Attn 2TG Guru's info on 88262 head wanted. *now with pics*

[Turdinator]

I have only recently become aware that my 3/2tg hybrid is unusual in that it uses a 13T block and a 11111-88262 2TG head. After doing some research it would appear the 88262 head is not the traditional hemi design. But a offset/oval/kidney shaped design depending on who's info you wish to believe. Most people recommend not using this head. I have been unable to find any pics of the combustion chamber so far. I intend to remove my head in the next month and will definitely post some pics when i do but any info i can get now would be greatly appreciated.

Does anyone have any concrete info regarding this head for performance use? Other than not being able to use the standard 3T pistons is there any other drawbacks? People have speculated that they are harder to get high compression from. Yet my PSI per cylinder is still as high if not higher than shelldrakes and we believe i have more aggressive cams.

TheToyman75 hopefully you find this thread. After trawling the old forum i see that you were trying to get hold of a 88262 to play with. Did this ever happen? What were the results?

Thanx
Marcus

[cooter]

hey im flying to perth tonight where ive got a semi disassembled 88262 head. still has cams. if u want i can get some photos over the weekend of whatever is needed.
cheers
craig

[styler]

my old hybrid motor used to run forged 89mm flat top pistons and this may be the case with yours, it had a 222 head that had been welded up to reduce the chamber size increasing compression to what was needed (actually looks similar to 262 head) its a lot of work though! or it is possible your motor has had the chamber ground out to suit 3t pistons which is also loads of work and not really practicle.

my guess is that its not a hybrid, its just using a replacement 3t block. so a 2tg crank and 262 pistons are in there, we'll see once the heads off.

as far as i remember...

the hybrid uses any 2tg head, just not the 262 because the 262 needs the pistons to match, the only pistons to use with the 262 head are only the pistons from the 262 2tg, no other 2tg or 3t piston has a suitable design for the 262 head.

so you have to use 262 pistons with a 262 head, and you cant use any 2tg pistons with a
3t crank for a hybrid motor as they are the wrong height. so its the 262 head and matching 262 pistons and 2tg crank or nothing.

for a hybrid you can use the 220, 222, 260 or 261 head for the hybrid with 3t crank AND 3t pistons. these are all standard style hemi heads.

out of these heads there are also some differences:

220 - smaller valve, 248 cams, 9.8 or 9.2 compression, single springs
222 - big valve, 256 cams, 8.8 compression, single springs
260 - big valve, cams ??, 9.8 or 8.4 or 8.7 compression, double springs
261 - big valve, cams ??, 8.3 or 8.4 compression, double springs
262 - big valve, reinforced, 256 or 244 or 240 cams, double springs

^ these head specs can be found on 2tg spotters guide.

[TheToyman75]

Turdinator,

The 262 head DOES HAVE offset combustion chambers. It means hi compression dome top pistons may need the dome to be machined to suit the chamber size. It just depends how proud the dome sits.

For ease of assembly and headache prevention I suggest using a 260 or 261 head for a high comp N/A engine.

[Turdinator]

hey im flying to perth tonight where ive got a semi disassembled 88262 head. still has cams. if u want i can get some photos over the weekend of whatever is needed.
cheers
craig

If its not too late craig this would be great!

my old hybrid motor used to run forged 89mm flat top pistons and this may be the case with yours, it had a 222 head that had been welded up to reduce the chamber size increasing compression to what was needed (actually looks similar to 262 head) its a lot of work though! or it is possible your motor has had the chamber ground out to suit 3t pistons which is also loads of work and not really practicle.

Interesting. Are the combustion chambers on the 262 the same volume as the other 2TG heads?

my guess is that its not a hybrid, its just using a replacement 3t block. so a 2tg crank and 262 pistons are in there, we'll see once the heads off.

I think this is very unlikely. Too much power through the rev range. At the last vic dyno day i ran mine after a stock 2TG with dellorto carbs and a worked 3/2TG (shelldrakes) and my power line was higher right through the rev range than either. If its a 1600 i'll be very impressed with whoever built it.

[cooter]

hey mate yeah i can get pikkies of whatever ya need. ive got a full dissasembled 88262 so just let me know what parts u wanna see. and about the combustion chamber volume i know an efi 88261 head is 62cc. ill get some perspex n suringe tomoz an measure the 88262 head
cheers
craig

[Turdinator]

hey mate yeah i can get pikkies of whatever ya need. ive got a full dissasembled 88262 so just let me know what parts u wanna see. and about the combustion chamber volume i know an efi 88261 head is 62cc. ill get some perspex n suringe tomoz an measure the 88262 head
cheers
craig

The ccs would be great. Its pics of combustion chamber i'm most interested in. But if you have the matching 2TG pistons i wouldn't mind a pic of them to.

[cooter]

yep no worries will do that tomoz. and yeah got pistons so ill get some photois of those too
cheers
craig

[cooter]

ok after pulling out the 262 head and the pistons that i know came out of it im a bit surprised.

the cams that are in it are marked 88262 but the 2 is stamped out and a 1 stamped next to it. strange

the hybrid uses any 2tg head, just not the 262 because the 262 needs the pistons to match, the only pistons to use with the 262 head are only the pistons from the 262 2tg, no other 2tg or 3t piston has a suitable design for the 262 head.

so you have to use 262 pistons with a 262 head, and you cant use any 2tg pistons with a
3t crank for a hybrid motor as they are the wrong height. so its the 262 head and matching 262 pistons and 2tg crank or nothing.

i dont think this is entirely true.

the pistons that came out of my 262 had 261 stamped on the skirts. and dont have that funny offset combustion chamber.



and



3t-c on right 261 on left

heres the photo of the 262 combustion chamber too




and i dont have acces to a decent sized suringe atm but the ma is going to pik one up from work tonight so ill be able to get that combustion chamber capacity tomoz
cheers
craig

[TheToyman75]

A 262 headed 2TG will have 262 cast into the pistons and has offset combustion chambers.

What made you think yours was a 262 ???? Curious ?

[cooter]

because it had a gex2 timing inspection plate and no head number cast into the front of the headf. just has yamaha and that old skool toyota symbol. im pretty sure u confirmed it as an 88262 ages ago for me rod
craig

[TheToyman75]

mmm Thats odd man. I though you said yours had no casting numbers on it a while ago.

Its trhe only one I have ever seen without the offset chambers and pistons. The 261 pistons deffinatly put them as 261 items and the restamped 262 cams p[oint towards it maybe being a crossover period engine. IE, new casting blank (No numbers) but all 261 internals ? Either way it makes for a great head to have.

Maybe not all heads with no casting numbers have the 262 pistons and chambers ?

I can't wait to see whats in Turdinators now.

[cooter]

haha yeah interesting. its also to note that it came from an 81 te71. i think thery changed the motor in the middle of 80/81 so maybe my car is a very early 81 model.
79/80 probs have 88261 and 81/82 have 88262. when u said it was an 88261 that made me wonder a bit cause i also have another 88261 which actually has it stamped on the head. the rocker cover on my 262 is also the last style with the plastic oil cap at the back on the left and the large bold toyota dohc with no raised edges on the right.

so do u think its worth doing anything to my 262 head?? cause im needing another head to rebuild and was gonna just ditch the 262 head cause of no hybrid poss. but if i can with this one and ur saying its a good head it may be worth using
dunoo
craig

[TheToyman75]

Craig,

From what I can see in the photo's I'd be using that "262" head. The combustion chambers look to be the "normal" hemisperical design so there is no reason not to.

[cooter]

great cheers rod
craig