Ginetta G15 SC and imp stories

chris · Post by **chris** » Sun Mar 25, 2012 8:58 pm

thought I would share a few things of progress, if any ones interested, hopefully ready for nat.

my mates seat, frames made by me

mine..

Chris

Lotus-e-Clan · Post by **Lotus-e-Clan** » Sun Mar 25, 2012 10:02 pm

It's gonna be a cracker!

I see you have galvanised rear trailing arms?

Did you get them done?

If so, how did you protect the bearing and bush housings etc?

I fancy a set of galvanised rear arms myself.

chris · Post by **chris** » Sun Mar 25, 2012 10:13 pm

ImpManiac · Post by **ImpManiac** » Mon Mar 26, 2012 12:15 pm

Chris, the car looks stunning! Really excellent work.

Is that a turbocharger lurking in that engine bay?

Bad lad!

IM

chris · Post by **chris** » Mon Mar 26, 2012 12:54 pm

Haha, yeah its where the imps engine ended up

oh well will have to do for now

Chris

chris · Post by **chris** » Thu May 31, 2012 12:37 pm

Hi all, basically all finished now, need to touch up the millions of build scratches Ive put on it. Taxed, Moted and Rolling roaded which didnt go to plan, booked again and in the process of stripping and rebuilding my turbo!

Heres some pics next to a clan so others can shake their monitors in excitement

Rare/medium please

Question though, if the gearbox keeps popping out of 1st and 3rd have a got my engine/box to far away or to close, I think it could need spacing more forward

nothing some loose bolts and a Crowbar cant sort!!

See you at national.... or shows before!

Chris

basil imp · Post by **basil imp** » Thu May 31, 2012 12:43 pm

Well done Chris! How does it compare to the turbo imp?

chris · Post by **chris** » Thu May 31, 2012 12:56 pm

rubbish at the moment,

Due to the turbo oiling everything from the doors back and through all the pipework, the throttle was restricted at 1/3 opening as a circlip was in the way once that was moved out of the way the plenum kept blowing off the carbs under load!!

However the MJ and Edis was faultless and works well, temp gage is a Chinese make believe one which needs to come out probably with every other gauge, oh and fueling was spot on after smaller .9 jets went in

So the action list is.

rebuild turbo
Additional centre strap on plenum
New carb rubbers as Ive melted them
Dirve and prove it
RR again on the 4th July.

Chris

chris · Post by **chris** » Thu May 31, 2012 2:56 pm

Porsche viper green from 1973 the original mix. code 225 or 255 one of the two lol

Dave ' Linwood ' Lane · Thu May 31, 2012 4:51 pm

Stunning ,

imp.sport · Post by **imp.sport** » Thu May 31, 2012 4:55 pm

Green as Green gets....

Nice to see it this far on. PM'ed you BTW

chris · Post by **chris** » Thu May 31, 2012 6:04 pm

Cheers all!

chris · Post by **chris** » Sat Jun 09, 2012 5:54 pm

Well I tried what I thought I needed to, ie using the correct washers on the engine mount and still not staying in 1st and 3rd unless you keep hold of the gear stick....

Considering that the carpet is now nicely fitted Ill be leaving it like that now till next winter lol, I will however check the slots on the gear assembly cheers Dave good point! I should be able to undo, slide and tighten up without disturbing the interior if I have the slot space left!

First show

Drove well, boosting nicely, felt very fast and much more fun than the imp, love it!!

differance with it is, it might not be as overall powerful but in real world on the the road situations is sooooo much quicker, couldnt believe how quick I could overtake people on B roads

Need to tell the RR guy that the timing can go up to 34 degrees-ish as he was concerned and left it on 24 max I think, so currently slightly sluggish through the range.... room to improve anyhow!!

Can anyone recommend I.e Eric and Pete etc lol, what timing I should be aiming for on the MJ?? whats safe on an imp engine say max 7800rpm, as my low blow turbo is out of puff well before 6000 anyhow

, If we start on that rev, I can drop down accordingly on the next set-up attempt.

