MGB & GT Forum

Pondering whether to go the above way but looking at the project for a RHD car fitted with inverted oil filter, would there be sufficient clearance to mount the twin SUs’ ? Second question, am I right in thinking I cannot fit non-inverted oil filter type due to position of steering shaft ? This is where my idle thoughts can lead me into trouble. Seeking advice from the more learned, thanks Kevin

"am I right in thinking I cannot fit non-inverted oil filter type due to position of steering shaft"

No (but we don't know anything about how your car was converted).

Hanging oil filters EG Tecalamit/Purolator were common - I still run my Tecalamit

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Mk1: CKD 11/66 first registered 8/5/67; owned since 3/77. 18GB +40 balanced. Peter Burgess BVFR head. Piper 285. 123. FidanzaFW. 4synch c/r box. Superpro. Nut and bolt rebuild 2010 - 2015. Tartan Red.

GT: 12/78. VW Golf guards, flush fit front and rear valances, frenched indicators, Mk1 rear lights - LED lights. 'Worked' Rover V8, Monsoon ECU for EFI. Commodore VSV8 GM4L60E, Lokar tiptronic shifter & Quick4 controller. Vintage Air A/C. FC IFS. CCE 4 link rear. Salisbury with Quaife. Jaguar Storm.

I thought I'd share as I've only just read the chapter and it put me off the idea of a crossflow head (not because I have any wisdom of my own).

In "How to Power Tune MGB 4-Cylinder Engines", Pete Burgess states that in unmodified form the total horsepower achievable with the HRG Derringer crossflow head is lower than a stock head, and in modified form the total power from both heads is matched, although in both cases the crossflow head has more mid-range torque if the compression ratio is raised to 10.5:1.

You may already know this but thought I'd let you know!.

Following on from Dylan's post if you are wanting to achieve more power whilst retaining the 1800 then do yourself a favour and buy Peter's excellent book on how to power tune the MGB. He says it's updated and available.

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Mk1: CKD 11/66 first registered 8/5/67; owned since 3/77. 18GB +40 balanced. Peter Burgess BVFR head. Piper 285. 123. FidanzaFW. 4synch c/r box. Superpro. Nut and bolt rebuild 2010 - 2015. Tartan Red.

GT: 12/78. VW Golf guards, flush fit front and rear valances, frenched indicators, Mk1 rear lights - LED lights. 'Worked' Rover V8, Monsoon ECU for EFI. Commodore VSV8 GM4L60E, Lokar tiptronic shifter & Quick4 controller. Vintage Air A/C. FC IFS. CCE 4 link rear. Salisbury with Quaife. Jaguar Storm.

Have you already bought the cross flow head, is it already with you so you are looking to fit it or is this just something you are considering buying ?

Remote oil filter is a nice touch on a car with cross flow we do the same thing on race, and most of use put the along right side fender rail. One thing it allows you to do is use oil oli filter housing that allows you to use a better filter, most folks go the ford route, and I use a high end Wix racing oil filters. There's a lot more going here than just a remote oil filter, but you can see how I mounted mine. Another option would be to get one of the aftermarket hanging oil filter housing made for the earlier MGBs to replace the cartridge housing with, but the remote housing is a lot easier to deal with.

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Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com

I don't think that the statement that you would get less power with the crossflow head is true. The modern aftermarket crossflow, maybe, but the original HRG gave much better results than any stock head.

See https://www.rhodoworld.com/f/HRG_Information.pdf

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Bill Spohn www.rhodo.citymax.com/carstuff.html
Current: 1958 MGA Twincam (race car (170 bhp)),1962 MGA Deluxe Coupe (98 bhp)
1957 Jamaican MGA (200 bhp)1965 1971 Jensen Interceptor (350 bhp)
2009 Pontiac Solstice GXP Coupe (375 bhp)
2007 BMW Z4M coupe (340 bhp)
Recent: 1969 MGC roadster (175 bhp),Jensen CV8 (375 bhp),
1969 Lamborghini Islero S (350 bhp), 1988 Fiero GT turbo (300 bhp)
North Vancouver BC

Reply to Chris…. No have not bought cf head yet still sorting through the side issues with advice being sought from the learned on here. Currently investigating whether y RHD conversion ie. steering shaft+ inverted oil filter will not pose clearance issues. One of the other guys on here has suggested a particular book which is recommended reading before going down this rabbit hole….. Kevin

I think the first question is, what are you hoping to achieve with a crossflow head? In theory they should perform better than the stock head - but I don't think they perform *much* better (at least not on a street setup). I've also heard (but have no first hand experience) that at least some of the crossflow heads have smaller passages than stock. I suspect you may get a modest boost in performance, but if it had the potential to transform the engine then everyone (including the factory) would have done it. They are pricey.

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Terry Ingoldsby
terry.ingoldsby@DCExperts.com

BMC had no interest in making new heads work - they just slowly tried to keep the existing heads working and any changes were forced on them (e.g. hardened seats etc.)

The HRG head gave around 10 bhp on an MGA using stock carbs - that is a 12% bump.

The more recent alloy crossflow heads made by others were more restrictive and needed much work before they would give that sort of bump - search for Sean's comments on the flow of unmodified MSX modern heads.

