SC or LS1? advice needed please

[tvrlee]

I am looking to upgrade my chim 400 over the next year or so, its a good condition '94 with 56K miles on it and would like some advice on what to do.

My two options at the moment are to go down the supercharger route or replace the enginge with a LS1, costs are about the same as i can get the LS1 replaced with the help of DIYCERB who is putting one in his Cerbera at the moment, what i would like to know is what you all think is the best option.

I was also wondering if anyone near to Lymington, Hampshire has had the SC fitted to their 400 that i could see and possibly test drive?

Many thanks in advance.

Lee

[Blues]

Lee, i have just had teh SC fitted to my 450.
OK, so its not a 400, and i'm not in Lymington, but feel free to PM me if you want to pop over and have a look and a ride

[Boosted LS1]

A home brewed forced induction system will be the cheapest of the lot assuming you can do some stuff yourself. Ecu would need changing for something mappable though, but you'd get launch and traction control included.

[Chequred Demon]

I have considerd the same options for my Chimp 400.

I am sure SC / TVR Power know what they are doing and the extensive testing looks very impressive:-

Personally I would not go the supercharger route unless I first installed a new Cossie 4.5L block. In my IMHO I think there is a distinct probability that the extra pressure and heat placed upon an original Rover block could cause the liners to move. A 400 should be better than a 450 or 500 in this regard, but read Des Hamill's "Power tuning RV8" book and you will understand the problem. My experience of Super Chargers on American V8's is that they are very thirsty on fuel. In addition the 450/500 have a bigger clutch and brakes and so again if I were to do it I would also change them both. I think I would also go for low compression stage 3 heads as well.

Personally I would go for the LS2 engine instead of the LS1, but in either case I whould change the T5 for a Tremec TKO60 or similar. I would probably go the carburettor route (as sold by British American Engines) on the LS2 and remove the "Fly by wire" throttle.

I think in either case I would also want the BTR differential instead of the GKN.

Just my thoughts.

[tvrlee]

Thanks for the comments so far, ideally i would like to try out a SC400, for a more comparable test, but thanks for the offer Blues.

[im]

tvrlee said:

Thanks for the comments so far, ideally i would like to try out a SC400, for a more comparable test, but thanks for the offer Blues.

I've got one. If you want to pop across to West Sussex in your Chim I'd go out on the local by-pass and we could 'drag' them side by side - staying within the law of course

Then you could park up and I'd take you for a quick spin.

Unfortunately, unless you can supply documentation that you are insured fully comp to test drive my car I couldn't let you drive it.

The car is some 50bhp more than a 5L so wouldn't want you 'losing it' first time out with no insurance...

If you can get Insured then no problem, come and have a go - but the insurers MUST be aware that you'll be driving a supercharged car.

As I say, if you can't get insured I can still demonstrate.

HTH

[Boosted LS1]

You don't need to worry to much about excessive cylinder pressures if you use low modest boost, say 5-6 psi. You just get the pressure lasting for longer during the power stroke hence the big torque hike. An example, diy rotrex install, £2k for the rotrex and oil lines etc, £150 for mounting bracketry, £150 for belt and s/c pulley. Then it's about mapping and tuning. Or, single turbo install plus mapping appx £2k or a good bit less if diy. Chevy lsx is a good install but initial investment is a big hit! Fine if you intend to keep the car and it can be developed to make huge power should you decide to grow even bigger horns

[hiltonig]

I looked at changing for a Tuscan but in the end its going to be the SC route, why ? well it keeps the original rover engine which means its british in a british made sports car. Yes the American engine is powerful etc but in my book it looses that orignal flag waving appeal. Why not try the demo cars and then decide. also its an easy conversion, I once had a charged VR6 and just loved the way it changed the driveability of the car.

Edited by hiltonig on Monday 21st April 21:43

[jsr]

I also have a 94 400, but unfortunately the SC Power supercharger is only for the serpentine engines. Dont fancy converting the pre-serp engine to serp spec, though i've been told it's not too expensive to DIY. Not sure i'm technical enough to plan a custom SC install

I am very interested in a single low pressure turbo. I'm not after big power, just a bit more kick from the 400. Also reckon i could fit a DIY turbo!

Boosted LS1 - i noticed your turbo RV8 manifolds a few weeks ago during a google search! Do you produce a single turbo kit? If so, would love to know more details

[Chequred Demon]

I agree Boosted LS1

With that little pressure I don't think there would be an issue.

As an illustration: I worked for Lotus during the M100 days and they had to turn down the boost on the turbo from 22PSI to I think 18PSI, which meant the Isuzu lump would last 100K for warranty purposes instead of about 60K, if my memory serves me correctly?

[Meatball]

mmmm turbo

[neal1980]

I was only on the phone to mike(boosted) regarding this the other day. He mentioned he was interested in developing a single turbo conversion for the Chimaera's. Basically a low boost max 5-6psi on all stock components. It would involve a one off Y piece (plenty of room down there). Hes looking for a guinea pig so he can get the manifold made. Around 2K

I reckon this is def the way to go. Ive collected bits already for this. Turbo, intercooler, spare Y piece and have just gone to megasquirt for fully mappable fuel/ignition.

Look how well the supercharged kits transform the cars :-)

[Boosted LS1]

The kit idea was something discussed with Joo at TCS. I'd produce a custom cast 'Y' piece to mount a hybrid turbo to. I'd do the in car installation onto the stock engine fabricating anything required. Off boost the car would still drive as normal because the compression wouldn't be lowered but once on boost you'd get a healthy increase in torque (appx 30-50%) and appx 280 bhp. The car would then leave me and go to Joo's for a remap/check under boosted conditions. I'd provide a voucher to cover that cost. Expected cost to be £2k and I'm not vatted. The reason I've not done this yet is that patterning costs for the 'Y' piece are substantial and I'd prefer to have a customer on board before I spend a lot of money. Another advantage of the conversion is it's bolt on, so engines can be changed as and when.

[im]

I can certainly see the appeal of a £2k price point. What warranties would you give?

[That Daddy]

If it was not for the silly place of the original cat then a nice turbo stuffed there would be good(plenty of room and cooling),dont know where you would situate a/the cat though

[neal1980]

Forget the cats im guessing it wouldnt sound too loud either with the turbo in there. Get a friendly MOT tester

[jsr]

This just got very interesting! If the turbo could take a standard 4 litre car to approx 280bhp and 300-340 lbs ft and for about £2k, i'm sure it will be a big hit.

My number one priority at the moment has to be to get my chassis sorted - front left outrigger is not a pretty sight. In fact, there's not much of it left! But later on in the year, if no one else has beaten me to it, i will definitely be interested in the turbo conversion, even if i am the guinea pig (sp?)

[Pupp]

Any paricular reason why the manifold has to be cast... would much prefer to see a nice fabbed stainless jobbie in such a prominent position and once jigged would be just as repeatable? Worth the additional outlay to the customer I'd say

[Meatball]

very interesting for 2k
what would a low pressure turbo on a 300bhp 4.6 make ???

[Boosted LS1]

Pupp said:

Any paricular reason why the manifold has to be cast... would much prefer to see a nice fabbed stainless jobbie in such a prominent position and once jigged would be just as repeatable? Worth the additional outlay to the customer I'd say

Stainless is weak and expands a lot. Also making something like an oxbow from stainless would be virtually impossible especially given the pipe diameter. A casting is strong and can support a turbo plus the casting will be supported as well.