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Northerner
31-03-13, 06:45 PM
Hello everyone, I have fancied a cobra for a while now and I think I have got a AK kit in mind but I would like some information about engines as I don't know where to start.

Correct me if I am wrong but I am swaying towards a Rover V8 as they are cheaper than a Chevy V8. Also I would like to try and overhaul it myself as I would see this as a way into a hobby I always wanted to do, which makes it even cheaper as you can get 2nd hand rover V8s on the net cheaply.

But, I have seen people with 4.6 V8 rover engines. When I scan ebay, they all seem to be efi, and I want carb. Now I'm an electrician not a mechanic and this is a learning curve, could somebody please help me get my head around how to convert this. Surely it's not just a case of changing the inlet manifold and plonking a carb on? I know you could just get a 3.5 V8, but is it worth getting the 4.6 V8 or 4.0 V8?

Any help appreciated, totally lost here!

Turbycat
31-03-13, 07:10 PM
Personally I'd try to go for an American V8 if you manage to afford it. I was fortunate enough (because of a bloody great motorbike accident!!) to be able to afford a factory built AK. I have pushed the budget to the max with mine and have gone for an LS3. I'm not that capable of crawling around doing mechanics since my accident so I wanted to go more towards the turnkey usable car as my first Cobra. I have in the past messed around with spitfires, lotus 7 reps and a spartan Trekka but those days have passed for me. There are far more informed people on here than me being a newbie myself.

Andy

Bobbins
31-03-13, 08:04 PM
I am building a 5.0L ford from a 91 mustang and so far I have saved plenty over buying an LS3 which is what I originally wanted but didn't have the budget. A few well chosen performance parts and you will get the horse power to match at half the price. I have stuck with the EFI simply because I want to be able to drive it at the end and not worry so much about MPG.

good luck with whatever you choose. I have had great fun so far putting my engine together. Pic attached!

johannlitherland
31-03-13, 08:26 PM
Hello everyone, I have fancied a cobra for a while now and I think I have got a AK kit in mind but I would like some information about engines as I don't know where to start.

Correct me if I am wrong but I am swaying towards a Rover V8 as they are cheaper than a Chevy V8. Also I would like to try and overhaul it myself as I would see this as a way into a hobby I always wanted to do, which makes it even cheaper as you can get 2nd hand rover V8s on the net cheaply.

But, I have seen people with 4.6 V8 rover engines. When I scan ebay, they all seem to be efi, and I want carb. Now I'm an electrician not a mechanic and this is a learning curve, could somebody please help me get my head around how to convert this. Surely it's not just a case of changing the inlet manifold and plonking a carb on? I know you could just get a 3.5 V8, but is it worth getting the 4.6 V8 or 4.0 V8?

Any help appreciated, totally lost here!

You don't have to keep the efi and in fact building it yourself sticking with a carb set up is easier than Efi initially. I put Efi in in the end for fuel efficiency and performance ( better power etc) the carb options are endless, you can even go crazy with Jenvy and they look fantastic and growl like a pack of wolves. The good thing is with the Rover is its an aluminium block so light and there are plenty of parts and options available. The ultimate option is the LS option but costs a lot more. I looked long and hard at different engine choices and when one day I spoke to a chap who built a rover Dax sold it and made 383 stroked Chevy Dax, be missed his rover one handling wise. I've test driven a rover and it was more power than I would ever need or want on the roads, was quick and sounded awesome, it was a fairly refined drive too.

One thing to look out for is the different rover blocks and there associated issues, 3.5 is relatively bomb proof, 3.9 can have cylinder liner and overheating issues, there are some better cross bolted block options out there and they are bomb proof if properly built and specked. You can spend a lot of money on a rover block too! So if its just the price your worried about you can get some very cheap Chevy blocks or even turnkey entry level engines for a lot less than a turnkey high specked 4.6 rover block, which will be around the same bhp as an entry 5.7 litre Chevy.

Truth is there is no right or wrong way just as long as its a V8! Actually I will correct what I said myself, the right way is a Ford 427 side oiler with turkey pan! But realistically that could cost more than a budget build ;-)

Sidecarbod
31-03-13, 09:18 PM
The engine that you use has to meet the emission levels that were set when the engine was in use in its original car. You need to read up on this stuff of at least get clear info from this forum etc in order to avoid problems when it come to the IVA test.

The 4.6 Rover lumps ran with EFI therefore the levels will hard to reach with a carb, possibly impossible to reach with a carb.

A 3.5 lump will be the cheapest way to get a V8 in your car and you could use a carb if you get an early-ish one but it will have the least BHP. Most RV8 lumps that you see on Ebay will be totally knackered by now and will therefore need a complete rebuild. Rebuilding one of these engines is no cheaper than any other V8 although I guess the gearbox that you will need will be cheaper than say a Tremec which is the sort of box that you need for a yank V8.