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Bill Spohn www.rhodo.citymax.com/carstuff.html
Current: 1958 MGA Twincam (race car (170 bhp)),1962 MGA Deluxe Coupe (98 bhp)
1957 Jamaican MGA (200 bhp)1965 1971 Jensen Interceptor (350 bhp)
2009 Pontiac Solstice GXP Coupe (375 bhp)
2007 BMW Z4M coupe (340 bhp)
Recent: 1969 MGC roadster (175 bhp),Jensen CV8 (375 bhp),
1969 Lamborghini Islero S (350 bhp), 1988 Fiero GT turbo (300 bhp)
North Vancouver BC

The comments above from Bill, Terry and Hap are very relevant. The current aluminum crossflow heads available today flow less than the old 1326, and must be seriously modified to even equal the stock head's flow (flow = HP). So, you start with the over $1000 cost of the blank head, then spend X - $$$ to get a competent port job, then you have something. But then, you need to build a bottom end with quality connecting rods and pistons, balance the entire rotating mass, and use at least a lightened flywheel if not aluminum. Oh yeah, don't forget a quality hand built manifold and some either trick HS4's or HS6's (this is where the HS6 is a good choice for an MGB). If I'm not mistaken, you just spent in the neighborhood of $8 - 10 K. Like Terry said, what are you trying to achieve?
My friend Jimmy had that engine built. If I'm not mistaken, the cylinder head Sean sent is the prototype for his MSX product, and Hap built the bottom end. I built the rest of the car, and the remote oil filter that Hap mentioned is absolutely necessary. It gets real busy on the passenger side (NA spec) of the engine compartment with the carbs and intake covering up the distributor, which means that if you have "man hands" setting the points requires removing the carb set.
On the other hand, if you simply like the look of the crossflow, you should get one and, with the exception of the oil filter, make the engine compartment look really good.

Have fun

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If ignorance is bliss, I must be the happiest man alive!
Signed

RUFUS
67 Roadster

It seems like this would be a very good application for distributorless ignition. Port FI while you're at it. I believe individual intake ports would make port FI a possibility.

Bob makes a good point.

Have fun

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If ignorance is bliss, I must be the happiest man alive!
Signed

RUFUS
67 Roadster

Obtaining a cross flow head and having it modified to provide any noticeable performance improvement over the standard MGB head will be expensive. With respect Im not clear on why you have been led to regard this as a cost effective route to a performance upgrade. There's nothing wrong with someone striking out on their own in a different direction to make a new discovery, its creditable stuff indeed but bear in mind these cars have been around for several decades now with millions of owners and there is a reason that those seeking performance uplifts tend to stick to the tried and tested performance upgrades after asking around. E.g port & polish, bigger valves, camshaft upgrade etc or take the path to a Rover V8 or swap to one of several modern engines. The crossflow heads were hailed as a good idea on the MGA but then so was that car's ill fated twin cam head for a short while....

To quote from page 28 of Roger Parker's excellent book, Everyday Modifications For Your MGB ,where he mentions the crossflow head

"While these heads offered impressive performance increases in their day, developments with standard MGB heads made the seven port crossflow head's overall performance initially slightly disappointing but this can be improved"

He explains it can provider wider opportunities for carburetion such as twin side draught Webers etc which can be an attraction but then goes on to say " Well modified original 5 port heads can achieve greater peak power"

There was a time in the UK back in the 70's where people used to go on about wanting a crossflow head on a B and on other cars of the era without ever knowing anyone who had got one, just urban myth. This was nothing to do with any proper factual information on the B but all to do with the public perception at the time that the Ford Kent engine, which was well known and everywhere at the time, had been significantly improved by the advent of a crossflow head. The public started to think of crossflow as good and of non crossflow engines as gutless and old hat, which was nonsense. Other urban myths at the time were that certain cars were designed to handle better with weights in the boot and that one manufacturer had recommended carrying a sack of cement to improve rear end handling - they never did.



Edited 1 time(s). Last edit at 2024-04-11 08:16 AM by Not-Anumber.

Peter Burgess HRG Derrington article, "Precious Metal" from "Enjoying MG" magazine below. If anyone wants a copy just let me know.

0 to 60 in 7 seconds vs. 14. (website listed below states 12.9 for a 1965 MGB)

And that is with no work done to improve the original HRG head. I ran the exact engine set up shown in his article; HRG head with BMC 714 camshaft, twin DCOEs and LCB exhaust for over 15 years so I know it well. Performance is now even better with all the modern upgrades and head work performed on the engine. I have not measured anything yet but am hoping to 0-60 time is now down to around 5 seconds... Not bad for a 1972 MGB/GT when you consider that a 1982 Ferrari 308GTSi was 7.6 seconds!!!!

https://www.zeroto60times.com/vehicle-make/ferrari-0-60-mph-times/

I'm pretty sure the stock HRG outperforms a stock head.

Just sayin'

P.S. On the flip side, I wouldn't waste my money on the aftermarket head. It is not up to par with the HRG.

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Those who confuse Burro and Burrow don't know their @ss from a hole in the ground...