SBF reliability, servicing, costs...?

Jono · 10-29-07, 09:58 AM

Still mulling over various options engine wise for my Corty. I really still want an alloy block 302/347 (or similar), but have been exploring other options due to cost.
I know theres a huge number of variables, but for 6k miles a year, mix of track days and road use, what sort of things are likely to need doing engine wise (either service or replacement of parts), and what sort of running costs could I be looking at with SBF?

I have been considering a TVR AJP engine. PLEASE don't bother with the usual "Ford in a Ford" tirade as it is just really unhelpful, and hardly constructive. Phew, got that bit out of the way....

Reasons for this are I can pick up a used 4.2 AJP V8 complete with gearbox for under £4000 GBP. The engine is alledged to weigh around 120kg

(262lbs). compare this with (I'm guessing) 350lbs for an all ally SBF and this sounds pretty good on paper, with around 360bhp and more available. for the all ally SBF I reckon I'm going to be lucky to get change out of £13k GBP for engine and 'box so you can see why it seems an attractive option.
Ok so I'm comparing a new engine with a cut out, but even then still saving 9 or 10k! I've never seen a 2nd hand ally SBF either.
It appears that running costs can potentially be very high, so I wanted to compare these with running costs for an SBF to make a more informed decision.
I reckon the Ford is probably much tougher, but £9k gets a lot of repairs/servicing.....

Any thoughts?

Ian K · 10-29-07, 11:50 AM

I'm not too familiar with the reliability of the TVR AJP engine, but a new all alloy 302
with a mild build with the right heads will easily get you 360HP or more, and will be
pretty bullet proof. And, new vs. used, I'd go with new.

Ian

MikeP · 10-30-07, 07:54 AM

Whilst an AJP engine looks good on paper and they do go very well I think in terms of reliability and also costs when they do go wrong I would go the Ford route. Just compare the numbers made. There are about ten different companies making alloy heads for the Ford small block and about six firms are casting alloy blocks. How many people do TVR AJP stuff? Have you checked out the cost of a one off exhaust manifold? The TVR box is not a transaxle so you would need to factor in the cost of a one off bellhousing to your choice of transaxle. The figure for the weight of the AJP sounds very low. Also a reasonable Ford 347 will have 400hp+ and a wall of torque compared to an AJP and will be very nice to drive.
When you come to sell the car you will also find that most buyers will want the Ford motor (not a tirade – just a fact of life) - check out what cars are worth with Ford versus Rover V8s. GT40s tend to be worth the sum of their parts. You are putting your money into this - I'm sure you would like to get most of it back when you sell.
However try a test. I have just had the opportunity to compare a TVR Griffith 500 (big rover v8) with a GT40 with a moderate spec 302 (335hp) so have a drive of a TVR with an AJP and a forty with a 347 or other healthy small block. The cars are similar in weight so hit the loud pedal and see what happens! It might still not help your decision but it will be good fun!
Cheers
Mike

Keith Hardy · 10-30-07, 08:44 AM

SBF annual servicing costs? Built right to begin with - 1 set of plugs 1 oil change a couple of filters -cheap as chips.

The TVR motor is a great race proven piece but quite rare & "exotic" by comparison, and the key to the mechanical components of a '40 is simplicity, power and reliability.

This is no tirade (who cares, it's a public forum) but the SBF will be the cheapest HP you ever made + as others have said, all the parts are readily available for mating to a transaxle. You don't have to go with all ally - start with the lightweight AFR style heads on an iron block and work from there, with 400 ish hp as a realistic initial target.

It will be quite enough fun.....

Good luck with whatever you decide.....

Jono · 10-30-07, 09:48 AM

I think that's kinda what I wanted to hear, in my heart of hearts I really want to go the Ford route, and I think I would soon end up spending more in servicing/spares on the AJP route. Like you say, specialist wise there are plenty more for SBF, and AJP is a bit more specialised, and being out of production will probably not be long before parts begin to get scarce.
Thanks for advice.

Jim · 10-30-07, 12:37 PM

I think that if you're that concerned about cost you shouldn't be building a GT40. My .02.

Small block Fords are pretty cheap to build or buy today. Almost as cheap as a small block Chevy.

Dutton · 10-30-07, 03:49 PM

Jono,

Keith is right. These engines are pretty inexpensive to maintain.

When I started seriously planning my 40 a few years ago, I had intended to take a lower cost approach to the car as the combination of low horsepower and a reliable Audi transaxle has been successful in many 40 builds in the past. GT40s don't exactly weigh a lot so even that 'economy' combination should be more than enough to get ones attention!

As I got deeper into the project and actually started writing checks, I reached a point where I said to myself 'Oh, hell, just do it...' and decided to spend those few extra dollars and build MY car in the way that pleases me the most... higher horsepower engine, ZF transaxle, Smiths gauges and so forth. It may not be right for anyone else on the planet, but it will be the 40 I've dreamed about for far too many decades now (oh and by the way, I have discovered that a 'low cost approach' to a 40 build is strictly a fantasy).

My point is if you want to go with TVR power, by all means do so but be sure you're doing it for all the right reasons. It's your car, my friend, so build it how you want it... but I urge you to avoid building your car in a way you'll be disappointed in later.

We're all very much looking forward to seeing your build thread!

Best,

T.

Jono · 10-30-07, 07:21 PM

Err, think I should probably come clean for those who haven't seen any of my other posts, I'm not actually building a '40 (although I sometimes think it would be cheaper). Been coming on here since I found the site when searching for info on SBF's a few months back.. I'm actually building a Cortina.

I know, the engine's in the wrong place etc. etc., Sorry....., but at least it says Ford on the front.
The basic plan is to build a road legal track car, a classic touring car inspired V8 beasty, with a nod to the racing capris of the 70s.

Despite that I've been really pleased so far with the friendly/helpful atmosphere on here, thanks to all for the advice so far. Let me know if you still want to see a build thread!

Back on topic, I think Crossle43 probably has the right advice, that I should build the car how i want it, even if it takes slightly longer /costs a bit more, trouble is you start looking at /wanting the best of everything and cost soon starts to spiral.