Cheers
Chris

bazzateer · Post by **bazzateer** » Sat Jun 09, 2012 6:02 pm

chris wrote:

Interesting looking location Chris, love the little kiosk and pump, where is it?

basil imp · Post by **basil imp** » Sat Jun 09, 2012 8:34 pm

Jelous! It's looking great!

Lotus-e-Clan · Post by **Lotus-e-Clan** » Sat Jun 09, 2012 9:35 pm

Not sure if you mean me or Pete R, but anyway here is some food for thought, although mine is obviously n/a and I take it you are saying that above 6000 rpm yours is effectively n/a 'cos the turbo has run out of puff? Eric is obviously you man for the turbo ign advance stuff.

I tried increasing the WOT advance above 6000 rpm to see if my engine liked it. On the log I noted a slight drop off of the rpm acceleration above the point the extra advance kicked in .. (see below):
Pink = ign; Blue TPS%; Yellow = rpm

So I removed the step in the advance curve @ 100% TPS above 4500 rpm and it was better without the increasing advance. (see below)

Here is an old ign map showing a step from 34 @ 4000 rpm to 35 at 6000 and skywards. I'm currently on 35 @ 4500 and no increase above that when using WOT. As you can see, part-throttle is a different story with loads of advance everywhere (see below). Bear in mind my SCR is 11.8 :1. A lower n/a SCR might tolerate a degree or so more @ WOT

chris · Post by **chris** » Sat Jun 09, 2012 9:39 pm

cheers for that fella, I did mean you

, Interesting your max is 34 which I thought it should be about, I never really knew what my old set up on dizzy was doing see!

Food for thought

Thanks
Chris

pimpdriver · Post by **pimpdriver** » Sat Jun 09, 2012 10:01 pm

Chris
This is the map that has been in the megasquirt since the first turbo engine. Its one I guessed at, and has been unchanged.
The timing has never been checked on a rolling road, it seems to work and there is no sign of detonation.

Eric

chris · Post by **chris** » Mon Jul 30, 2012 12:39 pm

managed to get the pictures restored with all my new spare time

Also been busy with the ginetta, exhaust change as the little one was just too little and restrictive, this was on the imp and worked well, very very quiet though! I think its got a baffle in the end which I cant get out without a lot of work, drilling out stuck bolts and hellicoiling so cant be bothered before national!!

Designed a new plenum which should work but again not ready for national so will look forward to fitting and testing that

also spent some time making roll cages, will be again ready after national!!

Ever get that feeling National comes to early??

Chris

chris · Post by **chris** » Tue Aug 07, 2012 8:08 pm

Hey all just wanted to give thanks to all that voted for my ginetta! Nice to see others liking my car that took myself 18months to rebuild and make my own.

Really good to finally get a first!! What class do I go in though next year?!

Before next year ill be....

Fitting different wheels
Making tailored door window frames
Have a proper running engine!
Fit my new digital speedo dash thingy
New front rad, 3 's' Core type
Roll cage fitted that Ive made

So yeah quite a bit going on as well as building a 1040 too which might be fitted depending on everything else!

Cheers again, great national with great mates
Chris!

chris · Post by **chris** » Wed Aug 08, 2012 10:22 pm

photo taken by rob

chris · Post by **chris** » Sun Aug 12, 2012 11:59 am

made some progress..

new dash piece fitted with gauge thingy will wire up the sensors when I take the seats out for cage fitting

and cage ready for powder coating then fitting

Slowly getting there through the list!

ImpManiac · Post by **ImpManiac** » Sun Aug 12, 2012 11:04 pm

Yours was a well-deserved prize, Chris.

As ChrisB said, your range of skills and your shear mastery of them is bewildering! The car is a credit to you and your hard graft.

IM

chris · Post by **chris** » Mon Aug 20, 2012 10:50 am

Well one more show left then its coming off the road for major work!!

Im fed up with the unreliable R1 carbs on boost, for 500 miles its been running pants then all of a sudden yesterday it was running like a train! Still strangled at top end due to the plenum but thatll all change around with my new set up!!

