spinningfish Posted April 7, 2015 Report Share Posted April 7, 2015 Hello there! I was wondering whether anyone can help... I'm about to pop my 4.6 RV8 lump into my FHC TR7 and sourced an SD1 sump for the motor. I've been told that the counter-balance weights on a 4.6 will make contact with an SD1 3.5 and the only option is to hammer it to allow it to clear. Whilst I'm not adverse to a bit of tin bashing, I was wondering whether anyone sold a custom spacer setup to allow the clearance? Can't find anything on the internet, but would much prefer something neater if possible. Many thanks in advance Quote Link to post Share on other sites
Christopher Kenneth SMITH Posted April 7, 2015 Report Share Posted April 7, 2015 Probably the man to ask would be Steve at S + S Preparations - they sort most of my 7s and 8s - 01706 874874 ... i have no financial interest in the company although my bank manager may disagre! Quote Link to post Share on other sites
TriumphV8 Posted April 7, 2015 Report Share Posted April 7, 2015 I have a crank with 98mm stroke in use, the most that is possible. It was formerly an externally balanced crank because they did not manage to bring all the counterweight into the engine and there is also a little bit of trouble with the rods hitting the pan if I remember correctly, but no big deal. I warmed the areas and took a small hammer not to bend the gasket area. With lots of small hits the material was stretched..... All was done within half an hour.... Quote Link to post Share on other sites
Motorsport Mickey Posted April 7, 2015 Report Share Posted April 7, 2015 I've done it the other way on a 3.9 litre ! Had an off at Silverstone which included some grass tracking and developed an engine knock which when inspecting it after the race found clumps off earth and grass wedged between the sump and subframe. The off had pushed the sump in (only a couple of mm) but enough for the conrods to touch the sump. Cured it by welding a 12mm nut onto the depressions on the sump and screwing a threaded rod upwards into it through a hole drilled through the subframe, then pulled the sump back out by tightening nuts the other side of the subframe. Based upon that and the knowledge of how close the conrods pass even on a smaller 3.9 litre I'd think you have a decent chance of adjusting the contour of the sump quite easily with a little heat and a smallish ball pein hammer. Turn the engine over first to find some witness marks on the inside of the sump for the areas to relieve. Mick Richards Quote Link to post Share on other sites
spinningfish Posted April 15, 2015 Author Report Share Posted April 15, 2015 Sorry for the slow reply! Many thanks for the info. Hammer time! Minus low crotched trousers... Quote Link to post Share on other sites
Wilfried Posted May 15, 2015 Report Share Posted May 15, 2015 I am a bit puzzled reading this discussion: I had learned that the cranks must never plunge into the oil bath in the sump. If the (longer) cranks of a modified engine can nearly touch the bottom of the sump, they will certainly splash the oil all over the inner of the engine.....Is there something that I have missed? Wilfried Quote Link to post Share on other sites
Motorsport Mickey Posted May 15, 2015 Report Share Posted May 15, 2015 (edited) Profiled sump. The front of the engine overhangs the steering rack and there is only a couple of inches between the top of the steering rack and the bottom of the block. So the main reservoir of the sump is at the back (about 6" deep)which then sweeps up leaving the front half of the sump only about 2" deep which passes over the top of the steering rack. That's why when I had my "off" at Silverstone the earth scooped up by the front of the subframe wedged into the space between the steering rack and the sump and pushed the sump upwards 3 or 4 mm. Mick Richards Edited May 15, 2015 by Motorsport Mickey Quote Link to post Share on other sites
TriumphV8 Posted May 16, 2015 Report Share Posted May 16, 2015 Is there something that I have missed? As Mickey said, only the 4 rear cylinders have oil below them. There starts another problem with long stroke crank: The Americans knew how to draw a good V8. What we did is building some more stories on a normal house hoping that it will work and if not cure the problems. One really problem left are cylinders 6 & 8 with long stroke cranks. The rods and counterweight do not drop into the oil but they are too close leading to oil splash up to the cylinder bores. The oil rings can not handle that and excessive oil deposits can be found in the chambers and at the spark plugs. It is a good idea to take some remedy to avoid that splash! Quote Link to post Share on other sites
Odd Posted May 16, 2015 Report Share Posted May 16, 2015 6 and 8? Not 7, or 5 for that matter, ? Quote Link to post Share on other sites
Motorsport Mickey Posted May 16, 2015 Report Share Posted May 16, 2015 Any of the rods that are immediately over the reservoir at the rear of the engine. If you alter the sump into a Group A copy with a small internal square baffle in the bottom (about 3" square) that the pick stands in and engineer a "swinging" door system for oil in and oil out of the baffle, it restricts the amount of surge and I never suffered from oil splash up because the inertia of the oil is greatly reduced. The Group A sumps also have "wings" about 5" square on either side of the sump reservoir to increase the amount of oil held, again with baffles to allow oil to flow from them into the 3" square baffle under hard cornering. As the oil is forced across the sump the swinging door on the positive side shuts trapping the oil around the oil pick up, and the swinging door on the negative side is allowed to be opened by the oil movement and fed with the extra oil from the "wing" on that negative side. If I can find a photo of mine after I finished making it I'll post it. Mick Richards Quote Link to post Share on other sites
TriumphV8 Posted May 16, 2015 Report Share Posted May 16, 2015 (edited) Hi Mick, would like to see photos or drawings from the sump! 6 & 8 shuffle the oil upwards and from that they both suffer more from the oil as 5 & 7 chambers and plugs look more than the others. As my TR6 is for street use I did not have the problems with picking up air and only had to prevent the oil from the crank. I extended oil pan forward close to the TR6 cross tube and lowered oil level keeping the total amount of oil in. A baffle plate like a going round ring prevents oil from splashing upwards. It is welded to the oil pan, similar to my TR6: Edited May 16, 2015 by TriumphV8 Quote Link to post Share on other sites
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