Engine and Transmission Tech

Hi all!

I have a 3.5 SD1 RV8 engine, with some spec.( edelbrock carb, 3.9 efi cam, lightened flywheel, ported heads etc.). Not a bad engine (especially with the 3.44 ratio), but i need a little more torque for better acceleration.
I live in the middle of Europe (Hungary). RV8s not grove on trees here, and i don't know what to do. I haven't a tons of money, so...
Get a stroker crank (Buick 300, the "iceberg", p76 or anything else), with the suitable pistons, or buy a bigger engine?

Thanx for help

Wellcome neighbor. Probably not too many 300/340 Buick engines over there? No turbo or blower? Early motors will hold about 15lbs. boost with some prepping.The 4.0/4.6 is so improved over 3.5, I would try to get a shortblock. Your heads are probably ok for this build. If your cam is in good shape(lobes not worn), you might have it reground for more lift. Build your own hedders and save. Use the 4.0/4.6 crank(keep your fly-wheel).You can get 3.4" stroke with off-set grind of the 4.6 and run cheap sbc. rods/pistons. We've talked about many combo's in forum.. Good Luck, roverman.
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Tamas,

What vehicle are you talking about and usage as that has a big influence on what you can do to the engine.

To obtain more torque on a reasonable budget you really need a bigger engine, long strokes are good for torque which would mean getting hold of a 4.6 engine on which you can use most of your existing engines parts ie manifold and carb possibly the front cover so you can use the distributor. a decent high torque cam and some mild heads will release a bit more power.

Kevin.

My ride is a Ford Capri 1980. This RV8 engine is in it.
I would prefer to build a stroker rather than buy a bigger engine, because the machine work is relativly cheap in here, and get an other engine is nearly impossible (i was searching mine for a year).
Is it possible to use a 4.6 crank (after a "little" machine work of course) with custom pistons?
Which crank is the best option? What not too expensive, and easily available. (i think the p76 isn't come at able)

Tamas,

Your problem is you are starting from a 3.5 L small bore engine, most stroker kit now are based on the 3.9 or later blocks, you can stroke a 3.5 but in returns for cost you don't get alot out of it but you would increase torque to a certain extent.

Building a stroker engine isn't cheap what sort of budget/money were you thinking of?

There may be a way of using a 4.2 crank with some machined down 3.5 low compression pistons but I need to do a bit of calculating, this would give you a longer stroke but only 3825cc so only 300 cc.. bigger.

A 3.4" stroke will get you to 4.288cc but will require custom crank rods and pistons

If you could find a 3.9 out of a Range Rover that would be a much better starting point and Real Steel do a very good stroker kit for it to take it to 5.0 for a very reasonable £1600.00

Even the 3.5 can be made to produce 200+ BHP and still be quite torquey and in a light car like a capri will go pretty well.

Kevin.

Ok, thanks. I understand. If i want a big different I have to save up for an other engine. I think ebay is the only way.

But.. If i want, where can i get a Pre-serpentine type 4.2 crank? I have seen at rimmerbros, realsteel etc, and they don't have it.

Tamas

Tamas,

Turner Engineering had some I think for £190.00 but you will need at least custom pistons although again I have heard of machined low comp 3.9 pistons being used but not for high performance use really, 4.2 pistons are hard to find same bore as 3.9 but different compression height which is distance from centre of gudgeon pin to top of piston.

Kevin.

OK, I'm thinking on it.

Thanks for all!

Tamas
From Hungary

Tamas, I started working up some combos for the 3.5" bore with a longer stroke crank, maybe a 4.6 crank turned to fit the early block. If machine work is much less expensive there it may be worth considering.

How hard is it to get USA engine parts there? Is it possible to get the newer Ford 4.6 pistons there? Actually what engine parts are common? Maybe we could create a combo using pistons from a common engine there. Germany isn't far away are their car parts expensive for you guys?

I guess I'm asking what are the most common engines driving around Hungary? I would assume German cars. Is that correct?

If that is correct then you could potentially get some BMW M10 2.0L flattop pistons (link to FAQ below) combined with the stock 5.66" rods from the Rover 3.5L. Then get a Rover 4.6 crank and offset grind the rod journals to a total stroke of 3.28". The parts you'd need to find would be the M10 pistons and the 4.6 crank. Final displacement: 252ci. (4135cc)

Here's a link to the FAQ with piston info on it:

[www.bmw2002faq.com]

The necessary mods to the M10 piston would be enlarge the wrist pin hole in the piston for the slightly larger Rover 3.5L wrist pin. From 22mm to 22.225mm (.875"). It looks like you can order M10 pistons that are 90mm. Maybe they come bigger too.

Just tossing out a quick idea to look around at what's there. Maybe a combo of different makes would be a less expensive way of increasing displacement. I'll see if I can find another option.