So Im going to build up my 1040 bottom end, Im feeling Ill fit my sport head this time with big valves and r17 cam, dont want too much overlap now! and aim for a CR of 8.5 or 9:1 instead of the 7.5:1 Ive currently got, should increase performance slightly too.

On the fuel side Im going to give up on carbs and go injection, big bold jump with megasquirt need to be understood and learnt! One thing I never wanted to bother with on the imp but since all this has been started with the lack of space on offer in the ginetta engine bay.

No intercooler, Ill go charge cooler if I can find a nice small one.

Injection maybe either bike bodies or Im currently liking the idea of a fuel rail fitted into a manifold with one throttle body from one of my favourite cars... the mk1 mx5!! should be easier and allow more room in the engine bay...

Ill be cutting holes in the boot lid for cooling, I was supprised to feel the other day the chassis was as hot as the turbo lol, been using it as a mazzive heat sink

So probably look out for a 2nd boot lid to leave this one as is.

Turbo manifold will stay as is for now whilst I concentrate on the fuel side of things and building up the bigger cc engine.

Will be wanting 150ish at the wheels this time...........why not eh!!

Been sorting things out.......

sorting out the engine bits which will end up as a 1040

I will be removing the rings and filling the grooves in the head, I dont want to run rings, Ill run a std gasket. Any preferred ways of filling the grooves?

Ill probably use the bottom one, its got its crank in position so should be easily matched up etc etc. Not sure I have the caps for the other block

New sumpo

benwick3 · Post by **benwick3** » Mon Aug 20, 2012 12:24 pm

In my opinion only way to fill the grooves is by welding and that then needs the head skimming. What's wrong with using wills rings, better solution in my opinion.

Pete Richards

chris · Post by **chris** » Mon Aug 20, 2012 6:47 pm

Spent some time looking over the sport head today, its not in the best of shape

Managed to get the badly rusted rings out, only one vented gas as I broke in to it, the others came out in bits and pieces.

On piston four the combustion chamber is badly corroded as shown, wondering if its fixable really

Im going to have to remove the valves no matter what. Any advice on repair? Guessing if its possible its weld again and machine back same as others?

Dunno how the last owner stored it, badly obviously

the mating face is showing signs of corrosion too, so a weld and skim's not going to be the worst thing.

picture of the top for the hell of it!

Cant remember the valve measurements now but earlier discussion showed an odd pairing but likely suited to turboing.

Chris

chris · Post by **chris** » Tue Aug 21, 2012 12:44 pm

been looking at my bare block and think Ive located the correct caps

the wear on the back one seems to cross over the two sides the same

Guess the bast way will be to bolt in a crank and see if it spins free when fully torqued up!

Wish I had sorted this out by now! If Im successful in my job hunt before eating into my 'dundancy package Ill get it going on 415 or 240v

bks974c · Post by **bks974c** » Tue Aug 21, 2012 4:29 pm

chris wrote:

Guess the bast way will be to bolt in a crank and see if it spins free when fully torqued up!

Chris

That wear is usually caused by the main bearings having failed and the oil scroll and block having an intimate coming together

I would not use as is as it will leak like a sieve as the crank and block need to be a close fit if the oil scroll is going to work as designed and even then were never that great. Possibly the reason its lying as a bare block having been abandoned and pistons etc used in another block, however there is now a solution,Stuart at Rodwells rear oil seal conversion can save the block but obviously adds cost to the project.

Scott

colin rooney · Post by **colin rooney** » Tue Aug 21, 2012 5:24 pm

chris wrote:been looking at my bare block and think Ive located the correct caps

Chris are you saying that the caps were not with the block that they were mixed up with other caps ,if so and you think you have found the caps for that block i would be very carefull even if the crank spins nice you could still have a cap that loose they should be lined bored and i have had the experiance of building an engine that was 1st off build by one of the so called race people who should know what there up to ,the engine in question alwayshad a small rattle and had bad oil preasure and when the water gasket let go after the engine had only done around 2,000 miles we decided to strip it and rebuilt it with new crank ground 10tou and race bearings new oil pump it spun nice but when it fired up there was a small rattle the same as what was in it before it blew up ,on strip down you could see that the centre cap bearing was ok but the front and rear had wear but only on the cap side which points to me that the crank was bouncing ,and when i measured the old bear they showed the same wear patten ,so if i was you i would get it checked for inline bore or get another block and have them liners fitted

col

ImpManiac · Post by **ImpManiac** » Tue Aug 21, 2012 6:02 pm

^^ What Colin said.

