R30 Skyline Lsd's & Fitting Turbo To L24/26e N/a Motor

[mavo]

Hey i'm lookin for info on my recently purchased r30.

it has a L26 fitted out of a zed with the head from an L24E with L20ET turbo manifolds, turbo, and oil pump. the fuel system has been upgraded with VL Turbo Injectors, High Pressure Regulator and a better fuel pump plus the airflow meter has been tampered with. my questions relate to things like the vacume advance on the dizzy and wether or not the engine is set up right. the engine performs well but seems to dislike anything over 5000rpm not like the N/A L series 6 cylinders ( 2.8, 2.6, and 2.4 i've driven all three ) it feels like the performance has hit a brick wall and starts to break down plus the radiator is getting pressurised yet it has a metal head gasket fitted and i'm fairly sure its not blown.

plus anyone with knowledge on LSD's to fit the R30 or LSD's that will fit with minor mods your help will be greatly appreciated

[Adriano]

MY guess is that the L20 turbo would be choking the setup. Does it have an intercooler? If not the dizzy may have been regraphed to reduce the overall advance, hence killing the top end.

These motors dont seem to make hp even with pretty big setups(which you dont have) They are nice and torquey, but dont have a great deal of top end.

Im not sure if they are a long or short nose diff, but if they are long nose(which i think they are)then you can fit late model lsd centre to your crownwheel and housing, but you will need axles made to suit, or you can get them from the states. The stock axles are the weak link anyway.

[discopotato03]

Hmm , R30's . I was there a few cars back with a quite clean DR30 (FJ20ET) .

Before digging into the mechanicals be warned that it's very easy to spend heaps on those cars and not be satisfied , IMO their worst features are that semi trailing arm IRS and prehistoric drag link steering . The long nose R200 is a good thing .

Personally I'd lose the R30 quick and get an R32GTST for far more modern exerything .

That aside and back to the Nissan L series , probably most let down by their heads . Not within a bulls roar of an RB20 head (L20a head) or an RB25/26 head (L28 head) .

As you possibly know Nissan only turbocharged the L20a (2000cc same bore and stroke as RB20) and the largest or L28 - L28ET .

There are people here in the classic section that live and breathe L6 turbos but they are limited in production (read affordable) tune .

There were siamese core L28 blocks and things like very large chambered P90 turbo heads with raised roofs and shorter valve stems . They were built in an era when production cars had quite low static compression ratios and no intercooling .

So with the Turbo head/low CR/different pistons/exhaust manifold I think lifted from the L20a ET/slightly larger injectors (250-280cc ?) they had the 280Z and ZX turbo cars .

Digging deep into the memory bank but I think some turbo L28ETs had a crank trigger and a "distributor" with a single sync pulse output only .

As for the turbochargers yes they were old T3 series dinosaurs with housings supplied by Nissan .

The L20a one is supposed to be really small in the turbine housing which would have been necessary to get response out of 330 odd cc cylinders . Very early RB20DETs also had real small turbos - the bush bearing ones .

Its a long time since I've seen an early T3 with Nissan housings on them but I think some Z18's and L20a ET's had a turbine housing A/R ratio of 0.36 where late FJ20s/some z18's were 0.48 and early FJ and all RB30ET's had the larger 0.63 A/R turbine housing .

Having low compression ratios and no intercooling kills bottom end power and to get it back they had to resort to small housings to get some squirt in the "mid" range . Small turbos are exhaust side restrictive and this stops them having much of a usable rev range except round the burbs .

If you really want to persue a turbo L6 I wouldn't go about it the way many do by chasing up old hard to get expensive L28ET bits .

I'd go with the largest one made which was the L28 but they are a pain in an R30 because they are designed to have the sump reservoir at the back insted of the front and altering the pickup is not a simple thing . I think the MQ Patrol one may have it the right way for an R30 but check up on it .

Those P90 open chambered heads are fine for low CRs but you don't want that . The very first of the MR30 2.4E's (1981 ?) had a better head casting than later emission heads and these have the closed heart shaped chambers similar to a real L16/18 SSS 219 casting head . I think all L4/L6 have the same valve spacing so the largest std L28 valves should go in but may need to change seats depending on what size and material the L24 head has . Pistons would probably have to be made for a turbo app . Crank and rods are good and if you used a BB turbo the oil pump should also be good .

The exhaust manifold is what you'd expect from the 70's so with a clean up it's livable .

I wouldn't go overly big on the turbo because you want some response from the limited exhaust gas flow available .

I couldn't bring myself to throw that much money at any R30 , its never going to feel remotely like say an affordable R32GTST handling wise - no matter what you do to it . You never know how much you miss rack and pinion steering till you dont have it . Rebuild bits for R30 steering boxes don't exist - period . Front ball joints , non replacable buy arms if you can still get them - ouch ...

Four bolt hubs and the only wheels that truly suit them are rare Rays engineering forged ones like my DR30 had , weird reverse rim thing . Five stud conversions very involved and exy .

