5 GT Turbo EFI - GT Turbo

[DaveL485]

let alone in an untested, paddle clutched, side exit 5.

Hand in your Man Card at the door on your way out!

 

[Mark Davis]

Hand in your Man Card at the door on your way out!

New date Sunday 20th Nov.

 

[TNT Andy]

Hand in your Man Card at the door on your way out!

LOL - you can be such a turkey at times.

 

[DaveL485]

LOL - you can be such a turkey at times.

I've earned my stripes bruv, 'Ring and back three times, Alps tour, La Chatre, and god knows where else in a stripped out bare 21 with a one box 3" exhaust, two huge fuel pumps on the rear bench and a screamer pipe.

I carry earplugs in the car.

 

[TNT Andy]

I've earned my stripes bruv, 'Ring and back three times, Alps tour, La Chatre, and god knows where else in a stripped out bare 21 with a one box 3" exhaust, two huge fuel pumps on the rear bench and a screamer pipe.

I carry earplugs in the car.

And. ...........

 

[Mark Davis]

Off to get mapped tomorrow at 3pm, driving it there and back so let's hope no issues, I've got breakdown cover just in case.

Will update when I can.

 

[Adey]

Good stuff. I see some man pills have been taken if your driving it? Good luck bud will have to swing past for a passenger ride at some point

 

[Mark Davis]

Haha yeah mate, haven't really got a choice but sure it will be ok.

Come by and drive it mate, no bother.

 

[Clarkey]

Off to get mapped tomorrow at 3pm

Good luck, look forward to seeing the results Mark.

 

[Brigsy]

Good luck and get some videos whilst mapping

 

[Mark Davis]

Didn't get any vids, was too busy scratching my head and watching Chris straightening push rods.

As many have seen on Facebook, it made 240hp/229lbft at 27psi. Not what I was after but it is what it is. Will get to new cam and turbo combo next winter but for now I just want to use it.

We stopped at 27psi due to bending push rod closest to water pump. Could probably of gone a few more pounds but Chris suggested we would get closer to knock.

The only unknown on mine now is cam, unsure what make or what it's dialled in at. So instead of chasing figures I'll use it properly.

Top graph is standard head at 25psi, bottom is today at 27psi.

 

[andybond]

I suppose that is a bit of a dissapointement for you. For me I wouldnt get hung up on peak figures. All the fun is under the graph anyway

 

[Mark Davis]

Yeah was expecting more but all good fun nonetheless, had a good day.

Will get some good use out of it now.

 

[Clarkey]

Gutted you didn't get the results after all the effort put in.

Welcome to my world of bending pushrods same cylinder too, no.8. Any witness marks on the head?
Seems to be our issue, the rods hitting head. Will be opening the pushrod holes when we strip engine down.
Did Chris have any thoughts regarding the pushrods? You didn't have any issues before, which is strange.
We bent a couple there when we run the VNT, it spiked to 30psi.

 

[Mark Davis]

We didn't investigate further with the pushrod David, we were done at that point so Chris straightened it out to get me home.

I've not been able to investigate further. It happened on the third run at 27psi but took numerous runs between 23-25psi. I'm going to dial it back to 25 and just use it and hopefully they won't bend.

 

[Clarkey]

You did loads of runs @25psi so you should be fine.

Enjoy.........will be a hoot on the road.

 

[Fordy]

Is it not the angle of the rod/rocket arm changes when using a different cam? I mean look at the tappet adjusters, Then causing them to run closer to the walls
Or
Cylinder pressure vs 1980 push rod metal

I looked into push rods from America but was going to correct the length but you need a adjustable length test rod then adjust and check the top of valve for centering the rocker arm on the valve etc

Everyone's head is different height different gasket so you can't really bulk buy

 

[DaveL485]

Is it not the angle of the rod/rocket arm changes when using a different cam? I mean look at the tappet adjusters, Then causing them to run closer to the walls
Or
Cylinder pressure vs 1980 push rod metal

I looked into push rods from America but was going to correct the length but you need a adjustable length test rod then adjust and check the top of valve for centering the rocker arm on the valve etc

Everyone's head is different height different gasket so you can't really bulk buy

If I were doing a big power C1J, I would use a billet cam, not a recut, to reduce the pushrod length problems.
Look at bespoke pushrods, as they seem a weak point. Certainly open up a channel in the head if you can to accommodate a thicker rod, make the rods from titanium or Nimonic for the best strength/weight ratio, i'd also look at the back edge of the rod to see if I could add material behind it NOTE: All of this might be bollocks, but i'd try anyway.
I'd also try and combine that with bespoke tappet adjusters and give myself lots of adjustibility on length, and look to join the pushrod top to the adjuster to eliminate the chance of the adjuster unseating if the valve floats at high boost.
Depending on the variance of length of adjuster, I might make the pushrod adjustable instead, with a fixed tappet (non) adjuster. I might even look at bespoke rockers so I could do stuff like extend the tappet adjuster back a bit to help with pushrod clearance in the head, which I could do because I could compensate for the slight rocker ratio change with my bespoke billet cam... 5mm of lift on the cam x 1.6 ratio = 8mm valve lift. 6mm lift on the cam * 1.5 ratio = 9mm valve lift (blah blah, you can fuck about with numbers like that for days).

...and so on and so on. Its all do-able if you want to, and if you have the time and money to invest. My cylinder head took four years to spec and build.

 

[Mark Davis]

The way I need to look at it is I bought the car March 15 and spent pretty much all that time messing around with it in various forms so for the time being ill stop mucking with power, my original plan was always to reach 250hp and I'm not too far off now. The cars a keeper so I'm sure this time next year I'll start fettling again.

I've got a list of things I'd still like to do;
Spray and fit new bumper
Spray and fit integrale bonnet to see if I like it
Spray and fit ph1 rear arches
Get some rust treated on doors
Digi dash
Launch control
ALS - at some point
EGT Gauge
Oil pressure gauge
Campus filler neck
The list goes on..........

Also need to sort new house, new daily and keep the wife happy.

 

[Brigsy]

If I were doing a big power C1J, I would use a billet cam, not a recut, to reduce the pushrod length problems

My piper285 is ground from a billet and the tappet adjusters are still right down. I think its pushrod material, catching the head and possibly valve spring related i.e seat needs lowering or coilbound. All of my pushrods have witness marks on where they have caught the head so the hole definitely needs opening up. Still all these years and i have not actually managed to bend one yet