Beware!

With regard to the rear main oil seal, a man of your skill could quite probably fabricate an oil seal carrier and figure out a good way to affix it to the crankcase...

The block could live on, subject to a thorough inspection of the crankshaft bearing journal alignment.

IM

chris · Post by **chris** » Wed Aug 22, 2012 6:49 pm

gone into the unknown today by removing conrods and cranks etc!! Made sure I noted and marked what came from where and which direction..

pistons came out easy enough cranks looking good everything still had a good oil filming.

yep crank seems good and spun nicely before removing

around the backs nice too, much better than the other block!

Not that it matters as the liners are getting munched but why has this one lost a big portion of the top lip? what causes it? would that mean as an 875 this block would be junk?

then I got on with cleaning!!

Not fully clean yet as I ran out of cleaner type products but its much nicer to work with now and be around!!

Chris

ImpManiac · Post by **ImpManiac** » Wed Aug 22, 2012 10:21 pm

Nice work, Chris.

The block would have been no good for an 875cc build, although some say that it can be done. Me, I'd be happier doing what you're planning and going for a wet liner conversion.

IM

chris · Post by **chris** » Thu Aug 23, 2012 7:30 pm

yey! cages finally in colour!! will wait to fit mine over winter while the engines out and Ill fit my new rear GAZ shocks too since the right hand side original one has leaked everywhere!!

chris · Post by **chris** » Sat Aug 25, 2012 10:32 pm

Liners are finally free!!

As you can see it took hammers, a shaped tool, heat, wood, angle and a dog toy slid out nicely, now I just need to save up for the machining work

Also been looking over my fitted but never used 930 head, might fit that, it all depends on the CR when I start measuring the cc's etc. not too concerned with overall flow with the turbo, just want the best suited for CR.

chris · Post by **chris** » Thu Aug 30, 2012 10:21 pm

Hey all, started the strip down of the engine bits n bobs.

looks like the turbo front seals didnt last long after the rebuild luckily I never stopped looking for a spare new one so Ive got one waiting!

Finally off for the last time, hopefully all being well not going back on!!

Start of the new set up

So heres whats got me thinking now.............

Most setups with a single throttle body are set up like Option 2 in the below sketch where the Throttle body is before the plenum and the plenum feeds all four ports seperately so a nicely tuned one etc.

But my set ups slightly different, Im using a manifold which has all for ports fed from one hole so I think a set up like option 1 should be used, basically as per a carb set up, the plenum is before the butterfly etc only difference is my fuel is coming in afterwards......

So to continue on I wonder if Ill need a plenum at all? Ill have all the pipe work in place and an intercooler/chargecooler which should work as a storage of charged air?? Basically Im sure Ill have more than enough volume without plenum?!

Ready...... Discuss

Chris

james · Post by **james** » Thu Aug 30, 2012 10:39 pm

I don't think you need one either. Most single-TB port-injected stuff has a manifold a lot like yours (930 inlet, BTW?).

K11 - no plenum, injectors at ports.

(no turbo either, but pressurising the air doesn't alter the manifold's characteristics.)

Fairly sure that Dave Hampshire did basically the same but using a 28/36 manifold (with injectors at the ports) on his turbo setup too.

TBH, I think a plenum (option 2) would reduce snap-open throttle response - there'd be more volume to fill up with pressurised air. I think the normal TB-plenum-runners setup is used to try to get the airflow into each cylinder equally - but a standard inlet manifold without a plenum should be capable of that to a reasonable degree.

chris · Post by **chris** » Thu Aug 30, 2012 10:41 pm

Yep cheers james youve confirmed my thinking really, I was basically sold on the no plenum Idea as it did make sense lol.