My 4.6 does actually run with a carb but that's because my car passed the SVA test with an old 3.5 lump fitted, a couple of years later I fitted a 4.6 but the emissions were set for my car with the 3.5.

cobracol
01-04-13, 07:41 AM
Hello and welcome to the forum, unless things have altered, standard rebuilt Rover 3.5 3.9/4.2 ect probably cost about same as basic chevy, Rovers were pricey to get big HP out of, so i went stroker chevy route, Ford V8 was a lot more at the time i built mine, i dont know where exactly where up north is, but you are welcome to have a look at mine, you can also see another Chevy one half built near me, and a Ford v8 and Cossie V6 within 2 mins

GASAXE
01-04-13, 08:52 AM
You could of course go back to the original plan and get a ls cut out as people like to call them but they have increased in price what with the exchange rate etc, i did it and have yet to hear of a bad one, i am also up north, by the way you get a 6 speed t56 in the bargain.
Geoff

jonny m
01-04-13, 09:08 AM
I had a similar dilemma when I built mine, and took the easy 'English' option of Rover V8.

Going from a 1.8 family car, I figured 3.5 V8 would be amazing, but the truth us they aren't that fast, and most with American engines leave me standing.

4.0 and 4.6 are problematic with dropped liners from overheating, plus getting a good manual gearbox and bell housing will be expensive.

Personally, I'd save up the cash and go American

kitcarsareus
01-04-13, 09:16 AM
something like this (nowt to do with me)

CHEVY L33 V8 ALL ALUMINIUM V8 ENGINE LSX LS1 LS6 5.3 LITRE | eBay (http://www.ebay.co.uk/itm/CHEVY-L33-V8-ALL-ALUMINIUM-V8-ENGINE-LSX-LS1-LS6-5-3-LITRE-/290890102140?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item43ba66b57c)

A lot of bang for the buck

tonym
01-04-13, 10:33 AM
I had a similar dilemma when I built mine, and took the easy 'English' option of Rover V8.

Going from a 1.8 family car, I figured 3.5 V8 would be amazing, but the truth us they aren't that fast, and most with American engines leave me standing.

4.0 and 4.6 are problematic with dropped liners from overheating, plus getting a good manual gearbox and bell housing will be expensive.

Personally, I'd save up the cash and go American

There is so much wrong with this statement that I don't have the time to correct it :-) Suffice to say that I doubt if there are many American engined cobras out there that could overtake Sidecarbod and his Rover powered Sumo, so there :-) :-)

Northerner
01-04-13, 11:12 AM
Thanks for all the advice, I think I am starting to get my head around it a bit better.

I have looked at a few chevy engines now, but there are lots of variants that mean nothing to me. Is there somewhere to read up about these or would somebody be able to explain it? I mean, the difference between LS1 / 2 / 3 etc and what would best suit the chevy engines including gearboxes.

Lloyd Barnes
01-04-13, 11:15 AM
LS1, LS6,LS2, LS3, L99, LS4, LS7, LS9 And LSA Engine History - GM High-Tech Performance (http://www.gmhightechperformance.com/tech/0901gmhtp_ls1_ls6_ls2_ls3_l99_ls4_ls7_ls9_lsa_engi ne_history/viewall.html)

Might make useful reading. Don't dismiss an earlier carb version either.

Welcome from another Cumbrian (Ulverston) :-)

neil50
01-04-13, 11:27 AM
If you read the forums there are pro's and cons to all types of engine varying from initial cost, cost to upgrade, efi, carb, looks (LS are modern with plastic covers, but you may be able to change their appearance but I'm not sure, whereas old school have air filter on top, rocker covers etc that can all be chromed up if you wish). Most engines can be tuned to get the power that YOU want out of them but at different costs. The main things is to confirm what you really want out of the engine then look at the various options that fit into your plan and budget.

Sidecarbod
01-04-13, 12:44 PM
There is so much wrong with this statement that I don't have the time to correct it :-) Suffice to say that I doubt if there are many American engined cobras out there that could overtake Sidecarbod and his Rover powered Sumo, so there :-) :-)

Cheers Tony! (Although there are quite a lot of yank lumps that would out perform my engine, I guess as an overal package then the RV8 is nice because it makes for a good handling car, the other thing is where do you draw the line? my engine is quite 'mental' especially with the NOS but you can always go more 'mental' and it depends on what you are prepared to do on a public road!....They chuck you in prison these days for speeding!)

