a litre in there.
Does that figure match what your pump should be giving?
If it does then is that enough fuel for the amount of BHP your engine is making?

anonymous-user

53 months

Sunday 21st September 2014
quotequote all
TobyLaRohne said:
Hi guys, I've had this problem since I bought my car and I cant fingure out what is causeing this problem, if you click on the video and skip to 30 seconds in through to 1 minute you'll see the issue.

At first we thought it was fuel starvation but I'm not so sure, we replaced the fuel pump, the fuel cell is an ATL race tank with foam baffling and the pump sits in an anti-surge box.

In addition to this I've replaced the coil packs and plugs and injectors.

It only occurs when you're really pushing and generally only happen on a corner at high speed..or immediatly after a high speed corner, (note it never happens on the back straight)...

Any and all advice appreciated, I'm thinking about getting an fuel swirl pot and upgrading the pumps too but its very expensive so I'd like to check all other avenues first.

http://youtu.be/BrYo0o49koY

Edited by TobyLaRohne on Sunday 21st September 11:19
At any point during what looks to be spending about £1000 to "fix" the problem, did you put a fuel pressure gauge on the rail to see if that might be the problem?? Bearing in mind you can buy a cheap mech gauge for about £15. Otherwise, feel free to keep guessing...........

TobyLaRohne

Original Poster:

5,713 posts

205 months

Sunday 21st September 2014
quotequote all
226bhp said:
What about with it full?
Check your pump is getting it's full voltage, if it is then doing a volume test is easy enough:
Remove fuel line from injector rail and put into a container, ign on and time how long it takes to put a litre in there.
Does that figure match what your pump should be giving?
If it does then is that enough fuel for the amount of BHP your engine is making?
I am afraid I can't confirm if it has done it before full, although I am sure it has done it at over 2/3rd I shall test it this weekend at the trackday and keep the tank brimmed to see if I can make it happen when its full.

I want to believe it is because its some wiring somewhere that is grounding out as its cheaper to fix than getting a swirl pot and pump setup. smile

Please if you're reading this and can make an educated guess what it might be, please chime in, any and all advice sought smile

TobyLaRohne

Original Poster:

5,713 posts

205 months

Sunday 21st September 2014
quotequote all
Max_Torque said:
At any point during what looks to be spending about £1000 to "fix" the problem, did you put a fuel pressure gauge on the rail to see if that might be the problem?? Bearing in mind you can buy a cheap mech gauge for about £15. Otherwise, feel free to keep guessing...........
The fuel pressure at the Fuel Pressure Regulator has been checked and is fine at idle or revving or on the dyno...however that isnt to say its fine in the corners at high speed, I've a bit of trouble reaching to look into the engine bay from the drivers seat you see hehe

I have a new Aeromotive FPR and gauge waiting to be installed in the next day or so as a precaution.

andyiley

9,105 posts

151 months

Sunday 21st September 2014
quotequote all
The time that it happens is 100% akin to fuel starvation due to surge in the tank.

According to what you say it shouldn't be, so do you know with absolute certainty that the baffles & anti surge tank are up to scratch?

Pumaracing

2,089 posts

206 months

Sunday 21st September 2014
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I don't mean to say nothing more constructive than "duh!" but it only happens on right handers and never on full throttle which means it could never have been the pump or injectors or anything else that can't possibly have been a limiting factor at part throttle so I have no idea why you changed those. It seems a simple case of the tank and pump baffle box just not working as you think they're meant to. Chances are the baffle box the pump is in is actually stopping enough fuel reaching the pump on right handers.

TobyLaRohne

Original Poster:

5,713 posts

205 months

Sunday 21st September 2014
quotequote all
Pumaracing said:
I don't mean to say nothing more constructive than "duh!" but it only happens on right handers and never on full throttle which means it could never have been the pump or injectors or anything else that can't possibly have been a limiting factor at part throttle so I have no idea why you changed those. It seems a simple case of the tank and pump baffle box just not working as you think they're meant to. Chances are the baffle box the pump is in is actually stopping enough fuel reaching the pump on right handers.
hey, no problem atall. It's happened on full throttle a few times. In the video I'm on full throttle both times it kicks in.

Steve_D

13,737 posts

257 months

Sunday 21st September 2014
quotequote all
Everything you say points to surge IMHO.
You say the pump is in a box. Is this inside the tank?
If so then replace that pump with a low pressure pump and install a separate surge tank with the High pressure pump below it.

Steve

Pumaracing

2,089 posts

206 months

Sunday 21st September 2014
quotequote all
I think you're misunderstanding the implications of full throttle. It may happen as you first hit full throttle at corner exit but that's only a symptom of the starvation through the corner. It doesn't do it on full throttle down the straight which means that all the pumping components can handle the maximum fuel demand when the surge is not happening.

stevieturbo

17,229 posts

246 months

Sunday 21st September 2014
quotequote all
TobyLaRohne said:
The fuel pressure at the Fuel Pressure Regulator has been checked and is fine at idle or revving or on the dyno...however that isnt to say its fine in the corners at high speed, I've a bit of trouble reaching to look into the engine bay from the drivers seat you see hehe

I have a new Aeromotive FPR and gauge waiting to be installed in the next day or so as a precaution.
Bit pointless sticking a mechanical gauge into the system to test for a problem...then not being able to see it when the problem actually occurs wink

That'd be like spending a fortune on a fancy fuel cell to fix a problem...when you're not actually sure what the problem is...

Wouldnt be hard to extend a bit of hose and stick the gauge to the windscreen for a quick safe visual test for only £10-15 in parts

Ideally you'd have an electric one with some way to log what's happening though

DVandrews

1,315 posts

282 months

Sunday 21st September 2014
quotequote all
Fit a surge tank.. Low pressure feed to it with overflow back to the tank pickup, feed the HPFP from the surge tank. Seen the same problem a number of times on race cars with stick tyres.

If you don't already have one of course.. smile

Dave

99hjhm

426 posts

185 months

Sunday 21st September 2014
quotequote all
DVandrews said:
Fit a surge tank.. Low pressure feed to it with overflow back to the tank pickup, feed the HPFP from the surge tank. Seen the same problem a number of times on race cars with stick tyres.

If you don't already have one of course.. smile

Dave
Seen this problem on many race cars slicks or not.

anonymous-user

53 months

Monday 22nd September 2014
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Before you spend any more money on guessing what parts need changing, actually use your brain to work out what is wrong, and then just fix that part!!

DaveL485

2,758 posts

196 months

Tuesday 23rd September 2014
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Agree with the above, very symptomatic of surge. My R21 did the same on hard-right corners until I fitted a swirl pot. Hard left was fine. Right? Splutter-splutter-go!