Cheers fella, and yes its a 930 one, with a metro su carb flange welded on as its what I used on my turbo imp.

Chris

chris · Post by **chris** » Thu Aug 30, 2012 10:52 pm

Cheers man, Yep you helped confirm a lot for me, means Im going full steam ahead with what I had planned with the space available.

Thanks for the comments, hopefully Ill win Masterclass next year! Lots would have changed on it by then!

chris · Post by **chris** » Sat Sep 01, 2012 11:09 pm

Started to modify my intercooler today, basically all I can do with it until I get some funds for the welding!

chris · Post by **chris** » Tue Sep 04, 2012 9:55 pm

Finally got around to fitting the cage in!

Seats out

Cage strapped

Half in

Pushed in, one point I didnt think it was going in then suddenly pop in it goes, few scratches on it, its as tight as I could get it to the sides see

Carpet cut

From behind you can hardly see the top bar, and legs look nice and true

New shocks fitted, since one of the originals had leaked completely due to a damaged shaft

Tomorrow rear shelf trim will be cut to suit and seats back in!

james · Post by **james** » Wed Sep 05, 2012 12:42 am

Looking good there.

You need to make a little "G15 Ti" badge to go somewhere - out of Titanium.

chris · Post by **chris** » Fri Sep 07, 2012 12:36 pm

Throttle body arrived I needed to 'slot' the mounting holes but luckily it fitted

not much room but hopefully a 90 degree silicone will fit in

ImpManiac · Post by **ImpManiac** » Fri Sep 07, 2012 1:44 pm

That TB looks like it was made for the job!

IM

chris · Post by **chris** » Tue Sep 18, 2012 2:18 pm

Thought id have ago of making a bonnet as I want to do vents and things on one but leave my painted one alone as is!

First attempt didn't go very well but thus second one should be very useable..... might crack it out of the mould tonight.

chris · Post by **chris** » Tue Sep 25, 2012 10:22 pm

Slow progress currently as waiting to save up for new ecu, sensors, harness equipment etc etc and also have my dads imp to restore over winter too, including both outer rear arches and other pieces ill bend outa flat plate and shape in then an external respray early next year.

Ill be lifting out the megajolt and edis ready to shift on and send the to be 1040 block off for machining.

chris · Post by **chris** » Tue Sep 25, 2012 10:52 pm

Some photos..

imp, body is worse than we hoped to be honest, lots of work for me but Im going to concentrate on making it solid where needed and 'cleanly' painted for road use not bothered trying to win shows and stuff Its to be used maintained and most likely re-welded when needed

Basically I wanted to make sure we had an imp at imp50 not just the ginetta so Itll come up with me and dad with one of us driving it and the other towing the ginetta on trailer so I can kill it on track if theres going to be one....

G15 manifold and injectors/rail

First bonnet checking ideas for the venting

Wheels for sprinting, after nailing the imp back the other night for 120 miles I really got liking the Yoko A539s on it so a set of those new will be had for track use when I sprint next year.

Chris

benwick3 · Post by **benwick3** » Wed Sep 26, 2012 9:46 am

Forget the A539s if you want to be competitive go for A048s in soft compound if the regs allow it.

Pete Richards

chris · Post by **chris** » Sun Sep 30, 2012 9:04 pm

carried on with the lightweight vented bonnet today, started by cutting

then massively deep templates which I copied in fiberglass sheet

then after talking to sam who decided I couldnt be doing mine without him attacking his we noticed that it doesnt really need to be deap due to the area and air flow etc so now Im going half as deep i.e....

Glassed the corners in so the first piece was locked in place

chris · Post by **chris** » Mon Oct 22, 2012 9:09 pm

new wheels on, one side at least, night was drawn in before I got home and bolting on so will carry on at the weekend and take proper photos on the drive

chris · Post by **chris** » Wed Oct 31, 2012 7:40 pm

New technical cleverness