Anybody out there in Diesel Land tried an Irvine 61 conversion - and if you did, what did you think of it? Would also welcome general opinions as to whether it's strong enough for dieselizing.

John,


It should be strong enough to last as a Diesel.

Try writing to AJC, to see what he can offer you. It should be more attractively priced than other available conversion kits.

John, do you already have the Irvine .61? Thanks

Hello again. No, not yet. I really have my sights set on an MVVS 61 after favourable replies to my enquiries on this forum, but I'm having a problem getting hold of one - the UK supplier doesn't have stock, and I think my e-mails to Pe Reivers are going astray. So I thought the Irvine 61 - which I can easily get and know to be top class - might be a viable alternative. As far as the conversion head is concerned, I've had one of AJC's heads before (for TT Pro 46) and I was very pleased with the quality, service and price. I still hanker after the MVVS though, so will wait a while to see if the supply situation improves.

John,


There are other MVVS dealers out there, who can supply this engine.
...But you apparently don't want to receive E-mails, or PMs from members of this forum.

Thanks for reply. Only recently got involved with PCs (after resisting for years), and my children tell me it's best to be cautious about giving out e-mail addresses. And I don't know what a PM is - Personal Message?
In any case, supply problem now in hand - Pe R has been in touch.

Bear in mind that when Irvine went about producing their 40 diesel they started with converting a 40. they ended up with a smaller carb, a heavier crank, a longer stroke, a narrower bore, revised porting, and, of course, a new head. Otherwise the conversion was a doddle.

i have an old hp 61 gold cup I wish to convert (I am dyning to because it is a beast) to see what it dose what do you think ?

Piece of cake then!!

as far as i know irvine 40 d and q40 are identical exept for the head, mufler and smaller carb without pressure feed(an old myth that diesels should work this way)

L, its not a myth, every Diesel conversion I run has a smaller than stock carb except my Irvine .53 and my two LA conversions. No other carb will fit the Irvine .53 and the LAs already have a smaller carb than their Schnurle ported cousins.

The Q40 is a conversion of the 40D. I'm not absolutely sure if the crank was changed to give a bigger passage, but certainly the head, muffler and carb were changed.

Just checked the parts list - the Q40 has a different crank.

No muffler pressure is used on the diesel, as with a small bore carb it doesn't need it, and also to prevent the ingress of water vapour into the fuel.

The the Q 40 and 40D both have the .46 crankshaft in them.

I like Hobbsy have the Q40 and Irvine 40 Diesels, Indeed they both use the 46 crank. Which was produced first?? But everthing swaps
out. My Q40s became instant diesels using the stock irvine 40 head and the Davis head. There are quite a few posts on this if you guys
look back on this site, Both Hobbsy and I show the props, rpms, etc obtained martin

[quote]ORIGINAL: dieseldan

I like Hobbsy have the Q40 and Irvine 40 Diesels, Indeed they both use the 46 crank. Which was produced first?? But everthing swaps
out. My Q40s became instant diesels using the stock irvine 40 head and the Davis head. There are quite a few posts on this if you guys
look back on this site, Both Hobbsy and I show the props, rpms
I also have the regular irvine 40 and 36 which AJ made heads for since not comerically available the 36 is quite close in preformance
to the 40. Remember these are the engines that preceded the MARK lll maroon series with these engines no longer in production
the OS LA 40 series with Davis heads are an excellant replacement without a lot of $$ martin

The 40D crank is part #is S-46-2175H
The Q40 crank is part #is S-46-2175

All three cranks are the same save for one difference, the older silver series .46 cranks have a stud in the crank shaft to bolt the prop on, the Diesel and the Q40 have threads cut on the crankshaft. I suspect that the new red .46 cranks are identical to the Diesel and Q 40.

manufecturers like changeing part number for nothing just to make the spares cataloge more interesting

Just picked up a few spares, head and con rod for the 40D. The orginal irvine package for the rod reads Q40/40D martin

The 40D was produced first. The Q40 is a development of the 40D.

I still have spares for many of the Irvine engines, including the 40D. Also have a few new engines left in stock, mostly the Mk IIIs. I have one reconditioned 40D - I'm not parting with my own 40D!

DSLarkin I intend to keep these around for a long time I think 6 plus parts would like to pick up a "junker" just for a crankcase casting
and engine front have everything else martin