My posts in this thread have been aimed at the fact that the OP wants to run a carb in which case LS engines are out of the picture as are 4.6 Rover lumps

I do think that Jonny may have be referring to the 3.5 lump! In my humble they are just about OK if you tune them and set them up OK, many are not and are only kicking out approx 150 BHP which ain't that much. Really I guess it depends on what you want from your car, many are happy with the looks and the sound, I wanted a bit more performance.

jonny m
01-04-13, 12:56 PM
I do think that Jonny may have be referring to the 3.5 lump! In my humble they are just about OK if you tune them and set them up OK, many are not and are only kicking out approx 150 BHP which ain't that much.


There is so much wrong with this statement that I don't have the time to correct it :-) Suffice to say that I doubt if there are many American engined cobras out there that could overtake Sidecarbod and his Rover powered Sumo, so there :-) :-)

Yep, correct, I was referring to the stock 3.5 motors, plus getting them tuned to a high standard I'm told is big bucks !

Murray
01-04-13, 01:04 PM
The prices for those LS engines seem very reasonable, ie cheap! What's the catch there? Call me suspicious if you like!!
I would love the LS frugality over my Ford lump!!

neil50
01-04-13, 01:21 PM
The prices for those LS engines seem very reasonable, ie cheap! What's the catch there? Call me suspicious if you like!!
I would love the LS frugality over my Ford lump!!

I think part of the problem with the LS engines is the price of the "extras" you need to make them run. i.e. wiring looms, ecu's etc. I run a modified 350 Chevy so I am sure that someone who has a LS system will be able to explain this more.

GASAXE
01-04-13, 04:23 PM
To get the ls running you will need a ecu and loom, you can utilise the one that comes the engine, i managed to find a links ecu with GD loom cheap and you also need a efi fuel pump and regulator not a fortune really, Gd and Ak do kits i believe that are plug and play,
Geoff

Elanore427
01-04-13, 04:43 PM
If you read the forums there are pro's and cons to all types of engine varying from initial cost, cost to upgrade, efi, carb, looks (LS are modern with plastic covers, but you may be able to change their appearance but I'm not sure, whereas old school have air filter on top, rocker covers etc that can all be chromed up if you wish). Most engines can be tuned to get the power that YOU want out of them but at different costs. The main things is to confirm what you really want out of the engine then look at the various options that fit into your plan and budget.
Borla (TWM) now offer throttle biddies for the LS1,2 & 3 so you can get a more old school look and sound out of them...

Northerner
06-04-13, 07:05 PM
Thanks for all the help and advice!

The kit has taken a backwards step as the misses has persuaded me to book a holiday to Las Vegas, taking in the Grand, Zion & Bryce Canyons. Hopefully the Ford Mustang hire car can make up for the disappointment of not ordering a cobra.

Anyhow, I have managed to organise a trip to Stoneleigh in May so I can get some more tips and advice before I head out and get my kit ordered.

Maybe see some of you lot there!

Turbycat
06-04-13, 10:39 PM
Have a look at the AK stand when you get to Stoneleigh. The rolling chassis they will have on display will be my factory build chassis. It will be fitted with an LS3 engine so you'll some idea of what will be involved in the build.

Andy

garyjettrike
07-04-13, 12:51 AM
Thanks for all the help and advice!

The kit has taken a backwards step as the misses has persuaded me to book a holiday to Las Vegas, taking in the Grand, Zion & Bryce Canyons. Hopefully the Ford Mustang hire car can make up for the disappointment of not ordering a cobra.

Anyhow, I have managed to organise a trip to Stoneleigh in May so I can get some more tips and advice before I head out and get my kit ordered.

Maybe see some of you lot there!

I'm doing the same in august then going up north to Bonneville for speed week when are you going

Gary

Northerner
07-04-13, 09:23 AM
I'm heading out on the 23rd of June for 10 days, We are doing approx. 850 miles around the Canyons with a detour to Monument Valley over 5 days, the rest will be spent in Vegas. You never know, I might even win enough money to buy a cobra when I get back - fingers crossed!!

garyjettrike
07-04-13, 04:58 PM
I'm heading out on the 23rd of June for 10 days, We are doing approx. 850 miles around the Canyons with a detour to Monument Valley over 5 days, the rest will be spent in Vegas. You never know, I might even win enough money to buy a cobra when I get back - fingers crossed!!

if you spend another day in the car you could pop up north of there to the Kirkham factory Kirkham Motorsports (http://www.kirkhammotorsports.com/) i think i am going to pop in and have a look

BobMin
07-04-13, 11:14 PM
If you are going to be in Vegas then there is always the Shelby Museum. Got to be worth a quick detour!

garyjettrike
08-04-13, 01:51 AM
Iv got that on my list of destinations