Gearbox is the short narrow geared 71 series - suits the long L6 in R30 .

R30 R200 rear drive shafts are thin on the ground now and if you want a real four bevel gear LSD it means Nizmo .

I'd be doing myself a favour and buying a Skyline that comes with multilink suspension/four piston brakes/five stud hubs/an EFI turbo twin cam engine/stronger gearbox/better parts availability/better resale value .

Your money your call .

Cheers A .

[nIsMo86]

Lol...way to talk him out of an R30!

A mate of mine's dad runs a workshop that specialises in old nissans, datto's, Z's etc and are very good with them. They also build rally cars and race them. If your located in sydney they could help sort it out.

Stewart Wilkins Motorsport

02 45772400

www.swmotorsport.com.au

I dont know much about L series motors so hope that helps!

[mavo]

MY guess is that the L20 turbo would be choking the setup. Does it have an intercooler? If not the dizzy may have been regraphed to reduce the overall advance, hence killing the top end.

These motors dont seem to make hp even with pretty big setups(which you dont have) They are nice and torquey, but dont have a great deal of top end.

Im not sure if they are a long or short nose diff, but if they are long nose(which i think they are)then you can fit late model lsd centre to your crownwheel and housing, but you will need axles made to suit, or you can get them from the states. The stock axles are the weak link anyway.

yeah it is intercooled ( alloy front mount + alloy pipework ) and the dizzy has not been modified at all since the turbo was fitted i think your right though the turbo gives great midrange and then flattens out alot. how late can i go with the lsd centre the diff i have is an R180 with a mini spool fitted and it's getting to be really annoying.

[discopotato03]

Yep speak to Stu and Jacko , they will tell you the pros and cons and probably suggest a Zed or an R32 .

Have seen 100G Zed builds out there .

A .

[Adriano]

You can fit r32/33/34 lsd centres to them, just need to make up some collars for the crownwheel bolts, but you need an r200 carrier.

[aDrew_C]

You can fit r32/33/34 lsd centres to them, just need to make up some collars for the crownwheel bolts, but you need an r200 carrier.

No need if he has a R200 longnose, rebuild the thing and tighten it up. They're great diffs, 2-way mechanical, just very lose from factory.

[Adriano]

Except i think his is a single spinner

[mavo]

Except i think his is a single spinner

nope its a locker and a f#$kn frustrating one at that

[Sky084]

Hey i'm lookin for info on my recently purchased r30.

plus anyone with knowledge on LSD's to fit the R30 or LSD's that will fit with minor mods your help will be greatly appreciated

The '88 Z32 (I think) 300Z LSD will bolt right in, but it may have different flange spacing, so you may have to get a tailshaft builder to make a new one. That's what i had to do. Went with a 70mm from Adelaide tailshafts.

[Sky084]

Hmm , R30's . I was there a few cars back with a quite clean DR30 (FJ20ET) .

That aside and back to the Nissan L series , probably most let down by their heads . Not within a bulls roar of an RB20 head (L20a head) or an RB25/26 head (L28 head) .

As you possibly know Nissan only turbocharged the L20a (2000cc same bore and stroke as RB20) and the largest or L28 - L28ET .

There are people here in the classic section that live and breathe L6 turbos but they are limited in production (read affordable) tune .

There were siamese core L28 blocks and things like very large chambered P90 turbo heads with raised roofs and shorter valve stems . They were built in an era when production cars had quite low static compression ratios and no intercooling .

So with the Turbo head/low CR/different pistons/exhaust manifold I think lifted from the L20a ET/slightly larger injectors (250-280cc ?) they had the 280Z and ZX turbo cars .

Those P90 open chambered heads are fine for low CRs but you don't want that . The very first of the MR30 2.4E's (1981 ?) had a better head casting than later emission heads and these have the closed heart shaped chambers similar to a real L16/18 SSS 219 casting head . I think all L4/L6 have the same valve spacing so the largest std L28 valves should go in but may need to change seats depending on what size and material the L24 head has . Pistons would probably have to be made for a turbo app . Crank and rods are good and if you used a BB turbo the oil pump should also be good .

I run an L24 block with L26 rod and crank, 180B pistons, A87 head and get 196rwkw with 563Nm of torque at 5700rpm. This is done on dedicated LPG and no computer, so to say they are not good is sorta wrong!

[discopotato03]

From the Factory R30 R200 LSD's only had I think one set of active plates in each side of their production LSD center .

The go is to buy extra sets of plates and replace the wide spacers with more of the active plates .

Jacko explained to me that most OEM plate type LSD's aren't designed to work well because Joe/Josephene average don't like the noises and effects that a "properly" functioning one makes .

I carried my "plated up" long nose R200 LSD from the Bluebird to the DR30 and with ~ 65 odd lbs of static preload it work well - for me .

Trust me , DRIVE an R32/33 now you know what an R30 feels like and make your decision . I went for a spin in Skid33 and not long after bought one .

Never looked back .

Edited July 3, 2009 by discopotato03